Here is an aggregation of all the news and late-breaking studies presented at the 2018 Heart Rhythm Society (HRS) Scientific Sessions in May. 

Late-breaking Studies:

• Catheter Ablation vs. Antiarrhythmic Drug Therapy for Atrial Fibrillation: Results of the CABANA Multicenter International Randomized Clinical Trial

• Prevention of Arrhythmia Device Infection Trial (PADIT) — Novel Antibiotics Can Help Lower EP Device Infection Rates

• A Prospective, Blinded Evaluation of a Novel Filter Designed to Reduce Inappropriate Shocks by the Subcutaneous Implantable Defibrillator

• Three-year Outcomes After Botulinum Toxin Injections into Epicardial Fat Pads for Atrial Fibrillation Prevention in Patients Undergoing Coronary Artery Bypass Grafting

• Myocarditis Is an Underrecognized Etiology of Symptomatic Premature Ventricular Contractions - Insights from The Myocarditis and Ventricular Arrhythmia (MAVERIC) Registry

• Lower Adherence Direct Oral Anticoagulants Use Is Associated with Increased Risk of Thromboembolic Events Than Warfarin - Understanding the Real-world Performance of Systemic Anticoagulation in Atrial Fibrillation

• Atrial Fibrillation Burden and Impact on Mortality and Hospitalization — The CASTLE-AF Trial

• Device-related Thrombus After Left Atrial Appendage Closure with Watchman: Incidence, Predictors and Outcomes

• Randomized Controlled Trial of Cardiac Contractility Modulation in Heart Failure: The FIX-HF-5C Study

• Targeted Left Ventricular Lead Implantation in Non-Left Bundle Branch Block Patients: Primary Results of The Enhance CRT Pilot Study

• A Randomized Pragmatic Trial of Strategies of Permanent Pacemaker Versus Implantable Cardiac Monitor in Older Patients with Syncope and Bifascicular Block

• Intramural Needle Ablation for Refractory Ventricular Arrhythmias: Safety and Outcomes

• First In-human Data on Multi-Electrode Contact Mapping Plus Ablation for Treatment of Atrial Fibrillation

• Feasibility of Extravascular Pacing, Sensing and Defibrillation from a Novel Substernal lead: The Acute Extravascular Defibrillation, Pacing and Electrogram (ASD2) Study

• AV Synchronous Pacing with a Ventricular Leadless Pacemaker: Primary Results from the Marvel Study

• First Clinical Report of Atrial Fibrillation Ablation with Pulsed Electric Fields: An Ultra-Rapid, Tissue-Selective Modality for Cardiac Ablation

Other Key Heart Rhythm 2018 Study Presentations: 

Heart Rhythm Society Recommends How to Prepare for Cybersecurity Threats to Cardiac Implantable Devices

Link Found Between Post-Traumatic Stress, Increased Risk of AFib

Marijuana Use Does Not Increase Risk of Arrhythmias, Might Reduce AFib Risk

Exposure to Air Pollution on Cold Days Can Trigger Sudden Cardiac Death in Women

Consumer Smart Watches Accurately Measure Paroxysmal Supraventricular Tachycardia

View photos from HRS 2018

Follow other HRS news

Link to the Heart Rhythm Society 2017 Late-Breaking Electrophysiology Trials
 

 
#HRS2018, #HRS18

May 24, 2018 - Medtronic plc announced results from a research study demonstrating the feasibility of a novel approach to delivering pacing and defibrillation therapy in which a lead is placed under the sternum (breastbone), outside of the heart and veins. Data from the Acute Extravascular Defibrillation, Pacing and Electrogram (ASD2) study were presented during a late-breaking session at Heart Rhythm 2018, the Heart Rhythm Society's 39th Annual Scientific Sessions, May 9-12 in Boston.

The results of the international ASD2 feasibility study, an important step in the Medtronic extravascular implantable cardioverter defibrillator (EV ICD) clinical development program, confirmed that an investigational extravascular ICD lead can sense, pace and defibrillate the heart. This offers a potential future alternative to traditional transvenous ICD systems.

"Clinicians are highly interested in the potential for an extravascular ICD solution to provide both pacing and lifesaving defibrillation therapy without leads placed inside the heart or vasculature," said Lucas V.A. Boersma, M.D., Ph.D., cardiologist at St. Antonius Hospital, Department of Cardiology, Nieuwegein, the Netherlands and professor of cardiology, Academic Medical Center (AMC), University of Amsterdam, the Netherlands. "The ASD2 study offers very encouraging clinical insights, which bring us closer to implanting the first chronic investigational system in ambulatory patients."

The Medtronic EV-ICD System, which currently is in development and not available for use or sale, is a new approach to implantable defibrillation therapy that may offer the benefits of current transvenous defibrillators. In addition, the system may address current limitations of subcutaneous implantable defibrillators, including their inability to provide painless bradycardia pacing or antitachycardia pacing (ATP), and their larger size.

In ASD2, 79 patients who were already scheduled for elective cardiac surgery or a subcutaneous or transvenous ICD implant had an investigational EV-ICD lead inserted temporarily under the sternum and evaluated in conjunction with either a defibrillation patch or a defibrillator emulator. The ICD lead was designed to sense activity in the ventricles (lower chambers of the heart), provide pacing to the ventricles, and deliver a 30-joule defibrillation shock after ventricular fibrillation (VF) was induced.

Ventricular pacing was successful in 97 percent of patients, and shocks successfully terminated 83 percent of episodes, consistent with prior clinical studies of existing ICDs.1

Seven adverse events were reported in six of the 79 studied patients. As with any feasibility research evaluating a new procedure, the investigational procedure and lead implantation tools were refined during the study, with further technique training and education provided to all investigators in an effort to reduce the adverse event rate in future patients.

For more information: www.medtronic.com

Read more about HRS 2018 late-breaking clinical trials

July 2, 2018 — University of Washington (UW) Medicine cardiologists have developed a tool to predict which heart failure patients stand to gain most, and least, from an implanted defibrillator.

About 30 years ago, doctors started putting implantable cardioverter defibrillators (ICDs) in patients who had survived a sudden cardiac arrest. These palm-size devices, wired to the heart, could stave off another such event by recognizing a dangerous rhythm and providing a lifesaving shock, returning the organ to normalcy.

In subsequent years, cardiologists developed a rationale to place ICDs in people who had not sustained a cardiac arrest but who had a diagnosis of chronic heart failure and other risk signs.

But as the population of implant recipients grew, cardiologists learned that many devices were giving shocks when no peril was evident. Many inappropriate jolts landed patients back in the hospital – and each needless shock stoked fears of another. What’s more, studies began to show that two-thirds of ICDs, mostly in older people, never gave even one shock; those patients died of unrelated causes, challenging the thinking behind their implants.

“This is the main reason that ICD placements have diminished in recent years. Doctors want to avoid these downsides, and they feel less able to predict who will benefit,” said Wayne Levy, a professor of medicine (cardiology) at the University of Washington School of Medicine. His research focuses on prognostic risk modeling in heart failure.

Levy and colleagues’ model will help doctors identify not just which patients merit consideration for an ICD, but which are likely to benefit most, and least, from the device. The model’s predictive value is demonstrated, Levy said, in a research paper published in the Journal of the American College of Cardiology-Clinical Electrophysiology.1

“We have validated the model with a gold-standard test: applying it to a previous trial in which patients were randomized to an ICD or no ICD – to see if the model would accurately predict, among those who got the device, who would benefit most. And the model worked very well,” he said.2

It is the very same Seattle Proportional Risk Model that Levy and colleagues published in 2015 to establish which heart failure patients were at greatest risk of sudden death.3 The only difference is presentation: Now the model is the brains to an online tool that any cardiologist can use, Levy said, to enter patient-specific data to discern the likelihood of an individual’s prospective ICD benefit.

The need for such a tool has existed for years but was heightened in February when the Centers for Medicare & Medicaid Services (CMS) announced it would cover future ICDs only if physicians could document a “shared decision-making” process had occurred with patient candidates.

That mandate, though, is inadequate because “the suggested model for that conversation simply identifies the benefits and harms associated with the device,” Levy said. “The illustration of benefit is based on the average patient; it likely doesn't represent the patient sitting in front of you who may be 15 years older with diabetes or lung disease or some other condition.”

As with CMS, hospitals are scrutinizing costs and patient satisfaction like never before. Levy thinks an easily accessible tool whose methodology has been validated gives cardiologists an evidence-based foundation for those conversations with patients.

“To be clear, the model isn’t making a recommendation about whether to place a defibrillator; what we’re doing is saying, if you put one in, this is the potential magnitude of benefit or non-benefit based on this tool. The physician and patient need to make their own conclusion whether to place an ICD,” he said.

For more information: www.electrophysiology.onlinejacc.org

References

1. Levy W.C., Hellkamp A.S., Mark D.B., et al. "Improving the Use of Primary Prevention Implantable Cardioverter-Defibrillators Therapy With Validated Patient-Centric Risk Estimates,"JACC: Clinical Electrophysiology, June 21, 2018. DOI: 10.1016/j.jacep.2018.04.015

2. Køber L., Thune J.T., Nielsen J.C., et al. "Defibrillator Implantation in Patients with Nonischemic Systolic Heart Failure," New England Journal of Medicine, Sept. 29, 2016. DOI: 10.1056/NEJMoa1608029

3. Shadman R., Poole J.E., Dardas T.F., et al. "A novel method to predict the proportional risk of sudden cardiac death in heart failure: Derivation of the Seattle Proportional Risk Model," Heart Rhythm, Oct. 2015. DOI: https://doi.org/10.1016/j.hrthm.2015.06.039

July 11, 2018 — Placement of implantable cardioverter defibrillators (ICDs) not meeting Centers for Medicare and Medicaid Services (CMS) National Coverage Determination criteria declined following the announcement of a U.S. Department of Justice (DOJ) investigation into potential overuse of such devices. This conclusion was drawn from a recent study of hospitals participating in the NCDR ICD Registry.

CMS created a National Coverage Determination for ICDs in 2005. The NCD incorporated the available clinical evidence and aligned payment practices for primary prevention ICDs in patients insured under Medicare.

The DOJ notified hospitals of an investigation into potential overuse of ICDs in 2010; the investigation was made public in January 2011. Upon the conclusion of the investigation in February 2016, the DOJ reached settlements with more than 500 hospitals for over $280 million total for Medicare claims not meeting the National Coverage Determination.

“When the National Coverage Determination was first announced, there were concerns about potential overuse of ICDs,” said Nihar Desai, M.D., MPH, lead author of the study and assistant professor of medicine at Yale School of Medicine. “Between 2007 and 2015, there were significant declines in the proportion of primary prevention ICDs placed for indications not meeting National Coverage Determination criteria at all hospitals with larger and more rapid declines after the announcement of the investigation at hospitals that reached settlements with the DOJ. There were similar declines observed among non-Medicare patients.”

Using NCDR ICD Registry data to determine if the DOJ investigation changed clinical practice, researchers analyzed 300,151 primary prevention ICDs in Medicare patients at 1,809 hospitals between January 2007 and December 2015. Of the 502 publicly named hospitals that reached a settlement with DOJ, 470 were matched to facilities in the ICD Registry. Two facilities were confirmed to have closed and 16 did not submit data or their data did not meet NCDR quality standards. Researchers also analyzed the data of non-Medicare patients to determine if the DOJ investigation impacted the overall patient population undergoing ICD implantation.

Patients receiving ICDs at both hospitals that did and did not settle with DOJ were on average 75.1 years old. Seventy-one-point-five percent were male, 41.8 percent had diabetes and 54.4 percent had suffered a heart attack. Hospitals that settled with the DOJ were larger, private facilities with higher case volumes and more likely to be located in the South and West regions of the United States.

The study used interrupted time series to investigate the changes in the proportion of ICDs not meeting the National Coverage Determination criteria at six-month intervals. Interrupted time series are used to estimate the associations with a policy intervention or other natural experiment when there are at least four data points both before and after the event. The model evaluated three time periods: pre-DOJ investigation (January 2007-December 2009); DOJ investigation announcement (January 2010-June 2011); and post-DOJ investigation announcement (July 2011-December 2015).

In the first half of 2007, 25.8 percent of ICDs at hospitals that settled and 22.8 percent of ICDs at hospitals that did not settle did not meet the National Coverage Determination. Over the full study period, there was a 16.1 percent decline in ICDs not meeting the National Determination Coverage criteria at hospitals that settled with the DOJ and a 12.1 percent decline in hospitals that had not.

The interrupted time series analysis found prior to the announcement of the DOJ investigation that the proportion of ICD placements not meeting the National Coverage Determination was relatively stable, and the rate of decline was modest and similar among all hospitals. During the DOJ investigation announcement, researchers found significant declines in the proportions of ICDs not meeting the National Coverage Determination at all hospitals. However, the rate was much larger and more rapid at hospitals that went on to reach settlements. At the end of the study, the amount of ICDs not meeting the National Coverage Determination criteria were similar in both groups.

Rates of ICD implants not meeting the National Coverage Determination criteria also fell among non-Medicare patients at both hospitals that did and did not settle with the DOJ.

Overall, there were declines in ICD implants not meeting the National Coverage Determination, but there was variation at the hospital-level. At top performing facilities, less than 3.8 percent of ICD implants did not meet the National Coverage Determination criteria while lower performing facilities had more than 14.3 percent of ICD implants not meeting the criteria.

“The hospital-level variation may reflect continued room for improvement but may also indicate a gap in the national coverage determination. As current guidelines state, care for a particular patient ultimately falls to the clinician and that patient and thus the guidelines may not fit all patients,” Desai said. “The DOJ did acknowledge there are valid clinical indications for placing an ICD outside the National Coverage Determination criteria. CMS updated the criteria in 2017 to include new clinical studies and updated guidelines.”

Study limitations include that all non-Medicare patients may not be included as hospitals are only required to submit data on Medicare patients—though 80 percent of participating hospitals report all ICD implantations, regardless of payer; there is no public list identifying all the hospitals investigated by the DOJ; and interrupted time series analysis attributes changes to a single factor. Lastly, researchers were unable to assess whether the DOJ investigations led to any barriers in the placement of clinically indicated ICDs.

The full study was published in the Journal of the American Medical Association.

For more information: www.jamanetworks.com/journals/jama

Reference

Desai N.R., Bourdillon P.M., Parzynski C.S., et al. "Association of the US Department of Justice Investigation of Implantable Cardioverter-Defibrillators and Devices Not Meeting the Medicare National Coverage Determination, 2007-2015," Journal of the American Medical Association, July 3, 2018. doi:10.1001/jama.2018.8151

August 9, 2018 — Medtronic plc announced the start of a pilot study of its investigational Extravascular Implantable Cardioverter Defibrillator (EV ICD) system, with the first patient implant performed at Christchurch Hospital in New Zealand. The implant represents the first intended long-term patient use of the device, which is similar in size to transvenous ICDs.

“The Medtronic EV ICD system has the potential to deliver the benefits of traditional ICDs while eliminating the risks that can occur when leads are implanted inside the veins and heart,” said Ian Crozier, M.D., Department of Cardiology, Christchurch Hospital, Christchurch, New Zealand, and principal investigator (PI) in the Medtronic Extravascular ICD Pilot Study. “We are incredibly pleased to contribute to this important research that will serve as a key step in establishing the safety and efficacy of this new approach.”

The pilot study will assess the Medtronic EV ICD system in 20 patients at four sites:

• Christchurch Hospital (Crozier);
• Austin Health in Heidelberg, Australia (PI: David O’Donnell, M.D.);
• MonashHeart in Clayton, Australia (PI: Emily Kotschet, M.D.); and
• The Prince Charles Hospital in Brisbane, Australia (PI: Haris Haqqani, M.D.).

After implantation of the system, patients and their devices will be routinely checked to assess safety and device performance.

The Medtronic EV ICD system is intended to provide the benefits of traditional transvenous ICDs including lifesaving defibrillation therapy, antitachycardia pacing to painlessly terminate arrhythmias, as well as post-shock pacing to protect from sudden cardiac death; and bradycardia pacing to address abnormally slow heart rates. It also is the same size (33 cc) and shape, and is expected to have similar longevity as traditional ICDs, but without any leads (thin wires) in the veins or heart. The investigational EV ICD device is implanted in the left mid-axillary region below the left armpit, and the newly designed lead is placed under the sternum (breastbone). New procedure tools guide the delivery of the system.

Medtronic research teams developed the EV ICD System and have completed multiple early research and acute feasibility studies using the system components, including the ASD1 (Acute Sensing and Defibrillation), SPACE2 (Substernal Pacing Acute Clinical Evaluation) and ASD23 studies.

Read the related article Medtronic Study Confirms Feasibility of New Extravascular Approach to ICD Therapy

The EV ICD system is investigational and not approved for sale or distribution.

For more information: www.medtronic.com

References

1. Chan JYS, Lelakowski J, Murgatroyd FD et al. Novel Extravascular Defibrillation Configuration With a Coil in the Substernal Space: The ASD Clinical Study. J Am Coll Cardiol EP 2017;3:905-10.https://doi.org/10.1016/j.jacep.2016.12.026

2. Sholevar DP, Tung S, Kuriachan V, et al.  Feasibility of extravascular pacing with a novel substernal electrode configuration: The Substernal Pacing Acute Clinical Evaluation Study. Heart Rhythm. Published online 29Nov2017. DOI: http://dx.doi.org/10.1016/j.hrthm.2017.11.030

3. Boersma, LVA. Feasibility of Extravascular Pacing, Sensing And Defibrillation From A Novel Substernal lead: The Acute Extravascular Defibrillation, Pacing And Electrogram (ASD2) Study. Presented Heart Rhythm Society Scientific Sessions, May 11, 2018.

October 17, 2018 — The U.S. Food and Drug Administration (FDA) has reviewed information about potential cybersecurity vulnerabilities associated with the internet connection of Medtronic's cardiac implantable electrophysiology device (CIED) programmers. The FDA said it has confirmed that these vulnerabilities could allow an unauthorized user to change the programmer's functionality or the implanted EP device during the device implantation procedure or during follow-up visits.

The FDA reported Oct. 11 that Medtronic is issuing a software update to address a safety risk caused by cybersecurity vulnerabilities associated with the internet connection between the Carelink 2090 and Carelink Encore 29901 programmers used to download software from the Medtronic software distribution network (SDN) . This update is a voluntary recall correction by the manufacturer to address the safety risk caused by the cybersecurity vulnerability.

The cybersecurity vulnerability is associated with using an internet connection to update software between the CareLink and CareLink Encore programmers and the SDN. Software updates normally include new software for the programmer's functionality as well as updates to implanted device firmware. Although the programmer uses a virtual private network (VPN) to establish an internet connection with the Medtronic SDN, the FDA said the vulnerability identified with this connection is that the programmers do not verify that they are still connected to the VPN prior to downloading updates.

To address this cybersecurity vulnerability and improve patient safety, on Oct. 5, 2018, the FDA approved Medtronic's update to the Medtronic network that will intentionally block the currently existing programmer from accessing the Medtronic SDN.

As such, attempting to update the programmer through the internet by selecting the "Install from Medtronic" button on the programmer will result in error messages such as "Unable to connect to local network" or "Unable to connect to Medtronic." These errors are due to disabling the SDN and are not a result of a programmer or local information technology (IT) issue.

To date, there are no known reports of patient harm related to these cybersecurity vulnerabilities.

There are no updates to the CareLink 2090 or CareLink Encore 29901 programmers at this time. However, the FDA said Medtronic is working to create and implement additional security updates to further address these vulnerabilities.

Medtronic CareLink and CareLink Encore programmers are used during implantation and regular follow-up visits for CIEDs. These devices include include pacemakers to provide pacing for slow heart rhythms, implantable defibrillators to provide an electrical shock or pacing to stop dangerously fast heart rhythms, cardiac resynchronization devices to pace the heart to improve contraction to treat heart failure, and insertable cardiac monitors for long-term cardiac monitoring for irregular or abnormal heart rhythms.

Medtronic programmers allow physicians to obtain device performance data, check battery status, and adjust or reprogram device settings from a CIED. When necessary, the programmers are also used by Medtronic staff to update software in the implanted device. The programmer software can be downloaded and updated either through internet connection to the Medtronic SDN or by a Medtronic representative plugging a universal serial bus device (USB) into the programmer.

Read the completed FDA safety alert.

Recommendations for Healthcare Providers

The FDA said providers should continue to use the programmers for programming, testing and evaluation of CIED patients. Network connectivity is not required for normal CIED programming and similar operation. Other Medtronic-provided features that require network connections are not impacted by these vulnerabilities (e.g.,SessionSync). 

The FDA warned not to attempt to update the programmer through the SDN. If you select the "Install from Medtronic" button, it will not result in software installation, because access to the external SDN is no longer available. Future programmer software updates must be received directly from a Medtronic representative with a USB update.

The FDA recommends maintain control of programmers within the provider's facility at all times according to your hospital's IT policies, and to operate the programmers within well-managed IT networks. 

For recommended actions to better secure your computer network environment, refer to www.nist.gov/cyberframework or other applicable cybersecurity guidance.

Reprogramming or updating of CIEDs is not required as a result of this correction and prophylactic CIED replacement is not recommended, the FDA stated.

Recommendations for Patients and Caregivers

The FDA said there are no actions recommended for patients or caregivers related to this software update or cybersecurity vulnerability.
Consult with your physician for routine care and follow-up.

The FDA reminds patients, patient caregivers, and healthcare providers that any medical device connected to a communications network (for example: wi-fi, public, or home internet) may have cybersecurity vulnerabilities that could be exploited by unauthorized users. However, the increased use of wireless technology and software in medical devices can also offer safer, timely and more convenient healthcare delivery.

For more information — www.medtronic.com/content/dam/medtronic-com/us-en/corporate/documents/REV-Medtronic-2090-Security-Bulletin_FNL.pdf, or contact Medtronic Technical Services at 1-800-638-1991.

FDA Takes Cybersecurity Seriously

Medtronic is the second EP device maker to have an EP recall due to cybersecurity vulnerabilities of its technologies. The first major public discussion of the potential hacking of pacemakers and implantable defibrillator (ICDs) was in 2016 when a business market intelligence firm reported St. Jude Medical's EP technologies could be hacked. The FDA then raised serious concerns over these vulnerabilities. St. Jude Medical was purchased by Abbott during that time. The FDA cleared fixes for Abbott's cybersecurity vulnerabilities in August 2017. 
 

Related Cardiac EP Device Cybersecurity Content:

Heart Rhythm Society Recommends How to Prepare for Cybersecurity Threats to Cardiac Implantable Devices

Raising the Bar for Medical Device Cyber Security

The State of Healthcare Cyber Security

Can Your Cardiac Device Be Hacked?

FDA Announces New Medical Device Safety Action Plan

To extract or abandon broken or infected implantable, venous electrophysiology (EP) device leads has been a debate for more than 20 years. Some EPs argue there is a major risk to patients if old pacemaker or implantable cardioverter defibrillator (ICD) leads are extracted. Heavy scar tissue encases the leads after implant, and rough tugging to pull them out may cause the large veins to tear, which can be catastrophic. Supporters of lead extraction say it is necessary to remove the leads in many patients to prevent venous occlusion or the spread of infection. 

In the past decade, the scales appear to be tipping in favor of lead extraction as the safety for procedure improves. The Heart Rhythm Society (HRS) lead management guidelines updated most recently in 2017, along with new studies on lead extraction, have made many take a closer look at balancing risk versus benefit.

"A critical mass of people are becoming trained and comfortable with the idea, but it is a big investment," explained Bruce Wilkoff, M.D., FHRS, CCDS, director of cardiac pacing and tachyarrhythmia devices at Cleveland Clinic. He also served as the vice chair of the HRS expert consensus statement on cardiovascular implantable electronic device lead management and extraction.

A Brief History of Lead Management

"We started doing lead extraction in the late 1980s, and at first it was just a few people trying to solve some problems, but a lot of people really just thought we were crazy," Wilkoff said.

He explained the first consensus document for lead management was created in the mid-1990s, but there were still few EPs who wanted to take on the potential patient safety risks. "In 2010, we re-did that consensus document, and by that time we had really come to a point when we really had a community of people who accepted it as the thing to do, but no one was really doing this in any volume. However, in the last five to six years it has really taken off. People are starting to become comfortable and they are willing to take on some risk to solve some important problems."

The biggest of these problems include lead infection, because it has an ongoing mortality risk. "We get the impression that infection is something you can cure with antibiotics, but it turns out subsequent 30, 60 and 90 days and subsequent year or two, you have ongoing mortality risk," Wilkoff said. "And if you don't take it out, infection will be universal. So, there is a mandate, you need to take it out when you have infection."

Infection is rare, only occurring in about 2 percent of patients who get an initial lead placement or an upgraded lead, he said, with infection more common with cardiac resynchronization therapy (CRT). 

Increasing Number of Leads in Patients is an Issue

An additional problem with it is faulty or broken leads. Over time, due to constant movement in body, the wires inside the leads can break. EP devices are increasingly being placed in younger patients, and most leads will not last more than 10-20 years. Wilkoff also noted with an increase use of CRT, these devices require several leads, which becomes an issue with how much room there is in the venous system to put more hardware in later during a replacement. 

"So, you have the issue with filling up the venous system with leads, broken leads and issues with venous occlusions, so these are issues we have to take care of," Wilkoff explained. 

Creating a Lead Management Team

Once a center decides lead extraction is a service they want to offer, Wilkoff said it is not something an operator just does, they need training and they need to assemble a team. 

"You have to understand the risks that are involved and it is a collaboration between the nurses, the anesthesiologist, the surgeon, the operator, the echocardiography and the infectious disease expert," he explained. "There are a number of people you need to assemble as a team to work together."

Etiology of Lead Scarring

Soon after most leads are placed in patients there is usually some clotting that forms on them. Over time, this becomes firmer with fibrosis and might even have calcification. Scarring generally occurs any place where the lead touches the endothelium, either in the vein or in the heart.

"There is lead-to-lead scarring, so they become attached to each other, and there is lead-to-vein fibrosis, so this becomes stiffer and stiffer over time," Wilkoff described. 

Use of Lead Management Techniques

The goal of lead extraction procedures is to peel away that fibrosis without tearing the vein. Wilkoff said a cutting sheath is used to release the lead from scar tissue all the way to the heart before attempting to tug on it to pull it out of the body. 

A stylet is used to increase the tensile strength of the lead so if you are pulling it from the outside, then the whole lead comes together so it does not stretch and pull apart. 

The second tool is a set of telescoping sheaths. These have a hollow lumen and are placed over the lead, using a guidewire to follow the course of the lead and only cut the tissue that is immediately touching the lead. These come in a set of two flexible plastic sheaths that have a beveled cutting edge to separate the lead from the surrounding tissue using manual rotation of the sheath. Wilkoff said today, it is more common to see use of a mechanical version of this system, where a small, circular, rotary cutting blade is actuated with a pistol grip trigger mechanism. These devices are offered by Cook Medical and Spectranetics, which is now part of Philips Healthcare. 

Spectranetics also has an FDA-cleared excimer laser sheath system to cut through tissue to release the leads.

Potential Complications of Electrophysiology Device Lead Extraction

One of the biggest safety concerns in removing old device leads is the possibility of tearing the superior vena cava (SVC). This requires immediate emergency surgical repair to stop the bleeding and the complication currently has a 50 percent mortality rate.

"Most of the time lead extraction works out really well, and in 98 percent of cases there are no major complications," Wilkoff said. "But, in 1.5 to 2 percent range there can be a tear to the venous system or the heart and cause a surgical emergency."

Unfortunately, he said you cannot tell which patients will do well and which will not, so you always need to be ready. This is why it is so important to have clear coordination with an echocardiography and a surgeon on a team in case there is tear that need immediate open surgical repair. 

Increasing the Safety of Lead Extractions

The most serious location to get a tear is the SVC, Wilkoff explained. "A laceration in the SVC is what can cause the most problems," he stressed. "If it bleeds into the chest is will cause a hemothorax, or into the pericardium, causing a pericardial tamponade. If it starts bleeding there, it goes very quickly and opening up a person's chest in time is very difficult."

However, with the introduction of the Spectranetics Bridge Occlusion Balloon in 2016, the there is a new level of safety that can be achieved. It offers a safety net during procedures, allowing rapid inflation of an intravascular balloon to seal the tear and allow the surgical team time to prep and perform a repair without fear of the patient bleeding out. The device was credited with saving about 20 lives in the first year after gaining market clearance. 

A guidewire is placed prior to the procedure through the femoral vein to the SVC. If needed, the balloon is advanced up the wire and is inflated using iodine contrast so it can clearly be seen on angiography. The balloon seals the tear and makes it much easier for the surgeon to see and make the repair.

Setting Standards for Lead Management Centers

Lead extraction procedures now number in the tens of thousands per year, but Wilkoff said standards need to be set. This is now included as part of the most recent 2017 revision of the HRS consensus document on lead management. 

"Everybody should be able to tell their patients how many of these procedures they do, what there success rate is and what their complication rate is," Wilkoff said. 

He noted the European Lead Extraction ConTRolled (ELECTRa) registry showed performance of centers performing 30 or more extractions a year were better than centers performing fewer than 30 per year.[2] As with any procedure, the more a center does, the better they become, he explained. "Our previous estimates that 20 procedures a year was good might be too low, which tells us that people who want to do this really need to make a commitment to do this or don't do it at all," Wilkoff said. 

New 2017 HRS Expert Consensus on Lead Management and Extraction

In September 2017, the HRS published an updated Expert Consensus Statement on Cardiovascular Implantable Electronic Device Lead Management and Extraction.

It was developed in collaboration with the American College of Cardiology (ACC), American Heart Association (AHA), Asia Pacific Heart Rhythm Society (APHRS), American Society of Anesthesiologists (ASA), European Heart Rhythm Association (EHRA), Infectious Diseases Society of America (IDSA), Latin American Heart Rhythm Society (LAHRS), Pediatric and Congenital Electrophysiology Society (PACES) and Society of Thoracic Surgeons (STS). It is intended to help clinicians in their decision-making process for managing leads and builds on the 2009 Transvenous Lead Extraction: Heart Rhythm Society Expert Consensus on Facilities, Training, Indications and Patient Management document. It provides practical clinical guidance in the broad field of lead management, including lead extraction.

The document features a clinician summary and a pocket card. It is available across multiple platforms, including print, electronic media, and the Guideline Central mobile app at www.guidelinecentral.com.

The statement focuses on identifying the presence of lead malfunction, deciding on whether to abandon or to extract a lead that is no longer clinically necessary or at higher risk for failure, offering guidance on whether a cardiovascular implantable electronic device (CIED) is involved in an infectious process, providing recommendations on when lead extraction should be considered, and discussing specific clinical considerations for patient management when a lead extraction is performed.

The document includes specific recommendations in the following areas: 
   • Lead Survival
   • Existing CIED Lead Management
   • Indications for Lead Extraction (Infectious)
   • Indications for Lead Extraction (Noninfectious)
   • Outcomes and Follow-up

Expanding Lead Management Training via the Web

A few years ago, in an effort to expand lead extraction training to a greater audience, Wilkoff and others created a an online group called LeadConnection.org. The goal was to reduce the economic barriers to getting training for EP operators who cannot attend the annual HRS or other larger EP meetings. The site includes a collection of all the literature on lead management, cases and offers a platform for sharing communication. The group also offers debates and webinars. 

Related Lead Management Content:

Dr. Bruce Wilkoff Explains His Lead Management Learnings Over 20+ Years

Study Shows Occlusion Balloon Saves Lives During Lead Extraction

VIDEO: EP Lead Extraction Strategies — Interview with Bruce Wilkoff, M.D.

VIDEO: Demonstration of How the Bridge Occlusion Balloon Seals SVC Tears

Advances in Transvenous Lead Extraction — Article by Avi Fischer, M.D., FACC, FHRS

Strategies, New Technologies Aid Lead Management.

References:

1. Kusumoto F.M., Schoenfeld M.H., Wilkoff B.L., et al. 2017 HRS expert consensus statement on cardiovascular implantable electronic device lead management and extraction. Heart Rhythm. 2017 Dec;14(12):e503-e551. doi: 10.1016/j.hrthm.2017.09.001. Epub 2017 Sep 15.

2. Bongiorni M.G., Kennergren C., Butter C., et al. The European Lead Extraction ConTRolled (ELECTRa) study: a European Heart Rhythm Association (EHRA) Registry of Transvenous Lead Extraction Outcomes. Eur Heart J. 2017 Oct 21;38(40):2995-3005. doi: 10.1093/eurheartj/ehx080.

March 22, 2019 — The U.S. Food and Drug Administration (FDA) issued a safety communication to alert healthcare providers and patients about the cybersecurity vulnerabilities identified in a wireless telemetry technology used for communication between Medtronic’s implantable electrophysiology (EP) cardiac devices, clinic programmers and home monitors. 

The FDA said a wireless telemetry protocol used for communication between the devices and their programming and monitoring systems has cybersecurity vulnerabilities because it does not use encryption, authentication or authorization. The FDA said this makes these system easy to hack into.

The FDA said although the system’s overall design features help safeguard patients, Medtronic is developing updates to further mitigate these cybersecurity vulnerabilities. To date, the FDA is not aware of any reports of patient harm related to these cybersecurity vulnerabilities. The FDA also recommends that healthcare providers and patients continue to use these devices as intended and follow device labeling.

The alert concerns Medtronic’s implantable cardioverter defibrillators (ICDs) and cardiac resynchronization therapy defibrillators (CRT-Ds), devices that provide pacing for slow heart rhythms and electrical shocks or pacing to stop dangerously fast heart rhythms. The safety notice does not include any pacemakers, cardiac resynchronization pacemakers (CRT-Ps), CareLink Express monitors, or the CareLink Encore Programmer (model 29901).

ICDs and CRT-Ds are implanted under the skin in the upper chest area with connecting insulated wires called leads that go into the heart. A patient may need an ICD or CRT-D if their heartbeat is too slow (bradycardia), too fast (tachycardia), or needs coordination to treat heart failure. The Medtronic CareLink Programmer (model 2090) is used during the implantation and regular follow-up visits for Medtronic ICDs and CRT-Ds.

The MyCareLink Monitor (models 24950 and 24952) is used to wirelessly connect to the patient's implanted cardiac device and read the data stored on the device. The transmitter, located in the patient's home, sends the patient's data to his or her physician(s) by the CareLink Network using a continuous landline, cellular, or wireless (wi-fi) Internet connection.

EP Devices Included in the Safety Alert

Affected Medtronic ICD and CRT-D device models included in the FDA safety alert are:
  • Amplia MRI CRT-D, all models
  • Claria MRI CRT-D, all models
  • Compia MRI CRT-D, all models
  • Concerto CRT-D, all models
  • Concerto II CRT-D, all models
  • Consulta CRT-D, all models
  • Evera MRI ICD, all models
  • Evera ICD, all models
  • Maximo II CRT-D and ICD, all models
  • Mirro MRI ICD, all models
  • Nayamed ND ICD, all models
  • Primo MRI ICD, all models
  • Protecta CRT-D and ICD, all models
  • Secura ICD, all models
  • Virtuoso ICD, all models
  • Virtuoso II ICD, all models
  • Visia AF MRI ICD, all models
  • Visia AF ICD, all models
  • Viva CRT-D, all models

Affected Medtronic Programmer and Monitors models include:
  • CareLink 2090 Programmer
  • MyCareLink Monitor, models 24950 and 24952
  • CareLink Monitor, Model 2490C

Wireless Telemetry Protocol is Main Problem

The FDA said it reviewed information concerning potential cybersecurity vulnerabilities associated with the use of the Conexus wireless telemetry protocol which is used as part of the communication method between Medtronic’s ICDs, CRT-Ds, clinic programmers and home monitors. The Conexus wireless telemetry protocol uses wireless radio frequency (RF) to enable communication between the devices 

The wireless system allows Medtronic programmers and monitoring accessories to do one or more of the following:
   • Remotely transmit data from a patient’s implanted cardiac device to a specified healthcare clinic (remote monitoring), including important operational and safety notifications;
   • Allow clinicians to display and print device information in real-time; and
   • Allow clinicians to program implanted device settings.
   
The FDA said the Conexus wireless telemetry protocol has cybersecurity vulnerabilities because it does not use encryption, authentication, or authorization. The FDA has confirmed that these vulnerabilities, if exploited, could allow an unauthorized individual to access and potentially manipulate an implantable device, home monitor or clinic programmer.

Medtronic is working to create and implement additional security updates to address these cybersecurity vulnerabilities beyond safety features in the current design as described in Medtronic’s security bulletin. For example, the safety features in the current design include a protocol that be activated only by the patient’s healthcare provider at a clinic. Activation times vary by patient, and an unauthorized user would need to be close to an active device, monitor or clinic programmer to take advantage of these vulnerabilities, the FDA said. 

For more information see Medtronic’s Security Bulletin.

Recommendations for Healthcare Providers

The FDA said providers should continue to use the CareLink programmers for programming, testing and evaluation of ICD and CRT-D patients. There is no programmable setting that allows a clinician to turn off the Conexus wireless capabilities in the affected devices.

Providers should maintain control of CareLink programmers within your facility at all times according to your hospital information technology (IT) policies.

The FDA said providers should only use home monitors, programmers and implantable devices obtained directly from the manufacturer to ensure integrity of the system.

Providers also should remind patients to keep their home monitors plugged in. The FDA said the benefits of remote wireless monitoring of an implantable device outweigh the practical risk of an unauthorized user exploiting of these devices’ vulnerabilities. The monitor also must remain powered on to ensure timely transmission of any wireless CareAlerts programmed by the physician, and to ensure automatically-scheduled remote transmissions occur at the specified time.

Providers should operate the programmers within well-managed IT networks. The FDA recommends consulting with IT departments regarding the security of the network. For recommended actions to better secure a computer network environment, refer to www.nist.gov/cyberframework.

The FDA said reprogramming or updating the affected devices is not required at this time.

Prophylactic ICD or CRT-D replacement is not recommended and should not be performed to solely address this vulnerabilities, the FDA warned.

As with any connected medical device and especially implanted life-supporting or life-sustaining devices, discuss the risk of cybersecurity vulnerabilities with patients prior to implanting ICDs and CRT-Ds, along with other device risks and benefits, and take advantage of the latest software updates and improvements to devices.

Recommendations for Patients and Caregivers

To date, the FDA is not aware of any reports of patient harm related to these cybersecurity vulnerabilities.

The FDA recommends that patients and caregivers take the following actions:  
   • Use only remote monitors obtained directly from your healthcare provider or the manufacturer to ensure integrity of the system.
   • Continue to keep the remote monitor plugged in at all times to ensure any wireless CareAlerts programmed by your health care provider and any automatically-scheduled remote transmissions occur in a timely manner.
   • Keep track of your remote monitor.
   • Get medical help right away if you feel lightheaded, dizzy, lose consciousness, or have chest pain or severe shortness of breath.
   • Contact Medtronic Technical Services Monday through Friday 7 a.m. – 6 p.m. central time at (855) 275-2717 for additional information, or if you have any questions regarding the vulnerabilities.

FDA Monitoring Situation and Working With the Vendor

The FDA is working with Medtronic while they create and implement additional security updates to address these cybersecurity vulnerabilities and improve patient safety and will inform the public as new information is available.

The FDA urges manufacturers everywhere to remain vigilant about their products — companies should take steps to monitor and assess cybersecurity vulnerability risk, and be proactive about disclosing vulnerabilities and mitigations to address them. This is part of the FDA’s overall effort to collaborate with manufacturers and healthcare delivery organizations—as well as security researchers and other government agencies—to develop and implement solutions to address cybersecurity issues throughout a device’s total product lifecycle. The FDA issued recommendations to manufacturers for continued monitoring, reporting, and remediation of medical device cybersecurity vulnerabilities.

Read the full FDA safety alert.

Related Cardiac EP Device Cybersecurity Content:

FDA Says Medtronic is Updating Cybersecurity Vulnerabilities of its Implantable Cardiac Device Programmers

Heart Rhythm Society Recommends How to Prepare for Cybersecurity Threats to Cardiac Implantable Devices

Raising the Bar for Medical Device Cyber Security

The State of Healthcare Cyber Security

Can Your Cardiac Device Be Hacked?

FDA Announces New Medical Device Safety Action Plan

April 18, 2019 – Biotronik announced the European market release of what it calls the world’s smallest implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy defibrillator (CRT-D) devices that are approved for 3T full-body magnetic resonance imaging (MRI) scans.1

Devices in the Acticor and Rivacor families are only 10 mm slim, with a smooth and elliptical BIOshape that facilitates the insertion procedure. “The slenderness and smoother shape of the new devices play a key role in easing the insertion procedure and improving how the device looks after implantation,” reported Iain Matthews, M.D., Northumbria Healthcare, U.K., following his first implantations of the devices. More than 90 percent of implanting physicians rated “patient comfort” as “better” or even “much better” in comparison with previous models during post-market observation.2

Besides their body-friendly shape, Acticor and Rivacor devices feature an extended battery life, with up to 15 years for ICDs3 and nine years for CRT-Ds4. Increased device longevity is designed to lower the need for device replacements, resulting in reduced risks5, less distress for patients and fewer procedure costs. The new range of devices are also supported by a fully warranty of 10 years for ICDs and six years for CRT-Ds.

With Biotronik Home Monitoring, cardiovascular data from an Acticor or Rivacor device can be transmitted to the physician on a daily basis with programmable alerts about relevant changes in patient health and device status. The IN-TIME randomized controlled trial has demonstrated more than 60 percent reduction in all-cause mortality when CRT-Ds are used with Biotronik Home Monitoring.6 In ICDs, Home Monitoring has been clinically proven to help physicians detect atrial fibrillation earlier7, as well as reduce the number of inappropriate shocks by 90 percent and related hospitalization rates by 73 percent8. Biotronik Home Monitoring’s new QuickCheck feature gives access to patient data typically within three to four minutes.9

The typical non-response rate of 30-40 percent of all patients is a major problem in CRT.10,11 To counter this, Acticor and Rivacor CRT-Ds feature CRT AutoAdapt to fit patients’ individual pacing needs and provide continuous CRT adaptation – automatically adjusting to changes sensed in a patient’s condition every minute. Auto LV VectorOpt further helps to evaluate clinically relevant pacing parameters, with automatic threshold measurements across 20 vectors12 in less than 2.5 minutes13 and rapid direct programming.

All Acticor and Rivacor devices feature ProMRI, giving patients full access to high-resolution 3T MRI without any exclusion zone. With sensor-based MRI AutoDetect technology, once activated for a programmable window of up to 14 days, the devices can automatically recognize an MR environment and switch in and out of MRI mode as required. This ensures that patients receive optimal therapy, with tachycardia therapy suspension limited to the duration of the MRI scan, as well as fewer in-office visits required for device programming. Acticor and Rivacor devices also feature DX technology, enabling complete atrial diagnostics without an atrial lead.

For more information: www.biotronik.com

References

1. As part of an MR conditional system.

2. Post-Market observation; final-report, March 1, 2019. Data on file.

3. Acticor/Rivacor VR-T Standard conditions. 15.4 years @ 40 ppm; 0% pacing @ 2.5V/0.4ms; 500 Ohms; 2 max. energy shock/year. Data on file.

4. Acticor/Rivacor HF-T QP, 9.3 years @ 60 ppm; RA 15%, RV/LV 100% pacing, RA/RV/LV @ 2.5 V/0.4 ms; 500 Ohms, 2 max. energy shocks/year. Data on file.

5. Polyzos KA et al. Europace. 2015, 17(5).

6. Hindricks G et al. The Lancet. 2014, 384(9943).

7. Varma N et al. Circulation. 2010, 122(4).

8. Guedon-Moreau L et al. J Cardiovasc Electrophysiol. 2014, 25(7).

9. Performance analysis. Data on file.

10. Daubert C et al. Eur Heart J. 2017, 38(19).

11. Auricchio A et al. J Am Coll Cardiol. 2008, 51(15).

12. QP models only.

13. Post-Market observation; final report, March 1, 2019. Data on file.

April 29, 2019 — Biotronik announced the full commercial launch of the Acticor device family, including Acticor DX and CRT-DX devices. Electrophysiologists throughout the United States are now treating patients with the new implantable cardioverter defibrillators (ICDs) and cardiac resynchronization therapy defibrillators (CRT-Ds).

When implanted with Biotronik's Plexa ProMRI S DX lead, the hybrid ICD Acticor systems offer dual-chamber diagnostics without the need for an atrial lead. Importantly, all three Acticor DX devices feature a new DF4 header configuration with a penta-polar electrode lead cable design that simplifies the implant procedure for physicians.

Larry Chinitz, M.D., and Lior Jankelson, M.D., Ph.D., New York, N.Y.; and Chafik Assal, M.D., Charleston, W.Va.; are among the first in the country to treat patients with Acticor.

"Smaller device systems with greater diagnostic capabilities and longer battery life improve how we treat patients," said George Thomas, M.D., New York, N.Y. "The new Acticor DX devices offer a simplified DF4 lead connection for the DX system. In my first cases, the slimmer, smoother device fit more easily in the pocket and substantially improved patient comfort post-op. These features bring clinical value and enhance patient quality of life."

Biotronik's unique DX technology enables the detection of silent atrial fibrillation; this helps prevent stroke, enhances diagnostic accuracy to improve clinical decision-making and allows for supraventricular tachycardia (SVT) discrimination to prevent unnecessary shocks. By reducing the number of leads, procedure times are faster and costs and complications are decreased.

The U.S. Food and Drug Administration (FDA) approved Acticor DX, Acticor CRT-DX Bipolar and Acticor CRT-DX in March, along with the Rivacor device family for the treatment of tachycardia and heart failure. Acticor and Rivacor are the smallest and slimmest cardiac rhythm management (CRM) devices approved for use in full-body, 3 Tesla (3T) magnetic resonance imaging (MRI) scans, according to the company. The new devices measure just 10 mm thin, with a smooth, rounded BIOshape that eases implantation and increases patient comfort. The devices have improved battery longevity — nearly 15 years for Rivacor VR-T, 13.5 years for Rivacor DR-T, 14 years for Acticor DX, and 11 years for both Rivacor CRT and Acticor CRT-DX. They are backed by extended device warranties.

Read the article "FDA Approves 3T Acticor and Rivacor Tachycardia Devices from Biotronik"

The ultraslim Acticor and Rivacor device systems feature MRI AutoDetect, Closed Loop Stimulation and Biotroink Home Monitoring. As a result, they provide more efficient MRI access, individualized physiological rate response and remote monitoring that is proven to reduce all-cause mortality in heart failure patients by more than 60 percent

For more information: www.biotronik.com

May 13, 2019 – A first-in-human pilot study of Medtronic's investigational Extravascular Implantable Cardioverter Defibrillator (EV ICD) system showed it can be implanted with no major complications, and can sense, pace and defibrillate the heart. Results from the pilot study were presented during a late-breaking session at Heart Rhythm 2019, the Heart Rhythm Society's 40th Annual Scientific Sessions.

The device uses a lead is placed outside of the heart and veins to deliver lifesaving defibrillation and anti-tachycardia pacing therapy in one system, with a device the same size as traditional, transvenous ICDs. The EV ICD system is investigational worldwide and not approved for sale anywhere.

"I am very encouraged by our pilot experience using the Medtronic EV ICD system in patients out to three months,” said Ian Crozier, M.D., Department of Cardiology, Christchurch Hospital, Christchurch, New Zealand, and principal investigator (PI) in the pilot study. “This small but important study affirms the potential of this new extravascular approach to provide pacing and lifesaving defibrillation therapy without the risks that accompany transvenous leads implanted inside the heart and veins.”

In the pilot study, 21 patients underwent the EV ICD implant procedure at four sites in New Zealand and Australia. Patients were evaluated at implant, two weeks, four to six weeks, and three months after device implant, and continue to be followed. Study investigators characterized the safety of the system and implant procedure, defibrillation effectiveness and sensing and pacing:
   • At the time of implant, defibrillation testing was completed on 19 patients. The system successfully terminated induced ventricular arrhythmias in 17 patients (89.5 percent), which is consistent with prior clinical studies of existing ICDs.[1,2]
   • Pacing capture was achieved in more than 95 percent of study patients.
   • One patient experienced ventricular tachycardia outside the hospital setting, which was successfully detected and treated by the EV ICD system.

“The successful pilot study revealed valuable insights to inform our EV ICD clinical program, and we are eager to incorporate the learnings from this study into a pivotal trial,” said Rob Kowal, M.D., Ph.D., vice president and chief medical officer of the cardiac rhythm and heart failure division at Medtronic. 

The Medtronic EV ICD system is intended to provide the benefits of traditional, transvenous ICDs including lifesaving defibrillation therapy; anti-tachycardia pacing to terminate arrhythmias; post-shock pacing to protect from sudden cardiac death; and temporary, back-up, bradycardia pacing to address abnormally slow heart rates. It is the same size (33 cc) and shape, and is expected to have similar longevity as traditional ICDs, but without any leads in the veins or heart. The EV ICD device is implanted in the left mid-axillary region below the left armpit, and the lead is placed under the sternum (breastbone). New procedure tools guide the delivery of the system.

Medtronic research teams developed the EV ICD System and have completed multiple early research and acute feasibility studies, including the ASD3 (Acute Sensing and Defibrillation), SPACE[4] (Substernal Pacing Acute Clinical Evaluation), and ASD2[5] studies. The current EV ICD pilot study continues to generate long-term data on this first-inhuman experience.

Related Content:

Medtronic Begins Pilot Study of Investigational Extravascular ICD System

Medtronic Study Confirms Feasibility of New Extravascular Approach to ICD Therapy

All the HRS 2019 late-breaking studies 

Link to other HRS 2019 news

References:

1. Blatt JA, Poole JE, Johnson GW, et al. No benefit from defibrillation threshold testing in the SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial). J Am Coll Cardiol. 2008 Aug 12;52(7):551-6.
2. Neuzner J, Hohnloser SH, Kutyifa V, et al. Effectiveness of single- vs. dual-coil implantable defibrillator leads: An observational analysis from the SIMPLE study. J Cardiovasc Electrophysiol. 2019 Apr 4. doi: 10.1111/jce.13943.
3. Chan JYS, Lelakowski J, Murgatroyd FD et al. Novel Extravascular Defibrillation Configuration With a Coil in the Substernal Space: The ASD Clinical Study. J Am Coll Cardiol EP 2017;3:905-10.
https://doi.org/10.1016/j.jacep.2016.12.026
4. Sholevar DP, Tung S, Kuriachan V, et al. Feasibility of extravascular pacing with a novel substernal electrode configuration: The Substernal Pacing Acute Clinical Evaluation Study. Heart Rhythm. Published online 29Nov2017. DOI:http://dx.doi.org/10.1016/j.hrthm.2017.11.030.
5. Boersma, LVA. Feasibility of Extravascular Pacing, Sensing And Defibrillation From A Novel Substernal lead: The Acute Extravascular Defibrillation, Pacing And Electrogram (ASD2) Study. Presented Heart Rhythm Society Scientific Sessions, May 11, 2018.

May 13, 2019 – Results from a new survey are the first to report a large discrepancy in patient’s knowledge of their cardiac implantable electronic device (CIED). The study reviewed patients’ overall knowledge of data from their devices as well as their perceptions on what is most important. Participants in this study have a strong desire to better understand their device and its data, with more guidance on battery life as the most important aspect for patients. The study was presented at Heart Rhythm 2019, the  Heart Rhythm Society's 40th Annual Scientific Sessions.

In the United States, cardiac arrhythmias impact an estimated 14.4 million patients.[1] Today, CIEDs have evolved to be a prevalent treatment option for these patients, with more than 300,000 individuals receiving new CIED implants every year in the U.S. alone.[2] As new technology innovations emerge, patients have greater or unprecedented access to real-time data and information about their health from their devices. With advancing technology and increasing use of CIEDs, there is a need to better understand patients' knowledge of their devices and their perceptions of what data elements are most important.

The study initially screened 400 patients between July and December 2018 who attended an in-person device evaluation at the Cleveland Clinic outpatient clinic. The mean patient age was 62.9±12.8 years and 64 percent were male. Patients received a one-page questionnaire asking multiple choice questions in seven basic categories: type of CIED, original indication, functionality, manufacturer, number of active leads, estimated battery life, and number of shocks. Their answers were then compared to their interrogation report to assess accuracy. Patients were also asked to share what data would be most important to them as the device user.

"Our research uncovered a discrepancy between patients’ perception of their own knowledge of their devices and their actual knowledge about their device. While some patients have lived with these devices for years, our results show that there is still a general lack of knowledge," said lead author Divyang Patel, M.D., Cleveland Clinic. "As digital health evolves, patients are able to access their own health data in real-time. By equipping device users to be active participants in their health, we hope they will be able to utilize their own data and be empowered to be more engaged in their care and live a healthier life."

In this cohort, 344 or 86 percent of patients agreed to take the survey. From this group, 62 percent agreed or strongly agreed that they were knowledgeable about their device, however, 84 percent missed at least one question. 48 percent of survey participants missed at least two questions about their device. Patients agreed or strongly agreed that they had a desire to have more information regarding each of the following: battery life (81 percent), activity level (76 percent), heart rate trend (73 percent) and ventricular arrhythmias (71 percent). The results of this study show a discrepancy in patients’ knowledge regarding their CIEDs and their wish to better understand the device.

"Despite the advancement in remote monitoring of CIEDs, up until recently it has been a process between clinicians and manufacturers, with patients on the receiving end. Now that patients have access to data in real-time, especially with the advancement of digital health technologies and increased use of smart devices, we need to help guide patients, clinicians, and manufacturers on how to make the most out of their information to help advance patient care and lead to positive outcomes," said senior author Khaldoun Tarakji, M.D., MPH, FHRS, Cleveland Clinic. "Our study is one of the first to give insight into the voice of the patient and what they desire to know. Now, the physician community along with device manufacturers and medical societies need to work together on a plan for optimal education and success."

All the HRS 2019 late-breaking studies 

Link to other HRS 2019 news

References:
1. Roger VL, Go AS, Lloyd-Jones DM, et al. American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Heart disease and stroke statistics—2011 update: a report from the American Heart Association. Circulation 2011;123:e18-e209.
2. Greenspon A.J., Patel J.D., Lau E., et al. (2011) 16-year trends in the infection burden for pacemakers and implantable cardioverter-defibrillators in the United States 1993 to 2008. J Am Coll Cardiol 58:1001–1006.

May 13, 2019 — Boston Scientific announced acute results from the UNTOUCHED study evaluating safety and efficacy of the Emblem subcutaneous implantable defibrillator (S-ICD) system for primary prevention of sudden cardiac death specifically in patients with a left ventricular ejection fraction (LVEF) ≤35 percent. This is the most common population to be indicated for ICD therapy. The results demonstrated S-ICD therapy had a complication-free rate of 95.8 percent at 30 days post-procedure and high conversion efficacy (99.2 percent) of induced ventricular fibrillation, rates comparable to those seen in previous S-ICD and transvenous implantable cardioverter-defibrillator (TV-ICD) studies.

The data were presented during a late-breaking clinical trial at Heart Rhythm 2019, the Heart Rhythm Society's 40th Annual Scientific Sessions, May 8-11 in San Francisco. The analysis was also published online in the Heart Rhythm Journal.[1]

The UNTOUCHED study authors also reviewed procedure techniques and 30-day outcomes in patients implanted with the Emblem S-ICD System and found that the majority (69 percent) of procedures were performed using a two-incision technique. The two-incision technique data demonstrated a mean implant time of 55.8 minutes, which was 8 minutes faster than the mean 63.8 minutes for procedures that leveraged a three-incision implant technique, with comparable complication and conversion success rates.  

"We found that the complication rate within this primary prevention population was as low as in prior S-ICD registries, despite the patients having much lower LVEF, more hypertension and diabetes – underscoring that sicker patients do well with this device for the prevention of sudden death," said Lucas V.A. Boersma, M.D., Ph.D., study principal investigator and electrophysiologist at St. Antonius Hospital, the Netherlands. "These acute outcomes also validate the advantages of the two-incision implant technique, which has continued to gain worldwide adoption in the last few years."

Watch the VIDEO: Overview of Subcutaneous ICD Technology, an interview with Boersma.

The global, prospective, non-randomized study evaluated data from 1,116 patients with a low LVEF, the majority of whom (54 percent) had ischemic heart disease.

The final results of the UNTOUCHED study, including an analysis comparing inappropriate shock rates of the S-ICD to rates found in previous TV-ICD studies, will be reported after 18-months of patient follow-up.  

Read the article "Subcutaneous ICD System Shows Positive Outcomes in Largest Real-world Study"

For more information: www.bostonscientific.com

All the HRS 2019 late-breaking studies 

Link to other HRS 2019 news

Reference

1. Boersma L.V., El-Chami M.F., Bongiorni M.G., et al. Understanding Outcomes with the S-ICD in Primary Prevention Patients with Low EF Study (UNTOUCHED): Clinical characteristics and perioperative results. Heart Rhythm Journal, published online May 10, 2019. https://doi.org/10.1016/j.hrthm.2019.04.048

May 14, 2019 – Results from new research show that passengers with cardiac implantable electronic devices (CIEDs), such as pacemakers or implantable cardioverter defibrillators (ICDs), can safely travel through airport security checkpoint scanners. This is the first study to look at the relationship between body scanners and the impact on functionality of devices. The results were presented at Heart Rhythm 2019, the Heart Rhythm Society's 40th Annual Scientific Sessions and show no negative interference after analyzing more than 1,000 scans.

More than 3 million people across the world have pacemakers, a common CIED, as treatment for abnormal heart rhythms.[1] Body scanners are increasingly being used worldwide and are replacing conventional metal detectors. These scanners represent a potential new source of electromagnetic interference (EMI). EMI is a disturbance known to cause pacing inhibition or inappropriate shock therapy. Patients are advised to manage this potential risk by limiting their exposure to certain technologies including metal detectors, magnets, MRI scans and other medical procedures.

Prior to conducting the study, the authors surveyed more than 1,000 patients and found that 80 percent have fears or concerns about passing through body scanners at the airport. The survey information further reinforces the need to clarify the safety of airport security body scans for passengers with CIEDs.

The study included 375 patients enrolled between May 2017 and October 2018. The devices studied included implantable cardioverter defibrillators (ICD) (n=175, 47 percent), conventional pacemakers (PM) (n=127, 33 percent), subcutaneous ICD (S-ICD) (n=52, 14 percent), and leadless pacemakers (LCP) (n=21, 6 percent). The sensitivity levels of the devices were not altered, ICD shock therapy was disabled and permanent ventricular pacing were ensured to facilitate the detection of EMI. The primary endpoint was EMI events including pacing inhibition, upper rate tracking, tachycardia detection and spontaneous reprogramming. The secondary endpoint was the incidence of CIED detection by the body scanner.

Results from more than 1,000 body scans reported no interference with patient devices. There were no events of EMI during the body scans across 375 devices. Further, no CIEDs were detected by the body scanners (EMI-prevalence 0 percent [95 percent CI; 0 percent 1 percent]).

"We were surprised to learn that so many patients expressed concerns about the functionality of their devices while travelling. We wanted to help put their minds at ease by testing the potential interference body scanners could have on common devices like pacemakers and defibrillators," said lead author, Carsten Lennerz, M.D., MSci, German Heart Centre Munich. "Our study results show that now patients can travel worry-free knowing they can safely go through security checkpoints without the need of disclosing personal medical information."

The authors place importance on studies with larger patient populations and different types of body scanners. In addition, the studied the possible interference between devices and electric cars. "Do Electric Cars Impact Pacemakers and Defibrillators?" is also being presented at the meeting.

Read the related article "Driving a Tesla Car Does Not Cause Defibrillator Shocks."

All the HRS 2019 late-breaking studies 

Link to other HRS 2019 news

Reference:
1. Wood, M. A., & Ellenbogen, K. A. (2002). Cardiac Pacemakers From the Patient’s Perspective. Circulation, 105(18), 2136-2138. doi:10.1161/01.cir.0000016183.07898.90

May 15, 2019 - Three new studies show that patients who are medically indicated for implantable heart devices, including implantable cardioverter defibrillators (ICDs) and cardiac resynchronization therapy (CRT), often do not receive needed therapy. The findings underscore gender and race treatment disparities, as well as a lack of referrals to physicians to implant the devices. Presented at Heart Rhythm 2019, the Heart Rhythm Society's 40th Annual Scientific Sessions, the analyses were supported by Medtronic and used Optum Electronic Health Records (EHR) datasets and algorithms developed as part of the Medtronic GLIDE HF (GuideLine Indications Detected in EHR for HF) initiative.

“Device usage across both gender and race was strikingly low, despite medical records documenting patient eligibility for the therapy,” said Anne B. Curtis, M.D., study author and SUNY Distinguished Professor of Medicine in the Jacobs School of Medicine and Biomedical Sciences at the University at Buffalo, Buffalo, N.Y. “The breadth of practice type – from academic medical centers to community hospitals – along with the sheer number of patients highlight the seriousness of the challenge.”

ICDs have been saving lives for more than 30 years by delivering a lifesaving shock or painless pacing to stop life-threatening fast or irregular heartbeats. Cardiac resynchronization therapy is a treatment for heart failure that uses an implantable device to improve the pumping efficiency of the heart; the device can be a CRT-pacemaker (CRT-P) or CRT-defibrillator (CRT-D). Typically, these devices are implanted by electrophysiologists, cardiologists who specialize in identifying and treating heart rhythm disorders, after patients are referred by general practitioners or general cardiologists.

Treatment Disparities Across Gender and Race

A real-world assessment of disparities among people indicated for the therapies, based on medical society guidelines, found that:
   • Devices were implanted more frequently in indicated men than women (16.7 percent and 12.7 percent, respectively), but were significantly underused in all patient populations.
   • In the analysis, both women and men of color and white women received devices at lower rates than white men. 

This analysis of EHR data from more than 1 million patients is consistent with previous research showing that black patients are considerably less likely to receive cardiac interventions.

Implantable Device Underutilization

The real-world analysis using electronic health record (EHR) data looked at the utilization rates of device therapies in heart failure patients as defined by medical society (ACCF/AHA/HRS) guidelines. The analysis showed that ICDs and CRT-Ds are substantially underutilized compared to other cardiovascular interventions, such as imaging, drug therapies and coronary procedures. Less than one-third (32.3 percent) of eligible patients received CRT, and 11.0 percent of eligible patients received ICDs. 

The analysis showed consistent underutilization trends across five years (2012-16) in more than 100,000 patients, adding to the existing research that has previously highlighted treatment gaps. The impact of the 2012 guidelines (ACCF/AHA/HRS Focused Update for Device-based Therapies of Cardiac Rhythm Abnormalities) had not been thoroughly studied previously.

Access to Electrophysiologists

A separate analysis of EHR data assessed referral and implant patterns among ICD-indicated patients. The analysis revealed that half (50.5 percent) of ICD-indicated patients were referred to an electrophysiologist. Patients referred to and seen by an electrophysiologist were more likely to receive ICDs. About 44.3 percent of patients seen by an electrophysiologist received a device, according to the study. Among patients who did not see an electrophysiologist, only 8.8 percent received a device.

“While each of these analyses evaluated different aspects of implantable cardiac device use, the unifying theme is that far too many patients are not getting all of the therapies that could provide them with significant benefit,” said Rob Kowal, M.D., Ph.D., vice president and chief medical officer of the cardiac rhythm and heart failure division at Medtronic. “Implantable defibrillators and CRT-Ds are life-saving devices, so there is a clear need to address barriers to proper care for indicated patients.”

In collaboration with leading clinicians, researchers and scientists worldwide, Medtronic offers the broadest range of innovative medical technology for the interventional and surgical treatment of cardiovascular disease and cardiac arrhythmias. The company strives to offer products and services of the highest quality that deliver clinical and economic value to healthcare consumers and providers around the world.

For more information: www.medtronic.com

All the HRS 2019 late-breaking studies 

Link to other HRS 2019 news

Related Content:

Study Reveals Racial Gender Disparities in Care for New Atrial Fibrillation Patients

Nearly All ICD Implants Performed on Insured Patients

Disparities Found in Standard of Cardiac Care for Heart Valve Disease in Minorities

Women, Blacks Face Larger Loss of Life Expectancy After Heart Attack

May 15, 2019 — A new infection risk scoring system has been developed based on data from the large PADIT Trial.[1] The new scoring system was presented as a follow up to that study during a late-breaking session at Heart Rhythm 2019, the Heart Rhythm Society's 40th Annual Scientific Sessions.

"We developed a novel infection risk score in the largest cardiovascular implantable electronic device (CIED) trial to date, with five independent predictors that are readily adopted into clinical practice," explained Andrew D.. Krahn, M.D., FHRS, professor in the Division of Cardiology at the University of British Columbia, who presented the study. He said the PADIT infection score warrants validation in an independent cohort study.

CIED infection is a major complication, usually requiring device removal. The Prevention of Arrhythmia Device Infection Trial (PADIT) was a large cluster crossover trial of standard versus incremental antibiotics. Krahn said the study sought to investigate independent predictors of device infection in PADIT and develop a novel infection risk score. Device procedures were performed in 19,603 patients and hospitalization for infection occurred in 177 (0.90%) within one year. 

Over four six-month periods, 24 centers used either conventional or incremental antibiotic treatment in all patients. The primary outcome was hospitalization for device infection within one year with blinded end-point adjudication. Multivariable logistic prediction modeling was used to identify the independent predictors and develop a risk score for device infection. The model was internally validated with bootstrap methods.

The final prediction model identified five independent predictors of device infection (previous procedures (N), age, decreased renal function, immuno-compromised, and type of procedure) with optimizm-corrected C-statistic of 0.704 (95% CI, 0.660-0.744).

The PADIT infection risk score ranging from 0 to 14 points classified patients into three risk groups:

   • Low (0-4)

   • Intermediate (5-6)

   • High (≥7)

The risk groups had rates of hospitalization for infection of 0.51%, 1.42% and 3.41%, respectively (also see figure 1). Subgroup analysis by PADIT infection risk score of the two antibiotic regimes showed no treatment effect (pinteraction = 0.37).

All the HRS 2019 late-breaking studies 

Link to other HRS 2019 news

Reference: 

1. Krahn AD, Longtin Y, Philippon F, et al. Prevention of Arrhythmia Device Infection Trial: The PADIT Trial. J Am Coll Cardiol. 2018 Dec 18;72(24):3098-3109. doi: 10.1016/j.jacc.2018.09.068.

This is a brief overview of updates on implantable cardioverter defibrillator (ICD) including new technology introductions, advancements to mitigate patient risks and ICD controversies. 

The biggest trends in ICD technology have been a movement to smaller devices, simplified implantation, and reducing or eliminating leads implanted in the veins or the heart. The U.S. Food and Drug Administration (FDA) also has certified numerous ICDs as magnetic resonance imaging (MRI)-safe with MR-conditional labeling, to allow patients with ICDs to undergo MRI scans. New software is helping increase battery life, reduce unnecessary shocks and better monitor heart failure patients to prevent acute hospitalizations. Use of antibacterial envelopes was also recently shown to reduce ICD infection risk.

ICD controversies include heightened FDA concerns about ICD cybersecurity, recent data showing ICD implantation disparities based on race and gender, the safety of ICD patients being scanned at airport security checkpoints, a high percentage of patients who meet ICD guidelines but are not receiving them, and patients who do not qualify for ICDs but are receiving them. These issues and new technologies are all detailed in the sections below. 

Advancements in Subcutaneous ICD Technology

One issue with ICDs is the need to implant transvenous leads, which come with their own set of complications including infection risks, more invasive procedures and potential obstruction of the vessels as the leads become encased in scar tissue. This last point also makes the leads difficult to remove if and when they need to be replaced. This has led to the development of subcutaneous ICDs that instead place the leads under the sternum and leave the venous system untouched. 

The FDA cleared the first subcutaneous ICD a few years ago, Boston Scientific's Emblem S-ICD. Medtronic is now developing a subcutaneous ICD which it called the Extravascular (EV) ICD system. First-in-human pilot study data on 21 patients was presented as a late-breaking trial at the Heart Rhythm Society's 2019 meeting. It showed no major complications and was able to sense, pace and defibrillate the heart. The EV ICD system was designed to provide the same benefits of traditional transvenous ICDs, including lifesaving defibrillation, anti-tachycardia pacing to terminate arrhythmias, post-shock pacing to protect from sudden cardiac arrest and temporary back-up bradycardia pacing. It is the same size (33 cc) and shape as traditional ICDs. The EV ICD device is implanted in the left mid-axillary region below the left armpit, and the lead is placed under the sternum. 

"I am very encouraged by our pilot experience using the Medtronic EV ICD system in patients out to three months,” said Ian Crozier, M.D., Department of Cardiology, Christchurch Hospital, Christchurch, New Zealand, principal investigator (PI) in the pilot study. “This small but important study affirms the potential of this new extravascular approach to provide pacing and lifesaving defibrillation therapy without the risks that accompany transvenous leads implanted inside the heart and veins.”

Medtronic said the data from the pilot trial will be used in developing a pivotal trial for commercialization of the device. 

The Boston Scientific S-ICD continues to show positive data in clinical trials. Most recently at Heart Rhythm 2019, the late-breaking UNTOUCHED study evaluated safety and efficacy of the Emblem S-ICD system for primary prevention of sudden cardiac death in patients with a left ventricular ejection fraction (LVEF) below 35 percent. This is the most common population to be indicated for ICD therapy, and the study confirmed the S-ICD had a complication-free rate of 95.8 percent at 30 days post-procedure and high conversion efficacy (99.2 percent) of induced ventricular fibrillation, rates comparable to those seen in previous S-ICD and transvenous ICD studies.

The UNTOUCHED study also reviewed procedure techniques and 30-day outcomes. The majority (69 percent) of procedures were performed using a two-incision technique. The technique had a mean implant time of 55.8 minutes, which was 8 minutes faster than the mean 63.8 minutes for procedures that leveraged a three-incision implant technique, with comparable complication and conversion success rates.  

"We found that the complication rate within this primary prevention population was as low as in prior S-ICD registries, despite the patients having much lower LVEF, more hypertension and diabetes – underscoring that sicker patients do well with this device for the prevention of sudden death," said Lucas V.A. Boersma, M.D., Ph.D., study principal investigator and electrophysiologist at St. Antonius Hospital, the Netherlands. "These acute outcomes also validate the advantages of the two-incision implant technique, which has continued to gain worldwide adoption in the last few years."

Watch the VIDEO: Overview of Subcutaneous ICD Technology, an interview with Boersma.

Analysis of the LATITUDE database evaluating the successful reduction of inappropriate shocks using the Smart Pass sensing filter with the Emblem S-ICD was presented at Heart Rhythm 2018. The technology filters out certain signals that are the primary reason for inappropriate shocks, while still accurately detecting ventricular tachycardia or ventricular fibrillation and delivering lifesaving therapy. Study authors evaluated the effect of Smart Pass on shocks in ambulatory patients and found that the filter reduced the risk of the first inappropriate shock by 50 percent and the risk for all inappropriate shocks by 68 percent, without a negative impact on delivery of appropriate shocks.

New ICD Technologies

There have been several new device introductions to the U.S. market in the past couple years. The biggest trends in ICDs have been smaller devices, simplified implantation, reducing or eliminating leads implanted in the veins or the heart, and a movement toward MRI-conditional labeling. 

In April 2019, Biotronik launched the Acticor device family of new ICDs and cardiac resynchronization therapy defibrillators (CRT-Ds).

When implanted with Biotronik's Plexa ProMRI S DX lead, the hybrid ICD Acticor systems offer dual-chamber diagnostics without the need for an atrial lead. All three Acticor DX devices feature a new DF4 header configuration with a penta-polar electrode lead cable design that simplifies the implant procedure for physicians. Biotronik's DX technology enables the detection of silent atrial fibrillation and allows for supraventricular tachycardia (SVT) discrimination to prevent unnecessary shocks. By reducing the number of leads, procedure times are faster and costs and complications are decreased, the vendor said.

Acticor is approved for use in full-body, 3.0T magnetic resonance imaging (MRI) scans. The new devices measure 10 mm thin, with a smooth, rounded shape that eases implantation and increases patient comfort. The devices have improved battery longevity of nearly 14 years for Acticor DX, and 11 years for both Rivacor CRT and Acticor CRT-DX. 

Boston Scientific launched the Resonate family of ICD and CRT-D systems in September 2017. The new devices are FDA-cleared with MR-conditional labeling and feature the HeartLogic Heart Failure Diagnostic to help physicians improve heart failure (HF) management. This feature alerts physicians of worsening HF by combining data from sensors evaluating heart sounds, respiration rate and volume, thoracic impedance, heart rate and activity. The alert is the first HF diagnostic in an implantable device that has been validated to have an observed sensitivity of 70 percent as well as the ability to provide weeks of advance notice — a median of 34 days ahead of an impending HF event — and low burden for detecting indications of worsening HF.[1] 

In addition to the HeartLogic Diagnostic, all CRT-Ds in the Resonate family of devices are enabled with SmartCRT Technology to help physicians customize where, when and how to pace the lower chambers of the heart using the Multisite Pacing capability for multi-electrode pacing. The devices also use EnduraLife battery technology, providing physicians with the ability to tailor device settings according to individual patient needs, without adversely draining the battery and causing unnecessary replacement procedures.

Abbott gained FDA clearance in January 2018 for MR-conditional labeling for the Quadra Assura MP CRT-D and Fortify Assura ICD. The approvals follow recent MR-conditional labeling approvals for the Assurity MRI pacemaker, Ellipse ICD and associated MRI-compatible leads, and further expand Abbott's portfolio of MRI-ready devices. In September 2017, Abbott announced FDA clearance for MR-conditional labeling for one of the company's most widely-used ICDs and associated high voltage leads — the Ellipse ICD with the Tendril MRI pacing lead and Durata and Optisure high voltage leads. 

Abbott's Fortify Assura ICD and Quadra Assura MP CRT-D also include the company's suite of TailoredTherapy features, which are designed to provide additional flexibility and control in how therapy is delivered as a patient's therapy needs change over time. The feature set helps protect against the delivery of unnecessary shocks and continuously evaluates the condition of a lead to consistently deliver appropriate therapy. 

Mitigating ICD Infection Risks

Infection risk from creating surgical pockets for implantable devices and the seriousness of infected leads that travel into the venous vasculature and the heart has been a major topic of discussion every year at electrophysiology meetings. Two advances in this area were reported in late-breaking trials at the American College of Cardiology (ACC) and Heart Rhythm 2019 annual meetings.

The WRAP-IT trial demonstrated Medtronic’s Tyrx Absorbable Antibacterial Envelope reduced the risk of major infection by 40 percent, and pocket infection by 61 percent, in patients with cardiac implantable electronic devices (CIEDs). The improvements were in comparison to standard-of-care pre-operative antibiotics.[2]

“CIED infections are associated with significant morbidity, mortality and cost. Until now, in addition to adhering to strict surgical techniques, only one intervention, pre-operative antibiotics, has been shown to significantly reduce infections,“ said Khaldoun Tarakji, M.D., MPH, associate section head of cardiac electrophysiology at Cleveland Clinic, principal investigator of the trial. “This study shows that, in addition to pre-operative antibiotics, the use of the antibacterial envelope significantly reduced the risk of CIED infections, and with no increased risk of complications.”

Watch a VIDEO interview with Tarakji about the WRAP-IT Trial. 

A new infection risk scoring system was developed based on data from the large PADIT Trial.[3] The new scoring system was presented at Heart Rhythm 2019.

"We developed a novel infection risk score in the largest cardiovascular implantable electronic device (CIED) trial to date, with five independent predictors that are readily adopted into clinical practice," explained Andrew D.. Krahn, M.D., FHRS, professor in the Division of Cardiology at the University of British Columbia, who presented the study. He said the PADIT infection score warrants validation in an independent cohort study.

CIED infection is a major complication, usually requiring device removal. The Prevention of Arrhythmia Device Infection Trial (PADIT) was a large cluster crossover trial of standard versus incremental antibiotics. Krahn said the study sought to investigate independent predictors of device infection in PADIT and develop a novel infection risk score. Device procedures were performed in 19,603 patients and hospitalization for infection occurred in 177 (0.9 percent) within one year. Over four six-month periods, 24 centers used either conventional or incremental antibiotic treatment in all patients. The primary outcome was hospitalization for device infection within one year with blinded end-point adjudication. Multivariable logistic prediction modeling was used to identify the independent predictors and develop a risk score for device infection. The model was internally validated with bootstrap methods.

The final prediction model identified five independent predictors of device infection (previous procedures (N), age, decreased renal function, immuno-compromised and type of procedure) with optimize-corrected C-statistic of 0.704 (95 percent CI, 0.660-0.744).

The PADIT infection risk score ranging from 0 to 14 points classified patients into three risk groups:
   • Low (0-4)
   • Intermediate (5-6)
   • High (≥7)

The risk groups had rates of hospitalization for infection of 0.51, 1.42 and 3.41 percent respectively. Subgroup analysis by PADIT infection risk score of the two antibiotic regimes showed no treatment effect.

Race and Gender Disparities in ICD Implants

Three new studies presented at Heart Rhythm 2019 showed patients who are medically indicated for implantable heart devices, including ICDs and CRT, often do not receive needed therapy. The findings underscore gender and race treatment disparities, as well as a lack of referrals to physicians to implant the devices. The analyses were supported by Medtronic and used Optum Electronic Health Records (EHR) datasets and algorithms developed as part of the Medtronic GLIDE HF (GuideLine Indications Detected in EHR for HF) initiative.

“Device usage across both gender and race was strikingly low, despite medical records documenting patient eligibility for the therapy,” said Anne B. Curtis, M.D., study author and SUNY Distinguished Professor of Medicine in the Jacobs School of Medicine and Biomedical Sciences at the University at Buffalo, Buffalo, N.Y. “The breadth of practice type – from academic medical centers to community hospitals – along with the sheer number of patients highlight the seriousness of the challenge.”

A real-world assessment of disparities among people indicated for the therapies, based on medical society guidelines, found devices were implanted more frequently in indicated men than women (16.7 vs. 12.7 percent), but were significantly underused in all patient populations. In the analysis, both women and men of color and white women received devices at lower rates than white men. This analysis of EHR data from more than 1 million patients is consistent with previous research showing that black patients are considerably less likely to receive cardiac interventions.

The real-world analysis using electronic health record (EHR) data looked at the utilization rates of device therapies in heart failure patients as defined by medical society (ACCF/AHA/HRS) guidelines. The analysis showed that ICDs and CRT-Ds are substantially underutilized compared to other cardiovascular interventions such as imaging, drug therapies and coronary procedures. Less than one-third (32.3 percent) of eligible patients received CRT, and 11 percent of eligible patients received ICDs. The analysis showed consistent underutilization trends across five years (2012-16) in more than 100,000 patients.

A separate analysis of EHR data assessed referral and implant patterns among ICD-indicated patients. The analysis revealed that half (50.5 percent) of ICD-indicated patients were referred to an electrophysiologist. Patients referred to and seen by an electrophysiologist were more likely to receive ICDs. About 44.3 percent of patients seen by an electrophysiologist received a device, according to the study. Among patients who did not see an electrophysiologist, only 8.8 percent received a device.

“While each of these analyses evaluated different aspects of implantable cardiac device use, the unifying theme is that far too many patients are not getting all of the therapies that could provide them with significant benefit,” said Rob Kowal, M.D., Ph.D., vice president and chief medical officer of the cardiac rhythm and heart failure division at Medtronic. “Implantable defibrillators and CRT-Ds are life-saving devices, so there is a clear need to address barriers to proper care for indicated patients.”

ICD Cybersecurity Concerns

As implantable devices increasingly go wireless to supply data to automated patient monitoring systems and physician offices, in an era where cyberattacks on healthcare and IT systems are growing, the FDA has raised concerns. The agency said hackers could potentially target patients directly, even inadvertently when hacking into other hospital systems. So, the FDA has been monitoring cybersecurity vulnerabilities associated with the internet connection of EP devices. The FDA is concerned ICDs remotely accessed by hackers could present a life-threatening situation.

Medtronic was the latest device manufacturer to face agency cybersecurity scrutiny. In March 2019, the FDA issued a safety communication to alert healthcare providers and patients about the cybersecurity vulnerabilities identified in a wireless telemetry technology used for communication between Medtronic’s ICDs, cardiac resynchronization therapy defibrillators (CRT-Ds), clinic programmers and home monitors. The FDA said a wireless telemetry protocol used for communication between the devices and their programming and monitoring systems has cybersecurity vulnerabilities because it does not use encryption, authentication or authorization. The FDA said this makes these system easy to hack into. The FDA said although the system’s overall design features help safeguard patients, Medtronic is developing updates to further mitigate these cybersecurity vulnerabilities.

In 2018, the FDA raised concerns over a vulnerability found associated with using an internet connection to update software between the Medtronic CareLink and CareLink Encore programmers and Medtronic's software distribution network (SDN). Software updates normally include new software for the programmer's functionality as well as updates to implanted device firmware. Although the programmer uses a virtual private network (VPN) to establish an internet connection with the Medtronic SDN, the FDA said the vulnerability identified with this connection is that the programmers do not verify that they are still connected to the VPN prior to downloading updates. To address that cybersecurity vulnerability and improve patient safety, the FDA cleared an update in October 2018 to the Medtronic network that will intentionally block the currently existing programmer from accessing the Medtronic SDN.

In 2017, the FDA raised concerns with Abbott (formerly St. Jude Medical) pacemakers and defibrillators because they contained configurable embedded computer systems that can be vulnerable to cybersecurity intrusions and exploits. The FDA approved an Abbott firmware update in August 2017 to reduce the risk of patient harm due to potential exploitation of cybersecurity vulnerabilities.     

ICDs Not Meeting Medicare Coverage Criteria Decline After Overuse Investigation Announced

Placement of ICDs not meeting the Centers for Medicare and Medicaid Services (CMS) National Coverage Determination criteria declined following the announcement of a U.S. Department of Justice (DOJ) investigation into potential overuse of such devices. This was according to data from the National Cardiovascular Data Registry (NCDR) ICD Registry between 2007 and 2015, published in the Journal of the American Medical Association in July 2018.[4]

CMS created a National Coverage Determination (NCD) for ICDs in 2005. It incorporated the available clinical evidence and aligned payment practices for primary prevention ICDs in patients insured under Medicare. The DOJ notified hospitals of an investigation into potential overuse of ICDs in 2010 and the investigation was made public in January 2011. Upon the conclusion of the investigation in February 2016, the DOJ reached settlements with more than 500 hospitals for more than $280 million total for Medicare claims not meeting the NCD.

“When the National Coverage Determination was first announced, there were concerns about potential overuse of ICDs,” said Nihar Desai, M.D., MPH, lead author of the study and assistant professor of medicine at Yale School of Medicine. “Between 2007 and 2015, there were significant declines in the proportion of primary prevention ICDs placed for indications not meeting National Coverage Determination criteria at all hospitals, with larger and more rapid declines after the announcement of the investigation at hospitals that reached settlements with the DOJ. There were similar declines observed among non-Medicare patients.”

Using NCDR ICD Registry data to determine if the DOJ investigation changed clinical practice, researchers analyzed 300,151 primary prevention ICDs in Medicare patients at 1,809 hospitals between January 2007 and December 2015. Of the 502 publicly named hospitals that reached a settlement with DOJ, 470 were matched to facilities in the ICD Registry. Two facilities were confirmed to have closed, and 16 did not submit data or their data did not meet NCDR quality standards. Researchers also analyzed the data of non-Medicare patients to determine if the DOJ investigation impacted the overall patient population undergoing ICD implantation.

In the first half of 2007, 25.8 percent of ICDs at hospitals that settled and 22.8 percent of ICDs at hospitals that did not settle did not meet the National Coverage Determination. Over the full study period, there was a 16.1 percent decline in ICDs not meeting the National Determination Coverage criteria at hospitals that settled with the DOJ and a 12.1 percent decline in hospitals that had not.

The interrupted time series analysis found prior to the announcement of the DOJ investigation that the proportion of ICD placements not meeting the NCD was relatively stable, and the rate of decline was modest and similar among all hospitals. During the DOJ investigation announcement, researchers found significant declines in the proportions of ICDs not meeting the National Coverage Determination at all hospitals. However, the rate was much larger and more rapid at hospitals that went on to reach settlements. At the end of the study, the number of ICDs not meeting the National Coverage Determination criteria was similar in both groups.

Rates of ICD implants not meeting the NCD criteria also fell among non-Medicare patients at both hospitals that did and did not settle with the DOJ.

Overall, there were declines in ICD implants not meeting the NCD, but there was variation at the hospital level. At top performing facilities, less than 3.8 percent of ICD implants did not meet the National Coverage Determination criteria while lower performing facilities had more than 14.3 percent of ICD implants not meeting the criteria.

Airport Security Body Scanners Do Not Interfere With ICDs

Results from new research presented at Heart Rhythm 2019 show that passengers with CIEDs, including pacemakers and ICDs, can safely travel through airport security checkpoint scanners. This is the first study to look at the relationship between body scanners and the impact on functionality of devices. The study showed no negative interference of any device after analyzing more than 1,000 scans. There were no events of electromagnetic interference (EMI) during the body scans across 375 devices. Further, no CIEDs were detected by the body scanners.

Body scanners are increasingly being used worldwide and are replacing conventional metal detectors. These scanners represent a potential new source of electromagnetic interference (EMI). EMI is a disturbance known to cause pacing inhibition or inappropriate shock therapy. Patients are advised to manage this potential risk by limiting their exposure to certain technologies including metal detectors, magnets, MRI scans and other medical procedures.

Prior to conducting the study, the authors surveyed more than 1,000 patients and found that 80 percent have fears or concerns about passing through body scanners at the airport. The survey information further reinforces the need to clarify the safety of airport security body scans for passengers with CIEDs.

The study included 375 patients enrolled between May 2017 and October 2018. The devices studied included ICD (n=175, 47 percent), conventional pacemakers (PM) (n=127, 33 percent), subcutaneous ICD (S-ICD) (n=52, 14 percent) and leadless pacemakers (LCP) (n=21, 6 percent). The sensitivity levels of the devices were not altered, ICD shock therapy was disabled and permanent ventricular pacing was ensured to facilitate the detection of EMI. The primary endpoint was EMI events including pacing inhibition, upper rate tracking, tachycardia detection and spontaneous reprogramming. The secondary endpoint was the incidence of CIED detection by the body scanner.

"We were surprised to learn that so many patients expressed concerns about the functionality of their devices while traveling. We wanted to help put their minds at ease by testing the potential interference body scanners could have on common devices like pacemakers and defibrillators," said lead author Carsten Lennerz, M.D., MSci, German Heart Centre Munich. "Our study results show that now patients can travel worry-free knowing they can safely go through security checkpoints without the need of disclosing personal medical information."

Related ICD Content:

Advances in Implantable Cardioverter Defibrillator (ICD) Technology

What is New in Electrophysiology Technologies

VIDEO: Overview of Subcutaneous ICD Technology — Interview with Lucas Boersma, M.D.

VIDEO: Advances in Electrophysiology Technology— Interview with Michael Gold, M.D.

References: 

1. Boehmer, J,  Hariharan R, Devecchi FG, et al., “A Multisensor Algorithm Predicts Heart Failure Events in Patients With Implanted Devices: Results From the MultiSENSE Study.” JACC-HF, JACC Heart Fail. 2017 Mar;5(3):216-225. doi: 10.1016/j.jchf.2016.12.011.

2. Tarkji K.G., Mittal S., Kennergren C., et al. Antibacterial Envelope to Prevent Cardiac Implantable Device Infection. New England Journal of Medicine, March 17, 2019. DOI: 10.1056/NEJMoa1901111.

3. Krahn AD, Longtin Y, Philippon F, et al. Prevention of Arrhythmia Device Infection Trial: The PADIT Trial. J Am Coll Cardiol. 2018 Dec 18;72(24):3098-3109. doi: 10.1016/j.jacc.2018.09.068.

4. Desai N.R., Bourdillon P.M., Parzynski C.S., et al. "Association of the U.S. Department of Justice Investigation of Implantable Cardioverter-Defibrillators and Devices Not Meeting the Medicare National Coverage Determination, 2007-2015," Journal of the American Medical Association, July 3, 2018. doi:10.1001/jama.2018.8151.

For patients at risk for sudden cardiac arrest (SCA) who are being evaluated for a permanent implantable cardioverter defibrillator (ICD), Zoll offers the LifeVest wearable external defibrillator as a temporary solution. It allows a physician more time to assess a patient’s long-term arrhythmic risk and make appropriate plans.

The LifeVest is lightweight and easy to wear under a patient’s clothing, allowing them to return to their daily activities while having the peace of mind that they are protected from SCA. The LifeVest continuously monitors the patient’s heart and, if a life-threatening heart rhythm is detected, the device delivers a treatment shock to restore normal heart rhythm. This device continuously monitors the patient’s heart with dry, non-adhesive sensing electrodes to detect life-threatening abnormal heart rhythms. If a life-threatening heart rhythm is detected, the device alerts bystanders and delivers a treatment shock to restore normal heart rhythm. The entire event, from detecting a life-threatening arrhythmia to automatically delivering a treatment shock, usually occurs in less than a minute.

The LifeVest is used for a range of patient conditions or situations, including following a heart attack and before or after bypass surgery or stent placement, as well as for those with cardiomyopathy or congestive heart failure that places them at particular risk.

Zoll intregrates this device with the LifeVest Network online patient data management system. It allows clinicians to monitor the patient using downloaded data from a patient’s LifeVest. Clinicians can customize events that generate an alert, or to be notified for a number of events, such as detected arrhythmias, treatments, patient-recorded electrocardiograms (ECGs) and patient use.

Other LifeVest Related Content:

VIDEO: Demonstration of the LifeVest Wearable Defibrillator System

Diving Deeper Into the Results of the VEST Trial Using Wearable Defibrillators

Wearable Cardioverter Defibrillators Prove Safe for Pediatric Patients

New Technology and Market Challenges Facing Implantable Cardioverter Defibrillators

July 31, 2019 — The chances of patients experiencing complications after having a cardiac device implanted vary according to where they have the procedure.

A study of 174 hospitals in Australia and New Zealand published in the Annals of Internal Medicine shows that the quality of care people receive may account for the wide variation in the rate of complications after having a cardiovascular implantable electronic device (CIED) insertion.

“The study included 81,304 patients who received a new CIED with 65,711 permanent pacemakers and 15,593 implantable cardioverter-defibrillators,” said the study’s lead author, University of Adelaide’s Isuru Ranasinghe, Ph.D., senior cardiologist, Central Adelaide Local Health Network. “Permanent pacemakers and implantable cardioverter-defibrillators are among the most common and costly devices implanted in hospitals.

“CIED complications are common with 8.2 percent of patients implanted with new devices having a major device-related complication within 90 days of their operation. Complications experienced by patients vary between two- and three-fold among hospitals, which suggests that there is significant variation in CIED care quality,” added Ranasinghe

Nearly 19,000 pacemakers and more than 4000 defibrillators were implanted in Australia alone last year. Pacemakers are often fitted to elderly people who suffer from bradycardia where their heart beats too slowly. They use electrical pulses to prompt the heart to beat at a normal rate. Cardioverter-defibrillators track a person’s heart rate, and if an abnormal heart rhythm is detected, the device delivers an electric shock to restore the heart rhythm to normal.

“Serious complications can cause considerable patient harm and adds to avoidable healthcare costs. About 60 percent of these complications occur after leaving the hospital so many doctors and hospitals may not be fully aware of the complications experienced by patients,” said Ranasinghe.

Associate Prof. Anand Ganesan, a study co-investigator and a cardiac electrophysiologist at Flinders Medical Centre said, “What this study really shows is that we should be routinely reporting hospital complication rates to make these fully visible to clinicians, hospitals and the community at large. We should also invest in strategies proven to reduce these, such as optimizing procedural technique, adopting better infection control measures and managing blood thinning drugs peri-procedure.”

Ranasinghe said, “Encouraging hospitals to take part in quality improvement activities such as auditing complications and engaging in clinical quality registries also reduce complications over time.”

This study was funded by the HCF Research Foundation, with additional funding support from the National Heart Foundation of Australia and The Hospital Research Foundation.

For more information: www.annals.org

Reference

1. Ranasinghe I., Labrosciano C., Horton D., et al. Institutional Variation in Quality of Cardiovascular Implantable Electronic Device Implantation: A Cohort Study. Annals of Internal Medicine, published online July 30, 2019. DOI: 10.7326/M18-2810