News | Implantable Cardioverter Defibrillator (ICD) | July 02, 2018

New Tool Predicts Benefits and Risks of Implantable Defibrillator for Heart Failure Patients

Online model lets cardiologists input patient-specific data to assess potential risk and benefits of deploying implantable cardioverter defibrillator in a patient

New Tool Predicts Benefits and Risks of Implantable Defibrillator for Heart Failure Patients

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:


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:

Related Content

FDA Issues Final Guidance on Live Case Presentations During IDE Clinical Trials
News | Cardiovascular Clinical Studies | July 10, 2019
The U.S. Food and Drug Administration (FDA) issued the final guidance “Live Case Presentations During Investigational...
Veradigm Partners With American College of Cardiology on Next-generation Research Registries
News | Cardiovascular Clinical Studies | July 03, 2019
The American College of Cardiology (ACC) has partnered with Veradigm, an Allscripts business unit, to power the next...
New FDA Proposed Rule Alters Informed Consent for Clinical Studies
News | Cardiovascular Clinical Studies | November 19, 2018
The U.S. Food and Drug Administration (FDA) is proposing to add an exception to informed consent requirements for...
A key slide from Elnabawi's presentation, showing cardiac CT plaque evaluations, showing the impact of psoriasis medication on coronary plaques at baseline and one year of treatment. It shows a reversal of vulnerable plaque development. #SCAI, #SCAI2018

A key slide from Elnabawi's presentation, showing cardiac CT plaque evaluations, showing the impact of psoriasis medication on coronary plaques at baseline and one year of treatment. It shows a reversal of vulnerable plaque development.  

Feature | Cardiovascular Clinical Studies | May 14, 2018
May 14, 2018 – New clinical evidance shows common therapy options for psoriasis (PSO), a chronic inflammatory skin di
Intravenous Drug Use is Causing Rise in Heart Valve Infections, Healthcare Costs. #SCAI, #SCAI2018
News | Cardiovascular Clinical Studies | May 14, 2018
May 14, 2018 — The opioid drug epidemic is impacting cardiology, with a new study finding the number of patients hosp
Patient Enrollment Completed in U.S. IDE Study of THERMOCOOL SMARTTOUCH SF Catheter
News | Cardiovascular Clinical Studies | March 15, 2018
March 15, 2018 –  Johnson & Johnson Medical Devices Companies announced today that Biosense Webster, Inc., who wo
Lexington Begins HeartSentry Clinical Trial
News | Cardiovascular Clinical Studies | February 20, 2018
February 20, 2018 – Lexington Biosciences, Inc., a development-stage medical device company, announced the commenceme
Endologix Completes Patient Enrollment in the ELEVATE IDE Clinical Study
News | Cardiovascular Clinical Studies | February 06, 2018
February 6, 2018 – Endologix, a developer and marketer of treatments for aortic disorders, announced the completion o
12-Month Results from Veryan Medical's MIMICS-2 IDE Study Presented at LINC
News | Cardiovascular Clinical Studies | February 01, 2018
February 1, 2018 – Thomas Zeller (Bad Krozingen, Germany) presented the 12-month results from Veryan Medical’s MIMICS
LimFlow Completes U.S. Feasibility Study Enrollment, Receives FDA Device Status
News | Cardiovascular Clinical Studies | February 01, 2018
February 1, 2018 –  LimFlow SA, developer of minimally-inv
Overlay Init