Potentially lifesaving implantable cardioverter defibrillators underutilized in eligible patients

Only 57% of qualified patients receive the potentially lifesaving implant, according to the Canadian Journal of Cardiology

Philadelphia, PA, September 7, 2017

Fewer than 10% of people who experience sudden cardiac arrest (SCA) outside of a hospital survive. Reoccurrence rates after an initial event are high, which is why current Canadian Cardiovascular Society, as well as other international guidelines, strongly recommend the use of implantable cardioverter defibrillators (ICDs) in selected patients who survive cardiac arrest. Despite this recommendation, a new study published in the Canadian Journal of Cardiology reveals that real-life ICD utilization rates are lower than expected.

Investigators analyzed medical records from over 1200 patients in the greater Toronto area who had survived an out of hospital cardiac arrest. Subjects were deemed “likely ICD eligible” if they would have benefited from ICD implantation as defined by three parameters: having a shockable initial rhythm, no definite ischemia, and a good neurologic status. Out of patients who were assessed as “likely ICD eligible,” only 57% received an ICD. Meanwhile, the implantation rate for “not likely ICD eligible” patients was 16.7%, while the overall implementation rate was 23.9%.

“This study illustrates that examining how medical care actually delivered in the ‘real world’ conforms to guidelines is vital in order to evaluate and improve care,” explained lead investigator Paul Dorian, MD, MSc, Department Director, Division of Cardiology, University of Toronto and Staff Cardiac Electrophysiologist at St. Michael’s Hospital. “Our findings are the first step in the process to improve the quality of care provided to these patients, by assessing if the right patients receive the right treatment. The next step should be to understand ‘why’, and to promote guideline-appropriate care.”

While investigators acknowledged that it was unrealistic to expect the ICD implantation rate to be 100%, they had expected it to be higher than 57% in the eligible population. Researchers determined that the highest rate of death one year post-cardiac arrest was among individuals who were ICD eligible, but who did not receive an ICD. Among patients who received an ICD, there were fewer deaths compared to those who did not.

ICD implantation capability of the admission hospital was found to be a significant predictor of whether or not a patient received an ICD. “There is insufficient information in this database to determine why this association exists, but some possible explanations include the absence of a local electrophysiology consultation service, perceived difficulty in access or transfer to implantation facilities, or differences in the specialty of the most responsible physician at the admission hospitals,” noted Dr. Dorian. This treatment gap suggests that improved education and sensitization might be needed to avoid patients not receiving this potentially life-saving therapy simply because they have been managed in a hospital without specialized local expertise in the area.

Sudden cardiac death (SCD) as a result of cardiac arrest is projected to be the number one cause of death worldwide by 2020. SCD is currently responsible for more life-years lost than all other leading causes of death, including individual cancers. ICDs can detect and stop the ventricular arrhythmias responsible for SCD, lowering the risk of death by more than 30%.

In an accompanying editorial, Ratika Parkash, MD, MS, and Anthony S. L. Tang, MD, offer some perspective on the impact of the results going forward: “This study highlights the importance of implementation of guidelines with knowledge translation programs that may assist in identifying truly eligible patients for both primary and secondary prevention ICDs, and thus providing this life-saving therapy where significant impact would occur on the rate of SCD in Canada.”


Notes for Editors
The articles are “Implantable Cardioverter Defibrillator Implantation Rates After Out of Hospital Cardiac Arrest: Are the Rates Guideline Concordant?” by Edwin C. Ho, MD; Sheldon Cheskes, MD; Paul Angaran, MD; Laurie J. Morrison, MD, MSc; Theresa Aves, HBSc; Cathy Zhan, MSc; Dennis T. Ko, MD, MSc; Paul Dorian, MD, MSc, on behalf of the Rescu Epistry Investigators (http://dx.doi.org/10.1016/j.cjca.2017.05.013) and “Editorial: Implantable Cardioverter Defibrillators in Sudden Cardiac Death Survivors: Are We Doing All We Can?” by Ratika Parkash, MD, MS, and Anthony S. L. Tang, MD (http://dx.doi.org/10.1016/j.cjca.2017.07.016). They will appear in the Canadian Journal of Cardiology, volume 33, issue 10 (October 2017) published by Elsevier.

Full text of these articles is available to credentialed journalists upon request. Contact Eileen Leahy at +1 732-238-3628or cjcmedia@elsevier.com to obtain copies. Journalists wishing to schedule interviews with the study authors should contact Leslie Shepherd, Communications and Public Affairs, St. Michael’s Hospital, at +1 416-864-6094, ShepherdL@smh.ca; or Liz Pimentel at +1 416 864 5104, pimentell@smh.ca. To reach the authors of the editorial for comment, please contact Ratika Parkash at Ratika.Parkash@nshealth.ca.

The study was supported by grants from the CIHR and the Heart and Stroke Foundation of Canada to the RESCU Epistry registry of cardiac arrest.

About the Canadian Journal of Cardiology
The Canadian Journal of Cardiology is the official journal of the Canadian Cardiovascular Society. It is a vehicle for the international dissemination of new knowledge in cardiology and cardiovascular science, particularly serving as a major venue for the results of Canadian cardiovascular research and Society guidelines. The journal publishes original reports of clinical and basic research relevant to cardiovascular medicine as well as editorials, review articles, case reports, and papers on health outcomes, policy research, ethics, medical history, and political issues affecting practice. www.onlinecjc.ca

About the Editor-in-Chief
Editor-in-Chief Stanley Nattel, MD, is Paul-David Chair in Cardiovascular Electrophysiology and Professor of Medicine at the University of Montreal and Director of the Electrophysiology Research Program at the Montreal Heart Institute Research Center.

About the Canadian Cardiovascular Society
The Canadian Cardiovascular Society is the professional association for Canadian cardiovascular physicians and scientists working to promote cardiovascular health and care through knowledge translation, professional development, and leadership in health policy. The CCS provides programs and services to its 1900+ members and others in the cardiovascular community, including guidelines for cardiovascular care, the annual Canadian Cardiovascular Congress, and, with the Canadian Cardiovascular Academy, programs for trainees. More information about the CCS and its activities can be found at www.ccs.ca.

About Elsevier
Elsevier is a global information analytics business that helps scientists and clinicians to find new answers, reshape human knowledge, and tackle the most urgent human crises. For 140 years, we have partnered with the research world to curate and verify scientific knowledge. Today, we’re committed to bringing that rigor to a new generation of platforms. Elsevier provides digital solutions and tools in the areas of strategic research management, R&D performance, clinical decision support, and professional education; including ScienceDirect, Scopus, SciVal, ClinicalKey and Sherpath. Elsevier publishes over 2,500 digitized journals, including The Lancet and Cell, 39,000 e-book titles and many iconic reference works, including Gray's Anatomy. Elsevier is part of RELX, a global provider of information-based analytics and decision tools for professional and business customers. www.elsevier.com

Eileen Leahy
+1 732-238-3628