Subcutaneous ICD Viable Alternative to Conventional System

A multi-center Dutch study presented at Heart Rhythm 2011 shows effectiveness of subcutaneous implantable cardioverter defibrillator system in largest clinical observation to date

SAN FRANCISCO — A new subcutaneous implantable cardioverter defibrillator (S-ICD) system accurately detected and successfully converted all episodes of ventricular fibrillation (VF) in all observed patients. According to a study presented today at Heart Rhythm 2011, the Heart Rhythm Society’s 32nd Annual Scientific Sessions, the S-ICD system was 100 percent effective in converting induced VF through appropriate shock. Sudden death did not occur in any patients. The study findings indicate that the S-ICD system is comparable to the conventional ICD system and is a viable option for selected patients.

The S-ICD system was implanted in 98 patients across three hospitals in the Netherlands, representing the largest S-ICD patient cohort to date. The S-ICDs were implanted according to international guidelines i and efficacy of the S-ICDs was tested after implantation using 65 J shocks. The first 17 patients observed in this study also participated in a study presented at Heart Rhythm 2010 by Gust Bardy, MD, titled, “An entirely subcutaneous only implantable cardioverter defibrillator.” ii

During an average nine month follow-up period, there were no hospitalizations due to heart failure and no patients experienced sudden cardiac death. The S-ICD system accurately detected and successfully converted all episodes of induced VF. A primary prevention indication was present in 62 patients (63 percent) and 41 percent had ischemic cardiomyopathy. Inappropriate therapy occurred in eight patients due to over-sensing, however, recurrences were prevented with reprogramming and inappropriate therapy has not reoccurred to date.

Unlike the conventional ICD system, the S-ICD system is minimally invasive. It does not require direct vascular access to the heart, leading to fewer complications for patients, and is safely explanted if necessary. However, because the S-ICD system shocks the heart externally, it cannot be used by patients who also need pacing.

“This subcutaneous ICD system has proved to be a great option for many of our patients who do not require pacing,” said Lara Dabiri Abkenari, MD, of ErasmusMC in Rotterdam, Netherlands. “Patients with the system have been very satisfied because it is easily implanted, easily removed if needed, and allows patients more arm movement and mobility than the conventional ICD. This S-ICD system is ideal for young adults and all those who are at risk of sudden cardiac arrest yet have no resynchronization or pacing indications.”

The S-ICD system has been accepted in Europe and is being used by physicians as an effective alternative to the conventional ICD system for selected patients. It is currently under review by the U.S. Food and Drug Administration for use in the United States.

Sessions details:
“The Subcutaneous Defibrillator: the Dutch Experience” [May 4, 2011, 1:00 p.m. – 2:30 p.m., Room 2018 Moscone West.]

i Zipes DP, Camm AJ et al (2006) ACC/AHA/ESC 2006 Guidelines for Management of Patients with Ventricular Arrythmias and the Prevention of Sudden Cardiac Death. Eurospace 8:746-837.

ii Bardy GH, Smith WM, Hood MA, Crozier IG, Melton IC, Jordaens L et al (2010) An entirely subcutaneous only implantable cardioverter defibrillator. Ned Engl J Med 363:36 – 44

About Heart Rhythm 2011
Heart Rhythm 2011 takes place May 4-7, 2011 at the Moscone Center in San Francisco, CA. The Society’s Annual Scientific Sessions is the most comprehensive educational event on heart rhythm disorders, offering more than 250 educational opportunities in multiple formats. The world’s most renowned scientists and physicians will present a wide range of heart rhythm topics including cardiac resynchronization therapy, catheter ablation, cardiac pacing and heart failure as well as the latest technology, including state-of-the-art pacemakers and defibrillators.

About the Heart Rhythm Society
The Heart Rhythm Society is the international leader in science, education and advocacy for cardiac arrhythmia professionals and patients, and the primary information resource on heart rhythm disorders. Its mission is to improve the care of patients by promoting research, education and optimal health care policies and standards. Incorporated in 1979 and based in Washington, DC, it has a membership of more than 5,300 heart rhythm professionals in more than 70 countries around the world.

Contact: Kennesha Baldwin
Heart Rhythm Society
(202) 464-3476
[email protected]

Cindy Rahman: (703) 283-8499
Heart Rhythm 2011 Press Room: (415) 978-3514 (this phone number active through Saturday, May 7, 1:00 p.m. PT)