The Entirely Subcutaneous Implantable Cardioverter-Defibrillator

• Published in: Journal of the American College of Cardiology 2012-11, Vol.60 (19), p.1933-1939
• Main Authors: Olde Nordkamp, Louise R.A., MD, Dabiri Abkenari, Lara, MD, Boersma, Lucas V.A., MD, PhD, Maass, Alexander H., MD, PhD, de Groot, Joris R., MD, PhD, van Oostrom, Antonie J.H.H.M., MD, PhD, Theuns, Dominic A.M.J., PhD, Jordaens, Luc J.L.M., MD, PhD, Wilde, Arthur A.M., MD, PhD, Knops, Reinoud E., MD
• Format: Article
• Language: English
• Subjects: Cardiac arrhythmia; Cardiology; Cardiovascular; Defibrillators; Heart; Heart attacks; heart rhythm disturbances; ICD; implantable cardioverter-defibrillator; Infections; Internal Medicine; Mortality; Pain; Software upgrading; subcutaneous; Transcutaneous electrical nerve stimulation-TENS; Values; ventricular arrhythmia
• ISSN: 0735-1097; 1558-3597
• DOI: 10.1016/j.jacc.2012.06.053

Objectives The purpose of the study was to evaluate the efficacy and safety of the entirely subcutaneous implantable cardioverter-defibrillator (S-ICD). Background A new entirely S-ICD has been introduced, that does not require lead placement in or on the heart. The authors report the largest multicenter experience to date with the S-ICD with a minimum of 1-year follow-up in the first 118 Dutch patients who were implanted with this device. Methods Patients were selected if they had a class I or IIa indication for primary or secondary prevention of sudden cardiac death. All consecutive patients from 4 high-volume centers in the Netherlands with an S-ICD implanted between December 2008 and April 2011 were included. Results A total of 118 patients (75% males, mean age 50 years) received the S-ICD. After 18 months of follow-up, 8 patients experienced 45 successful appropriate shocks (98% first shock conversion efficacy). No sudden deaths occurred. Fifteen patients (13%) received inappropriate shocks, mainly due to T-wave oversensing, which was mostly solved by a software upgrade and changing the sensing vector of the S-ICD. Sixteen patients (14%) experienced complications. Adverse events were more frequent in the first 15 implantations per center compared with subsequent implantations (inappropriate shocks 19% vs. 6.7%, p = 0.03; complications 17% vs. 10%, p = 0.10). Conclusions This study demonstrates that the S-ICD is effective in terminating ventricular arrhythmias. There is, however, a considerable percentage of ICD related adverse events, which decreases as the therapy evolves and experience increases.