Subcutaneous implantable cardioverter defibrillator: Can it overtake its transvenous counterpart

Abstract

Over the past decade, the emergence of the subcutaneous implantable cardioverter defibrillator (S‐ICD) has provided cardiologists with an option to provide both primary or secondary prevention treatment of sudden cardiac death (SCD) without the associated risks that come with the use of intracardiac leads. S‐ICD may prove to be a useful option in those who are young, have thromboembolic risk, immunodeficiency states, unfavorable anatomy due to adult congenital heart disease (ACHD). This article reviews the existing literature to determine whether S‐ICD can prove to be a safe alternative in comparison to Transvenous implantable cardioverter defibrillator (TV‐ICD) and in which patient population should S‐ICD be considered over TV‐ICD.

The Field of Cardiac Electrophysiology

“…These S-ICD devices are implanted within the subcutaneous tissue typically on the left side allowing for shock delivery of 80 Joules through tissue adjacent to the heart as opposed to leads directly projecting into the heart chambers (Figures 4 and 5) [31,32]. This difference in function results in a different profile of complications; S-ICD complications include pocket infections and device erosion [33]. Conversely, complications of transvenous ICDs are predominantly due to its lead system and include perforation of cardiac tissue, tamponade, pneumothorax, and lead repositioning [34].…”

“…Conversely, complications of transvenous ICDs are predominantly due to its lead system and include perforation of cardiac tissue, tamponade, pneumothorax, and lead repositioning [34]. Of note, S-ICD devices may be used for many of the same indications of TV-ICDs, such as primary or secondary life-threatening arrythmia prevention or certain patients with congenital or inherited cardiac conditions (including hypertrophic cardiomyopathy, Brugada syndrome, and ischemic and non-ischemic cardiomyopathies, among others) [33]. Therefore, the advent of S-ICDs expands options for patients considering ICD implantation and allows patients and clinicians to work together in determining which risks may be best tolerated in the long term.…”