[Subcutaneous defibrillator (S-ICD)].

Abstract

Defibrillator treatment should adhere to the guidelines to effectively prevent sudden cardiac death while minimizing all complications. As an entirely extrathoracic system, the subcutaneous implantable cardioverter defibrillator (S-ICD) eliminates the need for intracardiac leads, thus reducing procedural and lead-related complications as well as systemic infections. The evidence across > 5000 participants in randomized trials and registries demonstrates approximately 98% shock conversion with low complication rates. The PRAETORIAN study demonstrated that the S‑ICD is not inferior to the transvenous ICD (TV-ICD), long-term and secondary analyses indicate fewer severe, particularly lead-related, complications with S‑ICD treatment. Studies such as UNTOUCHED, EFFORTLESS, and PAS confirm its shock effectiveness and safety profile in routine clinical care, while the ATLAS study reports significantly fewer perioperative lead-related complications in younger patients. The procedure has been streamlined and standardized, incorporating best practices such as preoperative vector screening, a two-incision technique, intermuscular/submuscular pocket creation, and dual-zone programming with morphology/high-pass filtering. In the absence of indications for bradypacing, cardiac resynchronization therapy (CRT) or antitachycardia pacing (ATP), the S‑ICD should be considered a routine option in the clinical routine, especially for younger patients, those prone to infections, those with limited venous access and individuals with hereditary arrhythmia syndromes.