Subcutaneous Implantable Cardioverter Defibrillator Extractions: A Single-Healthcare System Analysis of Incidence and Indications

Introduction: The subcutaneous implantable cardioverter defibrillator (SICD) serves as an alternative to traditional transvenous implantable cardioverter defibrillators in patients who meet criteria for ICD implantation without concurrent need for cardiac pacing. Data on SICD extraction is limited. This study examines the rates of SICD extraction. Methods: A retrospective study of all patients who underwent SICD implantation between 2010 and 2022 at a single healthcare system was performed. The primary endpoint was rate of SICD extraction. Results: A total of 402 patients (67.4% male; 48.5 ± 14.4 years old) underwent SICD implantation. Of these, 158 (39.3%) were for primary prevention in patients with heart failure with reduced ejection fraction, 125 (31.1%) for secondary prevention of ventricular tachyarrhythmias, and 69 (17.2%) for primary prevention in patients with hypertrophic cardiomyopathy with high-risk features. 29 (7.2%) patients (86.2% male; 51.5 ±12.9 years old) underwent SICD extraction during a mean follow up of 4.5 years. The median length of time between implant and explant was 49.1 [26.7-64.9] months. The most common indications for SICD extraction were need for pacing (17.2%), infection (17.2%), inappropriate shocks due to oversensing (13.8%), and lead failure (10.3%). There were no significant differences in average age, sex, or comorbidity profile between those who did and did not necessitate SICD extraction (extraction: 51.5 ± 12.9 years; no extraction: 48.4 ± 14.5 years; p=0.26) (Table). Conclusions: In appropriately selected patients undergoing implantation of the SICD, the likelihood of needing the device extracted was low at only 7.2% over 4.5 years, with the most common indications for extraction being need for pacing and infection. Further work must be done to determine whether these results regarding rates of, and indications for, SICD extractions are transferrable to other health systems.