Long‐term outcomes of subcutaneous implantable cardioverter‐defibrillators: a single‐centre Australian experience

Abstract Background The subcutaneous implantable cardioverter‐defibrillator (S‐ICD) has become an established alternative to overcome conventional transvenous ICD (TV‐ICD) lead‐related complications. Aims To describe the long‐term outcomes of S‐ICD implantation at a single Australian institution. Methods We retrospectively reviewed the clinical outcomes of consecutive patients who underwent S‐ICD implantation from 2015 to 2019. Results In total, 128 patients (median age 52.5 years, 70% male) underwent S‐ICD implantation. The indication was primary prevention in 86 patients (66%), and 22 patients (17%) had a previous transvenous device. Seventy‐seven patients (60%) had heart failure, and the median left ventricular ejection fraction was 36% (29%–60%). The procedure was performed under general anaesthesia in 124 patients (97%), and the median procedure time was 105 min (interquartile range (IQR) 90–120). During a median follow‐up of 4.7 years (IQR 3.8–5.8), 15 patients (12%) died, none of which were due to sudden death or device‐related complications. Inappropriate shocks occurred in 17 patients (13.3%), predominantly due to T‐wave oversensing (4.7%) and supraventricular arrhythmias (4.7%), and 15 patients (11.7%) received appropriate shocks. During the follow‐up period, the S‐ICD system was revised to TV‐ICD in 10 patients (8%), and 24 patients (19%) required S‐ICD generator change. Four patients (3%) underwent surgical intervention due to lead (two) or pocket‐related (two) complications, and two patients (1.5%) developed pocket infection without systemic sepsis. Conclusion In this single‐centre study, S‐ICDs were implanted safely with acceptable device performance and clinical outcomes over long‐term follow‐up.