Subcutaneous implantable cardioverter-defibrillators: long-term results of the EFFORTLESS study. (28th January 2022)

• Record Type: Journal Article
• Authors: Lambiase, Pier D; Theuns, Dominic A; Murgatroyd, Francis; Barr, Craig; Eckardt, Lars; Neuzil, Petr; Scholten, Marcoen; Hood, Margaret; Kuschyk, Jȕrgen; Brisben, Amy J; Carter, Nathan; Stivland, Timothy M; Knops, Reinoud; Boersma, Lucas V A
• Is Part Of: European heart journal. Volume 43:Number 21(2022)
• Page Start: 2037
• Page End: 2050
• Publication Date: 2022-01-28
• Subjects: Implantable cardioverter-defibrillator -- Subcutaneous ICD -- Sudden death -- Primary prevention -- Secondary prevention; Cardiology -- Periodicals; Heart -- Diseases -- Periodicals; 616.12005
• DOI: 10.1093/eurheartj/ehab921
• Languages: English
• ISSNs: 0195-668X

Abstract

Abstract: Aims: To report 5-year outcomes of EFFORTLESS registry patients with early generation subcutaneous implantable cardioverter-defibrillator (S-ICD) devices. Methods and results: Kaplan–Meier, trend and multivariable analyses were performed for mortality and late (years 2–5) complications, appropriate shock (AS) and inappropriate shock (IAS) rates. Nine hundred and eighty-four of 994 enrolled patients with diverse diagnoses (28% female, 48 ± 17 years, body mass index 27 ± 6 kg/m 2, ejection fraction 43 ± 18%) underwent S-ICD implantation. Median follow-up was 5.1 years (interquartile range 4.7–5.5 years). All-cause mortality was 9.3% (95% confidence interval 7.2–11.3%) at 5 years; 703 patients remained in follow-up on study completion, 171 withdrew including 87 (8.8%) with device explanted, and 65 (6.6%) lost to follow-up. Of the explants, only 20 (2.0%) patients needed a transvenous device for pacing indications. First and final shock efficacy for discrete ventricular arrhythmias was consistent at 90% and 98%, respectively, with storm episode final shock efficacy at 95.2%. Time to therapy remained unaltered. Overall 1- and 5-year complication rates were 8.9% and 15.2%, respectively. Early complications did not predict later complications. There were no structural lead failures. Inappropriate shock rates at 1 and 5 years were 8.7% and 16.9%, respectively. Self-terminating inappropriately sensed episodes predicted late IAS. Predictors of late AS included self-terminating appropriately sensed episodes and earlier AS. Conclusion: In this diverse S-ICD registry population, spontaneous shock efficacy was consistently high over 5 years. Very few patients underwent S-ICD replacement with a transvenous device for pacing indications. Treated and self-terminating arrhythmic episodes predict future shock events, which should encourage more personalized device optimization. Structured Graphical Abstract: Structured Graphical Abstract Shock efficacy of appropriate episodes experienced by patients in the EFFORTLESS study. Top left: Torso model of the implant location of the Subcutaneous Implantable Defibrillator (S-ICD) Image provided courtesy of Boston Scientific. © 2022 Boston Scientific Corporation or its affiliates. All rights reserved. Top right: Example S-ICD electrogram recording of a shock (lightning bolt icon) delivered to convert a ventricular arrhythmia. (A) Discrete episodes. (B) Storm episodes.