Sex differences among subcutaneous implantable cardioverter-defibrillator recipients: a propensity-matched, multicentre, international analysis from the i-SUSI project
Authors: Schiavone Marco , Gasperetti Alessio , Vogler Julia , Compagnucci Paolo , Laredo Mikael , Breitenstein Alexander , Gulletta Simone , Martinek Martin , Kaiser Lukas , Tundo Fabrizio , Palmisano Pietro , Rovaris Giovanni , Curnis Antonio , Kuschyk Jürgen , Biffi Mauro , Tilz Roland , Di Biase Luigi , Tondo Claudio , Forleo Giovanni B ,   i-SUSI investigators, Gasperetti A , Arosio R , Viecca M , Forleo G B , Schiavone M , Tundo F , Moltrasio M , Tondo C , Ziacchi M , Diemberger I , Angeletti A , Biffi M , Fierro N , Gulletta S , Bella P Della , Mitacchione G , Curnis A , Compagnucci P , Casella M , Russo A Dello , Santini L , Pignalberi C , Magnocavallo M , Piro A , Lavalle C , Picarelli F , Ricciardi D , Bressi E , Calò L , Montemerlo E , Rovaris G , De Bonis S , Bisignani A , Bisignani G , Russo G , Pisanò E , Palmisano P , Guarracini F , Vitali F , Bertini M , Vogler J , Fink T , Tilz R , Fastenrath F , Kuschyk J , Kaiser L , Hakmi S , Laredo M , Waintraub X , Gandjbakhch E , Badenco N , Breitenstein A , Saguner A M , Martine M , Seidl S , Zhang X , Di Biase L 
Published: May 2024

Abstract

Aims
Women have been historically underrepresented in implantable cardioverter-defibrillator (ICD) trials. No data on sex differences regarding subcutaneous ICDs (S-ICD) carriers have been described. Aim of our study was to investigate sex-related differences among unselected S-ICD recipients.

Methods and results
Consecutive patients enrolled in the multicentre, international i-SUSI registry were analysed. Comparisons between sexes were performed using a 1:1 propensity matching adjusted analysis for age, body mass index (BMI), left ventricular function, and substrate. The primary outcome was the rate of appropriate shocks during follow-up. Inappropriate shocks and other device-related complications were deemed secondary outcomes. A total of 1698 patients were extracted from the i-SUSI registry; 399 (23.5%) were females. After propensity matching, two cohorts of 374 patients presenting similar baseline characteristics were analysed. Despite similar periprocedural characteristics and a matched BMI, women resulted at lower risk of conversion failure as per PRAETORIAN score (73.4% vs. 81.3%, P = 0.049). Over a median follow-up time of 26.5 [12.7–42.5] months, appropriate shocks were more common in the male cohort (rate/year 3.4% vs. 1.7%; log-rank P = 0.049), while no significant differences in device-related complications (rate/year: 6.3% vs. 5.8%; log-rank P = 0.595) and inappropriate shocks (rate/year: 4.3% vs. 3.1%; log-rank P = 0.375) were observed. After controlling for confounders, sex remained significantly associated with the primary outcome (aHR 1.648; CI 0.999–2.655, P = 0.048), while not resulting predictor of inappropriate shocks and device-related complications.

Conclusion
In a propensity-matched cohort of S-ICD recipients, women are less likely to experience appropriate ICD therapy, while not showing higher risk of device-related complications.

Clinical trial registration
ClinicalTrials.gov Identifier: NCT0473876.