Clinical outcomes of subcutaneous vs. transvenous implantable defibrillator therapy in a polymorbid patient cohort

Badder Kattih; Felix Operhalski; Felicitas Boeckling; Florian Hecker; Felix Michael; Mate Vamos; Stefan H Hohnloser; Julia W Erath

doi:10.3389/fcvm.2022.1008311

Clinical outcomes of subcutaneous vs. transvenous implantable defibrillator therapy in a polymorbid patient cohort

Front Cardiovasc Med. 2022 Oct 18:9:1008311. doi: 10.3389/fcvm.2022.1008311. eCollection 2022.

Authors

Badder Kattih¹, Felix Operhalski¹, Felicitas Boeckling¹, Florian Hecker², Felix Michael¹, Mate Vamos³, Stefan H Hohnloser¹, Julia W Erath¹

Affiliations

¹ Division of Clinical Electrophysiology, Department of Cardiology, University Hospital Frankfurt, J. W. Goethe University, Frankfurt am Main, Germany.
² Department of Cardiac Surgery, University Hospital Frankfurt, J. W. Goethe University, Frankfurt am Main, Germany.
³ Cardiac Electrophysiology Division, Department of Internal Medicine, University of Szeged, Szeged, Hungary.

Abstract

Background: The subcutaneous implantable cardioverter-defibrillator (S-ICD) has been designed to overcome lead-related complications and device endocarditis. Lacking the ability for pacing or resynchronization therapy its usage is limited to selected patients at risk for sudden cardiac death (SCD).

Objective: The aim of this single-center study was to assess clinical outcomes of S-ICD and single-chamber transvenous (TV)-ICD in an all-comers population.

Methods: The study cohort comprised a total of 119 ICD patients who underwent either S-ICD (n = 35) or TV-ICD (n = 84) implantation at the University Hospital Frankfurt from 2009 to 2017. By applying an inverse probability-weighting (IPW) analysis based on the propensity score including the Charlson Comorbidity Index (CCI) to adjust for potential extracardiac comorbidities, we aimed for head-to-head comparison on the study composite endpoint: overall survival, hospitalization, and device-associated events (including appropriate and inappropriate shocks or system-related complications).

Results: The median age of the study population was 66.0 years, 22.7% of the patients were female. The underlying heart disease was ischemic cardiomyopathy (61.4%) with a median LVEF of 30%. Only 52.9% had received an ICD for primary prevention, most of the patients (67.3%) had advanced heart failure (NYHA class II-III) and 16.8% were in atrial fibrillation. CCI was 5 points in TV-ICD patients vs. 4 points for patients with S-ICD (p = 0.209) indicating increased morbidity. The composite endpoint occurred in 38 patients (31.9 %), revealing no significant difference between patients implanted with an S-ICD or TV-ICD (unweighted HR 1.50, 95 % confidence interval (CI) 0.78-2.90; p = 0.229, weighted HR 0.94, 95% CI, 0.61-1.50, p = 0.777). Furthermore, we observed no difference in any single clinical endpoint or device-associated outcome, neither in the unweighted cohort nor following inverse probability-weighting.

Conclusion: Clinical outcomes of the S-ICD and TV-ICD revealed no differences in the composite endpoint including survival, freedom of hospitalization and device-associated events, even after careful adjustment for potential confounders. Moreover, the CCI was evaluated in a S-ICD cohort demonstrating higher survival rates than predicted by the CCI in young, polymorbid (S-)ICD patients.

Keywords: S-ICD; TV-ICD; implantable cardioverter-defibrillator (ICD); subcutaneous ICD; sudden cardiac death; transvenous ICD.