Inappropriate shocks in ICD/CRT-D patients: are they as harmful as we think?

Introduction While implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy defibrillators (CRT-Ds) are effective in preventing sudden death, they are associated with complications, including inappropriate shocks, which have been thought to negatively impact quality of life and prognosis. Objectives This study aimed to evaluate differences in outcomes between patients with and without inappropriate shocks and identify potential predictors of inappropriate shock occurrence. Methods A retrospective analysis between 2020 and 2024 included 264 patients who underwent ICD/CRT-D implantation. Data collected encompassed demographic characteristics, cardiovascular risk factors, documented arrhythmias, medical therapy, etiology, prevention type, and device mode. Outcomes analyzed were hospitalization due to heart failure, myocardial infarction, stroke, or death. Predictors of inappropriate shocks were identified using multivariate logistic regression. Results Of the 264 patients, data on inappropriate shocks were available for 220, with 4% experiencing inappropriate shocks. The sample comprised predominantly men (78.8%) with a median age of 66 (58–73) years. Characteristics between the two groups (with vs. without inappropriate shocks) were largely similar, including device type, with the exception of higher hospitalization rates in the group of patients with inappropriate shocks (33.3% vs. 5.6%, p=0.016). Composite outcomes showed no significant differences between groups. Predictors of inappropriate shocks included age (OR=0.940, 95% CI: 0.886–0.997, p=0.039) and atrial fibrillation (OR=5.279, 95% CI: 1.021–27.286, p=0.047). Conclusion Despite the psychological and economic burden on the healthcare system, inappropriate shocks were not associated with adverse outcomes in this study. However, younger age and atrial fibrillation were identified as predictors of inappropriate shocks. These findings underscore the importance of aggressive atrial fibrillation management (rhythm/heart rate control) and careful optimization of device programming, particularly in younger patients.