Watanabe Masaya, Nanbu Tadafumi, Ishidoya Yuki, Suzuki George, Yotsukura Akihiko, Yoshida Izumi, Tanaka Yoshitaka, Inoue Kazushige, Mitsuishi Junko, Kanno Tomomi, Sakurai Masayuki, Anzai Toshihisa
Department of Cardiovascular Medicine, Hokko Memorial Hospital, Sapporo, Japan.
Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan.
Pacing Clin Electrophysiol. 2025 Feb;48(2):160-168. doi: 10.1111/pace.15151. Epub 2025 Jan 27.
This study aimed to compare inappropriate shock (IAS) rates between subcutaneous implantable cardioverter-defibrillator (S-ICD) and transvenous ICD (TV-ICD) in Brugada syndrome (BrS) patients and identify risk factors for IAS in S-ICD use.
We enrolled consecutive patients with BrS who underwent ICD implantation between 2013 and 2023. Data on clinical characteristics, S-ICD screening test data, and IAS occurrence were retrospectively analyzed.
In total, 74 patients (40 with S-ICDs and 34 with TV-ICD) were enrolled in the study. During a median follow-up of 4.6 years, IAS occurred in nine S-ICD and three TV-ICD patients, exhibiting a non-statistically significant trend (log-rank p = 0.103) toward a higher incidence in the S-ICD group. The incidence of IAS related to non-atrial tachyarrhythmia (non-AT) causes was significantly higher in the S-ICD group than in the TV-ICD group (log-rank p = 0.014). Fewer electrocardiography (ECG) sensing vectors passing the screening test at both the baseline and exercise test (hazard ratio [HR] 0.31, 95% confidence interval [CI] 0.09-0.85; p = 0.21) and detection of ATs (HR 5.25, 95% CI 1.15-24.05; p = -0.048) were associated with IAS in patients with S-ICD.
No significant difference was observed in the overall incidence of IAS between the S-ICD and TV-ICD groups; however, IAS due to non-AT causes occurred more frequently in the S-ICD group. Fewer ECG sensing vectors passing screening were significantly correlated with the IAS when exercise test results were considered. Therefore, ECG screening, including exercise testing, is preferable for S-ICD candidates.
