Performance of Subcutaneous Implantable Cardioverter Defibrillator (S-ICD) in Chinese Population with Primary Prevention Indications: A Prospective Observational Cohort Study

Background: International studies have shown that use of a subcutaneous implantable cardioverter defibrillator (S-ICD) could reduce lead -related complications while maintaining adequate defibrillation performance; however, data from the Chinese population or other Asian groups are limited. Material/Methods: SCOPE is a prospective, multicenter, observational cohort study. Two hundred patients with primary prevention indication for sudden cardiac death (SCD), who are candidates for S-ICD, will be enrolled. From the same population, another 200 patients who are candidates for transvenous implantable cardioverter defibrillator (TVICD) will be enrolled after being matched for age, sex, SCD high -risk etiology (ischemic cardiomyopathy, and non-ischemic cardiomyopathy, ion channel disease, and other) and atrial fibrillation in a 1: 1 ratio with enrolled S-ICD patients. All the patients will be followed for 18 months under standard of care. Results: The primary endpoint is proportion of patients free from inappropriate shock (IAS) at 18 months in the S-ICD group. The lower 95% confidence bound of the proportion will be compared with a performance goal of 90.3%, which was derived from the previous meta -analysis. The comparisons between S-ICD and TV-ICD on IAS, appropriate shock, and complications will be used as secondary endpoints without formal assumptions. Conclusions: This is the first prospective multicenter study focusing on the long-term performance of S-ICD in a Chinese population. By comparing with the data derived from international historical studies and a matched TV-ICD group, data from SCOPE will allow for the assessment of S-ICD in the Chinese population in a contemporary real -world implantation level and programming techniques, which will help us to further modify the device implantation and programming protocol in this specific population in the future.