Efficacy, safety, and in-hospital outcomes of subcutaneous versus transvenous implantable defibrillator therapy

Background: Lead-related complication is an important drawback of trans-venous implantable cardioverter-defibrillators (TV-ICD). The subcutaneous ICD (S-ICD) was developed to overcome ICD lead associated complications; however, whether the S-ICD confers enhanced clinical benefits compared with TV-ICD remains unclear. The present systematic review and meta-analysis aimed to assess TV-ICD and S-ICD for safety, efficacy, and in-hospital outcomes in the prevention of sudden cardiac death (SCD) in patients not requiring pacing. Methods: The Medline, PubMed, EmBase, and Cochrane Library databases were searched for studies comparing TV-ICD and S-ICD. Results: A total of 9 eligible studies, including 5 propensity-matched case–control, 3 retrospective, and 1 cross-sectional studies were identified, assessing 7361 patients in all. Pool analyses demonstrated that SICD were associated with lower lead-related complication rates [odds ratio (OR) = 0.13; 95% confidence interval [CI] 0.05–0.33; I 2  = 0%], and S-ICD was more beneficial in terms of reducing ICD shocks [OR = 0.48; 95% CI 0.32–0.72, I 2  = 4%]. In addition, the patients administered S-ICD tend to have shorter length of hospital stay after implantation (SMD = −0.06; 95% CI −0.11 to 0.00, I 2  = 0%) and reduce total complication rates (OR = 0.72; 95% CI 0.50–1.03; I 2  = 18%), non-decreased quality of life (QoL). Moreover, both devices appeared to perform equally well with respect to infection rate and death. Conclusions: Available overall data suggested that S-ICD is associated with reducing lead-related complications, ICD shocks. In addition, S-ICD has tendency to shorten hospitalization and reduce total complications, although the difference is no significant. Equivalent death rate, infection, and QoL were found between 2 groups. Therefore, S-ICD could be considered an alternative approach to TV-ICD in appropriate patients for SCD prevention.