An Overview of Clinical Outcomes in Transvenous and Subcutaneous ICD Patients

Clear guidelines on when to select a subcutaneous ICD (S-ICD) over a transvenous ICD (TV-ICD) are lacking. This review will provide an overview of the most recent clinical data on S-ICD and TV-ICD therapy by pooling comparison studies in order to aid clinical decision making.

Pooling of observational-matched studies demonstrated an incidence rate ratio (IRR) for device-related complication of 0.90 (95% CI 0.58-1.42) and IRR for lead-related complications of 0.15 (95% CI 0.06-0.39) in favor of S-ICD. The IRR for device infections was 2.00 (95% CI 0.95-4.22) in favor of TV-ICD. Both appropriate shocks (IRR 0.67 (95% CI 0.42-1.06)) and inappropriate shocks (IRR 1.17 (95% CI 0.77-1.79)) did not differ significantly between both groups. With randomized data underway, the observational data demonstrate that the S-ICD is associated with reduced lead complications, but this has not yet resulted in a significant reduction in total number of complications compared to TV-ICDs. New technologies are expected to make the S-ICD a more attractive alternative.