"Clinical Question"
In patients with an indication for an implantable cardioverter-defibrillator (ICD) but no indication for pacing, is the subcutaneous ICD noninferior to the transvenous ICD with respect to device-related complications and inappropriate shocks?

"Bottom Line"
The subcutaneous ICD was noninferior to the transvenous ICD regarding device-related complications and inappropriate shocks in patients requiring ICD implantation without pacing indications.

"Major Points"


"Guidelines"
Current guidelines recommend ICD therapy for the primary prevention of sudden cardiac death in specific patient populations at high risk and for secondary prevention in patients who have survived a cardiac arrest or sustained ventricular arrhythmia.

"Design"


"Population"
A total of 849 patients were included in the analysis, with 426 assigned to receive a subcutaneous ICD and 423 to receive a transvenous ICD.

"Interventions"
Patients were randomly assigned to receive either a subcutaneous ICD or transvenous ICD according to 1:1 allocation.

"Outcomes"
The primary endpoint was a composite of device-related complications and inappropriate shocks. Secondary endpoints included death, appropriate shocks, major adverse cardiac events, and hospitalization for heart failure.

"Criticisms"
- The clinical-events committee was aware of the trial-group assignments, potentially introducing bias.
- Device technology advancements during the trial may affect applicability of results.
- Shorter experience with subcutaneous ICD implantation compared to transvenous ICD.

"Funding"
The trial was funded by Boston Scientific.

"Further Reading"
The full text of the study and related materials can be accessed at NEJM.org with the ClinicalTrials.gov number NCT01296022.