Clinical Implications of Non-Sustained Ventricular Tachycardia in the Indication for Primary Prevention With an Implantable Cardioverter Defibrillator - Subanalysis From the Japanese Heart Failure and Sudden Cardiac Death Prevention Trial (HINODE).

Background: The usefulness of non-sustained ventricular tachycardia (NSVT) in predicting sudden cardiac death is not clear. The Heart Failure Indication and Sudden Cardiac Death Prevention Trial Japan (HINODE) investigated the effectiveness of implantable cardioverter defibrillator (ICD) treatment for primary prevention in Japanese patients. This subanalysis examined associations between NSVT and clinical outcomes.

Methods and results: Patients with ICD/cardiac resynchronization therapy defibrillator (CRT-D) for primary prevention (n=164) were divided into NSVT (n=25) and no NSVT (n=139) groups. NSVT was defined as ventricular tachycardia of <30 s duration regardless of pulse rate. The median follow-up period was 19 months, mean patient age was 67 years, and 21% of patients were female. There were no significant differences between the 2 groups in the frequency ischemic cardiomyopathy, mean left ventricular ejection fraction, or (in Kaplan-Meier analysis) in all-cause mortality (log-rank P=0.613), ventricular arrhythmia (VA; log-rank P=0.282), or the composite endpoint of all-cause death and VA events (log-rank P=0.352). Cox proportional hazards analysis indicated that NSVT was not a prognostic factor.

Conclusions: Prognosis was similar between the NSVT and no NSVT groups. NSVT, although recommended in guidelines for risk stratification, was not associated with appropriate ICD therapy in patients with ICD/CRT-D for primary prevention. The utility of NSVT in guiding ICD indication may depend on its definition and the characteristics of the studied population, and requires further investigation.