Rationale and design of a randomized clinical trial comparing stress reduction treatment to usual cardiac care: The reducing vulnerability to implantable cardioverter defibrillator shock-treated ventricular arrhythmias (RISTA) trial

Objective: To present the design of a multicenter, randomized trial testing the effects of stress reduction treatment (SRT) on the prevalence of shock-treated ventricular arrhythmias among patients with an implantable cardioverter defibrillator (ICD). Significant adjustment problems secondary to ICD shock can increase the likelihood of arrhythmias requiring shock for termination. Whether SRT can reduce arrhythmias requiring shock for termination in patients with ICDs has not been tested in clinical trials. Methods: New ICD recipients and previous recipients who have received an appropriate therapeutic shock in the last 6 months (n = 304) will be enrolled and randomized to either SRT or usual cardiac care. Participants complete a psychosocial questionnaire and undergo laboratory mental stress testing and 24-hour Holter monitoring with diary at study entry and approximately 4 months later. Follow-ups are completed at 6, 12, and 24 months post randomization to assess occurrence of ICD shock for ventricular arrhythmias (primary outcome), antitachycardia pacing events, medication changes, hospitalizations, deaths, and quality of life. Results: Log-rank test and Cox proportional hazards model will be used to test the effects of SRT on time to first shock-treated ventricular arrhythmia, with exploratory analyses testing the effects on overall frequency of ventricular arrhythmia. Secondary analyses will test the effects of SRT on laboratory stress-induced and 24-hour arrhythmogenic electrophysiological indices from pre to post treatment, and both quality of life and measures of anger across the 2 years of the study. Conclusions: The Reducing Vulnerability to ICD Shock-Treated Ventricular Arrhythmias (RISTA) Trial is the first large-scale, randomized, clinical trial designed to evaluate the effect of SRT on the prevalence of shock-treated arrhythmias among patients with an ICD. Results may demonstrate a treatment that can reduce vulnerability to arrhythmia-provoked shock and improve quality of life.