Abstract 4856: Could a Simplified Biventricular Icd Device be Safe and Effective in Patients with Non-Ischemic Heart Failure? Results from the Relevant Study
Background & Aim: Ventricular tachyarrhythmia (VT) in patients (pts) with non-ischemic (NI) heart failure (HF) treated with biventricular ICD (CRT-D) is ill-defined. This study investigated effectiveness and safety of a CRT-D device with simplified VT management (fixed shock capacity, 30/40 NID detection, single burst ATP in fast-VT window, “monitor only” VT window) in pts with NI HF and primary prevention (PP) ICD indication.
Methods: Prospective, controlled, parallel, multicenter study. Pts enrolled (n.324), between March 2004-September 2007, had NI HF and PP ICD indication: 164 patients were implanted with Medtronic Insync III Protect devices (Protect gp, with fixed ICD features); the other 160 patients were implanted with other Medtronic CRT-D devices (tailored ICD programming, Control group). Appropriate and inappropriate detections and therapies were computed; cardiovascular (CV) and syncopal events were recorded.
Results: No significant differences in baseline variables or in mean follow-up (mean 14 months) were detected between the groups. Inter- and intragroup analysis of detected episodes allowed to observe that, in Protect group, more than 90% of both ventricular (282/310) and supraventricular (225/242) tachyarrhythmias were found to terminate within the 13–29 beats. Kaplan Meier analysis showed significantly better survival to first delivered therapy in Protect arm for all treated episodes (p=.0001), for appropriate treated episodes (p=.002), and for inappropriate treated episodes (p=.017). Freedom from first shock delivered appropriately (p=.578) or inappropriately (p=.128) were not significantly different between groups, but the total number of shocks delivered in each group differed significantly (Protect: 21 vs Control 57, p=.01), suggesting greater shock burden in Control group. Moreover, the Protect algorithm did not increase adverse events such as syncope, but, on the contrary, CV morbidity and mortality risk was significantly lower in the Protect group (HR 0.26, [0.11– 0.65], p=.004).
Conclusions: A cheaper, easy-to-program CRT-D device with fixed long detection reduced overall ICD therapy burden without entailing any additional adverse events in pts with NI HF and PP ICD indication.