METHODS AND RESULTS: MEDLINE, EMBASE, and clinicaltrials.gov databases were searched to identify relevant studies. Those that followed patients for ≥6 months and reported mortality were included. Six met the inclusion criteria; 4 randomized (Comparison of Empiric to Physician-Tailored Programming of ICDs [EMPIRIC], Multicenter Automatic
Defibrillator Implantation Trial-Reduce Inappropriate
Therapy [MADIT-RIT], Avoid Delivering
Therapies for Non-sustained Arrhythmias in ICD Patients III [ADVANCE III], and Programming
Implantable Cardioverter-Defibrillators in Patients with Primary Prevention Indication to Prolong Time to First
Shock [PROVIDE]) and 2 prospective studies (Role of Long Detection Window Programming in Patients With
Left Ventricular Dysfunction, Non-ischemic Etiology in Primary Prevention Treated with a Biventricular ICD [RELEVANT] and Primary Prevention Parameters Evaluation [PREPARE]). These 6 studies included 7687 (3598 conventional and 4089
therapy reduction programming) patients. Most (77%) participants were men, had a history of
ischemic heart disease (56%), and were prescribed β-blockers (84%).
Therapy reduction programming was associated with a 30% relative reduction in mortality (95% confidence interval, 16%-41%; P<0.001). No significant heterogeneity among studies was observed (P=0.6). A similar 26% reduction in mortality was observed when only the 4 randomized trials were included (95% confidence interval, 11%-40%; P=0.002). These results were not significantly altered after adjustment for baseline characteristics. No significant difference in the risk of
syncope was observed with conventional versus
therapy reduction programming (P=0.5).
CONCLUSIONS:
Therapy reduction programming results in a large, significant, and consistent reduction in mortality, with no apparent increase in the risk of
syncope.