BACKGROUND: Sleep apnea, as measured by polysomnography, is associated with adverse outcomes in heart failure. The DASAP-HF (Diagnosis and Treatment of Sleep Apnea in Patient With Heart Failure) study previously demonstrated that the respiratory disturbance index (RDI) computed by the ApneaScan algorithm (Boston Scientific) accurately identifies severe sleep apnea in implantable cardioverter-defibrillator (ICD) patients.OBJECTIVE: The purpose of the long-term study phase was to assess the incidence of clinical events after 24 months and investigate the association with RDI values.METHODS: Patients with left ventricular ejection fraction ≤35% implanted with an ICD were enrolled and followed-up for 24 months. The RDI calculated at 1 month aft...