Ventricular arrhythmia, Cheyne-Stokes respiration, and death: observations from patients with defibrillators

OBJECTIVE: To determine whether ventricular arrhythmia related to nocturnal hypoxaemia during Cheyne-Stokes respiration (CSR) explains the observation that CSR is an independent marker of death in heart failure. DESIGN: Prospective, observational study. PATIENTS: 101 patients at high risk of clinical serious ventricular arrhythmia fitted with an implantable cardioverter-defibrillator (ICD). MEASUREMENTS: Patients were studied at baseline for CSR during sleep. Arrhythmia requiring device discharge was used as a surrogate marker for possible sudden cardiac death. RESULTS: 101 patients (42 with CSR) were followed up for a total of 620 months. Twenty six patients experienced 432 ICD discharge episodes. Twenty four (6%), 210 (49%), 125 (29%), and 73 (17%) episodes occurred across the time quartiles 0000-0559, 0600-1159, 1200-1759, and 1800-2359, respectively. Kaplan-Meier analysis showed a relative risk of 1 (95% confidence interval 0.5 to 2.2, p = 1) for device discharge in the CSR group. The average (SED) numbers of nocturnal ICD discharges per patient per month of follow up were 0.01 (0.01) and 0.04 (0.02) for patients with and without CSR, respectively (p = 0.6). CONCLUSION: These findings refute the proposition that CSR is related to heart failure death through nocturnal serious ventricular arrhythmia.