Aims: The aim of this first large-scale long-term study was to investigate whether obstructive sleep apnoea (OSA) and/or central sleep apnoea (CSA) are associated with an increased risk of malignant cardiac arrhythmias in patients with congestive heart failure (CHF).
Methods and results: Of 472 CHF patients who were screened for sleep disordered breathing (SDB) 6 months after implantation of a cardiac resynchronization device with cardioverter-defibrillator, 283 remained untreated [170 with mild or no sleep disordered breathing (mnSDB) and 113 patients declined ventilation therapy] and were included into this study. During follow-up (48 months), data on appropriately monitored ventricular arrhythmias as well as appropriate cardioverter-defibrillator therapies were obtained from 255 of these patients (90.1%). Time period to first monitored ventricular arrhythmias and to first appropriate cardioverter-defibrillator therapy were significantly shorter in patients with either CSA or OSA. Forward stepwise Cox models revealed an independent correlation for CSA and OSA regarding monitored ventricular arrhythmias [apnoea-hypopnoea index (AHI) ≥5 h(-1): CSA HR 2.15, 95% CI 1.40-3.30, P < 0.001; OSA HR 1.69, 95% CI 1.64-1.75, P = 0.001; AHI ≥15 h(-1): CSA HR 2.06, 95% CI 1.40-3.05, P < 0.001; OSA HR 1.69, 95% CI 1.14-2.51, P = 0.02] and appropriate cardioverter-defibrillator therapies (AHI ≥5 h(-1): CSA HR 3.24, 95% CI 1.86-5.64, P < 0.001; OSA HR 2.07, 95% CI 1.14-3.77, P = 0.02; AHI ≥15 h(-1): CSA HR 3.41, 95% CI 2.10-5.54, P < 0.001; OSA HR 2.10, 95% CI 1.17-3.78, P = 0.01).
Conclusion: In patients with CHF, CSA and OSA are independently associated with an increased risk for ventricular arrhythmias and appropriate cardioverter-defibrillator therapies.