Omran H, et al. - In this retrospective analysis, researchers focused on the occurrence and circadian distribution of ventricular arrhythmias in heart failure with reduced ejection fraction (HFrEF) patients with and without sleep-disordered breathing (SDB). They used 24-hour Holter-ECG data and the apnea–hypopnea index (AHI) to express respiratory events. An AHI ≥ 15/h was categorized as moderate to severe SDB. Central sleep apnea (CSA) was found to be related to VT occurrence regardless of sleep/wake status in HFrEF patients. Furthermore, it independently predicted the occurrence of VT. Findings suggested a possible contribution of this association to chances by which CSA increases sudden death risk in HFrEF patients.