OBJECTIVEThe investigate the prevalence of sleep-disordered breathing (SDB) and evaluate its impact on left ventricular remodeling in adult patients with chronic heart failure (CHF).

METHODSAmbulatory sleep recording for 8 h was performed using Embletta PDS (Medcare, Iceland) in 74 patients with CHF, and the left ventricular ejection fraction (LVEF), internal end-diastolic diameter (LVIDd) and left ventricular mass weight (LVMW) were measured using M-mode and two-dimensional echocardiography.

RESULTSThe incidence of SDB defined as an apnea-hypopnea index (AHI, namely the number of apnea-hypopnea events per hour during sleep) no less than 10 was 62.16% in these CHF patients (77.78% in male and 37.93% in female patients). Of the 74 patients 31.1% had mainly obstructive sleep apnea (OSA) and 17.6% had central sleep apnea (CSA). There was a moderate inverse correlation between LVEF and AHI (P=0.004, r=-0.366). LVIDd in patients with CHF and SDB was significantly greater than that in patients with isolated CHF (46.67+/-7.29 vs 55.70+/-11.87 mm, P=0.001). The left ventricular myocardial weight was also greater in patients with CHF and SDB than in patients with isolated CHF (208.58+/-64.19 vs 291.03+/-121.54, P=0.001).

CONCLUSIONOur results suggest a higher prevalence of SDB in patients with CHF than in general population, and the prevalence is even higher in patients with severe CHF in relation to left ventricular remodeling. SDB contributes to the progression of CHF and further cardiac decline by a vicious cycle.