ObjectivesWe studied the effects of cardiac resynchronization therapy (CRT) on heart failure (HF) patients with central sleep apnea (CSA). BackgroundPatients with advanced HF often suffer from CSA with Cheyne-Stokes respiration. Cardiac resynchronization therapy improves myocardial function and exercise capacity in HF patients with conduction disturbances. The relationship between CRT and CSA is currently unknown. MethodsTwenty-four patients (7 females; 62 ± 11 years) with HF, a reduced left ventricular ejection fraction (24 ± 6%), and left bundle branch block (QRS duration 173 ± 22 ms) received a CRT device. The number of apneas and hypopneas per hour (apnea-hypopnea index [AHI]) and minimal oxygen saturation (Sao2min) were quantified by cardiorespiratory polygraphy. Fourteen patients showed CSA (AHI >5/h), and 10 patients had an AHI <5/h without CSA. Subjective sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI). Data were evaluated before and after 17 ± 7 weeks of CRT. ResultsIn patients with CSA, CRT led to a significant decrease in AHI (19.2 ± 10.3 to 4.6 ± 4.4, p < 0.001) and PSQI (10.4 ± 1.6 to 3.9 ± 2.4, p < 0.001) without Cheyne-Stokes respiration and to a significant increase in Sao2min (84 ± 5% to 89 ± 2%, p < 0.001). There was no significant change in AHI (1.7 ± 0.7 to 1.5 ± 1.6), PSQI (2.4 ± 0.5 to 2.6 ± 0.9), and Sao2min (90 ± 2% to 91 ± 1%) in patients without CSA. ConclusionsCardiac resynchronization therapy leads to a reduction of CSA and to increased sleep quality in patients with HF and sleep-related breathing disorders. This may have prognostic implications in patients receiving CRT.