Background: Sleep-disordered breathing is common in individuals with left ventricular (LV) dysfunction and has been treated with nocturnal positive airway pressure. We investigated whether treatment of central sleep apnea-hypopnea with bilevel positive airway pressure (BPAP) in ambulatory patients with idiopathic dilated cardiomyopathy (IDCM) might improve LV function.
Methods: Fifty-two consecutive patients with IDCM who underwent both cardiac catheterization and standard polysomnography were enrolled in the study; individuals with obstructive sleep apnea syndrome were excluded. Subjects with an apnea-hypopnea index (AHI) >or= 20 episodes per hour were randomized to receive medical therapy either alone (n = 11) or together with BPAP (n = 10).
Results: LV end-diastolic pressure, pulmonary capillary wedge pressure, and plasma concentration of brain natriuretic peptide were significantly greater, and LV ejection fraction (LVEF) was significantly lower in patients with an AHI >or= 20/h (n = 21, 40.4%) than in those with an AHI < 20/h (n = 31, 59.6%). LVEF (30.5 +/- 1.6% vs 50.8 +/- 3.5%, p < 0.001) [mean +/- SE] and plasma concentration of brain natriuretic peptide (162.8 +/- 44.5 pg/mL vs 32.7 +/- 17.6 pg/mL, p = 0.02) were significantly increased and decreased, respectively, after treatment with BPAP (daily use, 4.8 +/- 0.3 h) for 3 months, whereas these parameters remained unchanged in the control subjects.
Conclusions: Our findings suggest that treatment of coexisting central sleep apnea-hypopnea with BPAP improves LV function in ambulatory patients with IDCM. BPAP should thus be considered as a nonpharmacologic adjunct to conventional drug therapy in such patients.