The coexistence of obstructive sleep apnea (OSA) and central sleep apnea (CSA) and Cheyne-Stokes respiration (CSR) is common in patients with heart failure (HF). While CPAP improves CSA/CSR by about 50%, maximal suppression is crucial in improving clinical outcomes. Auto-servoventilation (ASV) effectively suppresses CSA/CSR in HF, but few trials have been performed in patients with coexisting OSA and CSA/CSR. Our objective was to evaluate a randomized, controlled trial to compare the efficacy of ASV and CPAP in reducing breathing disturbances and improving cardiac parameters in patients with HF and coexisting sleep-disordered breathing.
Both modes were delivered using the BiPAP autoSV (Philips Respironics) over a 12-month period. Seventy patients (63 men, 66.3 ± 9.1 y, BMI 31.3 ± 6.0 kg/m2) had coexisting OSA and CSA/CSR, arterial hypertension, coronary heart disease, or cardiomyopathy and clinical signs of heart failure New York Heart Association classes II-III. Polysomnography, brain natriuretic peptide (BNP), spiroergometry, and echocardiography were performed at baseline and after 3 and 12 months of treatment.
Both modes of therapy significantly improved respiratory disturbances, oxygen desaturations, and arousals over the study period. ASV reduced the central apnea hypopnea index (baseline CPAP, 21.8 ± 11.7; ASV, 23.1 ± 13.2; 12 months CPAP, 10.7 ± 8.7; ASV, 6.1 ± 7.8, P < .05) and BNP levels (baseline CPAP, 686.7 ± 978.7 ng/mL; ASV, 537.3 ± 891.8; 12 months CPAP, 847.3 ± 1848.1; ASV, 230.4 ± 297.4; P < .05) significantly more effectively as compared with CPAP. There were no relevant differences in exercise performance and echocardiographic parameters between the groups.
ASV improved CSA/CSR and BNP over a 12-month period more effectively than CPAP.
ISRCTN Registry; No: ISRCTN70594408; URL: www.controlled-trials.com