Purpose: Adaptive servo-ventilation (ASV) therapy has been reported to be effective for improving central sleep apnea (CSA) and chronic heart failure (CHF). The purpose of this study was to clarify whether ASV is effective for CSA, cardiac sympathetic nerve activity (CSNA), cardiac symptoms/function, and exercise capacity in CHF patients with CSA and Cheyne-Stokes respiration (CSR-CSA).
Methods: In this study, 31 CHF patients with CSR-CSA and a left ventricular ejection fraction (LVEF) ≤ 40% were randomized into an ASV group and a conservative therapy (non-ASV) group for 6 month. Nuclear imagings with 123I-Metaiodobenzylguanidine (MIBG) and 99mTc-Sestamibi were performed. Exercise capacity using a specific activity scale (SAS) and the New York Heart Association (NYHA) class were evaluated. CSNA was evaluated by 123I-MIBG imaging, with the delayed heart/mediastinum activity ratio (H/M), delayed total defect score (TDS), and washout rate (WR).
Results: The ASV group had significantly better (P < .05) results than the non-ASV group with respect to the changes of AHI (-20.8 ± 14.6 vs -0.5 ± 8.1), TDS (-7.9 ± 4.3 vs 1.4 ± 6.0), and H/M(0.16 ± 0.16 vs -0.04 ± 0.10) on 123I-MIBG imaging, as well as the changes of LVEF (5.3 ± 3.9% vs 0.7 ± 32.6%), SAS (1.6 ± 1.4 vs 0.3 ± 0.7), and NYHA class (2.2 ± 0.4 vs 2.7 ± 0.5) after 6-month therapy.
Conclusions: Performing ASV for 6 months achieved improvement of CSR-CSA, CSNA, cardiac symptoms/function, and exercise capacity in CHF patients with CSR-CSA.
Keywords: Adaptive servo-ventilation; cardiac sympathetic nerve activity; chronic heart failure and cheyne-Stokes respiration.