Adaptive servoventilation improves cardiac function and respiratory stability

Abstract

Cheyne-Stokes respiration (CSR) in patients with chronic heart failure (CHF) is of major prognostic impact and expresses respiratory instability. Other parameters are daytime pCO₂, VE/VCO₂-slope during exercise, exertional oscillatory ventilation (EOV), and increased sensitivity of central CO₂ receptors. Adaptive servoventilation (ASV) was introduced to specifically treat CSR in CHF. Aim of this study was to investigate ASV effects on CSR, cardiac function, and respiratory stability. A total of 105 patients with CHF (NYHA ≥ II, left ventricular ejection fraction (EF) ≤ 40%) and CSR (apnoea-hypopnoea index ≥ 15/h) met inclusion criteria. According to adherence to ASV treatment (follow-up of 6.7 ± 3.2 months) this group was divided into controls (rejection of ASV treatment or usage <50% of nights possible and/or <4 h/night; n = 59) and ASV (n = 56) adhered patients. In the ASV group, ventilator therapy was able to effectively treat CSR. In contrast to controls, NYHA class, EF, oxygen uptake, 6-min walking distance, and NT-proBNP improved significantly. Moreover, exclusively in these patients pCO₂, VE/VCO₂-slope during exercise, EOV, and central CO₂ receptor sensitivity improved. In CHF patients with CSR, ASV might be able to improve parameters of SDB, cardiac function, and respiratory stability.

Fig. 1

Flow-chart of study population

Fig. 2

Changes in left ventricular ejection fraction (EF) from baseline to follow-up in ASV-treated patients and controls. Top absolute differences (follow-up EF–baseline EF); bottom relative changes compared to baseline EF

Fig. 3

Changes in parameters of respiratory stability. Top daytime capillary pCO₂; middle changes in central CO₂-receptor sensitivity as measured by hyperoxic–hypercapnic ventilatory response (HCVR); bottom changes in VE/VCO₂-slope during cardiopulmonary exercise testing