Effect of continuous positive airway pressure on ventricular ectopy in heart failure patients with obstructive sleep apnoea.
BACKGROUND
Obstructive sleep apnoea (OSA) elicits a number of cardiovascular perturbations that could lead acutely or chronically to increased ventricular ectopy in patients with heart failure (HF). We tested the hypothesis that treatment of OSA with continuous positive airway pressure (CPAP) in patients with HF would reduce the frequency of ventricular premature beats (VPBs) during sleep in association with reduced sympathetic nervous system activity.


METHODS
Following optimisation of medical treatment, 18 HF patients with OSA and >10 VPBs per hour of sleep were randomised to a control group (n = 8) or a treatment group who received CPAP (n = 10). The frequency of VPBs and urinary norepinephrine (noradrenaline) concentrations during total sleep time were determined at baseline and after 1 month.


RESULTS
Control patients did not experience any significant changes in apnoea-hypopnoea index (AHI), mean nocturnal O(2) saturation, or the frequency of VPBs. In contrast, there was a significant reduction in AHI (p<0.001), an increase in minimum O(2) saturation (p = 0.05), a reduction in urinary norepinephrine concentrations (p = 0.009), and a 58% reduction in the frequency of VPBs during total sleep (from mean (SE) 170 (65) to 70 (28) per hour, p = 0.011) after 1 month of CPAP treatment.


CONCLUSIONS
In patients with HF, treatment of co-existing OSA by CPAP reduces the frequency of VPBs during sleep. These data suggest that reductions in VPBs and other ventricular arrhythmias through treatment of OSA might improve the prognosis in patients with HF.
Toronto General Hospital/University Health Network, EC 6-248, 200 Elizabeth Street, Toronto, Ontario M5G 2C4, Canada.
C M
CM
Ryan
K
K
Usui
J S
JS
Floras
T D
TD
Bradley
D001145:Arrhythmias, Cardiac / Q000191:economics / Q000628:therapy*; D045422:Continuous Positive Airway Pressure / Q000379:methods*; D005260:Female; D006333:Heart Failure / Q000150:complications*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000150:complications*; D018754:Ventricular Dysfunction / Q000191:economics / Q000628:therapy*