Continuous Positive Airway Pressure Therapy Restores Cardiac Mechanical Function in Patients With Severe Obstructive Sleep Apnea: A Randomized, Sham-Controlled Study.

BACKGROUND: Continuous positive airway pressure (CPAP) therapy might decrease left ventricular (LV) and right ventricular (RV) loads and improve cardiac mechanical function in patients with obstructive sleep apnea (OSA). However, the benefits of CPAP therapy for cardiac mechanical function in patients with OSA have not previously been proved in a randomized, sham-controlled clinical trial. This study therefore investigated the effects of CPAP therapy on LV and RV mechanical function in patients with severe OSA and compared them with the effects of a sham intervention.

METHODS: In this randomized sham-controlled trial, we analyzed LV and RV function by conventional and speckle-tracking echocardiography before and after 3 months of treatment in 52 patients with severe OSA. Patients were randomly assigned (1:1) to receive either CPAP or sham treatment for 3 months. The main investigator and patients were masked to the trial randomization.

RESULTS: After 3 months, CPAP treatment significantly improved LV global longitudinal strain (GLS) compared with the sham treatment (-20.0% ± 2.1% vs -18.0% ± 2.5%; P = .004), although there were no differences in LV dimension or ejection fraction. CPAP treatment reduced RV size and improved the fractional area change (51.3% ± 7.9% vs 46.9% ± 6.7%; P = .038) compared with the sham treatment. CPAP treatment did not ameliorate the RV GLS compared with the sham treatment.

CONCLUSIONS: In patients with severe OSA, CPAP treatment for 3 months improved LV and RV function compared with sham treatment. LV mechanical function assessed by speckle-tracking echocardiography and RV fractional area change assessed by two-dimensional echocardiography were significantly improved by CPAP treatment.