Abstract 3722: Multimodality Cardiovascular Imaging Detects Improvment Of Subclinical Microvascular Dysfunction With Continuous Positive Airway Pressure Therapy In Obstructive Sleep Apnea Patients: A Prospective, Randomized, Double-blinded Study
Background: Several observational studies suggest that obstructive sleep apnea (OSA) is associated with an increased risk of cardiovascular disease. However, there is little data on early subclinical development of cardiovascular disease in OSA patients.
Hypothesis: We tested the hypothesis that continuous positive airway pressure (CPAP) improves subclinical cardiovascular disease in OSA patients.
Methods: Sixteen consecutive patients diagnosed with moderate to severe OSA were recruited into a double-blinded, prospective study. Multimodality cardiovascular imaging (CVI) studies (cardiac MRI, echocardiography, and vascular ultrasound) were performed to assess LV mass, LV and RV ejection fraction (EF), adenosine stress myocardial perfusion reserve (MPR), nitroglycerin mediated coronary vasoreactivity, and flow-mediated vasodilatation (FMD) of the brachial artery. Patients were randomized to either CPAP or sham CPAP therapy and monitored for compliance during the entire period of treatment. After 3 months of therapy, they underwent follow-up CVI studies to assess development of subclinical cardiovascular disease.
Results: MPR significantly improved (p=0.02) in patients with CPAP therapy compared to those without. Similarly, FMD of brachial artery improved significantly (p=0.04) following CPAP therapy. No significant differences were observed in LV mass (p=0.31), LV EF (p=0.17), RV EF (p=0.09), LV diastolic function (E/A) (p=0.67), and coronary vasoreactivity (p=0.25) between the two groups.
Conclusions: Impairment of endothelial dependent FMD, and MPR, surrogate markers of microvascualr function, has been shown to be the subclinical cardiovascular effects in OSA patients. Our findings suggest that CPAP therapy may prevent the progression of subclinical cardiovascular disease in OSA patients.