Continuous positive airway pressure therapy reduces right ventricular volume in patients with obstructive sleep apnea: a cardiovascular magnetic resonance study.
OBJECTIVE
There are few data on the effects of continuous positive airway pressure (CPAP) therapy on the structural and functional characteristics of the right heart in patients with obstructive sleep apnea (OSA). We sought to leverage the advantages of cardiac magnetic resonance imaging (CMR) and hypothesized that CPAP treatment would improve right ventricular (RV) function in a group of patients with OSA who were free of other comorbid conditions.


METHODS
Patients with severe (apnea-hypopnea index > or = 30/h) untreated OSAwere prospectively enrolled. CMR included 3-dimensional measurement of biventricular size and function, and rest/stress myocardial perfusion and was performed at baseline and after 3 months of CPAP therapy.


RESULTS
Fifteen patients with mild to moderate desaturation were enrolled; 2 could not undergo CMR due to claustrophobia and obesity. There were significant decreases in the Epworth Sleepiness Scale score (p < 0.0001) and RV end-systolic and RV end-diastolic volumes (p < 0.05) with CPAP. There was a trend toward improvement in RV ejection fraction, but the improvement did not reach statistical significance. Other measures such as left ventricular volumes, left ventricular ejection fraction, myocardial perfusion reserve index, and thickness of the interventricular septum and ventricular free wall did not change significantly.


CONCLUSIONS
This preliminary study found that CPAP treatment decreases RV volumes in patients with severe OSA who are otherwise healthy. CMR offers a novel technique to determine the effects of CPAP on ventricular structure and function in patients with OSA. A randomized controlled study is needed to confirm the results of our study.
Magalang
Ulysses J
UJ
Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, The Ohio State University, Columbus, Ohio 43210, USA.
Richards
Kathryn
K
McCarthy
Beth
B
Fathala
Ahmed
A
Khan
Meena
M
Parinandi
Narasimham
N
Raman
Subha V
SV
D000328:Adult; D000368:Aged; D045422:Continuous Positive Airway Pressure; D005260:Female; D006334:Heart Function Tests; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000628:therapy*; D018497:Ventricular Dysfunction, Right / Q000150:complications / Q000503:physiopathology / Q000628:therapy*