- Explain to interested patients that long-term continuous positive airway pressure treatment for obstructive sleep apnea can help prevent congestive heart failure, a small study found.
- Note that the study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
SAN ANTONIO -- Long-term continuous positive airway pressure (CPAP) treatment is likely to prevent the development of cardiomyopathy and congestive heart failure in patients with severe obstructive sleep apnea, researchers found.
Six months of CPAP in a group of 32 patients resulted in a drop in left atrial ventricular index from 45 mL/m2 at baseline to 31.75 mL/m2 (P<0.001), according to Saleh Al-Mutairi, MD, and colleagues from the University of Manitoba in Winnepeg.
Moreover, left ventricular end-diastolic dimension decreased from 58.70 mm to 51.21 mm (P<0.001), the researchers reported at the annual meeting of the Associated Professional Sleep Societies.
Accumulating scientific evidence has suggested a strong link between obstructive sleep apnea and cardiac morbidity and mortality, most likely because of left ventricular remodeling.
To study the relationship, Al-Mutairi and colleagues recruited patients with newly diagnosed obstructive sleep apnea diagnosed by split-night polysomnography who had no known cardiac disease.
Patients whose left ventricular ejection fraction was below 50% were excluded.
A total of 93.1% had obstructive sleep apnea that was classified as moderate to severe, with 72% being severe.
Patients' mean age was 51.4 years, mean body mass index was 34.5 kg/m2, and the average apnea-hypopnea index was 53.18.
Echocardiography was performed at baseline, three months, and six months, and cardiac MRI at baseline and six months.
Echocardiographic parameters had already improved by three months, with left atrial ventricular index decreasing from 45 mL/m2 to 34.57 mL/m2 and left ventricular end-diastolic dimension from 58.70 to 52.13 (P<0.001 for both).
By six months, the cardiac MRI changes paralleled the echo findings:
- Left atrial ventricular index, 48.90 mL/m2 to 33.93 mL/m2 (P<0.01)
- Left ventricular end-diastolic volume, 199.24 mL to 149.59 mL (P<0.001)
- Left ventricular mass, 184.28 g/m2 to 149.31 g/m2 (P<0.001)
"These are all important predictors of cardiovascular disease," Al-Mutairi told meeting attendees.
"Our study demonstrated that six months of CPAP resulted in a 30% reduction in left atrial ventricular index, a 25% reduction in left ventricular end-diastolic volume, and a 19% reduction in left ventricular mass, and therefore can be expected to prevent the development of congestive heart failure in patients with severe obstructive sleep apnea," he concluded.
The study was supported by the Sleep Disorders Center, University of Manitoba.
Al-Mutairi declared that he had no conflicts of interest.
Primary source: Associated Professional Sleep Societies
Al-Mutairi S, et al "Improvement in left ventricular removdling in patients with severe OSA following CPAP therapy" APSS 2010; Abstract 332.