Could Fibrosis Predict Cardiac Risk in Patients with OSA?

Myocardial fibrosis could serve as an effective predictor of adverse cardiovascular events in patients with obstructive sleep apnea (OSA), according to the results of a recent study.

"Fibrosis in the heart disrupts its normal architecture and function ultimately leading to cardiovascular morbidity and mortality,” the researchers explained. “Patients with cardiovascular disease are at two to three times higher risk of having OSA. We hypothesized that quantifying myocardial fibrosis in patients with OSA could help identify those at increased risk of adverse cardiovascular outcomes."
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For their study, the researchers followed 1094 patients referred for cardiac magnetic resonance testing because of known or suspected disease. Of these patients, 324 had OSA. The researchers also included 16 healthy patients as a control group.

Overall, the researchers found that 30% of patients with OSA had a high degree of myocardial fibrosis—higher than healthy controls but similar to patients with known or suspected heart disease. After 2.3 years of follow-up, no difference was observed in the rates of heart failure hospitalization or death between OSA and non-OSA patients, but in those patients with OSA, myocardial fibrosis was significantly associated increased risk of cardiovascular events, even after adjusting for age, kidney function, and ejection fraction. Each 5% increase in extracellular volume fraction was associated with a 1.6 times higher risk of heart failure hospitalization or death.

"Large clinical trials are needed to determine if using anti-fibrotic medications in patients with myocardial fibrosis identified by CMR improves cardiovascular outcomes,” they concluded. “Ultimately, this is about better defining each patient's true risk and providing tailored treatment."

—Michael Potts

Reference:

Fridman Y. Myocardial fibrosis is prevalent in obstructive sleep apnea and associated with hospitalization for heart failure or death [presented at EuroCMR 2016]. May 13, 2016, Florence, Italy.  

EuroCMR. Myocardial fibrosis identified as new therapeutic target [press release]. May 13, 2016. http://www.eurekalert.org/pub_releases/2016-05/esoc-mfi051116.php.