(HealthDay)—For patients with pulmonary hypertension associated with heart failure and preserved ejection fraction (PH-HFpEF), the six-minute walk distance (6-MWD) test can independently predict outcome, according to a study published in the June issue of JACC: Heart Failure.

Caroline Zotter-Tufaro, from the Medical University of Vienna, and colleagues examined the prognostic significance and clinical determinants of the 6-MWD. Data were included for 142 patients with PH-HFpEF, as confirmed by right heart catheter.

The researchers found that 30.3 percent of patients reached the combined end point of hospitalization for and/or death for cardiac reasons after a mean follow-up of 14.0 months. The 6-MWD independently predicted outcome and was affected by clinical, echocardiographic, hemodynamic, laboratory, and pulmonary parameters. The 6-MWD and the extent of extracellular matrix in the left ventricular myocardium were significantly inversely correlated.

"Impaired exercise capacity in PH-HFpEF patients is explained by cardiac and noncardiac factors," the authors write. "The 6-MWD predicts outcome and may be a useful end point in clinical trials."