NEW YORK (Reuters Health) – Even in the absence of ischemic heart disease, exercise capacity is limited in people with abnormal left ventricular diastolic function, investigators report in the Journal of the American Medical Association for January 21.

“Although these data require confirmation in prospective studies, they point to a potential modifiable factor that might be a target for interventions that could maintain exercise capacity with aging,” writes the research team from the Mayo Clinic in Rochester, Minnesota.

Principal investigator Dr. Patricia A. Pellikka and her colleagues studied 2867 patients who underwent clinically indicated exercise echocardiography in 2006. Patients with significant valvular heart disease, ejection fractions of less than 50%, or with exercise-induced myocardial ischemia were excluded.

Two-dimensional and Doppler techniques were used to assess left ventricular systolic and diastolic function.

Diastolic function was found to be normal in 1784 subjects, mildly abnormal in 785, and moderately/severely abnormal in 298. Mean age in the three groups was 53, 67, and 66 years, respectively.

In multivariate analysis, the authors report, “resting diastolic function (was) the strongest echocardiographic correlate of exercise tolerance… superseded only by the clinical factors of advancing age, female sex, and increasing body mass index.”

The association between diastolic dysfunction and exercise capacity remained significant after adjusting for resting heart rate, blood pressure, medication use, comorbidities, and other echocardiographic parameters.

Dr. Pellikka’s group points out that exercise training and pharmacologic therapy, particularly angiotensin II blockade, may improve diastolic function.

“Although data with respect to modifying diastolic function are unclear and merit further study,” the researchers advise, “current approaches should include aggressive treatment of risk factors such as hypertension and coronary artery disease to prevent development of diastolic abnormalities and related exercise limitations.”

Reference:
JAMA 2009;301:286-294.