Self-reported physical activity and myocardial flow reserve in postmenopausal women at risk for cardiovascular disease.

BACKGROUND Regular exercise protects against coronary heart disease (CHD) events and improves vascular reactivity. Exercise effects on myocardial flow reserve (MFR) are not well studied. METHODS We performed dynamic N-13 ammonia positron emission tomography (PET) in 16 postmenopausal women (60 +/- 6 years) to measure myocardial blood flow (MBF) and MFR. We also obtained information from each woman on her self-reported physical activity. RESULTS Of the 16 patients, 6 reported moderate regular physical activity, and 10 did not. Women who reported regular, at least moderate physical activity had a higher percentage increase in adenosine MBF from rest compared with women who did not exercise (268% vs. 129%, p = 0.04) and had a significantly higher mean maximal MFR (3.68 vs. 2.29, p = 0.04). CONCLUSIONS These findings provide further mechanistic support for the beneficial cardiovascular effects of exercise.