Background: To assess the acute effect of a single dose of 10 mg oral micronized 17beta-estradiol on microcirculation in postmenopausal women with and without coronary artery disease and its potential influence on exercise capacity.
Methods: Postmenopausal women (n=11) with coronary artery disease had symptoms of ischemic heart disease and at least 1 mm ST depression at exercise. Microcirculation was examined by vital microscopy, with and without the acute administration of estrogen in a placebo-controlled cross-over design. Exercise test was performed on bicycle. The microcirculatory findings were contrasted to those in 14 healthy postmenopausal women.
Results: 17Beta-estradiol in serum and blood flow velocity increased significantly after acute oral estrogen administration both in women with coronary artery disease (p<0.001) and in healthy women (p<0.0001), with no significant difference between the two groups. No effect on exercise capacity or ST depression at exercise was detected.
Conclusions: Previously reported data that a single dose of estrogen administered to postmenopausal women results in positive effects on exercise was not reproduced. An increased peripheral microvascular flow velocity was detected in women with coronary artery disease and this increase was not accompanied by an increased exercise capacity.