This Article Full Text Full Text (PDF) Submit a related Letter to the Editor Purchase Article View Shopping Cart Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Duvernoy, C. Articles by Mosca, L. Search for Related Content PubMed PubMed Citation Articles by Duvernoy, C. Articles by Mosca, L.

Myocardial Blood Flow and Flow Reserve in Response to Hormone Therapy in Postmenopausal Women with Risk Factors for Coronary Disease

Division of Cardiology (C.D., J.M., K.B.), University of Michigan, Ann Arbor, Michigan 48109; Cardiology Section (C.D., A.B.), Veterans Affairs Medical Center, Ann Arbor, Michigan 48105; Nuclear Medicine (O.M.), Wayne State University Positron Emission Tomography Center, Detroit, Michigan 48201; and Preventive Cardiology (L.M.), Columbia University, New York, New York 10032

Address all correspondence and requests for reprints to: Dr. Claire Duvernoy, Assistant Professor of Medicine, Division of Cardiology, University of Michigan, Veterans Affairs Medical Center, 2215 Fuller Road, Box 111A, Ann Arbor, Michigan 48105-2399. E-mail: duvernoy{at}umich.edu.

Estrogen has beneficial effects on markers of coronary heart disease (CHD) risk, but may increase overall CHD events. The effects of hormone therapy on vascular endothelial function have been mixed, and require further assessment. We studied the myocardial blood flow (MBF) response to postmenopausal combination hormone therapy (CHT) in postmenopausal women with risk factors for CHD.

We performed dynamic [¹³N]ammonia positron emission tomography in 15 postmenopausal women in a 7-month placebo-controlled crossover trial of continuous conjugated equine estrogen/cyclical micronized progesterone. MBF was measured at rest, after sympathetic stimulation with the cold pressor test (CPT), and after iv adenosine infusion, to determine baseline, endothelium-dependent, and maximal flows, respectively.

Response to CPT was neutral in all women at baseline (–0.51 ± 27%). Adenosine induced a marked increase in MBF (161 ± 111%). Treatment with 3 months of combined estrogen/progestin CHT did not change CPT or adenosine MBF responses. Myocardial flow reserve was unchanged as well.

In this group of postmenopausal women at higher cardiovascular risk, no association was found between CHT assignment and change in MBF. Further study is needed to clarify the effects of CHT on the endothelium of women with presumably diseased vasculature.

This work was supported by a grant from the Society for Women’s Health Research and Pfizer, Inc. Support for PET studies was also provided by the Veterans Affairs Ann Arbor Health Care System.

Abbreviations: CEE, Conjugated equine estrogen; CHD, coronary heart disease; CHT, combination HT; CPT, cold pressor test; HRT, hormone replacement therapy; HT, hormone therapy; MBF, myocardial blood flow; MFR, myocardial flow reserve; MP, micronized progesterone; MPA, medroxyprogesterone acetate; NO, nitric oxide; PET, positron emission tomography; RPP, rate-pressure product.