Estrogen Therapy After Coronary Bypass Surgery

ABSTRACT & COMMENTARY

Synopsis: Estrogen therapy improves survival after coronary bypass surgery.

Source: Sullivan JM, et al. Am J Cardiol 1997;79: 847-850.

Sullivan and colleagues from the university of Tennessee compared survival after coronary bypass surgery in women receiving estrogen therapy and women not receiving estrogen therapy. The 10-year survival rate in the estrogen users was 81.4% compared to 65.1% in the non-users. In addition, the women who were not on estrogen therapy had more severe coronary heart disease in the beginning. Sullivan et al conclude that the administration of estrogen following coronary bypass surgery significantly improves survival.

COMMENT BY LEON SPEROFF, MD

There is growing evidence that postmenopausal estrogen therapy can provide major protection against subsequent cardiovascular events in women who already have coronary heart disease. In this study, 92 women who used estrogen after surgery were compared to 861 who did not. Improved survival was noted at both the five-year mark as well as the 10-year mark in the estrogen users.

Table

Postmenopausal Hormone Clinical Trials

Primary Prevention

WHI (Women’s Health Initiative) n = 16,500

WISDOM (Women’s International Study

of Long Duration Oestrogen for Menopause) n = 34,000

Secondary Prevention

HERS (Heart & E/P Replacement Study) n = 2763

WEST (Western Connecticut Estrogen for

Prevention of Stroke Trial) n = 652

ESPRIT (Estrogen in the Prevention

of Reinfarction Trial) Angiographic Endpoint n = 2000

ERA (Estrogen Replacement &

Atherosclerosis Trial) n = 309

WELLHART (Women’s E/P Lipid Lowering

Heart Atherosclerosis Trial) n = 214

EAGAR (Estrogen & Bypass Graft

Atherosclerosis Regression Trial) n = 200

WAVE (Women’s Atherosclerosis

Vitamin/Estrogen Trial) n = 400

In a follow-up study of women after atherectomy, estrogen therapy was noted to inhibit the rate of restenosis (Am J Cardiol 1996;28:1111). In a study of women older than 65, ultrasonography of the carotid arteries documented reduced intimal thickness and stenosis in both estrogen and estrogen/progestin users (Am Epidemiol 1996;6:314). And, finally, a case-control study of 137 women on estrogen before and after coronary angioplasty found a reduced risk of subsequent heart attacks and strokes and better survival in the estrogen users (J Am Clinical Cardiol 1997;29:1). These studies all indicate that estrogen therapy not only inhibits the progression of coronary heart disease but may even produce regression of existing disease. Thus, the previous reluctance to provide estrogen to women with cardiovascular disease is rapidly disappearing. Cardiologists are quickly beginning to view estrogen as a first-line drug for these patients.

An important issue is what happens to these effects when progestational agents are added to therapy. Thus far, the news is good. Studies of actual clinical events in case-control and cohort studies are finding no evidence of attenuation of estrogen’s benefits on the cardiovascular system.

Currently, there are many randomized clinical trials underway dealing with primary prevention and secondary prevention of coronary heart disease. (See Table.)

It won’t be long before we have excellent, strong, and reliable data on these issues.

The following statements are true of estrogen therapy and coronary heart disease except:

a. postmenopausal estrogen therapy can both inhibit progression and cause regression of coronary heart disease.

b. estrogen/progestin therapy does not reduce the risk of coronary heart disease.

c. postmenopausal estrogen therapy after surgical procedures on the coronary arteries reduces the restenosis rate.

d. postmenopausal estrogen therapy after surgery on the coronary arteries reduces the risk of subsequent heart attacks.