Adverse cardiovascular outcomes in women with nonobstructive coronary artery disease: a report from the Women's Ischemia Syndrome Evaluation Study and the St James Women Take Heart Project

Abstract

Background: Women with clinical findings suggestive of ischemia but without findings of obstructive coronary artery disease (CAD) on angiography represent a frequent clinical problem; predicting prognosis is challenging.

Methods: The Women's Ischemia Syndrome Evaluation (WISE) study examined symptomatic women referred for clinically indicated coronary angiography and followed up for a mean 5.2 years. The St James Women Take Heart (WTH) Project enrolled asymptomatic, community-based women with no history of heart disease who were followed up for 10 years. We compared cardiovascular events (ie, myocardial infarction, stroke, and hospitalization for heart failure) and death in 540 WISE women with suspected ischemia but no angiographic evidence of obstructive CAD with those from a cohort of 1000 age- and race-matched WTH women.

Results: Compared with the WISE women, asymptomatic WTH women had a lower prevalence of obesity, family history of CAD, hypertension, and diabetes mellitus (P < .001). Five-year annualized event rates for cardiovascular events were 16.0% in WISE women with nonobstructive CAD (stenosis in any coronary artery of 1%-49%), 7.9% in WISE women with normal coronary arteries (stenosis of 0% in all coronary arteries), and 2.4% in asymptomatic WTH women (P < or = .002), after adjusting for baseline CAD risk factors. The cardiovascular events were most frequent in women with 4 or more cardiac risk factors, with the 5-year annualized cardiovascular event rate being 25.3% in women with nonobstructive CAD, 13.9% in WISE women with normal coronary arteries, and 6.5% in asymptomatic women (P = .003).

Conclusion: Women with symptoms and signs suggestive of ischemia but without obstructive CAD are at elevated risk for cardiovascular events compared with asymptomatic community-based women.

Figure 1

Five-year primary composite event rate according to risk factor category. Rates are presented for asymptomatic women (group 1) compared with symptomatic women with normal coronary arteries (0% stenosis) (group 2) and nonobstructive coronary artery disease (stenosis in any coronary artery of 1%–49%) (group 3). Cardiovascular risk factors include smoking, diabetes mellitus, low-density lipoprotein cholesterol level of greater than 130 mg/dL, high-density lipoprotein cholesterol level of less than 50 mg/dL, family history of coronary artery disease, body mass index (calculated as weight in kilograms divided by height in meters squared) of 30 or more, and systolic blood pressure higher than 140 mm Hg. Primary composite event consists of nonfatal myocardial infarction, hospitalization for congestive heart failure, stroke, or cardiovascular death. WISE indicates Women’s Ischemia Syndrome Evaluation; WTH, St James Women Take Heart Project. To convert cholesterol levels to millimoles per liter, multiply by 0.0259.

Figure 2

Five-year primary composite event rate according to age. Rates are presented for asymptomatic women (group 1) compared with symptomatic women with normal coronary arteries (0% stenosis) (group 2) and nonobstructive coronary artery disease (stenosis in any coronary artery of 1%–49%) (group 3). Primary composite event rate consists of nonfatal myocardial infarction, hospitalization for congestive heart failure, stroke, or cardiovascular death. WISE indicates Women’s Ischemia Syndrome Evaluation; WTH, St James Women Take Heart Project.

Figure 3

Suggested algorithm for the treatment of women with and without symptoms suggestive of ischemia. AHA indicates American Hospital Association; CAD, coronary artery disease; MRI, magnetic resonance imaging; PET, positron emission tomography; and SPECT, single-photon emission computed tomography. Adapted and modified with permission from Bugiardini and Bairey Merz.