Myocardial Ischemia and Occult Coronary Artery Disease
A57-year-old postmenopausal woman was admitted to the hospital because of worsening angina pectoris. A diagnosis of syndrome X had been made 3 years earlier on the grounds of chest pain, positive exercise stress test, and angiographically normal coronary arteries. Angina persisted despite use of diltiazem, nitrates, simvastatin, and imipramine. Risk factors included hypertension, overweight, and hypercholesterolemia.
At treadmill testing, chest pain and 2-mm ST-segment depression developed after 5 minutes of exercise, and sestamibi myocardial tomoscintigraphy showed a reversible tracer uptake defect in the anterior region (Figure⇓, panel A, arrows). Repeat coronary angiography did not show any “significant” stenosis (the left coronary artery is shown in panel B). However, intracoronary Doppler flow measurements at rest and after adenosine (panel C, top and bottom, respectively) showed a reduced maximal hyperemic flow velocity in the left anterior descending coronary artery (LAD) (LAD flow reserve, 2.4; left circumflex coronary artery flow reserve, 3.3). Intracoronary ultrasound imaging revealed an occult atherosclerotic plaque of the proximal LAD occupying 45% of the vessel area, with vessel remodeling (panel D: proximal LAD intravascular image is shown on the left and distal LAD on the right. pa indicates plaque area; diag, diagonal branch).
The woman refused hormone-replacement therapy. A recommendation for more effective dietary modification and weight management was reinforced, and atenolol was added to the therapy. After 6 months, there was no improvement in symptoms, and overweight persisted.
The editor of Images in Cardiovascular Medicine is Hugh A. McAllister, Jr, MD, Chief, Department of Pathology, St Luke’s Episcopal Hospital and Texas Heart Institute, and Clinical Professor of Pathology, University of Texas Medical School and Baylor College of Medicine.
Circulation encourages readers to submit cardiovascular images to Dr Hugh A. McAllister, Jr, St Luke’s Episcopal Hospital and Texas Heart Institute, 6720 Bertner Ave, MC1-267, Houston, TX 77030.
- Copyright © 1999 by American Heart Association