Single photon emission computed tomography dual isotope myocardial perfusion imaging in women with systemic lupus erythematosus. I. Prevalence and distribution of abnormalities.

OBJECTIVE: To determine the prevalence of myocardial perfusion abnormalities in women with systemic lupus erythematosus (SLE) using single photon emission computed tomography (SPECT) dual isotope myocardial perfusion imaging (DIMPI).

METHODS: Consecutive female patients registered at the University of Toronto Lupus Clinic were offered DIMPI evaluation and all who accepted were studied. Patients underwent SPECT DIMPI using dipyridamole stress. Resting and stress images were acquired using thallium-201 (201TI) and technetium 99m-sestamibi (99mTc sestamibi), respectively. We recorded segmental perfusion abnormalities, severity and reversibility of any abnormality, and number of vessel territories involved. Ejection fraction was also measured.

RESULTS: One hundred thirty patients were studied. Mean (SD) age and disease duration at study were 45.1 (11.1) years and 14.6 (9.4) years, respectively. Thirteen patients (10%) had a history of angina pectoris or myocardial infarction. Overall, 52 (40%) patients had an abnormality of myocardial perfusion, including 11 (85%) with a history of angina or myocardial infarction. In those with no history of coronary artery disease, 41 (35%) had an abnormality detected. The perfusion defect was reversible in 47 (90%). In 37 (71%) cases perfusion defects were seen in the region of a single vessel territory. Eighteen (13.8%) patients had an ejection fraction (EF) < 50%.

CONCLUSION: Using SPECT DIMPI, 40% of all women with SLE and 35% of women with SLE with no history of coronary artery disease had abnormalities of myocardial perfusion, suggesting a high prevalence of early coronary artery disease. The early detection of disease will facilitate study of atherosclerotic risk factors; such women can also be targeted for a focused program of risk factor management.