Stress-Rest Myocardial Perfusion SPECT for Functional Assessment of Coronary Arteries with Anomalous Origin or Course

Anomalous coronary arteries (ACAs) may be clinically silent and totally benign or associated with catastrophic and fatal presentations. It has been postulated that the proximal course of an ACA is a decisive factor in risk stratification and surgical approach. Particularly, a course between the aorta and pulmonary trunk carries a high risk of major adverse events. We sought to evaluate the anatomic course of documented ACAs by transesophageal echocardiography (TEE) and to study their functional importance using stress-rest (99m)Tc-sestamibi ((99m)Tc-MIBI) myocardial perfusion SPECT. From a cohort of patients undergoing coronary angiography in our department between January 1997 and April 2003, we selected 14 with ACAs but without CAD (9 men and 5 women; mean age, 50.7 +/- 14.6 y). All patients underwent TEE and stress-rest (99m)Tc-MIBI myocardial perfusion SPECT. TEE correctly identified the origin of all ACAs and revealed an anomalous course between the great vessels in 5 patients. At exercise myocardial perfusion SPECT, 4 of 14 patients demonstrated a reversible myocardial perfusion defect. All these patients had an anomalous course between the aorta and pulmonary artery. In this study, 4 of 5 (80%) anomalous courses between the aorta and pulmonary artery were associated with the finding of a reversible perfusion defect on stress-rest SPECT. An integrated evaluation of anatomic course and hemodynamic importance could be useful in the management of ACA.