Malignant Right Coronary Artery Anomaly Detected by Magnetic Resonance Coronary Angiography
A 66-year-old man presented with typical angina pectoris. The angina was exercise related and had developed in the past few weeks. Treadmill exercise testing induced the angina but did not reveal signs of ischemia on the ECG. Technetium myocardial perfusion scintigraphy showed a minor perfusion defect in the inferoposterior wall (Figure 1). Coronary catheterization showed the left main, left anterior descending, and left circumflex arteries without clinically significant stenoses. The origin of the right coronary artery (RCA), however, could not be engaged, preventing selective visualization. Distally, the RCA showed retrograde filling. A second catheterization effort failed for the same reason.
The patient was diagnosed with a total occlusion of the RCA and/or possible right coronary anomaly. He was referred to our university hospital, in which, according to protocol, suspected coronary anomalies are evaluated using magnetic resonance (MR) coronary angiography before an eventual cardiac catheterization. A state-of-the-art MR technique without exogenous contrast was used.
The MR acquisition revealed an anomalous RCA originating from the left coronary sinus and coursing between the aortic root and main pulmonary artery, providing a rare example of a classic malignant RCA anomaly. Additionally, the suspicion of a stenotic lesion in the proximal RCA was raised (Figure 2). A 3-dimensional reconstruction was made to illustrate the anatomic perspective (Figure 3).
On the basis of the MR findings and symptoms, the patient was scheduled for coronary artery bypass graft surgery. The MR findings prevented the need for a third catheterization procedure because the diagnosis and preferred treatment were now clear. During surgery, the anomalous origin of the RCA and the stenotic lesion as seen on the MR acquisitions were confirmed. The patient received a bypass graft to the right descending posterior artery and recovered uneventfully.
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 the Circulation Editorial Office, St Luke’s Episcopal Hospital/Texas Heart Institute, 6720 Bertner Ave, MC1-267, Houston, TX 77030.