Left Main Stem Originating from the Right Coronary Sinus

A 55 year old woman presented herself to a cardiologist because of atypical chest pain. She had no cardiovascular risk factors. Her exercise test reveiled down sloping ST segment depression of 2 mm.

On coronary angiography, an anomalous origin of the left main stem from the right coronary sinus of Valsalvae was noted. The patient was referred for a myocardial perfusion test to exclude significant myocardial ischemia and for a navigator guided CMR of her coronary arteries in order to exclude a potentially dangerous course of the left main stem between the Aorta and the Pulmonary Trunc.

CMR was performed using navigator technique in a quiet breathing fashion in the supine position with image resolution of 1.5x1.5 mm and 20 slices. Figure 1 shows a slice at the proximal level of the right coronary artery, .Figure 2 shows a slice at the level of the elongated left main stem artery crossing anterior to the pulmonary trunc. Figure 3 shows a path tracking reconstruction of the RCA, the left main stem and the proximal and mid portion of the LAD. The course of the elongated left main stem is again clearly depicted and located anterior to the pulmonary trunc.

Figure 1