• Images in cardiology

A 64 year old woman with chest pain and ECG consistent with an inferior myocardial infarction received thrombolysis. There was no evidence of reperfusion and she underwent rescue angioplasty. She was found to have a single coronary artery arising from the right sinus of Valsalva. The right coronary artery (RCA) was occluded by thrombus (panel A). During the first contrast injection a portion of the thrombus was dislodged and travelled across the left main stem (panel B) into the left anterior descending artery (LAD) causing a distal occlusion (panel C). The proximal occlusion of the RCA was successfully treated by thrombectomy (X-sizer, Plymouth, Minnesota, USA) and stenting (Sonic, Velocity 4.0 × 28 mm) with an excellent final angiographic result (panel D), although unfortunately there remained sluggish blood flow in the LAD. The patient required an intra-aortic balloon pump and inotropic support for 24 hours. The peak creatine kinase concentration was 5500 u/l.

Single coronary arteries are a recognised but rare anomaly with an incidence of around 0.02%. They may be clinically significant when a major branch passes between the aorta and the right ventricular outflow tract as was found in this case. This particular anomaly is associated with sudden cardiac death possibly due to compression between the major vessels. In our middle aged patient it is likely that the thrombus in the proximal RCA was a consequence of underlying atherosclerosis. Unfortunately occlusion of the distal LAD resulted from embolised thrombus dislodged from the RCA by contrast injection—an extremely rare event.