Statistics from Altmetric.com
A 78 year old woman presented to hospital with chest pain and anterior T wave changes. She was started on clexane, intravenous (iv) nitrate, and iv tirofiban, and transferred for inpatient cardiac catheterisation. The proximal left anterior descending (LAD) coronary artery showed a subtotal lesion, however the right coronary artery (RCA) could not be cannulated by an experienced operator. The aortogram showed flow into a small atypical RCA, and the distal RCA was shown by collaterals from the LAD. In view of the development of a large groin haematoma and no recent chest pain, percutaneous coronary intervention to the LAD was deferred and a multislice computed tomography (MSCT) coronary angiogram was arranged to exclude an ostial RCA lesion.
MSCT coronary angiogram (Sensation 16, Siemens, Germany) was performed using an ECG gated standard protocol. An atypical RCA was demonstrated originating from the left sinus of Valsalva. It was small in overall diameter (1.2 mm) and passed between the aorta and pulmonary artery before following a standard course in the right atrioventricular groove. The atypical origin and initial course is shown (black arrows) in the left hand panel by a superiorly applied clip plane to a three dimensional volume reconstruction; it also shown in the right hand panel in an anterolateral three dimensional volume reconstruction with the obscuring pulmonary artery edited along with parts of the proximal LAD.
In this case, the aortogram suggested a posterior origin of the RCA. However, MSCT shows the atypical origin, with initial compression, followed by an increase in calibre of the aberrant vessel.