[Single right coronary artery with absence of the left coronary ostium].

We report the rare congenital anomaly of a singular right coronary artery in absence of the left coronary ostium. In a 31-years-old man, coronary arterial angiography demonstrated a right coronary artery which, arising from the right Sinus Valsalvae, first described the normal right coronary arterial course but in the apical region continued to follow, in reverse direction, the normal course of the left anterior descending artery. The proximal diameter of the vessel measured 5.2 mm. Thallium scintigraphy showed no ischemia of the anterior wall. The risk of developing circumscribed atherosclerosis due to anatomical reasons seems not to be increased, as no additional bifurcation nor kinking was to be found.