Anomalous origin of the right coronary artery from the contralateral aortic sinus is a rare but potentially fatal congenital abnormality. We analyzed 8.066 consecutive coronary angiograms and found 4 cases demonstrating this anomaly. In 2 cases the right coronary artery was without significant atherosclerotic lesions and coursed between the aorta and pulmonary trunk. In the 2 other cases the right coronary artery was significantly stenosed. In the last case, diagnosis was based on angiographic and dual-source computed tomographic examinations. Dual-source computed tomography showed precisely the origin and course of the right coronary artery between the ascending aorta and pulmonary artery. Moreover, stenoses of the anomalous coronary artery were depicted. Subsequent coronary interventions required modification of the Amplatz left guiding catheter, which enabled a sufficient support even for coronary artery stenting. Both methods seem to be complementary in the diagnostic and therapeutic process of this coronary anomaly.