Abstract
73 year-old man presented to our emergency department with complaint of retrosternal chest pain since 2 day and admitted with diagnosis of unstable angina. He underwent diagnostic coronary angiography in which left circumflex artery (LCX) was not visualized during injection of the left coronary artery; indeed, it was originated, with common origin with RCA, from right coronary sinus of Valsalva. This case report is one of the uncommon cases with aberrant coronary arteries who presented with unstable angina. Moreover, coronary angiography with following coronary angioplasty was performed for him in a challenging course and angle for coronary intervention.