Introduction: The coronary anatomic variation of the left circumflex artery (LCx) is considered as the most common anatomic variation with a separate ostium from the right sinus, and very unusual variation as a proximal branch of right coronary artery (RCA). Case report: We report two cases, the first case is a 64-year-old man with chest pain and with history of hypertension, obesity, dyslipidemia and current smoker, and the second case is a 67-year-old who presented to the emergency department with chest pain and with a past medical history of arterial hypertension and type 2 diabetes mellitus. In the coronarography of the first case is detected an ectopic left circumflex coronary artery from the right coronary sinus with stenotic changes in RCA and LCx. The second case in the coronary angiography revealed an ectopic left circumflex coronary artery from the proximal part of the right coronary artery with stenotic changes in LAD, RCA and LCx. Based on guidelines for revascularization our patients successfully underwent treatment procedures. We present two cases that because of the atherosclerotic coronary artery disease leads to the need of coronarography find out the presence of coronary artery anomalies. Conclusion: During the coronarography we should think about coronary artery anomaly or missing artery knowing that type of these anomalies, considering that may be a contributing factor in the development of the atherosclerosis determines the method of the treatment.
left circumflex artery, anomalous origin.