Clinical Implications of Congenital Absence of Circumflex Coronary Artery

Coronary artery anomalies are rare clinical entities reported in 0.6% to 5.6% of diagnostic coronary angiographies. Anomalous origins of coronary arteries from distal segments are rarely reported. Presented herein is a coronary anomaly in which the circumflex artery (CX) originated as a continuation of the posterolateral branch of the right coronary artery (RCA) with separate left anterior descending (LAD) artery origination from the left sinus of Valsalva. The clinical presentation of such a rare anomaly is discussed, and the current literature regarding the congenital absence of CX is reviewed.
A 66-year-old male presented with angina pectoris. Coronary angiography revealed critical stenosis in the mid segment of the LAD artery and an anomalous origin of CX artery from the distal RCA. The CX was coursing as a continuation of the posterolateral branch of the RCA. Coronary angioplasty and stent deployment was performed for the LAD lesion, and the patient was discharged with medical therapy. The patient did not report recurrent anginal symptoms under medical therapy.
The congenital absence of the circumflex coronary artery is a rare coronary anomaly. The clinical presentation may vary, though most cases are asymptomatic during diagnosis. Such cases require close clinical follow-up since they entertain a future risk for being symptomatic, especially in the setting of atherosclerotic disease.