Congenital Absence of the Left Circumflex Artery With Super-Dominant Right Coronary Artery: Extremely Rare Coronary Anomaly

Abstract

Among the congenital anomalies of the coronary arteries, absent left circumflex artery (LCX) defect is extremely rare. Only a few cases have been reported in the literature. We report a case of a 48-year-old female who presented with a 4-month history of exertional chest pain with positive stress (treadmill) test. Conventional coronary angiogram showed a normal left anterior descending, absent LCX and a super-dominant right coronary artery (RCA) with prominent branches. Aortography also failed to show a separate ostium for the left circumflex artery. Multi-detector computed tomographic coronary angiography was performed to confirm the diagnosis of congenital absence of the LCX. It is a benign incidental finding, however some patients present with angina-like symptoms often resulting in detection of this rare anatomy on coronary angiography. Precise morphological and functional evaluation of the anomalous coronary artery is important for selecting the best treatment modality and better prognosis.

Congenital absence of the left circumflex artery: Case series and review

“…In those cases who had myocardial infarction secondary to acute thrombotic occlusion of the superdominant RCA, results in a large infarction of the inferior, posterior and lateral walls, which were stated to be similar to two-vessel disease involving both RCA and LCX simultaneously. 17,40,52 In all CALCx cases, STEMI was by far the most common clinical manifestation as an acute coronary syndrome and the second most prevalent clinical diagnosis in our case series.…”

ST-Elevation Myocardial Infarction in a Patient with Anomalous Left Anterior Descending Artery and Absent Left Circumflex

“…The previously published reports described patients who underwent angiography for exertional chest discomfort and were found to have either high-grade stenosis in a dominant RCA [3] or no significant coronary stenosis [4]. We have also found few reports of congenitally absent LCX and super-dominant RCA but with normal LAD origin which might carry similar clinical significance and further emphasize on the importance of precise morphological and functional evaluation of the CAA in selecting the best treatment modality and better prognosis [5-8].…”

Independent origin of anterior interventricular and left marginal arteries from the left posterior aortic sinus

“…Its possible variations have been well documented. In rare cases, it could be absent congenitally, in which case, the right coronary artery is super dominant [1]. A recent study from Thailand by Kultida et al (2018) [4] has reported the absence of the left main coronary artery and left circumflex artery in 0.4% cases.…”

“…Coronary arteries are the branches of ascending aorta and they supply the myocardium of the heart. Some of the variations like, absence of one of the coronary arteries [1], origin from pulmonary trunk [2], and origin of both coronary arteries as a common trunk [3] have been reported in the literature. The anatomical variations may or may not affect the normal functioning of the heart.…”