Congenital anomalous anatomy and course of coronary arteries are common
however atresia of LMS is extremely a rare condition. Fewer than 50
cases of congenital atresia of left main stem coronary artery have been
reported in the literature. The ostium or trunk of the left coronary
artery is atretic, and the left coronary artery and its branches are
supplied by the right coronary artery via coronary collaterals in a
retrograde direction. The pattern of presentation varies depending on
the age and anatomy of the patient. According to the literature these
cases present at a very early age with signs of heart failure whereas
adults may present with angina or shortness of breath. Its clinical
signs and symptoms often resemble anomalous origin of the left coronary
artery from the pulmonary artery and endomyocardial fibrosis. In
literature there are only five adult cases reported with congenital
atresia of LMS and an interesting fact is that one out of those five
cases was diagnosed on autopsy to have atresia of LMS. That patient was
a female at age of 76 years who died of reasons other than heart
symptoms. Therefore it may be inferred that the range of symptoms vary
from being completely asymptomatic to overt heart failure.