Congenital coronary anomalies are uncommon.4
Ectopic origin of a coronary artery from the conteralateral sinus of valsalva may have important clinical manifestation, most notably exertional sudden cardiac death particulary in youth.5
A single coronary artery arising from the right sinus of valsalva has four anatomical courses;4
1- Anterior course: main stem turns anterior in front of RVOT.
2- Interarterial course: main stem turn between great vessels,aorta and pulmonary artery.
3- Septal course, main stem had interamyocardial septal continuation.4-Posterior, main stem turn posteriorly behind the aorta.
The interarterial course has been known to have the worst prognosis with respect to symptoms and incidence of sudden cardiac death (SCD).8
Other types can also present with myocardial ischemia, heart failure or sudden cardiac death.
In the interarterial course, ischemia or SCD are assumed to be caused by vascular compression or kinking.9
Since the overall number of these patients is small, the treatment strategy varies and is not clearly defined.The possible treatment of choice to prevent SCD in particular interarterial course is CABG using the internal mammary artery as a conduit.10
In this case we report a rare occurance of simultaneous occurence of mitral stenosis with ectopic origin of left main stem coronary artery from right sinus of Valsalva.