[The single coronary artery. 2 clinical cases].

Single coronary artery is a rare congenital abnormality, characterized by a common origin of both right and left coronary arteries from a single aortic ostium. Recognizing the anatomic relationship between the single coronary artery and the great vessels is of prognostic importance: the variant in which the first part of the coronary artery passes between the aorta and the pulmonary trunk has the worst prognosis, and may be associated with sudden death during exercise. We describe 2 cases of single coronary artery: the first is of the more unusual left type, in which a Swan-Ganz catheter in the pulmonary artery helped to recognize the interarterial course subtype. The second case is a right type, belonging to the "septal" subtype, in which the left main trunk has a partial intramyocardial course: this variant has a good prognosis and can be distinguished from the "interarterial" subtype by the presence of a septal branch originating from the left main trunk.