SMALL LEFT CORONARY-ARTERIES AFTER ARTERIAL SWITCH OPERATION FOR COMPLETE TRANSPOSITION

Background. Myocardial perfusion is not completely normal and ventricu lar function is depressed in some patients after the arterial switch o peration. The basic mechanism has not yet been defined totally. Method s. The diameters of the right left main trunk, anterior descending, an d circumflex corollary arteries were measured by computer-assisted den sitometry at 8 to 86 months (mean, 47.5 months) after the arterial swi tch operation in 86 patients. Results. The Z scores, compared with con trol, were +2.0 +/- 0.3, -1.8 +/- 0.3, and -1.5 +/- 0.3 for the right, left anterior descending, and circumflex coronary arteries, respectiv ely. The Z score for the total cross-sectional area of the three vesse ls was -1.5 +/- 0.3. These parameters did not correlate with left vent ricular ejection fraction. Conclusions. At the midterm follow-up after the arterial switch operation for complete transposition of the great arteries, the left coronary arteries are small. ih careful follow-up study is mandatory tea clarify the clinical significance of this findi ng. (C) 1997 by The Society of Thoracic Surgeons.