We report on three patients with kinking in the proximal aortic arch that developed after Lecompte modification of the arterial switch operation. Two patients had a previous subclavian patch repair of coarctation of the aorta and had an associated hypoplasia of the transverse aortic arch, and one patient had hemodynamically mild coarctation at the anatomical repair. A severe pressure gradient across the kinked area ("neo-coarctation") necessitating reoperation developed in one patient. The acute arch angulation appears to be due to an excessive posterior displacement of the ascending aorta by the anterior relocation of either the right or left main pulmonary artery branch from underneath the aortic arch. A foreshortened and frequently hypoplastic transverse aortic arch, a common association with coarctation of the aorta, appears to be especially vulnerable to the development of "neo-coarctation" after the Lecompte modification of the anatomical repair of transposed great arteries.