Abnormalities of the tricuspid valve in complete transposition of the great arteries with ventricular septal defect.

Structural abnormalities of the tricuspid valve were encountered in 38 of 121 autopsy specimens of complete transposition of the great arteries (TGA) with ventricular septal defect (VSD) (31%). Forty abnormalities were identified, including severe straddling of the tricuspid valve tensor apparatus in two, valvular dysplasia in two, left ventricular outflow tract obstruction caused by accessory tricuspid valvular tissue in two, double orifice in one, and abnormal chordal insertions in 33. Seventeen (14%) had abnormalities which were judged to have importance in the surgical management: in two cases, a straddling tricuspid valve would have prevented VSD closure; both cases with valve dysplasia would have required anuloplasty or valve replacement; one with left ventricular outflow obstruction from accessory tricuspid tissue would have required closure of a small VSD; and 12 had abnormal chordal insertions which were surgically significant. Of these 12 who were otherwise candidates for a Rastelli repair, this approach would have been possible in two only by enlargement of the VSD and deviation of the patch. In the 10 others abnormal chordal insertions to the superior aspect of the VSD would have prohibited a Rastelli operation. Abnormal tricuspid valve chordae of this type were present in 9 of 25 (36%) cases with overriding of the pulmonary trunk. Tricuspid valvular abnormalities may significantly alter the surgical approach to patients with complete transposition of the great arteries with VSD.