[Temporary use of left ventricle-to-pulmonary artery extracardiac conduit for the surgical repair of complete transposition of the great arteries with ventricular septal defect and left ventricular outflow tract obstruction].

Abstract

A 1.8-year-old boy was first admitted to our hospital at 12 days of age with the diagnosis of transposition of the great arteries (TGA), ventricular septal defect (VSD), and left ventricular outflow tract obstruction (LVOTO). Echocardiography and catheter examination at 10 months of age disclosed severe organic stenosis of left ventricular outflow tract (LVOT) with its diameter of 5.6 mm (50% of N) and the left to right ventricular (LV/RV) pressure ratio of 0.6. At 1.8 years of age, he underwent complete correction which comprised intraatrial switch (Senning procedure), direct closure of VSD, and removal of thickened endocardium at LVOT. Because of the residual LVOTO, evidenced by postoperative LV/RV pressure ratio of 1.4, placement of 14 mm PTFE graft extracardiac conduit was concomitantly performed. The conduit from the left ventricular apex to the main pulmonary artery effectively lowered the left ventricular pressure with LV/RV pressure ratio of 0.68. Repeat catheter examination at 2.10 years of age revealed further descent of LV/RV pressure ratio to 0.32. Based on the findings that balloon occlusion of the conduit elicited only a minimal elevation of the left ventricular pressure (from 30 to 34 mmHg), the conduit was removed at 3.6 years of age. The third catheter examination at the age of 3.9 years confirmed LV/RV pressure ratio of 0.43. The patient is leading a normal life. without medication 3 years after the operation. This experience draws us to conclude that placement of left ventricle-to-pulmonary artery conduit concomitantly with the intraatrial switch is a useful adjunctive procedure for the complete correction of TGA, small VSD, and LVOTO, and that, in a subset of the patients, this procedure may allow amelioration of LVOTO and secondary removal of the conduit.