SURGICAL MANAGEMENT OF RIGHT VENTRICULAR OURFLOW TRACT AFTER TOTAL CORRECTION OF TETRALOGY OF FALLOT

Abstract

Radical surgery was performed in 44 patients with tetralogy of Fallot between April 1980 and December 1983. Three patients (6.8%) died in the early stage. Materials and techniques used for the reconstruction of the right ventricular outflow tract were investigated in 40 patients in whom hemodynamics could be determined. The 40 patients ranged in age from 4 to 56 at the time of surgery, with a mean age of 11 and a male/female ratio of 22:18. For surgery, in all patients, atonic cardiac arrest was induced during the use of Young's solution, and cardiac muscles were protected and maintained at about 15°C. Excision of abnormal muscle bundles at the right ventricular outflow tract was performed in all patients, followed by patch closure of interventricular septal defect and right ventricular outflow tract reconstruction. The techniques of this reconstruction were formation of the pulmonary valve in three patients (Group I, mean age 24), right ventricular patch reconstruction using EPTFE in four (Group II, mean age 31), right ventricular and pulmonary arterial reconstruction using a glutaraldehyde-treated single-valve-containing porcine pericardial patch (Rygg) in five (Group III, mean age 27), and right ventricular and pulmonary arterial reconstruction by a combined patch of single-valve containing autologous pericardium and EPTFE in 28 (Group IV, mean age 7). Development in Group I was better than in other groups, with the ratio of the diameter of the main pulmonary artery to that of the ascending aorta being 0.67±0.31. A relative right ventricular-pulmonary artery pressure difference remained in Group III as compared with the other groups. This was because patients in Group III were adults after shunt surgery, in whom stenosis of the right ventricular outflow tract advanced and the right intraventricular narrowing was not fully improved even by minimal cardiac muscle resection and patch enlargement. In Group IV, the pulmonary arterial diastolic pressure (13.8±0.8mmHg) was comparatively well maintained, showing a tendency of mild pulmonary insufficiency. Enlargement of the right ventricular outflow tract by using a combined patch of single-valve-containing autologous pericardium and EPTFE is said to be unsatisfactory in long-term prognosis. However, our cases showed stable results, and this method is therefore considered to be an almost perfect procedure for right ventricular outflow tract reconstruction.