[Cardiac performance before and after Jatene procedure for transposition of the great arteries: with specific reference to post-operative supravalvular pulmonary stenosis].

The cardiac performance was evaluated in patients who had received arterial switch operation (AS-op) for transposition of the great arteries (TGA) in their infancy with special attention to postoperative supravalvular pulmonary stenosis (SVPS). AS-op was performed in 36 infants; 13 with simple TGA and 23 with TGA accompanied with ventricular septal defect. Nine patients had undergone pulmonary arterial banding with systemico-pulmonary shunt. The mean age at surgery was 7 months. Postoperative catheterization was performed on average of 15 months after surgery. The end-diastolic volume (EDV) and ejection fraction (EF) of the left and right ventricles (LV, RV) were calculated from biplane cineangiograms. LVEDV and RVEDV were normalized and expressed as % of normals. SVPS was defined as peak systolic pressure gradient of 50 mmHg or higher between the RV and the pulmonary artery (PA). The mean LVEDV, RVEDV, LVEF and RVEF values were all within the normal range. Inverse correlation was observed between the peak systolic RV-PA pressure gradient and RVEF (n = 29, r = -0.84, p less than 0.001). SVPS after AS-op was observed in 8 patients (22%). Stenosis was observed at the site of anastomosis of the artery. In these cases, the diameter of the PA at the stenotic site decreased to 52% of the preoperative values. Branch stenosis of the PA was observed in 3 patients who had undergone surgery during the neonatal period. Generally, the results after AS-op were satisfactory in terms of cardiac performance. Postoperative SVPS was observed in 8 patients (22%) with decreased RVEF. Careful observations of the growth of PA after AS-op are mandatory.