Catheter evaluation of left ventricular shape and function 1 or more years after anatomic correction of transposition of the great arteries.

Twenty-eight children were reinvestigated by cardiac catheterization and angiography greater than 1 year after anatomic correction of transposition of the great arteries (TGA). Seventeen patients with simple TGA underwent banding of the pulmonary trunk plus or minus systemic to pulmonary artery shunt to prepare the left ventricle for anatomic correction. In addition to TGA, 10 of the remaining 11 patients had a large ventricular septal defect and 1 had an aorticopulmonary window. They required no preparation of the left ventricle. Age at repair ranged from 2 to 120 months (mean 26). Catheterization 12 to 48 months after anatomic repair revealed a left ventricular end-diastolic pressure of 4 to 14 mm Hg (mean 9.5 +/- 2.5 [+/- standard deviation]). Ejection fraction ranged from 52 to 75% (mean 66 +/- 8). Frame-by-frame computer-assisted analysis of left ventricular (LV) contraction and relaxation was performed in 14 patients and compared with normal left ventriculograms. Shape index, derived as 4 pi X cavity area/perimeter2 X 100, was measured in 24 patients and showed a mean index of 89 +/- 3% at end-diastole and 79 +/- 8% at end-systole. A control group had a mean diastolic index of 86 +/- 6% and mean systolic index of 73 +/- 8%. It is concluded that LV shape after anatomic correction tends to be more globular than normal and changes little during systole. LV ejection fraction and end-diastolic pressure are normal.