Reliability of intraoperative transesophageal echocardiography during tetralogy of Fallot repair

There is limited information available concerning the accuracy of intraoperative transesophageal echocardiography (TEE) in predicting the extent of residual abnormalities after recovery from surgical repair of tetralogy of Fallot. Therefore, we investigated differences between the results of final postbypass TEE and those of postrecovery (mean, 6 days after surgery) transthoracic echocardiography in a total of 28 consecutive pediatric patients who underwent repair of tetralogy of Fallot with biplane or multiplane TEE. Both postbypass and postrecovery echocardiographic examinations included measurements of the right ventricle (RV)-main pulmonary artery (PA) and the main PA-branch PA peak instantaneous gradients, the degree of pulmonary valvar insufficiency, and color Doppler interrogation of the ventricular septum for residual defects. The RV-main PA gradient did not change significantly: 15 ± 13 vs 18 ± 14 mmHg (postbypass versus postrecovery, mean ± SD). None of the patients had a decrease of ≥ 10 mmHg; and only one patient had an increase of ≥ 15 mmHg. There also was no change in the degree of pulmonary insufficiency (3.0 ± 1.2 versus 3.1 ± 1.1, using a scale of 0 to 4). Only one of the seven very small (≤ 2 mm) residual ventricular septal defects was not discovered during postbypass TEE. However, postrecovery transthoracic echocardiography detected significant branch PA stenosis (peak gradient, ≥ 15 mmHg) in five patients (18%) that was not detected during postbypass TEE (P < 0.03). Of the branch PA stenoses that were not detected during TEE, four were left and one was right. Conclusions: Postbypass TEE after tetralogy of Fallot repair reliably predicts residual postrecovery hemodynamic abnormalities, except for branch PA stenosis.