Objectives: To investigate prospectively the prediction of the neopulmonary stenosis (neo-PS) after arterial switch operation (ASO) for transposition of the great artery (TGA) with intraoperative transesophageal echocardiography (TEE). Methods: Infants with TGA undergoing the ASO were prospectively studied over 5 years. The neo-PS was defined when the peak flow velocity was over 3 m/s at the neo main pulmonary artery (neo-MPA) after ASO by TEE (TEEPS). Catheterization was performed if estimated peak neo-PS pressure gradient was over 40 mm Hg by transthoracic echocardiography. Balloon angioplasty was tried first and surgical reoperation was reserved for those with failed angioplasty. Results: In total 49 consecutive patients were enrolled into the cohort study. TEEPS was identified in 21 patients. For patients with TEEPS, freedom from reintervention was 28% at 1 year and 23% at 2 years. For patients without TEEPS, freedom from reintervention for PS was 92% at 1 year and 78% at 2 years. The time interval from ASO to reintervention was significantly shorter in patients with TEEPS than without TEEPS. Existence of TEEPS and non-Lecompte method were main risk factor for reintervention. Conclusion: The present study demonstrated that the application of intraoperative TEE for infants undergoing ASO is very helpful in predicting the development of early postoperative neo-PS.

We report two cases of complete transposition of the great arteries with pulmonary venous obstruction which was diagnosed by intraoperative transesophageal echocardiography, but was not detected by transthoracic echocardiography and cardiac catheterization. The pulmonary venous obstruction was relieved simultaneously with arterial switch operation. The intraoperative transesophageal echocardiography has great contribution for thorough evaluation of the pulmonary venous return of the patients.