3D-echocardiography as a diagnostic aid for surgery in tetralogy of Fallot

Background: Current 2-dimensional echocardiography does not always completely disclose the surgical anatomy of tetralogy of Fallot (TF). Methods: Fifteen patients (range 4 months-61 years), undergoing surgical repair for TF, were examined by 3-dimensional (3D) echocardiography. Location and size of the ventricular septal defect (VSD), location and degree of right ventricular outflow tract (RVOT) obstruction, degree of overriding aorta and imaging of coronary arteries were randomly analyzed. Morphological accuracy was assessed postoperatively by comparison with surgical findings. Results: In 14/14 data sets the VSD was accurately reconstructed. In the 11 datasets of the RVOT, 3D-echocardiography showed 10 sub-pulmonary obstructions, 3 bicuspid pulmonary valves and in 3 others a hypoplastic pulmonary trunk. There was aortic overriding of about 50% in 13 patients, less than 50% in 2 patients and more than 50% in 1 patient. Origin and path of coronary arteries could be assessed in only 2 patients. The accuracy of the morphological findings was confirmed by the surgical findings in all the reconstructions. Conclusion: 3D-echocardiography accurately assesses the features of surgical interest in TF. The anatomical insight is improved by depth perception. 3D-echocardiography might be used as an additional tool in determining surgical strategy in TF.