Objectives: This study was designed to identify echocardiographic predictors of aortopulmonary collaterals (APCs) in infants with tetralogy of Fallot and pulmonary atresia (TOF/PA) and to prospectively validate these predictors.
Background: In patients with TOF/PA, routine preoperative diagnostic cardiac catheterization is usually performed to determine the presence and distribution of APCs and the anatomy of the branch pulmonary arteries.
Methods: The clinical and diagnostic imaging data of infants with TOF/PA treated between 1990 and 2000 were reviewed. Patients were classified into two groups based on cineangiographic findings: 1) no APCs (n = 34), and 2) >or=1 APCs (n = 59). Echocardiographic variables were examined for their ability to identify patients having >or=1 APCs.
Results: Median branch pulmonary artery diameter Z scores were significantly larger in patients without APCs compared with those having >or=1 APCs: -0.56 versus -3.24 for the left pulmonary artery and -0.76 versus -3.46 for the right pulmonary artery (p < 0.001). The presence of a branch pulmonary artery diameter Z score <or=-2.5 was 88% sensitive and 100% specific for the presence of >or=1 APCs. Detection of APCs by color Doppler was 93% sensitive and 91% specific. A combination of branch pulmonary artery diameter Z score <or=-2.5 or patent ductus arteriosus diameter <or=2 mm was 97% sensitive and 100% specific for the presence of >or=1 APCs. The diagnostic accuracy of these echocardiographic variables was subsequently validated in a prospective study of 11 infants.
Conclusions: Echocardiography is a sensitive and specific test for the detection of >or=1 APCs in infants with TOF/PA. These data can be used to select patients who can undergo complete repair of TOF/PA without further preoperative diagnostic imaging.