[Two-dimensional echocardiographic assessment of systemic-pulmonary shunts in infants with cyanotic heart disease].

The growth of pulmonary arteries following systemic-pulmonary arterial shunt procedures in infants with cyanotic heart disease is a determining factor to the prognoses of those patients. We assessed the validity of two-dimensional echocardiography (2DE) in evaluating pulmonary arterial growth following shunt procedures. Blood flow through the shunts was measured at the times of surgery, and the correlations between shunt flows and postoperative clinical courses were studied. 2DE was validated by its assessments of the right pulmonary artery (RPA) with an excellent correlation between the RPA diameter on 2DE and that on angiography (r = 0.97) and/or the actual RPA diameter measured at the times of surgery (r = 0.96) in 20 patients. Ten patients with tetralogy of Fallot and pulmonary atresia were studied by 2DE pre- and postoperatively. The RPA diameters of six patients with effective shunts increased from 5.7 +/- 1.7 mm to 8.5 +/- 1.5 mm during six months after the shunts and their left ventricular end-diastolic dimensions also increased significantly. But the RPA diameters in four patients with ineffective shunts did not show significant increases after the shunts. The shunt flows were correlated with the diameters of the anastomoses. The shunts which were obstructed within two years showed shunt flows of 83 +/- 26 ml/min, while the shunts which were patent for more than two years showed shunt flows of 320 +/- 126 ml/min. Serial measurements of RPA diameters by 2DE serve as a useful method of following patients after systemic-pulmonary shunts. The amounts of shunt flows were correlated with post-operative clinical courses over two year periods.