The echocardiographic diagnosis of totally anomalous pulmonary venous connection in the fetus

Background-Infants with isolated totally anomalous pulmonary venous return often present severely decompensated, such that they are at high risk for s urgical repair. On the other hand, if surgical repair can be safely accompl ished, the outlook is usually good. Thus prenatal diagnosis would be expect ed to improve the prognosis for the affected child. Objective-To describe the features of isolated totally anomalous pulmonary venous drainage in the fetus. Design-Four fetuses with isolated totally anomalous pulmonary venous connec tion were identified and the echocardiographic images reviewed. Measurement s of the atrial and ventricular chambers and both great arteries were made and compared with normal values. Setting-Referral centre for fetal echocardiography. Results-There were two cases of drainage to the coronary sinus, one to the right superior vena cava, and one to the inferior vena cava. Right heart di latation relative to left heart structures was a feature of two casts early on, and became evident in some ratios late in pregnancy in the remaining t wo. Conclusions-Ventricular and great arterial disproportion in the fetus can i ndicate a diagnosis of totally anomalous pulmonary venous connection above the diaphragm. However, in the presence of an atrial septal defect or with infradiaphragmatic drainage, right heart dilatation may not occur until lat e in pregnancy. The diagnosis of totally anomalous pulmonary venous drainag e in fetal life can only be reliably excluded by direct examination of pulm onary venous blood flow entering the left atrium on colour or pulsed flow m apping.