P03.10: Prenatal echocardiography for detecting isolated total anomalous pulmonary venous connection by four-dimensional ultrasound

Abstract

Prenatal diagnosis of TAPVC is important for appropriate prenatal counseling and perinatal management. Two cases of isolated total anomalous pulmonary venous connection (TAPVC) were missed in routine fetal ultrasound screening performed at 26 weeks gestational age. Though correct diagnoses were not made prenatally, two-dimensional echocardiography showed some abnormalities; in first case (TAPVC IIa), abnormal wall inside left atrium (LA), abnormal blood flow to right atrium, and turbulent flow in the entry to coronary sinus; in second case (TAPVC III), small LA with slow pulmonary venous (PV) flow (10cm/s). We re-scrutinized fetal echocardiography from datasets acquired with 4-dimensional echocardiograms in which we used spatio-temporal image correlation (STIC), color Doppler STIC and Virtual Organ Computed-aided AnaLysis (VOCAL). In TAPVC (IIa) case, 4D echocardiography visualized small (thin) LA, common chamber, PV drainage to coronary sinus and turbulent flow in the entry to coronary sinus. In the other TAPVC (III) case, small LA, common PV chamber, vertical vein, infradiaphragmatic PV drainage, and turbulent flow in the ductus venousus could be visualized. The VOCAL data showed small LA in both TAPVC s. Two D-echocardiographic screening is sometimes not enough for making a correct diagnosis of isolated TAPVC. STIC image can facilitate identifying the anatomical features of TAPVC, a small left atrium, PV confluence behind the left atrium, common PV chamber, a vertical vein and the turbulent flow (by color Doppler STIC) suggesting the obstruction in the PV pathway. We should scrutinize STIC images thoroughly in cases showing rather small LA or slow pulmonary venous flow velocity in the routine 2D-echocardiographic screening.