[Characteristics and prognosis of interrupted inferior vena cava with azygous continuation]

Objective: To explore the clinical characteristics of interrupted of the inferior vena cava with azygous continuation and the prognosis. Methods: Retrospective analysis of 21 fetuses diagnosed with interrupted inferior vena cava with azygous continuation among 28 567 pregnant women who underwent routine ultrasound scan. The clinical data, ultrasonographic features, genetic information and prognosis were collected. Results: Interrupted of the inferior vena cava with azygous continuation occurred in 21(0.07%, 21/28 567) of 28 567 patients. Three fetuses (14%, 3/21) complicated with heart and extracardiac malformations, including endocardiac cushion defect, single atrium and single ventricle, double superior vena cava, dextrocardia, asplenia syndrome, visceral heterotaxy, duodenal atresia; six fetuses (29%, 6/21) were associated with cardiac anomalies, such as hypoplastic left heart syndrome, double outlet right ventricle, pulmonary stenosis, ventricular septal defect, persistent left superior vena cava, endocardiac cushion defect and transposition of the great arteries; six cases (29%, 6/21) were only combined with extracardiac malformations, includingasplenia syndrome, visceral heterotaxy, duodenal atresia. Three fetuses (14%, 3/21) were nonorganic abnormalities included thickening of the right ventricle wall, fetal bradycardia, pericardial effusion, hydrops abdominis, increased peak systolic velocity/end diastolic velocity and single umbilical artery. Three fetuses (14%, 3/21) were isolated interrupted inferior vena cava with azygous continuation, but without other anomalies and 2 of them had normal fetal karyotype. Five cases (24%, 5/21) were successfully vaginal delivery, 1 case (5%, 1/21) had cesarean section. After 12-40 months follow-up, we didn't obeserve obviously abnormality, nor any chromosomal abnormality. Ten patients (48%, 10/21) opted for termination of the pregnancy and the autopsies were not done. Five cases (24%, 5/21) were lost to follow up. Conclusions: Interrupted inferior vena cava with azygous continuation are associated with cardiovascular and extracardiac anomalies, cardiac malformation and visceral heterotaxy are the most common anomalies. Visceral heterotaxy should be considered and fetal karyotype should be suggested. In the cases of isolated interrupted inferior vena cava with azygous continuation and normal karyotype, the outcome is favorable.