Persistent Left Superior Vena Cava Significance in Prenatal Diagnosis—Case Series

Persistant Left Superior Vena Cava with and Without Right Superior Vena Cava: Significance of Prenatal Diagnosis

This study aims to define the associated anomalies with PLSVC, and to compare single PLSVC and bilateral superior vena cava in terms of accompanying anomalies and pregnancy outcomes. This was a retrospective study of the fetuses diagnosed with single and/or bilateral SVC at a tertiary fetal medicine center during 8 years. We detected 16 cases of single PLSVC and 84 cases of bilateral SVC. We found an association between the PLSVC and cardiac and extracardiac anomalies. Comparison between single PLSVC and BSVC cases revealed significant differences in the occurrence of heterotaxy and right isomerism. The study highlights the importance of prenatal diagnosis in PLSVC cases. Isolated PLSVC with situs solitus may be considered a benign finding, but larger studies are needed to understand the clinical implications of PLSVC in relation to chromosomal anomalies. Routine screening protocols should include three-vessel and trachea views to detect PLSVC.

Integrated analysis of comorbidity, pregnant outcomes, and amniotic fluid cytogenetics of fetuses with persistent left superior vena cava

BACKGROUND

Persistent left superior vena cava (PLSVC) is the most common venous system variant. The clinical characteristics and amniotic fluid cytogenetics of fetuses with PLSVC remain to be further explored.

AIM

To develop reliable prenatal diagnostic recommendations through integrated analysis of the clinical characteristics of fetuses with PLSVC.

METHODS

Cases of PLSVC diagnosed using prenatal ultrasonography between September 2019 and November 2022 were retrospectively studied. The clinical characteristics of the pregnant women, ultrasonic imaging information, gestational age at diagnosis, pregnancy outcomes, and amniocentesis results were summarized and analyzed using categorical statistics and the chi-square test or Fisher's exact test.

RESULTS

Of the 97 cases diagnosed by prenatal ultrasound, 49 (50.5%) had isolated PLSVC and 48 (49.5%) had other structural abnormalities. The differences in pregnancy outcomes and amniocentesis conditions between the two groups were statistically significant (P < 0.05). No significant differences were identified between the two groups in terms of advanced maternal age and gestational age (P > 0.05). According to the results of the classification statistics, the most common intracardiac abnormality was a ventricular septal defect and the most common extracardiac abnormality was a single umbilical artery. In the subgroup analysis, the concurrent combination of intra- and extracardiac structural abnormalities was a risk factor for adverse pregnancy outcomes (odds ratio > 1, P < 0.05). Additionally, all abnormal cytogenetic findings on amniocentesis were observed in the comorbidity group. One case was diagnosed with 21-trisomy and six cases was diagnosed with chromosome segment duplication.

CONCLUSION

Examination for other structural abnormalities is strongly recommended when PLSVC is diagnosed. Poorer pregnancy outcomes and increased amniocentesis were observed in PLSVC cases with other structural abnormalities. Amniotic fluid cytogenetics of fetuses is recommended for PLSVC with other structural abnormalities.