Single left superior vena cava: antenatal diagnosis, associated anomalies and outcomes.

OBJECTIVES: To describe the associated cardiac and extracardiac findings and estimate the prevalence of single left superior vena cava (LSVC) among fetuses referred for fetal echocardiography. METHODS: This was a retrospective case series of fetuses diagnosed with situs solitus and single LSVC at the Brompton Centre for Fetal Cardiology, London, UK, from October 2006 to December 2020. Prenatal and postnatal outcome data were collected. Prenatal diagnosis was based on abnormal vessel alignment at the three-vessel view and/or three-vessel-and-trachea view, showing a vessel to the left of the pulmonary artery (i.e. the LSVC) and absence of the usual vessel to the right of the ascending aorta (i.e. the right superior vena cava), and further visualization of the LSVC draining into the coronary sinus. RESULTS: Of 19 968 fetal echocardiograms performed during the study period, 34 cases of single LSVC were identified (a prevalence of 0.17%). Of these, 32 pregnancies had a live birth, one was lost to follow-up and one resulted in intrauterine demise. Single LSVC was isolated in 79.4% of cases. No major congenital heart disease was identified. One fetus showed mild isthmus hypoplasia, with no aortic coarctation postnatally. Two fetuses had umbilical vessel abnormalities. A genetic abnormality was found in one case (15q24.1-q24.2 deletion). CONCLUSIONS: Antenatal diagnosis of single LSVC in the setting of situs solitus is usually a benign isolated finding. Nevertheless, investigation of other cardiac, extracardiac and genetic disorders should be considered. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Predicting 22q11.2 deletion syndrome: a novel method using the routine full blood count.

BACKGROUND: 22q11.2 deletion syndrome is common affecting nearly 1 in 3000, including many with DiGeorge Syndrome and 5% of individuals with congenital heart disease. Diagnosis is important because affected patients have impaired immune function and may suffer high mortality rates if given non-irradiated blood products from graft versus host disease. Symptomatic hypocalcaemia may also occur. Our objective was to determine whether mean platelet volume (MPV), available from the routine full blood count, may be a useful and rapid indicator of 22q11.2 deletion. METHOD: A retrospective case control cohort study analysing MPV and 22q11.2 deletion status was performed in a paediatric population (n = 166) undergoing cardiac surgery between 1999 and 2005. RESULTS: Twenty children were 22q11.2 positive. The median MPV was significantly larger for the 22q11.2 positive patient group compared to the non-22q11.2 patients (10.9fL versus 8.6fL, p<0.001). The area under the curve of the receiver operating characteristics (ROC) curve of MPV was large enough (0.85) to enable the accurate prediction of 22q11.2 deletion using MPV. CONCLUSIONS: MPV is a useful screening test, involving no extra laboratory work, cost or patient discomfort. MPV>10fL is a positive predictor of the presence of 22q11.2 deletion in children with congenital heart disease (specificity 89.7%). This finding should aid rapid decision-making for ordering irradiated blood products to prevent potentially fatal transfusion-associated graft versus host disease. It will alert clinicians to monitor serum calcium levels closely to prevent hypocalcaemic seizures.