Prenatal phenotype of 22q11 micro-duplications: A systematic review and report on 12 new cases.

The 22q11 region is prone to generating recurring Copy Number Variations (CNVs) as a result of the large numbers of Low Copy Repeats (LCRs). Typical duplications encompass the LCR-A-to-D region but atypical duplications of various sizes have also been reported. These duplications are responsible for highly variable phenotypes with incomplete penetrance and expressivity, which is challenging for adequate genetic counselling, especially in the prenatal period. To better delineate prenatal phenotypes associated with these CNVs, we report here a clinical and molecular description of twelve cases (9 foetuses and 3 deceased new-borns babies) carrying recurrent 22q11 duplications (diagnosed via aCGH), along with a review of the existing literature. 22q11 duplications were inherited from an apparently healthy parent in almost 60% of the cases. Other CNVs were diagnosed for 8% of the cases. Increased nuchal translucency and cardiac anomalies (CHD) were the most prominent phenotypes observed, along with mild renal and skeletal anomalies. Duplications encompassing the LCR-C-to-D region (and the CRKL gene) seemed more likely to generate CHDs and renal malformations. Cleft lip/palate were observed in foetuses with duplications encompassing the LCR-A-to-B region or the SPECC1L gene, as previously suggested. However, genotype-phenotype correlations remain difficult to ascertain. Second-hit point variants, epigenetic or environmental variations could play a role in the phenotypic variability of 22q11 duplications, but remain a challenge for assessment in the short period of pregnancy.

Cardiovascular events in perimembranous ventricular septal defect with left ventricular volume overload: a French prospective cohort study (FRANCISCO).

The long-term prospective multi-centre nationwide (French) observational study FRANCISCO will provide new information on perimembranous ventricular septal defect with left ventricular overload but no pulmonary hypertension in children older than 1 year. Outcomes will be compared according to treatment strategy (watchful waiting, surgical closure, or percutaneous closure) and anatomic features of the defect. The results are expected to provide additional guidance about the optimal treatment of this specific population, which is unclear at present. BACKGROUND: The management of paediatric isolated perimembranous ventricular septal defect (pmVSD) with left ventricle (LV) volume overload but no pulmonary arterial hypertension (PAH) remains controversial. Three therapeutic approaches are considered: watchful waiting, surgical closure, and percutaneous closure. We aim to investigate the long-term outcomes of these patients according to anatomic pmVSD characteristics and treatment strategy. METHODS: The Filiale de Cardiologie Pediatrique et Congénitale (FCPC) designed the FRANCISCO registry, a long-term prospective nationwide multi-centre observational cohort study sponsored by the French Society of Cardiology, which enrolled, over 2 years (2018­2020), patients older than 1 year who had isolated pmVSD with LV volume overload. Prevalent complications related to pmVSD at baseline were exclusion criteria. Clinical, echocardiographic, and functional data will be collected at inclusion then after 1, 5, and 10 years. A core lab will analyse all baseline echocardiographic data to depict anatomical pmVSD features. The primary outcome is the 5-year incidence of cardiovascular events (infective endocarditis, sub-aortic stenosis, aortic regurgitation, right ventricular outflow tract stenosis, tricuspid regurgitation, PAH, arrhythmia, stroke, haemolysis, heart failure, or death from a cardiovascular event). We plan to enrol 200 patients, given the 10% estimated 5-year incidence of cardiovascular events with a 95% confidence interval of ±5%. Associations linking anatomical pmVSD features and treatment strategy to the incidence of complications will be assessed. CONCLUSIONS: The FRANSCICO study will provide the long-term incidence of complications in patients older than 1 year with pmVSD and LV volume overload. The results are expected to improve guidance for treatment decisions.