Modified technique for coarctation of aorta with hypoplastic distal aortic arch.

BACKGROUND: A combination of coarctation of aorta with various severity of distal arch hypoplasia frequently occurs in newborns. Traditional techniques in the neonatal period such as extended end-to-end anastomosis or inner curve patch are controversial. Arch geometry has a marked role in long-term outcomes. We introduce a modified Amato technique of distal aortic arch enlargement with native tissue-to-tissue reconstruction. METHODS: Neonatal patients with coarctation of aorta and distal aortic arch hypoplasia who underwent surgical reconstruction using this technique between January 2016 and December 2019 in our center were included. Patients with concomitant complex heart defects were excluded. Data were obtained from echo protocols, CT scans before and after repair. The dimensions of the arch were assessed using Z-score, arch geometry was evaluated with height/width ratio. RESULTS: Thirty-two patients (22 males, 10 females) were included. Median age and weight were 7 days (5; 18) and 3.5 kg (3.1; 4.0), respectively. The Z-score of distal part of the arch before and after procedure was significantly different (<0.01). No mortality, recoarctation, or bronchial compression was found during 18 (6-38) months of follow-up. CONCLUSION: Modified technique for coarctation of aorta with hypoplastic distal aortic arch provides favorable geometry of the aorta with a low risk of morbidity. The proper selection and accurate technique could minimize potential risks. This method is relatively safe and might improve long-term outcomes associated with the geometry of aorta.

Dysregulation of Notch signaling in cardiac mesenchymal cells of patients with tetralogy of Fallot.

BACKGROUND: Tetralogy of Fallot (TF) is a severe congenital defect of heart development. Fine-tuned sequential activation of Notch signaling genes is responsible for proper heart chamber development. Mutations in Notch genes have been associated with TF. The aim of this study was to analyze the activity of the Notch pathway in cardiac mesenchymal cells derived from ventricular tissue of TF patients. METHODS: Cardiac mesenchymal cells were isolated from 42 TF patients and from 14 patients with ventricular septal defects (VSDs), used as a comparison group. The Notch pathway was analyzed by estimating the expression of Notch-related genes by qPCR. Differentiation and proliferation capacity of the cells was estimated. RESULTS: The TF-derived cells demonstrated a dysregulated pattern of Notch-related gene expression comparing to VSD-derived cells. Correlation of Notch signaling activation level by HEY1/HES1 expression level with proliferation and cardiogenic-like differentiation of cardiac mesenchymal cells was observed but not with clinical parameters nor with the age of the patients. CONCLUSIONS: The data suggest a contribution of dysregulated Notch signaling to the pathogenesis of tetralogy of Fallot and importance of Notch signaling level for the functional state of cardiac mesenchymal cells, which could be critical considering these cells for potential cell therapy approaches.