Single-stage arterial switch operation conversion with dextro-transposition of the great arteries and pulmonary arterial hypertension due to baffle leak after a Senning procedure.

Patients who have undergone an atrial switch operation for dextro-transposition of the great arteries (dTGA) sometimes suffer from right ventricular dysfunction, tricuspid regurgitation, arrhythmias, or baffle leaks. We report the first case of single-stage arterial switch operation conversion in an adult patient with dTGA and pulmonary arterial hypertension (PAH) due to a baffle leak after a Senning procedure. Perioperative mechanical circulatory support was required for 3 weeks. Although chronic kidney disease persisted, her left ventricular function and pulmonary hypertension improved over the first postoperative year. This is a rare case, and we believe that the patient's PAH might have helped the left ventricle withstand systemic pumping for over two decades. Learning objective: Patients with dextro-transposition of the great arteries may face problems after an atrial switch operation because their right ventricle is responsible for systemic pumping. Staged arterial switch operation conversion is a strategy that can combat these problems but increases the risk of perioperative mortality. Pulmonary arterial hypertension allows for single-stage arterial switch operation, but the operative risk may be higher.

Novel electrocardiographic criteria for short QT syndrome in children and adolescents.

AIMS: Although shortening of the corrected QT interval (QTc) is a key finding in the diagnosis of short QT syndrome (SQTS), there may be overlap of the QTc between SQTS patients and normal subjects in childhood and adolescence. We aimed to investigate electrocardiographic findings for differentiation of SQTS patients. METHODS AND RESULTS: The SQTS group comprised 34 SQTS patients <20 years old, including 9 from our institutions and 25 from previous reports. The control group comprised 61 apparently healthy subjects with an QTc of <360 ms who were selected from 13 314 participants in a school-based screening programme. We compared electrocardiographic findings, including QT and Jpoint-Tpeak intervals (QT and J-Tpeak, respectively), those corrected by using the Bazett's and Fridericia's formulae (cB and cF, respectively) and early repolarization (ER) between the groups. QT, QTc by using Bazett's formula (QTcB), QTc by using Fridericia's formula (QTcF), J-Tpeak, J-Tpeak cB, and J-Tpeak cF were significantly shorter in the SQTS group than in the control group. On receiver operating characteristic curve analysis, the area under the curve (AUC) was largest for QTcB (0.888) among QT, QTcB, and QTcF, with a cut-off value of 316 ms (sensitivity: 79.4% and specificity: 96.7%). The AUC was largest for J-Tpeak cB (0.848) among J-Tpeak, J-Tpeak cB, and J-Tpeak cF, with a cut-off value of 181 ms (sensitivity: 80.8% and specificity: 91.8%). Early repolarization was found more frequently in the SQTS group than in the control group (67% vs. 23%, P = 0.001). CONCLUSION: A QTcB <316 ms, J-Tpeak cB < 181 ms, and the presence of ER may indicate SQTS patients in childhood and adolescence.

A Nonsense SMAD3 Mutation in a Girl with Familial Thoracic Aortic Aneurysm and Dissection without Joint Abnormality.

INTRODUCTION: Thoracic aortic aneurysms and dissections (TAAD) are rare in children and often associated with underlying genetic disorders accompanied with other systemic manifestations, including connective or osteo-articular tissue diseases. CASE PRESENTATION: We report the case of a 10-year-old girl with a novel nonsense SMAD3 mutation, p.Glu102X, who presented with familial TAAD without any signs of osteoarthritis. Histological analysis of aorta fragments from the patient with TAAD obtained during surgery revealed elastin degradation and inflammatory infiltration of T cells with dense CD31 + microvessels, which is consistent with previous findings. Interestingly, the family members with the SMAD3 mutation developed IgA nephropathy. CONCLUSION: Because the TGF-ß/Smad signalling pathway plays an important role in the primary pathogenesis of IgA nephropathy and TAAD, we presume that IgA nephropathy could be a novel clinical phenotype of SMAD3 deficiency. Further accumulation of genetically proven cases with SMAD3 deficiency is needed to more accurately characterize phenotypic variability and elucidate a wide spectrum of TGF-ß-associated disorders.