Transaortic approach to residual ventricular septal shunt after repairing corrected transposition of the great arteries.

Many surgical approaches have been taken when closing ventricular septal defects after correcting transposition of the great arteries in order to avoid postoperative complete heart block. We describe a residual ventricular septal shunt that developed after repair using de Leval's method in a patient with congestive heart failure. The defect was closed transaortically without a complete heart block.

Modified primary sutureless repair of total anomalous pulmonary venous connection in heterotaxy.

Early and late mortality remain high after palliative open heart surgery in low-weight neonates. In addition, the need for neonatal repair and the presence of pulmonary venous obstruction are risk factors for mortality in right isomerism. We describe a modified primary sutureless repair of infracardiac total anomalous pulmonary venous connection in a 1,600 g neonate with heterotaxy. Endarterectomy of intimal hyperplasia localized to the anastomotic site was required at bilateral bidirectional cavopulmonary connection 6 months after the initial repair. The patient underwent a successful fenestrated Fontan procedure using an extracardiac conduit at the age of 2 years.

Differentiation of lymphatic endothelial cells from embryonic stem cells on OP9 stromal cells.

OBJECTIVE: The discovery of vascular endothelial growth factor C (VEGF-C) and VEGF receptor-3 (VEGFR-3) has started to provide an understanding of the molecular mechanisms of lymphangiogenesis. The homeobox gene prox1 has been proven to specify lymphatic endothelial cells (ECs) from blood ECs. We investigated the process of lymphatic EC (LEC) differentiation using embryonic stem (ES) cells. METHODS AND RESULTS: VEGFR-2+ cells derived from ES cells differentiated into LECs at day 3 on OP9 stromal cells defined by the expression of prox1, VEGFR-3, and another lymphatic marker podoplanin. VEGFR-2+ cells gave rise to LYVE-1+ embryonic ECs, which were negative for prox1 on day 1 but turned to prox1+ LECs by day 3. VEGFR-3-Fc or Tie2-Fc, sequestering VEGF-C or angiopoietin1 (Ang1), suppressed colony formation of LECs on OP9 cells. However, addition of VEGF-C and Ang1 in combination with VEGF to the culture of VEGFR-2+ cells on collagen-coated dishes failed to induce LECs. LEC-inducing activity of OP9 cells was fully reproduced on paraformaldehyde-fixed OP9 cells with the conditioned medium. CONCLUSIONS: We succeeded in differentiating LECs from ES cells and revealed the requirements of VEGF-C, Ang1, and other unknown factors for LEC differentiation.

Prospective identification of cardiac progenitors by a novel single cell-based cardiomyocyte induction.

Dissection of cardiomyocyte differentiation process at the cellular level is indispensable in the research for cardiac development and regeneration. Previously, we have established an embryonic stem cell differentiation system that reproduces early vascular development from progenitor cells that express Flk1, a vascular endothelial growth factor receptor, by the combinatory application of 2-dimensional culture and flowcytometry. Here we show that cardiomyocytes can be successfully induced from a single Flk1+ cell on 2-dimensional culture, enabling the direct observation of differentiating cardiomyocytes and the prospective identification of cardiac progenitor potentials. Flk1+ cells could give rise to cardiomyocytes, as well as endothelial cells, from a single cell by the co-culture on OP9 stroma cells in a fusion-independent manner. Among the cell populations in intermediate stages from Flk1+ cells to cardiomyocytes, Flk1+/CXCR4+/vascular endothelial cadherin- cells were cardiac-specific progenitors at the single cell level. Noggin, a bone morphogenetic protein inhibitor, abolished cardiomyocyte differentiation by inhibiting the cardiac progenitor induction. However, wnt inhibitors Dkk-1 or Frizzled-8/Fc chimeric protein augmented, but wnt3a inhibited, cardiomyocyte differentiation. In vitro reproduction of cardiomyocyte differentiation process should be a potent tool for the cellular and molecular elucidation of cardiac development, which would provide various targets for cardiac regeneration.

Left pulmonary arterioplasty--extended end-to-end anastomosis.

Surgical arterioplasty for left pulmonary branch stenosis often produces unsatisfactory results. We report a new operative approach involving a modification of end-to end anastomosis, providing a widely patent and nonredundant anastomosis.

Cusp extension technique for bicuspid aortic valve in Turner-like stigmata.

A 19-year-old girl with bicuspid aortic valve and Turner-like stigmata underwent a successful repair with a cusp extension technique using fresh autologous pericardium for aortic insufficiency. She also had a simultaneous artificial graft replacement for ascending aortic dilatation. Aortic valve function showed no significant stenosis and slight insufficiency 2 years postoperatively. This technique is recommended to avoid a Ross or Ross/Konno procedure because of its ready availability, simplicity and excellent midterm results.

Transannular patching for tetralogy of Fallot with an anomalous right coronary artery.

A 7-year-old girl underwent transannular patching under the mobilized anomalous right coronary artery across the right ventricular outflow to treat progressing infundibular stenosis 6 years after total repair of the tetralogy of Fallot. The procedure completely relieved recurrent stenosis. Simultaneous angiography of the coronary artery and right ventricle were useful in precisely evaluating coronary anatomy.

Atypical infantile form of scimitar syndrome with bronchomalacia.

A male infant presenting with severe heart failure and respiratory distress was diagnosed with a hypoplastic right lung, scimitar syndrome with pulmonary sequestration and multiple anomalous systemic arteries, left bronchomalacia, a large atrial septal defect and coarctation of the aorta. The infant underwent a successful combined treatment of surgical and transcatheter intervention, including coil embolization and endobronchial stenting.