Persistent end-diastolic forward flow after pulmonary valve replacement in patients with repaired tetralogy of Fallot.

OBJECTIVES: The clinical significance of persistent end-diastolic forward flow (EDFF) after pulmonary valve replacement (PVR) remains unclear in patients with repaired tetralogy of Fallot. This study aimed to identify the characteristics of these patients and the impact of persistent EDFF on outcomes. METHODS: Of 46 consecutive patients who underwent PVR for moderate to severe pulmonary regurgitation between 2003 and 2019, 23 (50%) did not show EDFF before PVR [group (-)]. In the remaining 23 patients with EDFF before PVR, EDFF was diminished after PVR in 13 (28%) [group (+, -)] and persisted in 10 (22%) [group (+, +)]. The following variables were compared between these 3 groups: (i) preoperative right ventricular (RV) and right atrial volumes measured by magnetic resonance imaging, haemodynamic parameters measured by cardiac catheterization and the degree of RV myocardial fibrosis measured by RV biopsy obtained at PVR and (ii) the post-PVR course, development of atrial arrhythmia and need for intervention. RESULTS: A high RV end-diastolic pressure, a greater right atrial volume index and a greater RV end-systolic volume index before PVR and a high degree of RV fibrosis were significantly associated with persistent EDFF 1 year after PVR. Persistent EDFF was a significant risk factor for postoperative atrial tachyarrhythmia, and catheter ablation and pacemaker implantation were required more frequently in these patients. CONCLUSIONS: Persistent EDFF after PVR could predict a worse prognosis, especially an increased risk of arrhythmia. Close follow-up is required in patients with persistent EDFF for early detection of arrhythmia and prompt reintervention if necessary. CLINICAL TRIAL REGISTRATION NUMBER: Institutional review board of Osaka University Hospital, number 16105.

Autologous skeletal myoblast patch implantation prevents the deterioration of myocardial ischemia and right heart dysfunction in a pressure-overloaded right heart porcine model.

Right ventricular dysfunction is a predictor for worse outcomes in patients with congenital heart disease. Myocardial ischemia is primarily associated with right ventricular dysfunction in patients with congenital heart disease and may be a therapeutic target for right ventricular dysfunction. Previously, autologous skeletal myoblast patch therapy showed an angiogenic effect for left ventricular dysfunction through cytokine paracrine effects; however, its efficacy in right ventricular dysfunction has not been evaluated. Thus, this study aimed to evaluate the angiogenic effect of autologous skeletal myoblast patch therapy and amelioration of metabolic and functional dysfunction, in a pressure-overloaded right heart porcine model. Pulmonary artery stenosis was induced by a vascular occluder in minipigs; after two months, autologous skeletal myoblast patch implantation on the right ventricular free wall was performed (n = 6). The control minipigs underwent a sham operation (n = 6). The autologous skeletal myoblast patch therapy alleviated right ventricular dilatation and ameliorated right ventricular systolic and diastolic dysfunction. 11C-acetate kinetic analysis using positron emission tomography showed improvement in myocardial oxidative metabolism and myocardial flow reserve after cell patch implantation. On histopathology, a higher capillary density and vascular maturity with reduction of myocardial ischemia were observed after patch implantation. Furthermore, analysis of mRNA expression revealed that the angiogenic markers were upregulated, and ischemic markers were downregulated after patch implantation. Thus, autologous skeletal myoblast patch therapy ameliorated metabolic and functional dysfunction in a pressure-overloaded right heart porcine model, by alleviating myocardial ischemia through angiogenesis.

External compression due to seroma of ventricular assist device outflow graft.

A 45-year-old woman with repaired complex congenital heart disease, who underwent placement of Jarvik 2000, a ventricular assist device (VAD) for 4 years, experienced abdominal pain due to outflow graft compression caused by seroma formation between the outflow graft and ringed Gore-Tex graft. We exchanged the pump of Jarvik 2000 and punched several small holes in the new ringed Gore-Tex graft. Seroma formation between the two grafts should be considered as a cause of outflow graft obstruction in patients with the long-term support of VAD, and additional surgical interventions to the ringed Gore-Tex graft may prevent this complication.

Pediatric patient with restrictive cardiomyopathy on staged biventricular assist device support with Berlin Heart EXCOR® underwent heart transplantation successfully: the first case in Japan.

Pure restrictive cardiomyopathy is a strong risk factor for poor outcomes in children with cardiomyopathy on ventricular assist devices. Owing to concomitant right heart failure, children with end-staged restrictive cardiomyopathy who are supported with a ventricular assist device often require a biventricular assist device, which is another risk factor for waitlist mortality in heart transplantation candidates. Herein, we report the case of a 3-year-old boy with pure restrictive cardiomyopathy who successfully underwent heart transplantation after 12 months of support with staged biventricular assist devices. Owing to the progression of diastolic dysfunction, the left ventricular assist device could not provide adequate circulation support. Despite the provision of biventricular assist device support, the patient required a complex management strategy that involved balancing the left and right ventricular assist device supports. We were able to stabilize the patient by careful synchronization of the supports and proceeded to heart transplantation. TRIAL REGISTRATION: Clinical Registration No.: Institutional Review Board of Osaka University Hospital, approval no. 16105.

Autologous skeletal myoblast sheet implantation for pediatric dilated cardiomyopathy: A case report.

BACKGROUND: In children with dilated cardiomyopathy, heart transplantation is the last treatment option. However, new regenerative treatments, such as cell therapy, have attracted scientific attention. We have previously demonstrated the efficacy of autologous skeletal myoblast sheet implantation for treatment of ischemic and dilated cardiomyopathy in adults. Because of the mechanism underlying this cell therapy, a similar effectiveness is expected for patients with pediatric dilated cardiomyopathy. CASE: Herein, we describe the case of a child with dilated cardiomyopathy who underwent an autologous skeletal myoblast sheet implantation, which proved to be safe, and led to sustained maintenance and improvements in cardiac function and clinical status.

Impact of Long-Term Support with Berlin Heart EXCOR® in Pediatric Patients with Severe Heart Failure.

Berlin Heart EXCOR® (BHE) ventricular assist device (VAD) (Berlin Heart, Berlin Heart AG, Berlin, Germany) implantation is prevalent in patients with severe heart failure. However, clinical outcomes of pediatric patients on long-term BHE support remain mainly unknown. This study aimed to report our clinical experience with long-term support of pediatric patients with severe heart failure supported by BHE VAD. Clinical outcomes of 11 patients (median age 8.4 months; two male), who underwent LVAD implantation of the Berlin Heart EXCO® (BHE) VAD (Berlin Heart, Berlin Heart AG, Berlin, Germany) between 2013 and 2017 at our institution were reviewed. The median support period was 312 (range 45-661) days and five patients were supported for more than 1 year. The longest support duration was 661 days. No mortality occurred, and six patients were successfully bridged to heart transplantation, while three patients were successfully weaned off the device. Two patients are currently on BHE support while they await heart transplantation. Four patients had cerebral bleeding or infarction, but only one case of persistent neurological deficit occurred. No fatal device-related infection occurred during LVAD support. BHE VAD can provide long-term support for pediatric patients with severe heart failure with acceptable mortality and morbidity rates with long-term support.

Hand-sewn trileaflet valve in the right ventricular outflow tract.

A 4-year-old girl with pulmonary regurgitation after complete repair of tetralogy of Fallot, underwent an alternative surgical repair for pulmonary valve replacement. Hand-sewn trileaflet valve reconstruction using expanded polytetrafluoroethylene membrane is a feasible method for pulmonary regurgitation in such a young child in whom a large-sized bioprosthetic valve cannot be implanted.

An alternative technique for direct implantation of an anomalous left coronary artery arising from the pulmonary artery with complex coronary arteries.

A 2-month-old patient with anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) underwent an alternative repair involving coronary transfer with the bay window technique because of the very short left main coronary trunk. This procedure is a clinically relevant and feasible technique for ALCAPA with such a delicate coronary artery anomaly.

Modified commissural patch repair in a child with active mitral endocarditis.

A 9-year-old patient with massive destruction of the mitral apparatus caused by active infective endocarditis underwent mitral valve plasty using a modified commissural autologous pericardial patch repair. This procedure is a clinically relevant and feasible technique for pediatric patients with active mitral valve endocarditis.

Novel technique for implantation of a cardioverter defibrillator in children.

An 8-year-old boy with hypertrophic nonobstructive cardiomyopathy with ventricular fibrillation underwent implantation of an implantable cardioverter defibrillator. The lead was inserted through a pursestring suture in the right atrial appendage, and the tip of coil was placed in the right ventricular apex under fluoroscopic guidance. Another defibrillation coil was placed in the back of the left atrium and left ventricle by the transverse sinus. The device wrapped in a monofilament mesh sheet was placed in the intraperitoneal space. This case utilized a new technique for an implantable cardioverter defibrillator implantation in a small child.

Thoracic aortic aneurysm with aortic pseudocoarctation involving the left subclavian artery.

A 39-year-old man with a thoracic aortic aneurysm and pseudocoarctation underwent graft replacement of the distal arch. The left subclavian artery, which rose just after the aneurysm, was also reconstructed at surgery. The aneurysmal wall was extremely thin, and the adventitia and a small amount of medial tissue were found on histologic examination. Thus, surgical treatment was recommended due to risk of rupture. Furthermore, because aneurysms involved the cervical branch, separate reconstruction was also performed. Endovascular intervention is not appropriate for this group of patients because of the complex kinking of the aorta and the extremely thin aneurysmal wall.

Two cases of transthoracic pericardial fenestration for pericardial effusion.

Pericardial effusion and cardiac tamponade are often refractory and difficult to manage. The transthoracic pericardial fenestration which create a window is the conventional procedure for releasing pericardial effusion to the thoracic cavity. We experienced two cases of pericardial fenestration. The first case was a patient with hypertrophic cardiomyopathy with pericardial effusion. She had a thoracic compression fracture, which indicated pericardial fenestration before an orthopedic surgery. The second case was a patient with recurrent cardiac tamponade caused by postpericardiotomy syndrome after off-pump coronary artery bypass grafting. In both cases, the patients underwent left anterior thoracotomy of about 10 cm at the level of the 5th intercostal space. The pericardium was incised within a radius of about 20 mm; furthermore, the fenestrated window was opened to the left thoracic cavity. In this paper, we present our experience of pericardial fenestration and discuss a review of the literature.