The effect of body weight in infants undergoing ventricular septal defect closure: A report from the Nationwide Japanese Congenital Surgical Database.

OBJECTIVE: In infants with ventricular septal defect (VSD) who undergo surgical intervention, body weight, along with age, is frequently thought to be the decisive predictor of morbidity and mortality after surgery; however, its information on quantitative risk assessment is limited. METHODS: All infants (<1 year old) with a fundamental diagnosis of VSD who underwent surgical VSD closure or pulmonary artery banding between 2012 and 2016 were identified from the Japan Cardiovascular Surgery Database Congenital Section. The outcome of interest was a composite end point of all-cause death and major complications within 30 days after surgery. We evaluated the association between body weight at surgery and composite end point using logistic regression models. RESULTS: A total of 4947 cases were analyzed (median age, 125; interquartile range [IQR], 79-193 days; median body weight, 4.94 [IQR, 4.00-6.00] kg), including 4310 cases (87.1%) treated with surgical VSD closure and 637 (12.9%) treated with pulmonary artery banding. The surgical course was uncomplicated in 94.2% of cases, 23 (0.5%) died, and 283 (5.7%) experienced major complications. The risk of the composite end point was higher along with lower body weight (adjusted odds ratio, 1.56 for every -1 kg; 95% confidence interval, 1.30-1.88; P < .001) and plateaued at body weight of approximately >4.5 kg via smoothing spline curve. Importantly, cases with approximately <4.5 kg of body weight had higher predicted risk regardless of age. CONCLUSIONS: Surgical intervention for infants with VSD was safely performed in contemporary practice; however, caution is warranted in lower body weight infants, particularly for infants with approximately <4.5 kg.

Successful management of living donor liver transplantation for biliary atresia with single ventricle physiology-from peri-transplant through total cavopulmonary connection: A case report.

Children with single ventricle physiology have complete mixing of the pulmonary and systemic circulations, requiring staged procedures to achieve a separation of these circulations, or Fontan circulation. The single ventricle physiology significantly increases the risk of mortality in children undergoing non-cardiac surgery. As liver transplantation for patients with single ventricle physiology is particularly challenging, only a few reports have been published. We herein report a case of successful LDLTx for an 8-month-old pediatric patient with biliary atresia, heterotaxy, and complex heart disease of single ventricle physiology. The cardiac anomalies included total anomalous pulmonary venous return type IIb, intermediate atrioventricular septal defect, tricuspid regurgitation grade III, coarctation of aorta, interrupted inferior vena cava, bilateral superior vena cava, and polysplenia syndrome. Following LDLTx, the patient sequentially underwent total cavopulmonary shunt + Damus-Kaye-Stansel at 3 years of age and extracardiac total cavopulmonary connection (EC-TCPC) completion at 5 years of age; 7 years have now passed since LDLTx (2 years post-EC-TCPC). We describe the details of the management of LTx in the presence of cardiac anomalies and report the long-term cardiac and liver function, from peri-LDLTx through EC-TCPC completion.

Palliative Mitral Valve Repair During Infancy for Neonatal Marfan Syndrome.

An infant with neonatal Marfan syndrome (nMFS), a condition that is nearly always lethal during infancy, was referred to our hospital with symptoms of congestive heart failure resulting from severe mitral valve insufficiency. During mitral valve repair, the use of an annuloplasty ring was waived until annular dilatation was achieved after 2 palliative mitral valvuloplasty procedures. After the definitive operation, the patient's mitral valve function remained within normal limits until the last follow-up when the patient was 11 years old. To the best of our knowledge, this patient has the longest recorded survival after mitral valve repair.

Heterotopic transplantation of a decellularized and recellularized whole porcine heart.

OBJECTIVES: One of the final treatments for end-stage heart failure is heart transplantation. However, a shortage of donor hearts has created a long waiting list and limited benefits. Our ultimate goal is to create a whole beating heart fabricated on an organ scaffold for human heart transplantation. Here, we successfully performed the first transplantation using a decellularized whole porcine heart with mesenchymal stem cells. METHODS: A porcine heart was harvested following cardiac arrest induced by a high-potassium solution and stored at -80°C for 24 h. The porcine heart was completely decellularized with 1% sodium dodecyl sulphate and 1% Triton X-100 under the control of perfusion pressure (100 mmHg) and maintained at 37°C. A decellularized whole-heart scaffold was sterilized with gamma irradiation. Cultured mesenchymal stem cells were collected and either infused into the ascending aorta or injected directly into the left ventricular wall. Finally, recellularized whole-heart scaffolds were transplanted into pigs under systemic anticoagulation treatment with heparin. Coronary artery angiography of the transplanted heart graft was performed. RESULTS: In our decellularization method, all cellular components were removed, preserving the heart extracellular matrix. Heterotopic transplantations were successfully performed using a decellularized heart and a recellularized heart. The scaffolds were well perfused, without bleeding from the surface or anastomosis site. Coronary angiography revealed a patent coronary artery in both scaffolds. The transplanted decellularized heart was harvested on Day 3. Haematoxylin and eosin staining showed thrombosis in the coronary arteries and migrated inflammatory cells. Haematoxylin and eosin staining of the transplanted recellularized heart showed similar findings, with the exception of injected mesenchymal stem cells. CONCLUSIONS: To the best of our knowledge, this is the first report of heterotopic transplantation of a decellularized whole porcine heart with mesenchymal stem cells. The scaffolds endured surgical procedures. We detected short-term coronary artery perfusion in the transplanted scaffolds by angiography. Future studies should analyse the histological features of transplanted decellularized scaffolds and optimize the system for recellularization to apply this unique technology clinically.

Fontan completion in a patient with previous liver transplantation.

We present the first case of a successful Fontan completion in a patient with previous liver transplantation. An infant with polysplenia syndrome with a functional single ventricle and biliary atresia had been surgically managed by pulmonary artery banding, Kasai operation and living donor liver transplantation. Subsequently, the patient successfully underwent bidirectional cavopulmonary shunt and total cavopulmonary connection with extracardiac conduit at 3 and 5 years of age, respectively.

Negative pressure therapy for post-sternotomy wound infections in young children.

OBJECTIVES: Post-sternotomy wound infection remains a significant morbidity in congenital and paediatric cardiac surgery. However, the techniques used for this complication in children are not optimal in terms of mortality, morbidity and the use of medical resources. Negative pressure therapy is an effective modality in the treatment in adults, but reports of its use in children are limited. This study evaluated the use of negative pressure therapy in young children for post-sternotomy wound infections. METHODS: From October 2004 to June 2012, 15 consecutive cases of post-sternotomy wound infections in patients ≤6 years of age were managed with negative pressure therapy, and these patients were followed up for ≥12 months after wound closure. The median Aristotle comprehensive complexity score was 9.9 ± 4.0. The infection was identified at a median of 16 days after surgery, and the procedure was performed within 24 h of diagnosis. No additional surgical procedures were applied. RESULTS: No cases of hospital mortality or second surgery for infection control occurred. The median duration until wound closure was 25 days (range: 5-92 days). Further, no patient showed sternal instability at treatment termination. During the mean follow-up period of 45.8 ± 31.3 months after wound closure, no admission occurred for infection recurrence. According to a multivariable analysis, the infection depth and patient weight significantly lengthened treatment duration (P = 0.008 and 0.046, respectively). CONCLUSIONS: Negative pressure therapy is an effective treatment modality for wound infections in paediatric cardiac surgery and results in low morbidity, mortality and medical resource use.

Bilateral banding of malpositioned pulmonary artery branches.

This report presents two rare cases of malpositioned pulmonary artery branches managed by bilateral banding. The left-branch pulmonary artery, originating from and directly superior to the right branch, entered the posterior mediastinum before heading toward the left pulmonary hilum. The ostium of the left branch could not be visualized by midline sternotomy. Therefore, a double-subtraction technique was used to pass the banding tape around the left branch from the right side. The tape location was adjusted and confirmed by intraoperative echocardiography.

Bridging annuloplasty for left atrioventricular valve of partial atrioventricular septal defect.

Residual left atrioventricular valve regurgitation after conventional repair technique for partial atrioventricular septal defect most commonly occurs in the central position. We describe here the technique for bridging annuloplasty on the opposing anterior and posterior annuli of the atrioventricular valve in selected patients with short leaflets.

Fenestrated exclusion of the right ventricle for tricuspid atresia and absent pulmonary valve.

The case of a boy who had an absent pulmonary valve, tricuspid atresia, intact ventricular septum, coronary-to-right-ventricular fistula, and dysplasia of the right ventricular free wall is described. At the bidirectional cavopulmonary shunt procedure, the right ventricular free wall was opened and two major fistula orifices to the cavity were closed with sutures. A fenestrated circular patch was placed in the main pulmonary artery and the right ventricular free wall was plicated. The patient then underwent completion for total cavopulmonary connection. Follow-up catheterization showed that the pulmonary artery was partially excluded with minimal pressure wave conduction from the right ventricle, which significantly shrank. This new approach seems to be effective and reproducible in this particular situation.

Multislice computed tomography is useful for evaluating partial anomalous pulmonary venous connection.

Volume-rendered images, derived from multidetector-row computed tomography (MDCT), can facilitate assessment of the morphology of partial anomalous pulmonary venous connection and are thus useful in pre-operative planning to prevent surgical morbidity and assist post-operative evaluations.

Ross-Konno operation for patients with Shone complex.

We report the cases of 2 pediatric patients who had Shone complex. Each child had severe left ventricular outflow tract obstruction and marginal mitral obstruction, and both underwent the Ross-Konno operation. The mitral valve was left alone. Both patients survived the operations, and serial follow-up echocardiography up to 4 years later showed a decreased or decreasing trend in the peak mitral diastolic velocity. The Ross-Konno procedure can be an acceptable approach for a subgroup of patients who have Shone complex.

Reconstruction of an isolated left subclavian artery in a patient with a right aortic arch and tetralogy of Fallot.

An isolated left subclavian artery (ILSA) is very rarely seen in patients with a right aortic arch. This report describes the case of a 2-year-old boy who underwent ILSA reconstruction during repair of the associated tetralogy of Fallot to prevent future subclavian steal syndrome after surgery.

A case report of surgical correction for congenital mitral regurgitation with subvalvular apparatus abnormality.

We report a successful complex mitral valve plasty using port access minimally invasive cardiac surgery for congenital mitral regurgitation that presented as an abnormality of the subvalvular apparatus. A 16-year-old male patient received a diagnosis of mitral regurgitation resulting from tethering of the anterior mitral leaflet and posterior mitral leaflet caused by an abnormality in papillary muscle insertion and a hypoplastic chordae tendineae. The posterior leaflet was closely tethered to the tips of the papillary muscle with essentially no chordae tendineae. The flexibility of the leaflet was restored by surgically removing the abnormal chordae, and reconstruction of chordae tendinae of the anterior leaflet was carried out using three loops and of the posterior leaflet using one loop with a loop technique method. As an additional procedure for persistent regurgitation, an edge-to-edge technique to the posterior commissure side was performed, after which the mitral regurgitation disappeared.

'Working' cardiomyocytes exhibiting plateau action potentials from human placenta-derived extraembryonic mesodermal cells.

The clinical application of cell transplantation for severe heart failure is a promising strategy to improve impaired cardiac function. Recently, an array of cell types, including bone marrow cells, endothelial progenitors, mesenchymal stem cells, resident cardiac stem cells, and embryonic stem cells, have become important candidates for cell sources for cardiac repair. In the present study, we focused on the placenta as a cell source. Cells from the chorionic plate in the fetal portion of the human placenta were obtained after delivery by the primary culture method, and the cells generated in this study had the Y sex chromosome, indicating that the cells were derived from the fetus. The cells potentially expressed 'working' cardiomyocyte-specific genes such as cardiac myosin heavy chain 7beta, atrial myosin light chain, cardiac alpha-actin by gene chip analysis, and Csx/Nkx2.5, GATA4 by RT-PCR, cardiac troponin-I and connexin 43 by immunohistochemistry. These cells were able to differentiate into cardiomyocytes. Cardiac troponin-I and connexin 43 displayed a discontinuous pattern of localization at intercellular contact sites after cardiomyogenic differentiation, suggesting that the chorionic mesoderm contained a large number of cells with cardiomyogenic potential. The cells began spontaneously beating 3 days after co-cultivation with murine fetal cardiomyocytes and the frequency of beating cells reached a maximum on day 10. The contraction of the cardiomyocytes was rhythmical and synchronous, suggesting the presence of electrical communication between the cells. Placenta-derived human fetal cells may be useful for patients who cannot supply bone marrow cells but want to receive stem cell-based cardiac therapy.

Aortic translocation with autologous tissue.

Aortic translocation, although technically demanding, could be an excellent surgical option for d-transposition of the great vessels and left ventricular outflow tract obstruction. We report a modification of the aortic translocation technique that uses autologous tissue. The aortic root is mobilized from the right ventricle with an extension of infundibular free-wall muscle for use in closure of the ventricular septal defect, which is similar to the technique for harvesting pulmonary autograft in the Ross-Konno procedure. Our modification may offer an even better surgical outcome for aortic translocation.

Use of hemoglobin vesicles during cardiopulmonary bypass priming prevents neurocognitive decline in rats.

BACKGROUND: Homologous blood use is considered to be the gold standard for cardiopulmonary bypass (CPB) priming in infants despite exposure of the patient to potential cellular and humoral antigens. However, the use of hemoglobin vesicles (HbVs), artificial oxygen carriers that encapsulate a concentrated hemoglobin solution within phospholipid bilayer membranes, for CPB priming may prevent neurocognitive decline in infants. The goal of this study was to determine whether HbV use offsets hemodilution caused by patient/priming volume-mismatched CPB and thereby prevents the development of postoperative neurocognitive deficits. METHODS AND RESULTS: CPB was established in 28 male Sprague-Dawley rats (age, 14 to 16 weeks; weight, 450 grams) after cannulation of the tail artery and right atrium. The animals were randomly assigned to 1 of 3 groups: sham surgery (n=9), HbV (-) prime (n=10), or HbV (+) prime (n=9). CPB was conducted for 90 minutes at 200 mL/kg per minute. The hematocrit during CPB was 10.0+/-1.2% in the HbV (+) prime group and 9.9+/-1.3% in the HbV (-) prime group (P=not significant). Learning and memory function were evaluated using 2 different maze tests (Maze-1 and Maze-2, in which the arrival times to the target were measured on the first, third, fifth, and seventh postoperative days). Learning and memory function were significantly better in the HbV (+) prime group than in the HbV (-) prime group (Maze-1, P=0.012; Maze-2, P=0.042); there was no difference between the HbV (+) prime and the sham surgery group. CONCLUSIONS: The use of HbV for CPB priming may serve as a substitute for homologous blood to prevent the unacceptable hemodilution and contribute to maintenance of intact neurocognitive function.

Total cavopulmonary connection: open anastomosis of an extracardiac conduit with vacuum-assisted venous drainage.

Insertion of a tube conduit for total cavopulmonary connection is sometimes technically demanding due to the crumpled stump of the inferior vena cava caused by a tourniquet of the inferior vena cava near the division line. Herein we describe an alternative in which the anastomosis is completed during removal of the tourniquet with the application of vacuum-assisted venous drainage. This new technique may alleviate, if not completely eliminate, a concern associated with total cavopulmonary connection with extracardiac conduit in small patients.

Apico-pulmonary artery conduit repair of congenitally corrected transposition of the great arteries with ventricular septal defect and pulmonary outflow tract obstruction: a 10-year follow-up.

BACKGROUND: In conventional repair of the congenitally corrected transpositions of the great arteries associated with ventricular septal defect and pulmonary outflow tract obstruction, the placement of the left ventricle-pulmonary artery conduit is at risk owing to probable compression by the sternum, heart block, or injury to the mitral anterior papillary muscle. Apical placement of the left ventriculotomy for the inflow conduit rather than in the midportion or base placement may avoid these complications, although this results in a long and winding extracardiac conduit that may be short-lived because of the proliferation of pseudointima. METHODS: Between 1985 and 1990, a nonvalved Dacron woven-fabric graft conduit was placed between the left ventricular apex and pulmonary artery in 5 patients (mean age, 6.2 +/- 1.7 years) who were then followed for at least 10 years. RESULTS: No iatrogenic heart blocks or mitral regurgitation developed. All patients were complaint-free during the follow-up period, although 1 patient who was clinically well died suddenly in the 10th follow-up year. Cardiac catheterization in the 10th follow-up year indicated a pressure gradient of 21 +/- 6 mm Hg across the conduit, and angiography revealed that the conduit diameter was 91% +/- 6% of the original conduit diameter. CONCLUSIONS: The reportedly poor early and late outcomes that occur after a conventional repair of congenitally corrected transpositions of the great arteries associated with ventricular septal defect and pulmonary outflow tract obstruction, which places an extracardiac conduit between the left ventricle and the pulmonary artery, may be partially neutralized by relocating the inflow position to the apex.