Analysis of clinical features of neonates with congenital heart disease who develop necrotizing enterocolitis: a retrospective case-control study.

Background: Infants with congenital heart disease (CHD) are known to have higher rates of necrotizing enterocolitis (NEC). Although the etiology is recognized as distinct from the premature neonatal population, there is not a universal consensus regarding etiology or specific risk factors. To analyze the clinical features of neonates with CHD who develop NEC. Methods: A retrospective study of neonates with CHD in the cardiac intensive care unit (ICU) between 2015 and 2018 was performed, and modified Bell's criteria were used to diagnose NEC. Patients were divided into 2 groups according to ductal-dependent (DD) lesions, and were further stratified by Risk Adjustment for Congenital Heart Surgery-1 (RACHS-1) score and Aristotle score, to compare the differences. Results: Among 412 patients with CHD, 69 (16%) developed NEC. The incidence of NEC was notably higher among DD patients than among non-DD (nDD) patients (18.7% vs. 11.1%; P=0.04). Patients with RACHS-1 >2 also had a higher rate of NEC than did those with RACHS-1 ≤2 (19.49% vs. 9.29%; P=0.01). nDD patients who developed NEC were younger, had a lower gestational age (36.25±1.88 vs. 38.10±1.28 weeks; P=0.00), a lower weight (2.86±0.85 vs. 3.33±0.55 kg; P=0.01), and a lower birth weight (2.79±0.79 vs. 3.26±0.55; P=0.01) compared to the DD group. All nDD patients developed NEC after congenital heart surgery, while only 38 cases (76%), NEC occurred after heart surgery in the DD group. Four patients needed surgery for NEC in the DD group and RACHS-1 >2 group. Presence of NEC was not associated with an increased risk of mortality in any group. Conclusions: NEC is a common complication in neonates with CHD and can occur both before and after CHD operations. Likely there are varying mechanism for NEC in different forms of CHD. While NEC is more common in patients with DD CHD and those with more complex forms of CHD, there was no significant difference observed in weight-for-age Z-score (WAZ) between the DD group during follow-up.

Subepicardial lipoma of the posterior atrioventricular sulcus in children: a case report and review of the literature.

Cardiac lipoma is rarely reported in the pediatric population. We reported a case of subepicardial lipoma of the posterior atrioventricular sulcus in a child. The tumor was resected successfully and the patient recovered well after the operation.

Elevated Arterial-Central Venous Carbon Dioxide Partial Pressure Difference Indicates Poor Prognosis in the Early Postoperative Period of Open Heart Surgery in Infants with Congenital Heart Disease.

BACKGROUND: Elevated arterial-central venous carbon dioxide partial pressure difference (AVCO2) may be an important marker to predict tissue and organ hypoperfusion in adults. We analyzed the hemodynamic data of infants with congenital heart disease who underwent corrective repair with cardiopulmonary bypass (CPB) to identify whether AVCO2 has clinical significance in early postoperative tissue hypoperfusion, occurrence of complications, and clinical outcomes. METHODS: Infants with clinical conditions of hypoperfusion, without volume responsiveness and with ineffective initial treatment, within 3 h of cardiac surgery were enrolled in this study. A pulse contour cardiac output catheter was used to monitor the cardiac index (CI). Eight measurements of arterial blood gas and central venous blood gas were taken within 42 h after surgery. Clinical data of all patients were recorded. RESULTS: A total of 69 children were enrolled in this study. Arteriovenous oxygen difference, AVCO2, lactic acid level, and vasoactive inotropic score in the hypoperfusion group (oxygen supply/oxygen consumption ratio [DO2/VO2] of ≤ 2) were significantly higher than those in the non-hypoperfusion group (DO2/VO2 > 2), while the CI in the hypoperfusion group was significantly lower than that in the non-hypoperfusion group. The cutoff value of AVCO2 to predict DO2/VO2 ≤ 2 was 12.3 within 42 h of surgery with area under the curve of 0.84. High AVCO2 is more likely to be associated with some complications and prolonged mechanical ventilation and length of stay in the intensive care unit. CONCLUSION: Elevated AVCO2 within 42 h of CPB in infants is associated with tissue and organ hypoperfusion and incidence of complications. Persistent or repeated increase in AVCO2 indicates poor prognosis.

Preoperative Morphological Prediction of Early Reoperation Risk After Primary Repair in Tetralogy of Fallot: A Contemporary Analysis of 83 Cases.

This study was conducted to investigate the pulmonary artery (PA) variations in tetralogy of Fallot (TOF) and preoperative morphological predictors for early reoperation. Eighty-three TOF patients and 20 children with normal PA were included. The TOF group was divided into two subsets according to whether or not reoperation was performed within 3 years postoperatively. Clinical information was obtained, along with computed tomography (CT)-based three-dimensional geometry of the PA. Morphological measurements of the length of the main PA branches, the angles between them, and the cross-sectional area of each segment of the PAs were acquired using computer software. Logistic regression and receiver operating characteristic curves were applied to analysis. The TOF group showed a significantly smaller PA size and irregular PA shape, with lower Nakata and McGoon indices, than the control group. The median bifurcation angle (angle-γ) was greater than 100° in the TOF group, as compared to 66.70° in the control group (P < 0.000). Residual obstruction of the infundibulum or PAs was the main reason for early reoperation in this series. The development of the main PA and left PA was poorer in the reoperation subset than in the non-reoperation subset (P ≤ 0.01). The preoperative angle-γ in the reoperation subset was larger than that in the non-reoperation subset (median, 117.8° vs. 112.0°, P = 0.026). Higher weight (OR = 0.372) and McGoon index (OR = 0.122) were protective factors, while larger angle-γ (> 114.8°, OR = 5.040) and angle-γ normalized by body surface area (BSA) (γ/BSA > 297.9, OR = 18.860) were risk factors. This study provides an intuitive perspective of PA anatomical variations in TOF. Larger preoperative PA bifurcation angle and γ/BSA were morphological risk predictors of postoperative reoperation in patients with TOF.

Congenitally Corrected Transposition of the Great Arteries: Mid-term Outcomes of Different Surgical Strategies.

BACKGROUND: Optimal management for congenitally corrected transposition of the great arteries (ccTGA) is controversial. We applied different surgical strategies based on individual variations in our single-centered practice over 10 years, aming to describe the mid-term results. METHODS: From January 2008 to June 2021, 90 patients with ccTGA were reviewed and grouped by three different surgical strategies: 41 cases with biventricular correction as biventricular group, 11 cases with 1.5 ventricular correction as 1.5 ventricular group, and 38 cases with Fontan palliation as univentricular group. The mean age at primary surgery was 41.4 ± 22.7 months. Patients were followed for mortality, complications, reoperation, cardiac function, and valve status. RESULTS: The median follow-up period was 5.1 years (range, 1.5-12.5 years). The overall 10-year survival and freedom from reoperation rate was 86.7 and 82.4%, respectively. There were 3 early deaths and 3 mid-term deaths in the biventricular group, while 2 early deaths and 1 mid-term deaths were reported in the univentricular group. Although 1.5 ventricular group presented no death and the fewest complications, we still found similar mortality (p = 0.340) and morbidity (p = 0.670) among the three groups. The bypass time, aortic-clamp time, and ICU stay length were the longest in the biventricular group, followed by the 1.5 ventricular group (p < 0.001). However, in mid-term follow-up, biventricular and 1.5 ventricular groups both showed excellent cardiac function and obvious improvement of tricuspid regurgitation (p = 0.008 and p = 0.051, respectively). Fontan palliation provided acceptable mid-term outcomes as well, despite a lower ejection fraction. CONCLUSION: Satisfactory mid-term outcomes could be achieved for highly selected ccTGA patients using the whole spectrum of surgical techniques. Moreover, 1.5 ventricular correction, as a new emerging technique in recent years, might hold great promise in future practice.

Impact of 3D Printing on Short-Term Outcomes of Biventricular Conversion From Single Ventricular Palliation for the Complex Congenital Heart Defects.

Background: Although Fontan palliation seems to be inevitable for many patients with complex congenital heart defects (CHDs), candidates with appropriate conditions could be selected for biventricular conversion. We aimed to summarize our single-center experience in patient selection, surgical strategies, and early outcomes in biventricular conversion for the complex CHD. Methods: From April 2017 to June 2021, we reviewed 23 cases with complex CHD who underwent biventricular conversion. Patients were divided into two groups according to the development of the ventricles: balanced ventricular group (15 cases) and imbalanced ventricular group (8 cases). Early and short-term outcomes during the 30.2 months (range, 4.2-49.8 months) follow-up period were compared. Results: The overall mortality rate was 4.3% with one death case. In the balanced ventricular group, 6 cases received 3D printing for pre-operational evaluation. One case died because of heart failure in the early postoperative period. One case received reoperation due to the obstruction of the superior vena cava. In the imbalanced ventricular group, the mean left ventricular end-diastolic volume was (33.6 ± 2.1) ml/m2, the mean left ventricular end-diastolic pressure was 9.1 ± 1.9 mmHg, and 4 cases received 3D printing. No death occurred while one case implanted a pacemaker due to a third-degree atrioventricular block. The pre-operational evaluation and surgery simulation with a 3D printing model helped to reduce bypass time in the balanced group (p < 0.05), and reduced both bypass and aorta clamp time in the imbalanced group (p < 0.05). All patients presented great cardiac function in the follow-up period. Conclusion: Comprehensive evaluation, especially 3D printing technique, was conducive to finding the appropriate cases for biventricular conversion and significantly reduced surgery time. Biventricular conversion in selected patients led to promising clinical outcomes, albeit unverified long-term results.

Pulmonary Hypoplasia Resulting from Pulmonary Artery Banding in Infancy: A Neonatal Rat Model Study.

The aim of this study was to establish a neonatal rat model of decreased pulmonary blood flow (PBF) for studying pulmonary pathophysiological changes in newborn lung development with reduced PBF. Horizontal thoracotomy surgery with banding of the main pulmonary artery (PA) was performed on 30 rats in the PA banding (PAB) group and without banding on another 30 rats in the sham group within 6 h after birth. The body growth and mortality were recorded. Constriction of PA was checked by echocardiography on postnatal day 7 (P7). Lung morphology was assessed with computed tomography scanning and three-dimensional reconstruction. Histological differences of two groups were evaluated using hematoxylin and eosin (H&E) staining, Masson's trichrome staining, TdT-mediated dUTP nick-end labeling assay, and CD31 labeling with microscopic examination. PA ultrasound confirmed the establishment of constriction on P7. Relative to the sham group, the neonates' physical growth, survival fraction, and lung geometry volume were decreased in the PAB group over time (p < 0.05). Histologic appearance with reduced PBF characterized a markedly simplified alveolarization with noted lower radial alveolar count and alveolar septal thickness in the PAB group (p < 0.0001), pulmonary arteries with thinner/uneven membranous layers and smaller lumina. The deficient alveolar capillary bed, enhanced pulmonary collagen deposition, and increased apoptotic alveolar epithelium were significant in the PAB group compared to the sham group (p < 0.0001). A neonatal rat PAB model demonstrated that PBF reduction during early infancy impairs alveolarization and pulmonary microvasculature.

Neonatal Rabbit Model for Pressure-Overloaded Heart Failure and Preliminary Exploration of Mechanism.

BACKGROUND: This study aimed to establish a model of pediatric heart failure (PHF) with concomitant left ventricle pressure overload by transverse aortic constriction (TAC) and study the PHF mechanism primarily at the gene transcription level. METHODS: Twenty-four neonatal rabbits within 7 days after birth were randomly divided into sham (n = 8), moderate TAC (50% constriction, n = 8) and severe TAC (sTAC; 75% constriction, n = 8) groups. After the procedure transthoracic echocardiography was performed at 2, 4, and 6 weeks to measure left ventricle structure and function. Histologic staining and gene sequencing of left ventricle myocardial tissue were performed at 6 weeks. RESULTS: Six weeks after procedure transthoracic echocardiography showed that the pressure at the ligation of the aorta was 12.13 ± 0.95 mm Hg in the sTAC group, which was 26 times more than that of the sham group (P < .05), and left ventricular dilatation began to appear in the sTAC group. Gene sequencing showed significantly different microRNA expression between the sTAC and sham groups. Bioinformatics analysis among the 3 groups showed that the expression of ocu-miR-411-5p, ocu-miR-214-3p, and ocu-miR-432-5p was decreased in the sTAC group compared with the sham group (P < .05) and that the focal adhesion, insulin, and PI3K-Akt signaling pathways were also affected. CONCLUSIONS: Aortic constriction of 75% was optimal for the establishment of the PHF model. The expression of ocu-miR-411-5p, ocu-miR-214-3p, and ocu-miR-432-5p was significantly decreased, and the focal adhesion, insulin, and PI3K/AKT pathways may play significant roles in PHF progression.

miR-381-abundant small extracellular vesicles derived from kartogenin-preconditioned mesenchymal stem cells promote chondrogenesis of MSCs by targeting TAOK1.

Small extracellular vesicles (sEVs) derived from mesenchymal stem cells have been shown to possess potent regenerative potential. In this study, we evaluated the chondrogenic effect of sEVs derived from kartogenin-preconditioned human umbilical cord mesenchymal stem cells (hUCMSCs). sEVs were isolated from the supernatants of KGN-preconditioned hUCMSCs (KGN-sEV) by gradient ultra-centrifugation, and internalized by native hUCMSCs, thereby inducing the chondrogenic differentiation. The underlying mechanism of KGN-sEV-induced chondrogenesis was explored by high-throughput sequencing and verified by transfection with the corresponding mimic and inhibitor. Sequencing identified the unique enrichment of a set of miRNAs in KGN-sEV compared with sEVs derived from unpreconditioned cells (un-sEV). Overexpression/inhibition in vitro and in vivo demonstrated that this chondrogenesis-inducing potential was primarily attributed to miR-381-3p, one of the most abundant miRNAs in KGN-sEV. Dual-luciferase reporter assays showed that miR-381-3p promoted chondrogenesis through direct suppression of TAOK1 by targeting its 3' untranslated region, thereby suppressing the Hippo signaling pathway. Collectively, our results highlight the regenerative potential of KGN-sEV to induce chondrogenic differentiation of MSCs, which is mainly achieved by delivering sEV-miR-381-3p, which targets TAOK1.

Integrated model for the prenatal diagnosis and postnatal surgical treatment of total anomalous pulmonary venous connection: A multidisciplinary collaborative experience and preliminary results.

BACKGROUND: This study aimed to evaluate an integrated model for the prenatal diagnosis and postnatal treatment of total anomalous pulmonary venous connection (TAPVC). METHODS: From January 2014 to December 2018, 11 patients were considered as a prenatally diagnosed group, who would accept the integrated model for prenatal diagnosis and postnatal treatment of TAPVC. Besides, 25 patients as postnatally diagnosed group underwent emergency surgery during the corresponding period at the same age. The perioperative status, survival and risk factors for death were compared between the two groups. RESULTS: In a prenatally diagnosed group, three pregnant women chose termination; eight patients followed the integrated model, and their newborns were rapidly transported to a children's hospital within 24 hours after birth. Other than one patient who was prenatally diagnosed with infracardiac type was later confirmed as a mixed type of TAPVC, the prenatal and postnatal diagnoses of the other seven patients were consistent. The 30-day, 1-year, and 5-year survival rates in the prenatally diagnosed group were 100%, 100%, and 100%, while those in the postnatally diagnosed group were 92%, 87.8%, and 87.8%, without significant difference (P > .05). Although Fisher's exact test indicated that an oxygen saturation <70% at admission might be an independent predictor of mortality (P < .01), none of the risk factors for death were significantly different by multivariate Cox regression analysis. CONCLUSION: The integrated model of prenatal diagnosis and postnatal treatment by multidisciplinary collaboration could lead to satisfactory outcomes, and prenatal diagnosis combined with postnatal oxygen saturation evaluation would facilitate early intervention for TAPVC.

Long-segmental tracheal reconstruction in rabbits with pedicled Tissue-engineered trachea based on a 3D-printed scaffold.

Long-segmental tracheal defects constitute an intractable clinical problem, due to the lack of satisfactory tracheal substitutes for surgical reconstruction. Tissue engineered artificial substitutes could represent a promising approach to tackle this challenge. In our current study, tissue-engineered trachea, based on a 3D-printed poly (l-lactic acid) (PLLA) scaffold with similar morphology to the native trachea of rabbits, was used for segmental tracheal reconstruction. The 3D-printed scaffolds were seeded with chondrocytes obtained from autologous auricula, dynamically pre-cultured in vitro for 2 weeks, and pre-vascularized in vivo for another 2 weeks to generate an integrated segmental trachea organoid unit. Then, segmental tracheal defects in rabbits were restored by transplanting the engineered tracheal substitute with pedicled muscular flaps. We found that the combination of in vitro pre-culture and in vivo pre-vascularization successfully generated a segmental tracheal substitute with bionic structure and mechanical properties similar to the native trachea of rabbits. Moreover, the stable blood supply provided by the pedicled muscular flaps facilitated the survival of chondrocytes and accelerated epithelialization, thereby improving the survival rate. The segmental trachea substitute engineered by a 3D-printed scaffold, in vitro pre-culture, and in vivo pre-vascularization enhanced survival in an early stage post-operation, presenting a promising approach for surgical reconstruction of long segmental tracheal defects. STATEMENT OF SIGNIFICANCE: We found that the combination of in vitro pre-culture and in vivo pre-vascularization successfully generated a segmental tracheal substitute with bionic structure and mechanical properties similar to the native trachea of rabbits. Moreover, the stable blood supply provided by the pedicled muscular flaps facilitated the survival of chondrocytes and accelerated epithelialization, thereby improving the survival rate of the rabbits. The segmental trachea substitute engineered by a 3D-printed scaffold, in vitro pre-culture, and in vivo pre-vascularization enhanced survival in an early stage post-operation, presenting a promising approach for surgical reconstruction of long segmental tracheal defects.

Kartogenin preconditioning commits mesenchymal stem cells to a precartilaginous stage with enhanced chondrogenic potential by modulating JNK and ß-catenin-related pathways.

Cartilage engineering strategies using mesenchymal stem cells (MSCs) could provide preferable solutions to resolve long-segment tracheal defects. However, the drawbacks of widely used chondrogenic protocols containing TGF-ß3, such as inefficiency and unstable cellular phenotype, are problematic. In our research, to optimize the chondrogenic differentiation of human umbilical cord MSCs (hUCMSCs), kartogenin (KGN) preconditioning was performed prior to TGF-ß3 induction. hUCMSCs were preconditioned with 1 µM of KGN for 3 d, sequentially pelleted, and incubated with TGF-ß3 for 28 d. Then, the expression of chondrogenesis- and ossification-related genes was evaluated by immunohistochemistry and RT-PCR. The underlying mechanism governing the beneficial effects of KGN preconditioning was explored by phosphorylated kinase screening and validated in vitro and in vivo using JNK inhibitor (SP600125) and ß-catenin activator (SKL2001). After KGN preconditioning, expression of fibroblast growth factor receptor 3, a marker of precartilaginous stem cells, was up-regulated in hUCMSCs. Furthermore, the KGN-preconditioned hUCMSCs efficiently differentiated into chondrocytes with elevated chondrogenic gene ( SOX9, aggrecan, and collagen II) expression and reduced expression of ossific genes (collagen X and MMP13) compared with hUCMSCs treated with TGF-ß3 only. Phosphokinase screening indicated that the beneficial effects of KGN preconditioning are directly related to an up-regulation of JNK phosphorylation and a suppression of ß-catenin levels. Blocking and activating tests revealed that the prochondrogenic effects of KGN preconditioning was achieved mainly by activating the JNK/Runt-related transcription factor (RUNX)1 pathway, and antiossific effects were imparted by suppressing the ß-catenin/RUNX2 pathway. Eventually, tracheal patches, based on KGN-preconditioned hUCMSCs and TGF-ß3 encapsulated electrospun poly( l-lactic acid-co-ε-caprolactone)/collagen nanofilms, were successfully used for restoring tracheal defects in rabbit models. In summary, KGN preconditioning likely improves the chondrogenic differentiation of hUCMSCs by committing them to a precartilaginous stage with enhanced JNK phosphorylation and suppressed ß-catenin. This novel protocol consisting of KGN preconditioning and subsequent TGF-ß3 induction might be preferable for cartilage engineering strategies using MSCs.-Jing, H., Zhang, X., Gao, M., Luo, K., Fu, W., Yin, M., Wang, W., Zhu, Z., Zheng, J., He, X. Kartogenin preconditioning commits mesenchymal stem cells to a precartilaginous stage with enhanced chondrogenic potential by modulating JNK and ß-catenin-related pathways.

Inhibition of microglial activation by minocycline reduced preoligodendrocyte injury in a neonatal rat brain slice model.

BACKGROUND: Periventricular leukomalacia is a common white-matter injury after neonatal cardiac surgery; however, its potential cellular mechanism remains uncertain. There is limited study regarding periventricular leukomalacia treatment. METHODS: A neonatal rat brain slice perfusion model was used for reproducing the condition of cardiopulmonary bypass, and oxygen glucose deprivation simulated circulatory arrest. Seven-day-old Sprague-Dawley rats were randomly divided into 7 groups: (1) control group with 36°C; (2) 60 minutes of oxygen glucose deprivation group on 15°C, 25°C, 36°C, respectively; and (3) 60 minutes of oxygen glucose deprivation group on 15°C, 25°C, 36°C, plus minocycline (10 µmol/L), respectively. Immunohistochemistry, Western blot, and inflammatory mediators were compared after the perfusion procedures in the different groups. RESULTS: This neonatal rat brain slice perfusion with oxygen glucose deprivation model could replicate the pathophysiologic process and injury after cardiopulmonary bypass and hypothermic circulatory arrest. With the increase of oxygen glucose deprivation perfusion temperature, we found that both microglia activation and preoligodendrocyte loss increased. The application of minocycline can significantly inhibit microglial activation and preoligodendrocyte cells loss in the normothermic (36°C) and moderate hypothermia (25°C) oxygen glucose deprivation groups (P < .05), with accompanying significant decreasing microglial inflammatory productions; however, no significant improvement was found in the deep hypothermia (15°C) group. CONCLUSIONS: The microglial activation may play a key role in preoligodendrocyte injury in the ex vivo neonatal rat brain slice perfusion and circulatory arrest model. Inhibition of microglial activation with minocycline may be an attractive target for white-matter protection during cardiopulmonary bypass and hypothermic circulatory arrest.

Restoring tracheal defects in a rabbit model with tissue engineered patches based on TGF-ß3-encapsulating electrospun poly(l-lactic acid-co-ε-caprolactone)/collagen scaffolds.

Long segment tracheal stenosis often has a poor prognosis due to the limited availability of materials for tracheal reconstruction. Tissue engineered tracheal patches based on electrospun scaffolds and stem cells present ideal solutions to this medical challenge. However, the established engineering process is inefficient and time-consuming. In our research, to optimize the engineering process, core-shell nanofilms encapsulating TGF-ß3 were fabricated as scaffolds for tracheal patches. The morphological and mechanical characteristics, degradation and biocompatibility of poly(l-lactic acid-co-ε-caprolactone)/collagen (PLCL/collagen) scaffolds with different compositions (PLCL:collagen 75:25, 50:50 and 25:75, respectively) were comparatively evaluated to determine the preferable compositional ratio. Then the chondrogenesis-inducing potential is investigated, and tracheal patches based on electrospun scaffolds and bone marrow mesenchymal stem cells (BMSCs) were constructed to restore tracheal defects in rabbit models. The results indicated that core-shell scaffolds with a PLCL/collagen proportion of 75:25 were eligible for tracheal patches. The stable and sustained release of TGF-ß3 from scaffolds could efficiently promote the chondrogenic differentiation of BMSCs and shorten the incubation time. Tracheal integrity was well maintained for 2 months after restoration; meanwhile, re-epithelialization also achieved. In conclusion, TGF-ß3-encapsulating core-shell electrospun scaffolds with a PLCL/collagen proportion of 75:25 could be used to optimize engineering process of tracheal patches.

Outcomes of Right Ventricular Outflow Tract Reconstruction for Children with Persistent Truncus Arteriosus: A 10-Year Single-Center Experience.

The purpose of this report is to assess the mid- and long-term outcomes of right ventricular outflow tract (RVOT) reconstruction for children with persistent truncus arteriosus. Between September 2006 and 2016, 105 patients with persistent truncus arteriosus (PTA) received surgical treatment at Shanghai Children's Medical Center. Direct right ventricle-pulmonary artery anastomosis (pulmonary artery pull-down) was performed in 51 patients; a left auricle or pericardial conduit was inserted between the RVOT and pulmonary artery as a connection in 17 patients; heterograft (bovine jugular vein or Gore-tex) conduits and homograft conduits were used in 30 and 7 cases, respectively, to connect the distal pulmonary and right ventricle outflow tract; and pulmonary valve reconstruction was performed in 38 patients using a Gore-tex monocusp. There were six in-hospital deaths and one delayed death 5 months after operation. After a mean follow-up of 55.8 ± 16.5 months (6-113 months), 19 patients underwent reoperation (3 with pulmonary patch enlargement, 14 with conduit replacement and 2 with aortic valve replacement) 10-89 months after the first operation, with 1 hospital death. The actuarial survival rates were 94.2, 93.3 and 93.3% at 1, 5 and 10 years, respectively. Freedom from reoperation was 98.0, 87.8 and 82.7% at 1, 5 and 10 years, respectively. The follow-up variables included echocardiography, chest radiography, cardiac CT and cardiac function. At the last examination, most of the patients exhibited an improvement of New York Heart Association functional class from III or IV preoperatively to I or II at follow-up. Surgical treatment for PTA has an acceptable survival rate and satisfactory outcomes. Most patients exhibited an improvement in cardiac function during follow-up. Aortic arch deformity, truncal valvular regurgitation and long cardiopulmonary bypass time were regarded as risk factors for hospital mortality. Autologous tissue has a lower reoperation rate and better growth potential than extracardiac conduits. A monocusp valve effectively reduces pulmonary regurgitation in the early postoperative stage.

Surgical strategies and outcomes of congenital supravalvular aortic stenosis.

BACKGROUND: Various surgical techniques have been introduced to treat supravalvular aortic stenosis (SVAS). However, there is no consensus upon the optimal approach. This study reviewed our institutional experience in the management of SVAS. METHODS: Ninety patients undergoing surgery for SVAS were identified between 2009 and 2016. Based on surgical techniques, patients were divided into three groups: McGoon repair (n = 63), Doty repair (n = 24), and Brom repair (n = 3). Median follow-up was 38.5 months (range, 4 months-7.5 years). Patient status, cumulative event-free survival rate, and risk factors for adverse clinical outcomes were assessed. RESULTS: The early mortality rate was 3.3%. There was one late death and two reinterventions. No differences were observed among three surgical groups. Event-free survival was 98.4% at 3 years and 96.5% at 5 years. Diffuse-type SVAS and a preoperative gradient greater than 60 mmHg were risk factors for adverse cardiac remodeling within 6 months post-surgery. Residual aortic stenosis was associated with male gender, preoperative aortic valve stenosis, and a preoperative peak gradient greater than 90 mmHg. Eleven patients (out of 30) who underwent concomitant pulmonary artery patching had a residual pulmonary gradient greater than 40 mmHg. CONCLUSIONS: Surgical repair of SVAS can be safely achieved using different techniques, with similar midterm mortality and reintervention rates. Higher preoperative gradient is associated with worse clinical results. Issues regarding surgical timing and concomitant pulmonary artery stenosis need to be further addressed.

Single-Stage Correction for Taussig-Bing Anomaly Associated With Aortic Arch Obstruction.

Taussig-Bing anomaly and aortic arch obstruction are two types of complex congenital cardiac malformations. Almost 50% of patients with Taussig-Bing anomaly have aortic arch obstruction. This report assesses the surgical outcomes of single-stage correction in neonates with both defects. Between November 2006 and November 2015, 39 neonates with Taussig-Bing anomaly and aortic arch obstruction (28 patients with coarctation of the aorta and 11 patients with interrupted aortic arch) underwent a one-stage arterial switch operation and aortic reconstruction. There were three in-hospital deaths and one late death (8 months after the surgery). The short-term survival rate was 92.3% (36/39), and the mid-term survival rate was 89.7% (35/39). Follow-up data were available for all patients who survived the operation (range 6-92 months). Echocardiology showed six cases of recoarctation, three cases of left ventricular outflow tract obstruction, three cases of right ventricular outflow tract obstruction, four cases of pulmonary artery stenosis, five cases of aortic regurgitation, and eight cases of pulmonary regurgitation. Eight patients required a reoperation during the follow-up period with no mortality. All survivors remained in good condition (New York Heart association functional class I or II). Single-stage correction of Taussig-Bing anomaly with aortic arch obstruction in neonates had favorable short- and mid-term outcomes in terms of mobility and reoperation rate. The optimal operative procedure should be chosen according to the position of the coronary arteries and the type of aortic anomaly.

Tissue-engineered trachea from a 3D-printed scaffold enhances whole-segment tracheal repair.

Long segmental repair of trachea stenosis is an intractable condition in the clinic. The reconstruction of an artificial substitute by tissue engineering is a promising approach to solve this unmet clinical need. 3D printing technology provides an infinite possibility for engineering a trachea. Here, we 3D printed a biodegradable reticular polycaprolactone (PCL) scaffold with similar morphology to the whole segment of rabbits' native trachea. The 3D-printed scaffold was suspended in culture with chondrocytes for 2 (Group I) or 4 (Group II) weeks, respectively. This in vitro suspension produced a more successful reconstruction of a tissue-engineered trachea (TET), which enhanced the overall support function of the replaced tracheal segment. After implantation of the chondrocyte-treated scaffold into the subcutaneous tissue of nude mice, the TET presented properties of mature cartilage tissue. To further evaluate the feasibility of repairing whole segment tracheal defects, replacement surgery of rabbits' native trachea by TET was performed. Following postoperative care, mean survival time in Group I was 14.38 ± 5.42 days, and in Group II was 22.58 ± 16.10 days, with the longest survival time being 10 weeks in Group II. In conclusion, we demonstrate the feasibility of repairing whole segment tracheal defects with 3D printed TET.

Age-Dependent Oxidative DNA Damage Does Not Correlate with Reduced Proliferation of Cardiomyocytes in Humans.

BACKGROUND: Postnatal human cardiomyocyte proliferation declines rapidly with age, which has been suggested to be correlated with increases in oxidative DNA damage in mice and plays an important role in regulating cardiomyocyte proliferation. However, the relationship between oxidative DNA damage and age in humans is unclear. METHODS: Sixty right ventricular outflow myocardial tissue specimens were obtained from ventricular septal defect infant patients during routine congenital cardiac surgery. These specimens were divided into three groups based on age: group A (age 0-6 months), group B (age, 7-12 months), and group C (>12 months). Each tissue specimen was subjected to DNA extraction, RNA extraction, and immunofluorescence. RESULTS: Immunofluorescence and qRT-PCR analysis revealed that DNA damage markers-mitochondrial DNA copy number, oxoguanine 8, and phosphorylated ataxia telangiectasia mutated-were highest in Group B. However immunofluorescence and qRT-PCR demonstrated that two cell proliferation markers, Ki67 and cyclin D2, were decreased with age. In addition, wheat germ agglutinin-staining indicated that the average size of cardiomyocytes increased with age. CONCLUSIONS: Oxidative DNA damage of cardiomyocytes was not correlated positively with age in human beings. Oxidative DNA damage is unable to fully explain the reduced proliferation of human cardiomyocytes.

Total Anomalous Pulmonary Venous Connection: The Current Management Strategies in a Pediatric Cohort of 768 Patients.

BACKGROUND: Total anomalous pulmonary venous connection (TAPVC) is a rare form of congenital heart disease. This study describes current surgical treatment strategies and experiences in a cohort of patients from 2 congenital cardiac centers in Shanghai and Guangdong in China. METHODS: This retrospective study included 768 patients operated on between 2005 and 2014. Although most patients (n=690) underwent conventional repair, a sutureless technique was used in 10% (n=78) of cases. A multilevel mixed-effects parametric survival model and a competing-risk analysis were used to analyze associated risk factors for death and recurrent pulmonary venous obstruction (PVO), respectively. Kaplan-Meier analysis was used to analyze the overall survival. The Nelson-Aalen cumulative risk curve was used to compare distributions of time with recurrent PVO. RESULTS: The mean surgical age and weight were 214.9±39.2 days and 5.4±3.6 kg, respectively. Obstructed TAPVC (PVO) was documented in 192 (25%) of the 768 patients. There were 38 intraoperative deaths and 13 late deaths. A younger age at the time of repair (P=0.001), mixed (P=0.004) and infracardiac (P=0.035) TAPVC, preoperative PVO (P=0.027), prolonged cardiopulmonary bypass time (P<0.001), and longer duration of ventilation (P=0.028) were associated with mortality. The median follow-up was 23.2 months (range; 1-112 months). Among the 717 survivors, recurrent PVO was observed in 111 patients (15%). Associated risk factors for recurrent PVO included preoperative PVO (P<0.001), infracardiac TAPVC (P<0.001), mixed TAPVC (P=0.013), and prolonged cardiopulmonary bypass time (P<0.001). Sutureless technique was associated with a lower restenosis rate compared with conventional repair in patients with preoperative PVO (P=0.038), except in newborn patients (P=0.443). Reintervention for restenosis was performed in 24 patients. The function of most survivors (91%) was classified according to the New York Heart Association as functional class I or II. CONCLUSIONS: Surgical correction in patients with TAPVC with a biventricular anatomy can achieve an acceptable outcome. Risk factors such as a younger age at the time of repair, infracardiac and mixed TAPVC, and preoperative PVO were associated with a poorer prognosis.