The Use of the CardioCel 3D 60° Patch for Aortic Arch Reconstruction in Infancy - A Word of Caution.

BACKGROUND: There is limited data on outcomes following implantation of Cardiocel 3D 60° patch in great vessel repair. After anecdotally witnessing an increase in negative outcomes, we reviewed our experience using this patch in our neonate and infant patients undergoing aortic arch repair. METHODS: A total of 24 patients underwent aortic arch repair with implantation of CardioCel 3D 60° patch between July 2018 to July 2021. Dominant cardiac morphologies were Hypoplastic Left Heart Syndrome (66%), Atrioventricular Canal defects (13%) and Other (21%). Median age at implantation was 44 days (IQR 6-112). Recurrent obstruction was defined as need for reoperation or catheter intervention or recurrent peak pressure gradient of descending aorta ≥ 25 mm Hg on echocardiography. RESULTS: Five deaths occurred after median 217 days (IQR 69-239). Twelve patients (50%) had recurrent obstruction. Three patients (13%) required redo aortic arch operation after a median of 148 days (IQR 128-193), with extensive fibrous coating of the patch interior causing obstruction. Eleven patients (46%) required at least one balloon angioplasty on their aorta after a median of 102 days (IQR 83-130) following repair, and three needed more than one catheter intervention. The estimated probability of having recurrent obstruction at 6 months was 85% and at 1 year follow up was 71% (p=0.06). CONCLUSIONS: Recurrent aortic obstruction occurred in half of our patients shortly after repair. The use of the CardioCel 3D 60° patch for aortic arch reconstruction in neonates and infants should be re-evaluated.

Validating the Concept of Mechanical Circulatory Support with a Rotary Blood Pump in the Inferior Vena Cava in an Ovine Fontan Model.

Right-sided mechanical support of the Fontan circulation by existing devices has been compounded by the cross-sectional design of vena cava anastomosis to both pulmonary arteries. Our purpose was to investigate whether increasing inferior vena cava (IVC) flow with a rotary blood pump in the IVC only in an ovine animal model of Fontan would lead to acceptable superior vena cava (SVC) pressure. To achieve this, a Fontan circulation was established in four female sheep by anastomosing the SVC to the main pulmonary artery (MPA) and by interposing a Dacron graft between the IVC and the MPA. A rotary blood pump was then introduced in the graft, and the effect of incremental flows was observed at increasing flow regimen. Additionally, to stimulate increased pulmonary resistance, the experience was repeated in each animal with the placement of a restrictive band on the MPA distally to the SVC and Dacron graft anastomosis. Circulatory support of IVC flow alone increased the systemic cardiac output significantly, both with and without banding, indicating the feasibility of mechanical support of the Fontan circulation by increasing the flow only in the inferior vena cava. The increase in SVC pressure remained within acceptable limits, indicating the potential effectiveness of this mode of support. The findings suggest that increasing the flow only in the inferior vena cava is a feasible method for mechanical support of the Fontan circulation, potentially leading to an increase in cardiac output with acceptable increases in superior vena cava pressure.

Immunofluorescence Protocol for Characterization of Platelet and Leukocyte Binding in Extracorporeal Membrane Oxygenation (ECMO) Circuits.

The continuous contact between blood and the foreign surface of the extracorporeal membrane oxygenation (ECMO) circuit contributes to hemostatic, inflammatory, and other physiological disturbances observed during ECMO. Although previous studies have extensively investigated blood samples from patients on ECMO, cell adsorption to the ECMO circuit as an additional factor that could potentially influence clinical outcomes, has largely been overlooked. Here we provide a detailed immunofluorescence (IF) protocol designed to characterize cellular binding on ECMO circuits collected from patients. Extracorporeal membrane oxygenation circuits were collected from three pediatric patients and an albumin primed-only ECMO circuit was used as control. Circuit samples from five different sites within each ECMO circuit were collected and processed for the IF protocol. CD14 and CD42a antibodies were used to identify platelets and leukocytes bound to each ECMO circuit sample and images captured using inverted fluorescence microscopy. The protocol enables the comprehensive characterization of platelet and leukocyte binding to ECMO circuits collected from patients, which could in turn extend our knowledge of the characteristics of circuit binding and may provide guidance for improved ECMO circuit design.

Wellbeing in Children and Adolescents with Fontan Physiology.

OBJECTIVE: To assess health-related quality of life (HRQOL) and global quality of life (QOL) in children and adolescents with Fontan physiology and identify key predictors influencing these outcomes. STUDY DESIGN: Cross-sectional analysis of 73 children and adolescents enrolled in the Australia and New Zealand Fontan Registry aged 6-17 years, at least 12 months post-Fontan operation. Assessments included the Pediatric Quality of Life Inventory (PedsQL) for HRQOL and a developmentally-tailored visual analogue scale (0-10) for global QOL, along with validated sociodemographic, clinical, psychological, relational, and parental measures. Clinical data were provided by the Australia and New Zealand Fontan Registry. RESULTS: Participants (mean age: 11.5 ± 2.6 years, 62% male) reported lower overall HRQOL (P < .001), and lower scores across all HRQOL domains (all P < .0001), compared with normative data. Median global QOL score was 7.0 (IQR 5.8-8.0), with most participants (79%) rating their global QOL ≥6. Anxiety and depressive symptoms requiring clinical assessment were reported by 21% and 26% of participants, respectively. Age, sex, and perceived seriousness of congenital heart disease explained 15% of the variation in HRQOL scores, while depressive symptoms and treatment-related anxiety explained an additional 37% (final model: 52% of variance explained). For global QOL, sociodemographic and clinical factors explained 13% of the variance in scores, while depressive symptoms explained a further 25% (final model: 38% of variance explained). Parental factors were not associated with child QOL outcomes. CONCLUSIONS: Children and adolescents with Fontan physiology experience lower HRQOL than community-based norms, despite reporting fair overall QOL. Psychological factors predominantly influenced QOL outcomes, indicating strategies to bolster psychological health could improve QOL in this population.

The Society of Thoracic Surgeons Clinical Practice Guidelines on the Management of Neonates and Infants with Coarctation.

BACKGROUND: Although coarctation of the aorta without concomitant intracardiac pathology is relatively common, there is lack of guidance regarding aspects of its management in neonates and infants. METHODS: A panel of experienced congenital cardiac surgeons, cardiologists, and intensivists was created, and key questions related to the management of isolated coarctation in neonates and infants were formed using the PICO (Patients/Population, Intervention, Comparison/Control, Outcome) Framework. A literature search was then performed for each question. Practice guidelines were developed with classification of recommendation and level of evidence using a modified Delphi method. RESULTS: For neonates and infants with isolated coarctation, surgery is indicated in the absence of obvious surgical contraindications. For patients with risk factors for surgery, medical management before intervention is reasonable. For those stable off prostaglandin E1, the threshold for intervention remains unclear. Thoracotomy is indicated when arch hypoplasia is not present. Sternotomy is preferable when arch hypoplasia is present that cannot be adequately addressed through a thoracotomy. Sternotomy may also be considered in the presence of a bovine aortic arch. Antegrade cerebral perfusion may be reasonable when the repair is performed through a sternotomy. Extended end-to-end, arch advancement, and patch augmentation are all reasonable techniques. CONCLUSIONS: Surgery remains the standard of care for the management of isolated coarctation in neonates and infants. Depending on degree and location, arch hypoplasia may require a sternotomy approach as opposed to a thoracotomy approach. Significant opportunities remain to better delineate management in these patients.

Connecting Transcriptomics with Computational Modeling to Reveal Developmental Adaptations in the Human Pediatric Myocardium.

Background: Nearly 1% or 1.3 million babies are born with congenital heart disease (CHD) globally each year - many of whom will require palliative or corrective heart surgery within the first few years of life. A detailed understanding of cardiac maturation can help to expand our knowledge on cardiac diseases that develop during gestation, identify age-appropriate cardiovascular drug therapies, and inform clinical care decisions related to surgical repair, myocardial preservation, or postoperative management. Yet, to date, our knowledge of the temporal changes that cardiomyocytes undergo during postnatal development is largely limited to animal models. Methods: Right atrial tissue samples were collected from n=117 neonatal, infant, and pediatric patients undergoing correct surgery due to (acyanotic) CHD. Patients were stratified into five age groups: neonate (0-30 days), infant (31-364 days), toddler to preschool (1-5 years), school age (6-11 years), and adolescent to young adults (12-32 years). We measured age-dependent adaptations in cardiac gene expression, and used computational modeling to simulate action potential and calcium transients. Results: Enrichment of differentially expressed genes (DEG) was explored, revealing age-dependent changes in several key biological processes (cell cycle, cell division, mitosis), cardiac ion channels, and calcium handling genes. Gene-associated changes in ionic currents exhibited both linear trends and sudden shifts across developmental stages, with changes in calcium handling ( I NCX ) and repolarization ( I K1 ) most strongly associated with an age-dependent decrease in the action potential plateau potential and increase in triangulation, respectively. We also note a shift in repolarization reserve, with lower I Kr expression in younger patients, a finding likely tied to the increased amplitude of I Ks triggered by elevated sympathetic activation in pediatric patients. Conclusion: This study provides valuable insights into age-dependent changes in human cardiac gene expression and electrophysiology among patients with CHD, shedding light on molecular mechanisms underlying cardiac development and function across different developmental stages.

Survival benefits of the wait-and-grow approach in small babies (≤2000 g) requiring heart surgery.

Objective: The best approach to minimize the observed higher mortality of newborn infants with low birth weight who require congenital heart surgery is unclear. This retrospective study was designed to review outcomes of newborn infants weighing <2000 g who have undergone cardiovascular surgery to identify patient parameters and clinical strategies for care associated with higher survival. Methods: A retrospective chart review of 103 patients who underwent cardiovascular surgery from 2010 to 2021 who were identified as having low birth weight (≤2000 g). Patients who underwent only patent ductus arteriosus ligation or weighing >3500 g at surgery were excluded. Results: Median age was 24 days and weight at the time of surgery was 1920 g. Twenty-six (25%) operative mortalities were recorded. Median follow-up period was 2.7 years. The 1- and 3-year overall Kaplan-Meier survival estimate was 72.4% ± 4.5% and 69.1% ± 4.6%. The 1-year survival of patients who had a weight increase >300 g from birth to surgery was far superior to the survival of those who did not achieve such a weight gain (81.4% ± 5.6% vs 64.0% ± 6.7%; log-rank P = .04). By multivariable Cox-hazard regression analysis, the independent predictor of 1-year mortality was genetic syndrome (hazard ratio, 3.54; 95% CI, 1.67-7.82; P < .001), whereas following a strategy of increasing weight from birth to surgery resulted in lower mortality (hazard ratio, 0.49; 95% CI, 0.24-0.90; P = .02). Conclusions: A strategy of wait and grow for newborn infants with very low birth weight requiring heart surgery results in better survival than immediate surgery provided that the patient's condition allows for this waiting period.

Excellent Survival With a Focus on Pulmonary Artery Reinterventions After the Arterial Switch Operation.

Background: We sought to evaluate the outcomes in patients who underwent the arterial switch operation (ASO) over a 20-year period at a single institution. Methods: The current study is a retrospective review of 180 consecutive patients who underwent the ASO for biventricular surgical correction of dextro-transposition of the great arteries (d-TGA) between 2002 and 2022. Results: Among 180 patients, 121 had TGA-intact ventricular septum, 47 had TGA-ventricular septal defect and 12 had Taussig-Bing Anomaly (TBA). The median follow-up time was 6.7 years (interquartile range: 3.9-8.7 years). There were five early (2.8%) and one late (0.6%) mortality. Survival was 96.6% at one year and beyond. Reoperations were performed in 31 patients (17%). Taussig Bing Anomaly was found to increase the risk of reoperation by 17 times (P < .0001). A total of 37 (21%) patients underwent 53 reinterventions (14 surgical procedures, 39 catheter interventions) specifically addressing pulmonary artery (PA) stenosis. Freedom from PA reintervention was 97%, 87%, 70%, and 55% at 1, 5, 10, and 15 years, respectively. By bivariable analysis, TBA (P = .003, odds ratio [OR]: 6.4, 95% confidence interval [CI]: 1.9-21.7), mild PA stenosis at discharge (P ≤ .001, OR: 6.1, 95% CI: 2.7-13.6), and moderate or severe PA stenosis at discharge (P ≤ .001, OR: 12.7, 95% CI: 5-32.2) were identified as predictors of reintervention on PA. In the last follow-up of 174 survivors, 24 patients (14%) had moderate or greater PA stenosis, two (1%) had moderate neoaortic valve regurgitation, and 168 were New York Heart Association status I. Conclusions: Our results demonstrated excellent survival and functional status following the ASO for d-TGA; however, patients remain subject to frequent reinterventions especially on the pulmonary arteries.

Exercise Capacity and Reoperation Late After Transatrial Fallot Repair.

BACKGROUND: The exercise capacity long after repair of tetralogy of Fallot, when performed exclusively with a transatrial repair, is unclear. It is also unknown whether echocardiography and cardiopulmonary exercise testing can predict the risk of reoperation in this patient group. METHOD: We retrospectively reviewed the clinical records of 59 patients who underwent cardiopulmonary exercise testing after transatrial Fallot repair at a single centre. Patients underwent cardiopulmonary exercise testing at a mean age of 16.6±4.4 years, and at 15.3±4.1 years after Fallot repair. RESULTS: At testing, the volume of oxygen consumption at maximal exercise (VO2 max) was 71%±13% and the oxygen pulse was 80%±17% of predicted values. Seventeen (17) patients (29%) had a VO2 max superior to 80% of the predicted value. Thirty-two (32) patients (56%) had severe pulmonary regurgitation, three (5%) had moderate pulmonary regurgitation, and 12 (21%) had mild pulmonary regurgitation. After a mean of 7.8±3.9 years following cardiopulmonary exercise testing (23±5.3 years after the repair), 21 (40%) patients underwent reoperation. Right ventricular dilation and systolic function on echocardiography were both significantly associated with subsequent reoperation rates. Patients who had severe right ventricular dilation were eight times more likely to undergo subsequent reoperation (hazard ratio 8.67; 1.82-41.3; p=0.007). No cardiopulmonary exercise testing variable independently predicted reoperation. CONCLUSIONS: The exercise capacity at adolescence following transatrial repair of tetralogy of Fallot is maintained at around 70% of predicted values. Only the patients with normal right ventricular size and normal right ventricular function seemed to be protected from reoperation over the subsequent decade. We found no exercise variables which predicted reoperation.

Repair of the complete atrioventricular septal defect-impact of postoperative moderate or more regurgitation.

OBJECTIVES: To study the risk factors for mortality, moderate or more left atrioventricular valve regurgitation (LAVVR) and reoperation after the surgical repair of complete atrioventricular septal defect (cAVSD) in a single centre. METHODS: The current study is a retrospective review of patients who underwent surgical repair of cAVSD between 2000 and 2021. Patients with unbalanced ventricles not amenable to biventricular repair, double outlet right ventricle and malpositioned great arteries were excluded. The clinical predictors of outcome for end points were analysed with univariate and multivariable Cox regression analysis or Fine-Gray modelling for competing risks. Time-dependent end points were estimated using the Kaplan-Meier curve analysis and cumulative incidence curves. RESULTS: The median follow-up time was 2.3 years. Among 220 consecutive patients were 10 (4.6%) operative and 21 late mortalities (9.6%). A total of 26 patients were identified to have immediate postoperative moderate or more regurgitation and 10 of them ultimately died. By multivariable analysis prematurity and having more than moderate regurgitation immediately after the operation were identified as predictors of overall mortality (P = 0.003, P = 0.012). Five- and ten-year survival rates were lower for patients with immediate postoperative moderate or more LAVVR {51.9% [confidence interval (CI): 27.5-71.7%]} when compared to patients without moderate or more regurgitation [93.2% (CI: 87.1-96.4%) and 91.3% (CI: 83.6-95.5%)]. CONCLUSIONS: The patients who undergo cAVSD repair remain subjected to a heavy burden of disease related to postoperative residual LAVVR. Immediate postoperative moderate or more LAVVR contributes significantly to overall mortality. Whether a second run of bypass can decrease this observed mortality should be investigated.

Alarming rate of liver cirrhosis after the small conduit extracardiac Fontan: A comparative analysis with the lateral tunnel.

BACKGROUND: The association between the prevalence of cirrhosis and the types of Fontan operations remains unclear. METHODS: We conducted a retrospective chart review of 332 patients who underwent the Fontan procedure at our institution. Four patients who underwent the atriopulmonary connection Fontan were excluded from the analysis. Patients who had intracardiac-extracardiac conduit (126) between 1989 and 2021 were pooled with those having extracardiac conduit (ECC) (134). The 260 patients who underwent the ECC and the 68 patients who had the lateral tunnel (LT) Fontan constitute the core of the study. RESULTS: Median age at the Fontan procedure was 23.7 months (interquartile range [IQR], 20.8-32.6) in the LT group, compared with 28.8 months (IQR, 24.6-39.5) in the ECC group (P < .01). The median follow-up was 14.8 years (IQR, 12.5-16.5) in the LT group and 7 years (IQR, 2.8-10.4) in the extracardiac conduit group. During the follow-up period, 3 patients (4.4%) with LT and 17 patients (6.5%) with ECC (11 patients with 16 mm or less conduit size) were diagnosed with cirrhosis. The prevalence of cirrhosis at 1, 5, 10, and 15 years was 0%, 0%, 0%, and 4.4% in the LT group, respectively, and 0%, 0.9%, 7.7%, and 29.8% in the ECC group (P < .01) Rates of mortality, Fontan revision, Fontan takedown, transplant, and complications were comparable between the 2 groups. CONCLUSIONS: The extracardiac conduit Fontan seems to be associated with faster development of cirrhosis.

Reconstruction of Fibrous Skeleton of the Heart for Double-Valve Replacement in A Pediatric Patient - Modified Commando Procedure.

The so-called Commando procedure, initially described by David and colleagues, consists in the reconstruction of the mitro-aortic fibrous lamina by a patch that enlarges both annuli. Its use has been described to upsize the aortic and mitral annulus for double valve replacement in adolescents. We describe a modified technique of this reconstruction of the fibrous skeleton of the heart, combined with Konno procedure to further enlarge the aortic annulus. In modified Commando procedure, following the reconstruction of aortomitral continuity with a bovine pericardium CardioCel patch (Admedus Regen Pty Ltd, Perth, WA, Australia), an aortic valved conduit that was made on the bench in order to have bottom skirt that enabled the suturing of the composite conduit far inside the left ventricle outflow tract. Coronary buttons were implanted at the supra-commissural level. The advantages of this modified Commando procedure are (1) the creation of a new aortic annulus when the integrity of this annulus has been compromised, (2) the upsizing of both annuli to any possible size of aortic and mitral prostheses, and (3) the relief of any residual left ventricular outflow tract obstruction.

Brain injury and neurodevelopmental outcomes in children undergoing surgery for congenital heart disease.

Objectives: Brain injury is commonly seen on magnetic resonance imaging in infants with complex congenital heart disease. The impact of perioperative brain injury on neurodevelopmental outcomes is not well understood. We evaluate the association of brain injury and other markers on neurodevelopmental outcomes in patients undergoing surgery for congenital heart surgery during infancy. Methods: Term newborns with infant cardiac surgery performed between 2008 and 2019 at a single tertiary center, and both preoperative and postoperative brain magnetic resonance imaging were included. Those with underlying genetic conditions were excluded. Brain injury was characterized using an magnetic resonance imaging scoring system. Neurodevelopmental outcomes were assigned using the Pediatric Stroke Outcome Measure and Glasgow Outcome Scale Extended. Independent risk factors for poor neurodevelopmental outcomes were determined by multivariable Cox regression. Results: A total of 122 patients were included. New or progressive postoperative brain injury was noted in 69 patients (57%). A total of 101 patients (83%) had at least 1 neurodevelopmental assessment (median age 36 months) with an early assessment (5-24 months) performed in 95 children. Multivariable Cox regression analysis of early neurodevelopmental outcomes identified new stroke on postoperative magnetic resonance imaging to be an independent predictor of poor neurodevelopmental outcome. Postoperative peak lactate was an independent predictor of poor outcome assessed by the Pediatric Stroke Outcome Measure and Glasgow Outcome Scale Extended. Conclusions: Our study reveals that evidence of new stroke on magnetic resonance imaging after infant congenital heart surgery is a predictor of poor neurodevelopmental outcomes in early childhood. Postoperative lactic acidosis is associated with poor neurodevelopmental outcome and may be a surrogate biomarker for ischemic brain injury.