Comparing apples to apples: Exploring public reporting of congenital cardiac surgery outcomes based on common congenital heart operations

OBJECTIVE

We sought to simplify reporting of outcomes in congenital heart surgery that compares well-defined patient groups and accommodates multiple stakeholder needs while being easily understandable.

METHODS

We selected 19 commonly performed congenital heart surgeries ranging in complexity from repair of atrial septal defects to the Norwood procedure. Strict inclusion/exclusion criteria ensured the creation of 19 well-defined diagnosis/procedure cohorts. Preoperative, procedural, and postoperative data were collected for consecutive eligible patients from 9 centers between January 1, 2016, and December 31, 2021. Unadjusted operative mortality rates and hospital length of stay for each of the 19 diagnosis/procedure cohorts were summarized in aggregate and stratified by each center.

RESULTS

Of 8572 eligible cases included, numbers in the 19 diagnosis/procedure cohorts ranged from 73 for tetralogy of Fallot repair after previous palliation to 1224 for ventricular septal defect (VSD) repair for isolated VSD. In aggregate, the unadjusted mortality ranged from 0% for atrial septal defect repair to 28.4% for hybrid stage I. There was significant heterogeneity in case mix and mortality for different diagnosis/procedure cohorts across centers (eg, arterial switch operation/VSD, n = 7-42, mortality 0%-7.4%; Norwood procedure, n = 16-122, mortality 5.3%-25%).

CONCLUSIONS

Reporting of institutional case volumes and outcomes within well-defined diagnosis/procedure cohorts can enable centers to benchmark outcomes, understand trends in mortality, and direct quality improvement. When made public, this type of report could provide parents with information on institutional volumes and outcomes and allow them to better understand the experience of each program with operations for specific congenital heart defects.

Longitudinal Evaluation of Congenital Cardiovascular Surgical Performance and Skills Retention Using Silicone-Molded Heart Models

Objective: Hands-on surgical training (HOST) for congenital heart surgery (CHS), utilizing silicone-molded models created from 3D-printing of patients' imaging data, was shown to improve surgical skills. However, the impact of repetition and frequency of repetition in retaining skills has not been previously investigated. We aimed to longitudinally evaluate the outcome for HOST on two example procedures of different technical difficulties with repeated attempts over a 15-week period. Methods: Five CHS trainees were prospectively recruited. Repair of coarctation of the aorta (CoA) and arterial switch operation (ASO) were selected as example procedures of relatively low and high technical difficulty. Procedural time and technical performance (using procedure-specific assessment tools by the participant, a peer-reviewer, and the proctor) were measured. Results: Coarctation repair performance scores improved after the first repetition but remained unchanged at the follow-up session. Likewise, CoA procedural time showed an early reduction but then remained stable (mean [standard deviation]: 29[14] vs 25[15] vs 23[9] min at 0, 1, and 4 weeks). Conversely, ASO performance scores improved during the first repetitions, but decreased after a longer time delay (>9 weeks). Arterial switch operation procedural time showed modest improvements across simulations but significantly reduced from the first to the last attempt: 119[20] versus 106[28] min at 0 and 15 weeks, P = .049. Conclusions: Complex procedures require multiple HOST repetitions, without excessive time delay to maintain long-term skills improvement. Conversely, a single session may be planned for simple procedures to achieve satisfactory medium-term results. Importantly, a consistent reduction in procedural times was recorded, supporting increased surgical efficiency.

Bilateral remote ischemic conditioning in children: A two-center, double-blind, randomized controlled trial in young children undergoing cardiac surgery

Objective

The study objective was to determine whether adequately delivered bilateral remote ischemic preconditioning is cardioprotective in young children undergoing surgery for 2 common congenital heart defects with or without cyanosis.

Methods

We performed a prospective, double-blind, randomized controlled trial at 2 centers in the United Kingdom. Children aged 3 to 36 months undergoing tetralogy of Fallot repair or ventricular septal defect closure were randomized 1:1 to receive bilateral preconditioning or sham intervention. Participants were followed up until hospital discharge or 30 days. The primary outcome was area under the curve for high-sensitivity troponin-T in the first 24 hours after surgery, analyzed by intention-to-treat. Right atrial biopsies were obtained in selected participants.

Results

Between October 2016 and December 2020, 120 eligible children were randomized to receive bilateral preconditioning (n = 60) or sham intervention (n = 60). The primary outcome, area under the curve for high-sensitivity troponin-T, was higher in the preconditioning group (mean: 70.0 ± 50.9 μg/L/h, n = 56) than in controls (mean: 55.6 ± 30.1 μg/L/h, n = 58) (mean difference, 13.2 μg/L/h; 95% CI, 0.5-25.8; P = .04). Subgroup analyses did not show a differential treatment effect by oxygen saturations (pinteraction = .25), but there was evidence of a differential effect by underlying defect (pinteraction = .04). Secondary outcomes and myocardial metabolism, quantified in atrial biopsies, were not different between randomized groups.

Conclusions

Bilateral remote ischemic preconditioning does not attenuate myocardial injury in children undergoing surgical repair for congenital heart defects, and there was evidence of potential harm in unstented tetralogy of Fallot. The routine use of remote ischemic preconditioning cannot be recommended for myocardial protection during pediatric cardiac surgery.

Incremental value of machine learning for risk prediction in tetralogy of Fallot

OBJECTIVE

Machine learning (ML) can facilitate prediction of major adverse cardiovascular events (MACEs) in repaired tetralogy of Fallot (rTOF). We sought to determine the incremental value of ML above expert clinical judgement for risk prediction in rTOF.

METHODS

Adult congenital heart disease (ACHD) clinicians (≥10 years of experience) participated (one cardiac surgeon and four cardiologists (two paediatric and two adult cardiology trained) with expertise in heart failure (HF), electrophysiology, imaging and intervention). Clinicians identified 10 high-yield variables for 5-year MACE prediction (defined as a composite of mortality, resuscitated sudden death, sustained ventricular tachycardia and HF). Risk for MACE (low, moderate or high) was assigned by clinicians blinded to outcome for adults with rTOF identified from an institutional database (n=25 patient reviews conducted by five independent observers). A validated ML model identified 10 variables for risk prediction in the same population.

RESULTS

Prediction by ML was similar to the aggregate score of all experts (area under the curve (AUC) 0.85 (95% CI 0.58 to 0.96) vs 0.92 (0.72 to 0.98), p=0.315). Experts with ≥20 years of experience had superior discriminative capacity compared with <20 years (AUC 0.98 (95% CI 0.86 to 0.99) vs 0.80 (0.56 to 0.93), p=0.027). In those with <20 years of experience, ML provided incremental value such that the combined (clinical+ML) AUC approached ≥20 years (AUC 0.85 (95% CI 0.61 to 0.95), p=0.055).

CONCLUSIONS

Robust prediction of 5-year MACE in rTOF was achieved using either ML or a multidisciplinary team of ACHD experts. Risk prediction of some clinicians was enhanced by incorporation of ML suggesting that there may be incremental value for ML in select circumstances.

Treatment of hypoplastic left heart syndrome: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

This meta-analysis aimed to consolidate existing data from randomised controlled trials on hypoplastic left heart syndrome.

METHODS

Hypoplastic left heart syndrome specific randomised controlled trials published between January 2005 and September 2021 in MEDLINE, EMBASE, and Cochrane databases were included. Regardless of clinical outcomes, we included all randomised controlled trials about hypoplastic left heart syndrome and categorised them according to their results. Two reviewers independently assessed for eligibility, relevance, and data extraction. The primary outcome was mortality after Norwood surgery. Study quality and heterogeneity were assessed. A random-effects model was used for analysis.

RESULTS

Of the 33 included randomised controlled trials, 21 compared right ventricle-to-pulmonary artery shunt and modified Blalock-Taussig-Thomas shunt during the Norwood procedure, and 12 regarded medication, surgical strategy, cardiopulmonary bypass tactics, and ICU management. Survival rates up to 1 year were superior in the right ventricle-to-pulmonary artery shunt group; this difference began to disappear at 3 years and remained unchanged until 6 years. The right ventricle-to-pulmonary artery shunt group had a significantly higher reintervention rate from the interstage to the 6-year follow-up period. Right ventricular function was better in the modified Blalock-Taussig-Thomas shunt group 1-3 years after the Norwood procedure, but its superiority diminished in the 6-year follow-up. Randomised controlled trials regarding medical treatment, surgical strategy during cardiopulmonary bypass, and ICU management yielded insignificant results.

CONCLUSIONS

Although right ventricle-to-pulmonary artery shunt appeared to be superior in the early period, the two shunts applied during the Norwood procedure demonstrated comparable long-term prognosis despite high reintervention rates in right ventricle-to-pulmonary artery shunt due to pulmonary artery stenosis. For medical/perioperative management of hypoplastic left heart syndrome, further randomised controlled trials are needed to deliver specific evidence-based recommendations.

Optimal Surgical Management of Tetralogy of Fallot

Tetralogy of Fallot with pulmonary stenosis has a diverse clinical spectrum with the degree of right ventricular outflow tract obstruction (RVOTO) and size of the branch pulmonary arteries driving clinical management. Optimal surgical management involves consideration of patient clinical status and degree and location (subvalvar, valvar, and supravalvar) of RVOTO. Timing of repair requires multidisciplinary decision-making and complete surgical repair with relief of RVOTO by either transannular patch or valve sparing repair techniques. The central goals of contemporary surgical management of tetralogy of Fallot incorporate maximizing survival, minimizing reintervention, and preserving right ventricular function across the lifespan.

Hybrid palliation versus nonhybrid management for a multi-institutional cohort of infants with critical left heart obstruction

OBJECTIVE

To compare patient characteristics and overall survival for infants with critical left heart obstruction after hybrid palliation (bilateral pulmonary artery banding with or without ductal stenting) versus nonhybrid management (eg, Norwood, primary transplantation, biventricular repair, or transcatheter/surgical aortic valvotomy).

METHODS

From 2005 to 2019, 1045 infants in the Congenital Heart Surgeons' Society critical left heart obstruction cohort underwent interventions across 28 institutions. Using a balancing score propensity analysis, 214 infants who underwent hybrid palliation and 831 infants who underwent nonhybrid management were proportionately matched regarding variables significantly associated with mortality and variables noted to significantly differ between groups. Overall survival between the 2 groups was adjusted by applying balancing scores to nonparametric estimates.

RESULTS

Compared with the nonhybrid management group, infants who underwent hybrid palliation had lower birth weight, smaller gestational age, and higher prevalence of in-utero interventions, noncardiac comorbidities, preoperative mechanical ventilation, absent interatrial communication, and moderate or severe mitral valve stenosis (all P values < .03). Unadjusted 12-year survival after hybrid palliation and nonhybrid management, was 55% versus 69%, respectively. After matching, 12-year survival after hybrid palliation versus nonhybrid management was 58% versus 63%, respectively (P = .37). Among matched infants born weighing <2.5 kg, 2-year survival after hybrid palliation versus nonhybrid management was 37% versus 51%, respectively (P = .22).

CONCLUSIONS

Infants born with critical left heart obstruction who undergo hybrid palliation have more high-risk characteristics and anatomy versus infants who undergo nonhybrid management. Nonetheless, after adjustment, there was no significant difference in 12-year survival after hybrid palliation versus nonhybrid management. Mortality remains high, and hybrid palliation confers no survival advantage, even for lower-birth-weight infants.

Outcomes After Hybrid Palliation for Infants With Critical Left Heart Obstruction

BACKGROUND

Hybrid palliation (bilateral pulmonary artery banding with or without ductal stenting) is an initial management strategy for infants with critical left heart obstruction and serves as palliation until subsequent operations are pursued.

OBJECTIVES

This study sought to determine patient characteristics and factors associated with subsequent outcomes for infants who underwent hybrid palliation.

METHODS

From 2005 to 2019, 214 of 1,236 prospectively enrolled infants within the Congenital Heart Surgeons' Society's critical left heart obstruction cohort underwent hybrid palliation across 24 institutions. Multivariable hazard modeling with competing risk methodology was performed to determine risk and factors associated with outcomes of biventricular repair, Fontan procedure, transplantation, or death.

RESULTS

Preoperative comorbidities (eg, prematurity, low birth weight, genetic syndrome) were identified in 70% of infants (150 of 214). Median follow-up was 7 years, ranging up to 17 years. Overall 12-year survival was 55%. At 5 years after hybrid palliation, 9% had biventricular repair, 36% had Fontan procedure, 12% had transplantation, 35% died without surgical endpoints, and 8% were alive without an endpoint. Factors associated with transplantation were absence of ductal stent, older age, absent interatrial communication, smaller aortic root size, larger tricuspid valve area z-score, and larger left ventricular volume. Factors associated with death were low birth weight, concomitant genetic syndrome, cardiopulmonary bypass use during hybrid palliation, moderate to severe tricuspid valve regurgitation, and smaller ascending aortic size.

CONCLUSIONS

Mortality remains high after hybrid palliation for infants with critical left heart obstruction. Nonetheless, hybrid palliation may facilitate biventricular repair for some infants and for others may serve as stabilization for intended functional univentricular palliation or primary transplantation.

Norwood operation versus comprehensive stage II after bilateral pulmonary artery banding palliation for infants with critical left heart obstruction

OBJECTIVE

To determine patient characteristics and outcomes after Norwood versus comprehensive stage II (COMPSII) for infants with critical left heart obstruction who had prior hybrid palliation (bilateral pulmonary artery banding ± ductal stent).

METHODS

From 23 Congenital Heart Surgeons' Society institutions (2005-2020), 138 infants underwent hybrid palliation followed by either Norwood (n = 73, 53%) or COMPSII (n = 65). Baseline characteristics were compared between Norwood and COMPSII groups. Parametric hazard model with competing risk methodology was used to determine risk and factors associated with outcomes of Fontan, transplantation, or death.

RESULTS

Infants who underwent Norwood versus COMPSII had a higher prevalence of prematurity (26% vs 14%, P = .08), lower birth weight (median 2.8 vs 3.2 kg, P < .01) and less frequent ductal stenting (37% vs 99%; P < .01). Norwood was performed at a median age of 44 days and median weight of 3.5 kg, versus COMPSII at 162 days and 6.0 kg (both P < .01). Median follow-up was 6.5 years. At 5 years after Norwood and COMPSII, respectively; 50% versus 68% had Fontan (P = .16), 3% versus 5% had transplantation (P = .70), 40% versus 15% died (P = .10), and 7% versus 11% are alive without transition, respectively. For factors associated with either mortality or Fontan, only preoperative mechanical ventilation occurred more frequently in the Norwood group.

CONCLUSIONS

Higher prevalence of prematurity, lower birth weight, and other patient-related characteristics in the Norwood versus COMPSII groups may influence differences in outcomes that were not statistically significant for this limited risk-adjusted cohort. The clinical decision regarding Norwood versus COMPSII after initial hybrid palliation remains challenging.

Machine Learning for Prediction of Adverse Cardiovascular Events in Adults With Repaired Tetralogy of Fallot Using Clinical and Cardiovascular Magnetic Resonance Imaging Variables

BACKGROUND

Existing models for prediction of major adverse cardiovascular events (MACE) after repair of tetralogy of Fallot have been limited by modest predictive capacity and limited applicability to routine clinical practice. We hypothesized that an artificial intelligence model using an array of parameters would enhance 5-year MACE prediction in adults with repaired tetralogy of Fallot.

METHODS

A machine learning algorithm was applied to 2 nonoverlapping, institutional databases of adults with repaired tetralogy of Fallot: (1) for model development, a prospectively constructed clinical and cardiovascular magnetic resonance registry; (2) for model validation, a retrospective database comprised of variables extracted from the electronic health record. The MACE composite outcome included mortality, resuscitated sudden death, sustained ventricular tachycardia and heart failure. Analysis was restricted to individuals with MACE or followed ≥5 years. A random forest model was trained using machine learning (n=57 variables). Repeated random sub-sampling validation was sequentially applied to the development dataset followed by application to the validation dataset.

RESULTS

We identified 804 individuals (n=312 for development and n=492 for validation). Model prediction (area under the curve [95% CI]) for MACE in the validation dataset was strong (0.82 [0.74-0.89]) with superior performance to a conventional Cox multivariable model (0.63 [0.51-0.75]; P=0.003). Model performance did not change significantly with input restricted to the 10 strongest features (decreasing order of strength: right ventricular end-systolic volume indexed, right ventricular ejection fraction, age at cardiovascular magnetic resonance imaging, age at repair, absolute ventilatory anaerobic threshold, right ventricular end-diastolic volume indexed, ventilatory anaerobic threshold % predicted, peak aerobic capacity, left ventricular ejection fraction, and pulmonary regurgitation fraction; 0.81 [0.72-0.89]; P=0.232). Removing exercise parameters resulted in inferior model performance (0.75 [0.65-0.84]; P=0.002).

CONCLUSIONS

In this single-center study, a machine learning-based prediction model comprised of readily available clinical and cardiovascular magnetic resonance imaging variables performed well in an independent validation cohort. Further study will determine the value of this model for risk stratification in adults with repared tetralogy of Fallot.

Medium-term Outcome of Prenatally Diagnosed Hypoplastic Left-Heart Syndrome and Impact of a Restrictive Atrial Septum Diagnosed in-utero

OBJECTIVE

Surgical outcome data differs from overall outcomes of prenatally diagnosed fetuses with hypoplastic left heart syndrome (HLHS). Our aim was to describe outcome of prenatally diagnosed fetuses with this anomaly.

METHODS

Retrospective review of prenatally diagnosed classical HLHS at a tertiary hospital over a 13-year period, estimated due dates 01/08/2006 to 31/12/2019. HLHS-variants and ventricular disproportion were excluded.

RESULTS

203 fetuses were identified with outcome information available for 201. There were extra-cardiac abnormalities in 8% (16/203), with genetic variants in 14% of those tested (17/122). There were 55 (27%) terminations of pregnancy, 5 (2%) intrauterine deaths and 10 (5%) babies had prenatally planned compassionate care. There was intention to treat (ITT) in the remaining 131/201(65%). Of these, there were 8 neonatal deaths before intervention, two patients had surgery in other centers. Of the other 121 patients, Norwood procedure performed in 113 (93%), initial hybrid in 7 (6%), and 1 had palliative coarctation stenting. Survival for the ITT group from birth at 6-months, 1-year and 5-years was 70%, 65%, 62% respectively. Altogether of the initial 201 prenatally diagnosed fetuses, 80 patients (40%) are currently alive. A restrictive atrial septum (RAS) is an important sub-category associated with death, HR 2.61, 95%CI 1.34-5.05, p = 0.005, with only 5/29 patients still alive.

CONCLUSION

Medium-term outcomes of prenatally diagnosed HLHS have improved however it should be noted that almost 40% do not get to surgical palliation, which is vital to those doing fetal counselling. There remains significant mortality particularly in fetuses with in-utero diagnosed RAS.

Outcomes of the arterial switch for transposition during infancy using a standardised approach over 30 years

OBJECTIVES

To describe the early and late outcomes of the arterial switch for transposition.

METHODS

A single-centre retrospective cohort study was conducted to assess the early and late outcomes of arterial switch performed during infancy using a standardised institutional approach between 1988 and 2018, compared by morphological groups.

RESULTS

749 consecutive patients undergoing arterial switch during infancy were included, 464 (61.9%) with intact septum, 163 (21.8%) with isolated ventricular septal defect, and 122 (16.3%) with complex transposition with associated lesions, including 67 (8.9%) with Taussig-Bing anomaly. There were 34 early deaths (4.5%, 95% CI 3.1-6.1) with only 10 (2.6%) early deaths since 2000. Complex morphology (OR 11.44, CI 4.76-27.43) and intramural coronary artery (OR 5.17, CI 1.61-15.91) were identified as the most important risk factors for 90-day mortality. Overall survival was 92.7% (95% CI 90.8-94.6) at 5 years and 91.9% (95% CI 89.9-94.1) at 20 years; in hospital survivors, there were 15 (2.1%) late deaths during a median follow-up of 13.7 years. Cumulative incidence of surgical or catheter reintervention was 16.0% (95% CI 14.5-17.5) at 5 years and 22.7% (95% CI 21.0-24.0) at 20 years; early and late reinterventions were more common in the complex group, with no difference between the other groups.

CONCLUSIONS

Using a standardised approach, the arterial switch can be performed with low early mortality, moderate rates of reintervention, and excellent long-term survival. Concomitant lesions were the most important risk factor for early death and were associated with increased risk of late reintervention.

Training on Congenital 3D Cardiac Models - Will Models Improve Surgical Performance?

Technical skill development in congenital heart surgery (CHS) is challenging due to numerous factors which potentially limit the hands-on operative exposure in surgical training. These challenges have stimulated the growth of simulation-based training through the development of 3D-printed models, providing hands-on surgical training (HOST). From its inception in 2015, the models used in the HOST program have constantly improved, and now include valvar/subvalvar apparatus and better materials that mimic real tissue. Evidence shows that deliberate, regular simulation practice can improve a surgeon's technical skills across the spectrum of CHS. Furthermore, surgical trainees who undergo simulation training are able to translate this improved performance into the operative environment with improved patient outcomes. Despite evidence to support the incorporation of simulation methods into congenital training, its widespread adoption into training curricula remains low. This is due to numerous factors including funding, lack of dedicated time or proctorship and access to models-all of which can be overcome with the newer generation of models and committed trainers. Training programs should consider incorporating simulation-methods as a routine component of congenital training programs.

Quantification of lymphatic burden in patients with Fontan circulation by T2 MR lymphangiography and associations with adverse Fontan status

AIMS

To quantify thoracic lymphatic burden in paediatric Fontan patients using MRI and correlate with clinical status.

METHODS AND RESULTS

Paediatric Fontan patients (<18-years-old) with clinical cardiac MRI that had routine lymphatic 3D T2 fast spin echo (FSE) imaging performed from May 2017 to October 2019 were included. 'Lymphatic burden' was quantified by thresholding-based segmentation of the 3D T2 FSE maximum intensity projection image and indexed to body surface area, performed by two independent readers blinded to patient status. There were 48 patients (27 males) with median age at MRI of 12.9 (9.4-14.7) years, time from Fontan surgery to MRI of 9.1 (5.9-10.4) years, and follow-up time post-Fontan surgery of 9.4 (6.6-11.0) years. Intraclass correlation coefficient between two observers for lymphatic burden was 0.96 (0.94-0.98). Greater lymphatic burden correlated with post-Fontan operation hospital length of stay and duration of chest tube drainage (rs = 0.416, P = 0.004 and rs = 0.439, P = 0.002). Median lymphatic burden was greater in patients with chylous effusions immediately post-Fontan (178 (118-393) vs. 113 (46-190) mL/m2, P = 0.028), and in patients with composite adverse Fontan status (n = 13) defined by heart failure (n = 3), transplant assessment (n = 2), recurrent effusions (n = 6), Fontan thrombus (n = 2), and/or PLE (n = 6) post-Fontan (435 (137-822) vs. 114 (51-178) mL/m2, P = 0.003). Lymphatic burden > 600 mL/m2 was associated with late adverse Fontan status with sensitivity of 57% and specificity of 95%.

CONCLUSION

Quantification of MR lymphatic burden is a reliable tool to assess the lymphatics post-Fontan and is associated with clinical status.

The American Association for Thoracic Surgery (AATS) 2022 Expert Consensus Document: Management of infants and neonates with tetralogy of Fallot

OBJECTIVE

Despite decades of experience, aspects of the management of tetralogy of Fallot with pulmonary stenosis (TOF) remain controversial. Practitioners must consider newer, evolving treatment strategies with limited data to guide decision making. Therefore, the TOF Clinical Practice Standards Committee was commissioned by the American Association for Thoracic Surgery to provide a framework on this topic, focused on timing and types of interventions, management of high-risk patients, technical considerations during interventions, and best practices for assessment of outcomes of the interventions. In addition, the group was tasked with identifying pertinent research questions for future investigations. It is recognized that variability in institutional experience could influence the application of this framework to clinical practice.

METHODS

The TOF Clinical Practice Standards Committee is a multinational, multidisciplinary group of cardiologists and surgeons with expertise in TOF. With the assistance of a medical librarian, a citation search in PubMed, Embase, Scopus, and Web of Science was performed using key words related to TOF and its management; the search was restricted to the English language and the year 2000 or later. Articles pertaining to pulmonary atresia, absent pulmonary valve, atrioventricular septal defects, and adult patients with TOF were excluded, as well as nonprimary sources such as review articles. This yielded nearly 20,000 results, of which 163 were included. Greater consideration was given to more recent studies, larger studies, and those using comparison groups with randomization or propensity score matching. Expert consensus statements with class of recommendation and level of evidence were developed using a modified Delphi method, requiring 80% of the member votes with 75% agreement on each statement.

RESULTS

In asymptomatic infants, complete surgical correction between age 3 and 6 months is reasonable to reduce the length of stay, rate of adverse events, and need for a transannular patch. In the majority of symptomatic neonates, both palliation and primary complete surgical correction are useful treatment options. It is reasonable to consider those with low birth weight or prematurity, small or discontinuous pulmonary arteries, chromosomal anomalies, other congenital anomalies, or other comorbidities such as intracranial hemorrhage, sepsis, or other end-organ compromise as high-risk patients. In these high-risk patients, palliation may be preferred; and, in patients with amenable anatomy, catheter-based procedures may prove favorable over surgical palliation.

CONCLUSIONS

Ongoing research will provide further insight into the role of catheter-based interventions. For complete surgical correction, both transatrial and transventricular approaches are effective; however, the smallest possible ventriculotomy should be utilized. When possible, the pulmonary valve should be spared; and if unsalvageable, reconstruction can be considered. At the conclusion of the operation, adequate relief of the right ventricular outflow obstruction should be confirmed, and identification of a significant fixed anatomical obstruction should prompt further intervention. Given our current knowledge and the gaps identified, we propose several key questions to be answered by future research and potentially by a TOF registry: When to palliate or proceed with complete surgical correction, as well as the ideal type of palliation; the optimal surgical approach for complete repair for the best long-term preservation of right ventricular function; and the utility, efficacy, and durability of various pulmonary valve preservation and reconstruction techniques.

Congenital Heart Surgery Skill Training Using Simulation Models: Not an Option but a Necessity

Congenital heart surgery (CHS) is technically demanding, and its training is extremely complex and challenging. Training of the surgeon's technical skills has relied on a preceptorship format in which the trainees are gradually exposed to patients in the operating room under the close tutelage of senior staff surgeons. Training in the operating room is an inefficient process and the concept of a learning curve is no longer acceptable in terms of patient outcomes. The benefits of surgical simulation in training of congenital heart surgeons are well known and appreciated. However, adequate surgical simulation models and equipment for training have been scarce until the recent development of three-dimensionally (3D) printed models. Using comprehensive 3D printing and silicone-molding techniques, realistic simulation training models for most congenital heart surgical procedures have been produced. Newly developed silicone-molded models allow efficient CHS training in a stress-free environment with instantaneous feedback from the proctors and avoids risk to patients. The time has arrived when all congenital heart surgeons should consider surgical simulation training before progressing to real-life operating in a similar fashion to the aviation industry where all pilots are required to complete simulation training before flying a real aircraft. It is argued here that simulation training is not an option anymore but should be a mandatory component of CHS training.

Growth of unrepaired hypoplastic proximal aortic arch and reintervention rate after aortic coarctation repair

BACKGROUND

Treatment of tubular hypoplasia of the aortic arch (THAA) associated with aortic coarctation (CoA) remains controversial. We aimed to evaluate growth of unrepaired hypoplastic proximal aortic arches (PAAs) after surgical repair for CoA.

METHODS

Preoperative and follow-up echocardiographic images of 139 patients who underwent CoA repairs from 2005 to 2012 were reviewed. THAA was defined as PAA z-score <-3 and non-THAA group z-score ≥-3. Reintervention rates due to aortic obstruction were assessed using competing risk models and diameters of the aorta were compared with Mann-Whitney U tests.

RESULTS

Fifty patients (36%) had THAA and 89 (64%) had non-THAA. The survival rate was 94% at 10 years. The overall reintervention rate at 10 years was 9% in the THAA group and 16% in the non-THAA group (P = .54). The catheter reintervention rate at ten years was 2% in the THAA group and 16% in the non-THAA group (P = .031). The surgical reintervention rate at ten years was 7% in the THAA group and 0% in the non-THAA group (P = .016). All 4 patients who required surgical reintervention were in the THAA group and 3 patients with PAA obstruction had preoperative PAA z-scores -3.6, -4.2, and -4.3. Follow-up echocardiograms showed PAA catch-up growth in the THAA group compared with the non-THAA group (preoperative z-score of -3.6 vs -2.3, and at 7 years of -1.1 vs -1.2; P < .001).

CONCLUSIONS

Unrepaired PAA hypoplasia grows after CoA repair. Reintervention rates were comparable between groups but those with THAA had higher surgical reintervention rates.

Aortic Atresia or Complex Left Outflow Tract Obstruction in the Presence of a Ventricular Septal Defect

Severe left outflow tract obstruction (LVOTO) is not always associated with hypoplastic left heart syndrome (HLHS). Aortic valvar atresia or complex LVOTO in the presence of a large ventricular septal defect (VSD) are a rare group of lesions that offer the possibility of biventricular repair. The Yasui procedure is the commonest surgical approach which can be performed as a primary neonatal correction or as a staged procedure with a Norwood followed by a subsequent Rastelli. This article reviews the surgical outcomes and decision-making process. Both strategies are reasonable with the trend toward staged procedure in the setting of the additional interrupted arch, with neonatal survival of > 90% in the modern era and excellent long-term survival. Re-intervention is mostly related to conduit revision and the need for re-operation for LVOTO is rare. Deciding between conventional repair and the Yasui in cases of LVOTO/VSD can be difficult and there are no uniform accepted criteria. In a typical neonate, an aortic annulus < 4.5 mm is generally the limit of acceptability for a conventional repair. In selected cases of LVOTO/VSD, an alternative to the Yasui is the Ross-Konno. Retrospective comparisons between the 2 techniques are difficult due to differing patient characteristics (especially associated with mitral valve disease) but the neonatal Ross has been associated with higher early mortality.

Non-invasive cardiac output monitoring with electrical velocimetry after cardiac surgery in infants

INTRODUCTION

Low cardiac output following cardiac surgery is a major determinant of outcome that may be improved by early detection, yet there are no widely accepted methods for its measurement in young children. We evaluated the feasibility of the routine use of electrical velocimetry, a non-invasive technique providing continuous measurement of cardiac output, in infants in the early postoperative period.

METHODS

With ethical approval and parental consent, infants undergoing cardiac surgery were recruited. The ICON electrical velocimetry monitor was attached on admission to the intensive care unit (ICU) and remained for up to 24h.

RESULTS

A total of 15 infants were recruited, median age 3 months (interquartile range (IQR) 0.5-7.5) and weight 4.8kg (IQR 3.9-7.1), undergoing various operations. Cardiac index had a weak correlation with arterial lactate (r=-0.24, p=0.02) and no correlation with blood pressure, central venous pressure or arteriovenous oxygen difference. Data were recorded for a median of 19h (range 5-24), with lead detachment or movement artefact the most common causes of data loss. There was marked minute-to-minute variability, with 25% of consecutive measurements having >5% variability.

CONCLUSION

Cardiac index measured by electrical velocimetry in infants in the early postoperative period is impaired by frequent data loss and marked intrapatient variability. Our feasibility study suggests that it is unsuitable for use as a routine monitoring tool in the setting of postsurgical ICU care.

Canadian Cardiovascular Society 2022 Guidelines for Cardiovascular Interventions in Adults With Congenital Heart Disease

Interventions in adults with congenital heart disease (ACHD) focus on surgical and percutaneous interventions in light of rapidly evolving ACHD clinical practice. To bring rigour to our process and amplify the cumulative nature of evidence ACHD care we used the ADAPTE process; we systematically adjudicated, updated, and adapted existing guidelines by Canadian, American, and European cardiac societies from 2010 to 2020. We applied this to interventions related to right and left ventricular outflow obstruction, tetralogy of Fallot, coarctation, aortopathy associated with bicuspid aortic valve, atrioventricular canal defects, Ebstein anomaly, complete and congenitally corrected transposition, and patients with the Fontan operation. In addition to tables indexed to evidence, clinical flow diagrams are included for each lesion to facilitate a practical approach to clinical decision-making. Excluded are recommendations for pacemakers, defibrillators, and arrhythmia-directed interventions covered in separate designated documents. Similarly, where overlap occurs with other guidelines for valvular interventions, reference is made to parallel publications. There is a paucity of high-level quality of evidence in the form of randomized clinical trials to support guidelines in ACHD. We accounted for this in the wording of the strength of recommendations put forth by our national and international experts. As data grow on long-term follow-up, we expect that the evidence driving clinical practice will become increasingly granular. These recommendations are meant to be used to guide dialogue between clinicians, interventional cardiologists, surgeons, and patients making complex decisions relative to ACHD interventions.

Improving coronary ultrafast Doppler angiography using fractional moving blood volume and motion-adaptive ensemble length

Coronary microperfusion assessment is a key parameter for understanding cardiac function. Currently, coronary ultrafast Doppler angiography is the only non-invasive clinical imaging technique able to assess coronary microcirculation quantitatively in humans. In this study, we propose to use fractional moving blood volume (FMBV), proportional to the red blood cell concentration, as a metric for perfusion. FMBV compares the power Doppler in a region of interest (ROI) inside the myocardium to the power Doppler of a reference area in the heart chamber, fully filled with blood. This normalization gives then relative values of the ROI blood filling. However, due to the impact of ultrasound attenuation and elevation focus on power Doppler values, the reference area and the ROI need to be at the same depth to allow this normalization. This condition is rarely satisfied in vivo due to the cardiac anatomy. Hereby, we propose to locally compensate the attenuation between the ROI and the reference, by measuring the attenuation law on a phantom. We quantified the efficiency of this approach by comparing FMBV with and without compensation on a flow phantom. Compensated FMBV was able to estimate the ground-truth FMBV with less than 5% variation. This method was then adapted to the in vivo case of myocardial perfusion imaging during heart surgery on human neonates. The translation from in vitro to in vivo required an additional clutter filtering step to ensure that blood signals could be correctly identified in the fast-moving myocardium. We applied the singular value decomposition filter on temporal sliding windows whose lengths were a function of myocardium motion. This motion-adaptive temporal sliding window approach was able to improve blood and tissue separation in terms of contrast-to-noise ratio, as compared to well-established constant-length sliding window approaches. Therefore, compensated FMBV and singular value decomposition assisted with motion-adaptive temporal sliding windows improves the quantification of blood volume in coronary ultrafast Doppler angiography.

Familial Recurrence Patterns in Congenitally Corrected Transposition of the Great Arteries: An International Study

BACKGROUND

Congenitally corrected transposition of the great arteries (ccTGA) is a rare disease of unknown cause. We aimed to better understand familial recurrence patterns.

METHODS

An international, multicentre, retrospective cohort study was conducted in 29 tertiary hospitals in 6 countries between 1990 and 2018, entailing investigation of 1043 unrelated ccTGA probands.

RESULTS

Laterality defects and atrioventricular block at diagnosis were observed in 29.9% and 9.3%, respectively. ccTGA was associated with primary ciliary dyskinesia in 11 patients. Parental consanguinity was noted in 3.4% cases. A congenital heart defect was diagnosed in 81 relatives from 69 families, 58% of them being first-degree relatives, including 28 siblings. The most prevalent defects in relatives were dextro-transposition of the great arteries (28.4%), laterality defects (13.6%), and ccTGA (11.1%); 36 new familial clusters were described, including 8 pedigrees with concordant familial aggregation of ccTGA, 19 pedigrees with familial co-segregation of ccTGA and dextro-transposition of the great arteries, and 9 familial co-segregation of ccTGA and laterality defects. In one family co-segregation of ccTGA, dextro-transposition of the great arteries and heterotaxy syndrome in 3 distinct relatives was found. In another family, twins both displayed ccTGA and primary ciliary dyskinesia.

CONCLUSIONS

ccTGA is not always a sporadic congenital heart defect. Familial clusters as well as evidence of an association between ccTGA, dextro-transposition of the great arteries, laterality defects and in some cases primary ciliary dyskinesia, strongly suggest a common pathogenetic pathway involving laterality genes in the pathophysiology of ccTGA.

Association of atrial septal fenestration with outcomes after atrioventricular septal defect repair

OBJECTIVE

During repair of atrioventricular septal defect (AVSD), surgeons might leave an atrial level shunt when concerned about postoperative physiology, or as part of routine practice. However, the association of fenestration with outcomes is unclear. We sought to determine factors associated with mortality after biventricular repair of AVSD.

METHODS

We included 581 patients enrolled from 32 Congenital Heart Surgeons' Society institutions from January 1, 2012, to June 1, 2020 in the Congenital Heart Surgeons' Society AVSD cohort. Parametric multiphase hazard analysis was used to identify factors associated with mortality. A random effect model was used to account for possible intersite variability in mortality.

RESULTS

An atrial fenestration was placed during repair in 133/581 (23%) patients. Overall 5-year survival after repair was 91%. Patients who had fenestration had an 83% 5-year survival versus 93% for those not fenestrated (P < .001). Variables associated with mortality in multivariable hazard analysis included institutional diagnosis of ventricular unbalance (hazard ratio [HR], 2.7 [95% confidence interval (CI): 1.5-4.9]; P = .003), preoperative mechanical ventilation (HR, 4.1 [95% CI, 1.3-13.1]; P = .02), atrial fenestration (HR, 2.8 [95% CI, 1.5-4.9]; P < .001), and reoperation for ventricular septal defect (HR, 4.0 [95% CI, 1.3-13.1]; P = .002). There was no difference in measures of ventricular unbalance for comparisons of fenestrated with nonfenestrated patients. No significant interinstitution variability in mortality was observed on the basis of the random effect model (P = .7).

CONCLUSIONS

An atrial communication at biventricular repair of AVSD is associated with significantly reduced long-term survival after adjusting for other known associated factors, including unbalance. These findings might challenge the routine practice of fenestration.

Supravalvular aortic stenosis repair: surgical training of 2 repair techniques using 3D-printed models

There are a number of techniques used in the surgical treatment of supravalvular aortic stenosis with excellent results; however, junior surgeons' experience may be limited due to its rare nature. Simulation with 3D-printed models provides a safe platform for surgeons to rehearse surgical techniques prior to patient application but must replicate all features of surgical anatomy. Here, we describe how software manipulation can be used to accurately reproduce the surgical anatomy in supravalvular aortic stenosis and be used to train surgeons in 2 different techniques.

Current Status of Training and Certification for Congenital Heart Surgery Around the World: Proceedings of the Meetings of the Global Council on Education for Congenital Heart Surgery of the World Society for Pediatric and Congenital Heart Surgery

The optimal training of the highly specialized congenital heart surgeon is a long and complex process, which is a significant challenge in most parts of the world. The World Society for Pediatric and Congenital Heart Surgery (WSPCHS) has established the Global Council on Education for Congenital Heart Surgery as a nonprofit organization with the goal of assessing current training and certification and ultimately establishing standardized criteria for the training, evaluation, and certification of congenital heart surgeons around the world. The Global Council and the WSPCHS have reviewed the present status of training and certification for congenital cardiac surgery around the world. There is currently lack of consensus and standardized criteria for training in congenital heart surgery, with significant disparity between continents and countries. This represents significant obstacles to international job mobility of competent congenital heart surgeons and to the efforts to improve the quality of care for patients with Congenital Heart Disease worldwide. The purpose of this article is to summarize and document the present state of training and certification in congenital heart surgery around the world.

Factors associated with mortality or transplantation versus Fontan completion after cavopulmonary shunt for patients with tricuspid atresia

OBJECTIVE

Tricuspid atresia with normally related great vessels (TA) is considered the optimal substrate for the Fontan pathway. The factors associated with death or transplantation after cavopulmonary shunt (CPS) are underappreciated. We aimed to determine factors associated with CPS-Fontan interstage death/transplantation versus transition to Fontan in TA.

METHODS

A total of 417 infants younger than 3 months of age with TA were enrolled (January 1999 to February 2020) from 40 institutions into the Congenital Heart Surgeons' Society TA cohort. Parametric competing risk methodology was used to determine factors associated with the competing end points of death/transplantation without Fontan completion, and transition to Fontan.

RESULTS

CPS was performed in 382 patients with TA; of those, 5% died or underwent transplantation without transition to Fontan and 91% transitioned to Fontan by 5 years after CPS. Prenatal diagnosis (hazard ratio [HR], 0.74; P < .001) and pulmonary artery band (PAB) at CPS (HR, 0.50; P < .001) were negatively associated with Fontan completion. Preoperative moderate or greater mitral valve regurgitation (HR, 3.0; P < .001), concomitant mitral valve repair (HR, 11.0; P < .001), PAB at CPS (HR, 3.0; P < .001), postoperative superior vena cava interventions (HR, 9.0; P < .001), and CPS takedown (HR, 40.0; P < .001) were associated with death/transplantation.

CONCLUSIONS

The mortality rate after CPS in patients with TA is notable. Those with preoperative mitral valve regurgitation remain a high-risk group. PAB at the time of CPS being associated with both increased risk of death and decreased Fontan completion may represent a deleterious effect of antegrade pulmonary blood flow in the CPS circulation.

Four right ventricle to pulmonary artery conduit types

OBJECTIVE

The most durable valved right ventricle to pulmonary artery conduit for the repair of congenital heart defects in patients of different ages, sizes, and anatomic substrate remains uncertain.

METHODS

We performed a retrospective analysis of 4 common right ventricle to pulmonary artery conduits used in a single institution over 30 years, using univariable and multivariable models of time-to-failure to analyse freedom from conduit dysfunction, reintervention, and replacement.

RESULTS

Between 1988 and 2018, 959 right ventricle to pulmonary artery conduits were implanted: 333 aortic homografts, 227 pulmonary homografts, 227 composite porcine valve conduits, and 172 bovine jugular vein conduits. Patients weighed 1.6 to 98.3 kg (median 15.3 kg), and median duration of follow-up was 11.4 years, with 505 (52.2%) conduits developing dysfunction, 165 (17.2%) requiring catheter intervention, and 415 (43.2%) being replaced. Greater patient weight, conduit z-score, type and position, as well as catheter intervention were predictors of freedom from replacement. Multivariable analysis demonstrated inferior durability for smaller composite porcine valve conduits, with excellent durability for larger diameter conduits of the same type. Bovine jugular vein conduit longevity was inferior to that of homografts in all but the smallest patients. Freedom from dysfunction at 8 years was 60.7% for aortic homografts, 72% for pulmonary homografts, 51.2% for composite porcine valve conduits, and 41.3% for bovine jugular vein conduits. Judicious oversizing of the conduit improved conduit durability in all patients, but to the greatest extent in patients weighing 5 to 20 kg.

CONCLUSIONS

Pulmonary and aortic homografts had greater durability than xenograft conduits, particularly in patients weighing 5 to 20 kg. Judicious oversizing was the most significant surgeon-modifiable factor affecting conduit longevity.

How and When Should Tetralogy of Fallot be Palliated Prior to Complete Repair?

The controversy regarding the best or ideal surgical management of Tetralogy of Fallot (ToF) stems from the recognition of there being a spectrum of morphology and associated lesions, each of which require a different approach to achieve the three goals of minimizing mortality preserving right ventricular function long-term and minimizing reinterventions. A one-size-fits-all approach to ToF needs to be replaced by a considered and personalized approach in order to yield the best outcomes possible for individual patients. The great majority of patients with ToF undergo primary complete repair between age 3-9 months with excellent outcomes. However, the greatest challenge is the severely cyanotic neonates where primary repair is still associated with high mortality and reintervention rates. Risk factors are low weight and small/poorly developed pulmonary vasculature. High-risk neonates have better outcomes with palliation-but mortality is still high. Palliative interventions in the catherization lab are showing better outcomes than traditional BT shunt and the RVOT stent is emerging as potential game-changer. Primary neonatal repair is still recommended if weight >3 kg and Nakata >100 mm²/m². However, neonates with low weight, small pulmonary arteries or multiple comorbidities (including ToF/AVSD and anomalous LAD) may do better with a staged approach, There is good argument for RVOT stenting as a bridge to complete repair due to its stable circulation without diastolic run off and volume loading of the circulation, and its potential to allow branch PA growth.

The Incorporation of Hands-On Surgical Training in a Congenital Heart Surgery Training Curriculum

BACKGROUND

The monthly in-house Hands-On Surgical Training (HOST) program was incorporated into the congenital heart surgery (CHS) curriculum for surgical trainees within our institution. This study evaluated whether there was an improvement and retention of technical skills throughout the curriculum via objective assessment methods.

METHODS

Twelve 3-dimensional-printed surgical heart models were included into the year-long curriculum. The monthly sessions were attended by all trainees and staff surgeons. Proctors demonstrated the operation on a model, which was followed by 2 attempts by each trainee. Attempts were recorded for objective assessment. On completion of the curriculum trainees repeated 4 procedures an additional 2 times after a delay to assess skill retention.

RESULTS

Twelve sessions were completed by 7 trainees within the curriculum. Objective assessments were performed in 7 sessions. Eighty-one percent of trainees' scores improved between the 2 attempts, with a mean improvement of 13% (attempt 1: HOST-CHS score of 79, attempt 2: HOST-CHS score of 89; P < .001). Similarly, 91% of procedural times improved by a mean of 25% (attempt 1, 1:22:00 [hours:minutes:seconds]; attempt 2, 1:01:21; P < .001). During individual procedure analysis, statistical significance remained in 3 of 7 procedures (P < .05). Four procedures were assessed for skill retention after a delay (2-14 months). Scores decreased by 4% in 47% of trainees during attempt 3 (attempt 2: HOST-CHS score of 94, attempt 3: HOST-CHS score of 91; P = .34) but improved in 79% during attempt 4 (attempt 3: HOST-CHS score of 91, attempt 4: HOST-CHS score of 99; P = .004), matching their previous performance.

CONCLUSIONS

The monthly HOST course was successfully incorporated into a training curriculum for CHS surgeons using objective assessments to measure technical performance. Trainees demonstrated an improvement across all evaluated procedures and retained their skills when reassessed after a delay highlighting its value in CHS training.

Assessment tool validation and technical skill improvement in the simulation of the Norwood operation using three-dimensional-printed heart models

OBJECTIVES

The hands-on surgical training course utilizes 3-dimensional (3D)-printed heart models to simulate complex congenital heart operations. This study aimed to validate a model and assessment tool in the simulation of 2 techniques of the Norwood operation and investigate whether technical performance improves following rehearsal with or without proctor presence.

METHODS

Five 'experienced' and 5 'junior' surgeons performed 2 techniques of the Norwood operation on 3D-printed models of hypoplastic left heart syndrome. Performances were retrospectively assessed by 10 raters with varying experience in congenital heart surgery (CHS) (Medical Doctorate versus non-Medical Doctorate). Assessments were made with the procedure-specific Hands-On Surgical Training-CHS tool. Results were analysed for technical performance and rater consistency. Following validation, 30 surgeons (24 with proctor guidance and 6 with training videos and objective feedback only) simulated the Norwood operation twice.

RESULTS

Performance scores were consistently higher for experienced surgeons and raters discriminated clearly between the experienced and junior surgeons (P ≤ 0.001). The hands-on surgical training-CHS tool showed high inter-rater (0.86) and intra-rater (0.80) reliability among all raters. Scores for both experienced and junior surgeons were highly consistent across all raters, with no statistically significant difference (P = 0.50). All surgeons successfully performed the Norwood operation. Sixty attempts were scored in total. Eighty-seven percentage (26/30) of surgeons' scores (mean: attempt 1 = 92, attempt 2 = 104) and times [mean: attempt 1 = 1:22:00, attempt 2 = 1:08:00 (h:mm:ss)] improved between the 2 attempts by 9% and 15% respectively (P ≤ 0.001). Total scores of all surgeons in the non-proctored subgroup (6) improved by 15% on average (mean: attempt 1 = 86, attempt 2 = 105, P = 0.002).

CONCLUSIONS

Procedure-specific assessment tools can be developed to evaluate technical performance for complex CHS simulation and be performed reliably by non-expert raters. Rehearsal both under supervision and independently leads to technical skill improvement further supporting its value in CHS training.

Factors associated with unplanned reinterventions and their relation to early mortality after pediatric cardiac surgery

OBJECTIVE

Unplanned reintervention (uRE) is used as an indicator of patient morbidity and quality of care in pediatric cardiac surgery. We investigated associated factors and early mortality after uREs.

METHODS

Morbidity data were prospectively collected in 5 UK centers between 2015 and 2017; uRE included surgical cardiac, interventional transcatheter cardiac, permanent pacemaker, and diaphragm plication procedures. Mortality (30-day and 6-month) in uRE/no-uRE patients was reported before and after matching. Predicted 30-day mortality was calculated using the Partial Risk Adjustment in Surgery score.

RESULTS

A total of 3090 procedures (2861 patients) were included (median age, 228 days). There were 146 uREs, resulting in an uRE rate of 4.7%. Partial Risk Adjustment in Surgery score, 30-day mortality and 6-month mortality in uRE and no-uRE groups were 2.4% versus 1.3%, 8.9% versus 1%, and 17.1% versus 2.4%, respectively. After matching, mortality at 6 months remained higher in uRE compared with no-uRE (12.2% vs 1.4%; P = .02; 74 pairs). In the uRE group, 21 out of 25 deaths at 6 months occurred when at least 1 additional postoperative complication was present. In multivariable analysis, neonatal age (P = .002), low weight (P = .009), univentricular heart (P < .001), and arterial shunt (P < .001) were associated with increased risk of uRE, but Partial Risk Adjustment in Surgery score was not (only in univariable analysis).

CONCLUSIONS

uREs are a relatively frequent complication after pediatric cardiac surgery and are associated with some patient characteristics, but not the Partial Risk Adjustment in Surgery risk score. Early mortality was higher after uRE, independent of preoperative factors, but linked to other postoperative complications.

Unifocalization cannot rely exclusively on native pulmonary arteries: the importance of recruitment of major aortopulmonary collaterals in 249 cases†

OBJECTIVES

We sought to define the early and late outcomes of unifocalization based on a classification of the native pulmonary artery (nPA) system and major aortopulmonary collateral arteries (MAPCAs) with a policy of combined recruitment and rehabilitation and to analyse the role of unifocalization by leaving the ventricular septal defect (VSD) open with a limiting right ventricle-pulmonary artery (RV-PA) conduit in borderline cases.

METHODS

An analysis of 271 consecutive patients assessed for unifocalization at a single institution between 1988 and 2016 was performed. Patients were classified according to the pulmonary blood supply: group A, unifocalization based on nPA only; group B, based on nPA and MAPCAs; group C, MAPCAs only (absent nPAs).

RESULTS

Unifocalization was achieved in 249 (91.9%) cases with an early mortality of 2.8%. Group A included 72 (28.9%) patients, group B 119 (47.8%) patients and group C 58 (23.3%) patients with no difference in early survival between groups. Survival at 5, 10 and 15 years was 90.0% (85.9-94.3), 87.2% (83.5-91.2) and 82.3% (75.2-89.9), respectively. Late survival in groups A and B was similar but 10- and 15-year survival in group C decreased to 79.2% (68.2-92.1) and 74.3% (61.1-90.4) (P = 0.02), respectively. A mean of 1.9 (±0.6) MAPCAs were recruited per patient (range 0-6). The VSD was left open with a limiting RV-PA conduit in 97 (39.0%) cases, but subsequently closed in 48 patients, giving a total of 200 (80.3%) patients achieving VSD closure (full repair). Delaying VSD closure was not associated with increased risk for early or late survival. A central shunt to rehabilitate the nPAs was used in 56 (22.5%) cases. This was associated with a reduction in the number of MAPCAs recruited, but still required a mean of 1.8 (±0.5) MAPCAs recruited per patient to achieve unifocalization. In multivariate risk analysis, those suitable for single-stage full repair had the best long-term outcomes. Group C anatomy was associated with poor late survival compared to groups A and B (hazard ratio 2.7).

CONCLUSIONS

Survival is maximized by a combined approach of rehabilitation and recruitment. MAPCAs should always be recruited if they supply areas with absent nPA supply. A strategy of leaving the VSD open with a limiting RV-PA conduit is a safe and effective way of managing borderline cases.