The Society of Thoracic Surgeons Congenital Heart Surgery Database: 2023 Update on Outcomes and Research.

The Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database (CHSD) continues to be the most comprehensive database of congenital and pediatric cardiothoracic surgical procedures in the world and contains information on 664,210 operations as of June 30, 2023. The 35th harvest of the STS CHSD data was undertaken in Spring 2023, spanning the 4-year period January 1, 2019, through December 31, 2022, and included 144,919 operations performed at 114 participating sites in North America. The harvest analysis was successfully executed by the STS Research and Analytic Center. The overall unadjusted mortality rate was 2.68% and has remained stable over the 4 years included in the current harvest window. Mortality is highest in neonates (7.4%) and lowest in children (1.1%). As in prior analyses, observed mortality and postoperative length of stay in the database increase with an increase in STS-European Association for Cardio-Thoracic Surgery (STAT) Congenital Heart Surgery Mortality Categories. This quality report summarizes contemporary outcomes, provides the odds ratios for the CHSD risk model variables based on this analysis, and describes on-going efforts to improve data collection and augment analytical approaches. Lastly, 5 research publications completed in the last year using data from the CHSD are also summarized.

From Surgical to Total Transcatheter Stage I Palliation: Exploring Evidence and Perspectives.

Neonates with single ventricle physiology and ductal-dependent systemic circulation, such as those with hypoplastic left heart syndrome, undergo palliation in the first days of life. Over the past decades, variations on the traditional Stage 1 palliation, also known as Norwood operation, have emerged. These include the hybrid palliation and the total transcatheter approach. Here, we review the current evidence and data on different Stage 1 approaches, with a focus on their advantages, challenges, and future perspectives. Overall, although controversy remains regarding the superiority or inferiority of one approach to another, outcomes after the Norwood and the hybrid palliation have improved over time. However, both procedures still represent high-risk approaches that entail exposure to sternotomy, surgery, and potential cardiopulmonary bypass. The total transcatheter Stage 1 palliation spares patients the surgical and cardiopulmonary bypass insults and has proven to be an effective strategy to bridge even high-risk infants to a later palliative surgery, complete repair, or transplant. As the most recently proposed approach, data are still limited but promising. Future studies will be needed to better define the advantages, challenges, outcomes, and overall potential of this novel approach.

Single Ventricular Assist Device Care and Outcomes for Failed Stage I Palliation: A Single-Center Decade of Experience.

Single ventricular assist device (SVAD) use before and after stage I palliation (S1P) is increasing with limited data on outcomes. To address this knowledge gap, we conducted a single-center retrospective review to assess pre- and post-SVAD clinical status, complications, and outcomes. We leveraged a granular, longitudinal, local database that captures end-organ support, procedural interventions, hematologic events, laboratory data, and antithrombotic strategy. We identified 25 patients between 2013 and 2023 implanted at median age of 53 days (interquartile range [IQR] = 16-130); 80% had systemic right ventricles and underwent S1P. Median SVAD days were 54 (IQR = 29-86), and 40% were implanted directly from ECMO. Compared to preimplant, there was a significant reduction in inotrope use ( p = 0.013) and improved weight gain ( p = 0.008) post-SVAD. Complications were frequent including bleeding (80%), stroke (40%), acute kidney injury (AKI) (40%), infection (36%), and unanticipated catheterization (56%). Patients with in-hospital mortality had significantly more bleeding complications ( p = 0.02) and were more likely to have had Blalock-Thomas-Taussig shunts pre-SVAD ( p = 0.028). Survival to 1 year postexplant was 40% and included three recovered and explanted patients. At 1 year posttransplant, all survivors have technology dependence or neurologic injury. This study highlights the clinical outcomes and ongoing support required for successful SVAD use in failed single-ventricle physiology before or after S1P.

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.

Outcomes of the Kawashima: A Society of Thoracic Surgeons Congenital Heart Surgery Database Analysis.

BACKGROUND: We aimed to evaluate the effect of age at operation on postoperative outcomes in children undergoing a Kawashima operation. METHODS: The Society of Thoracic Surgeons Congenital Heart Surgery Database was queried for Kawashima procedures from January 1, 2014, to June 30, 2020. Patients were stratified by age at operation in months: 0 to <4, 4 to <8, 8 to <12, and >12. Subsequently, outcomes for those in whom the Kawashima was not the index operation and for those undergoing hepatic vein incorporation (Fontan completion or hepatic vein-to-azygos vein connection) were evaluated. RESULTS: We identified 253 patients who underwent a Kawashima operation (median age, 8.6 months; median weight, 7.4 kg): 12 (4.7%), 0 to <4 months; 96 (37.9%), 4 to <8 months; 81 (32.0%), 8 to <12 months; and 64 (25.3%), >12 months. Operative mortality was 0.8% (n = 2), with major morbidity or mortality in 17.4% (n = 44), neither different across age groups. Patients <4 months had a longer postoperative length of stay (12.5 vs 9.3 days; P = .03). The Kawashima was not the index operation of the hospital admission in 15 (5.9%); these patients were younger (6.0 vs 8.4 months; P = .05) and had more preoperative risk factors (13/15 [92.9%] vs 126/238 [52.9%]; P < .01). We identified 173 patients undergoing subsequent hepatic vein incorporation (median age, 3.9 years; median weight, 15.0 kg) with operative mortality in 6 (3.5%) and major morbidity or mortality in 30 (17.3%). CONCLUSIONS: The Kawashima is typically performed between 4 and 12 months with low mortality. Morbidity and mortality were not affected by age. Hepatic vein incorporations may be higher risk than in traditional Fontan procedures, and ways to mitigate this should be sought.

Lung Re-transplantation after prolonged veno-venous extracorporeal membrane oxygenation (ECMO) in a child with chronic lung allograft dysfunction.

BACKGROUND: Extracorporeal Membrane Oxygenation (ECMO) may be used as a bridge to lung transplantation in selected patients with end-stage respiratory failure. Historically, ECMO use in this setting has been associated with poor outcomes Puri V et.al, J Thorac Cardiovasc Surg, 140:427. More recently, technical advances and the implementation of rehabilitation and ambulation while awaiting transplantation on ECMO have led to improved surgical and post-transplant outcomes Kirkby S et.al, J Thorac Dis, 6:1024. METHODS: We illustrate the case of a 6-year-old child who received prolonged ECMO support as a bridge to lung re-transplantation secondary to Chronic Lung Allograft Dysfunction (CLAD). RESULTS: Early rehabilitation was key in improving the overall pre-transplant conditioning during ECMO. CONCLUSIONS: Despite challenges associated with awake/ambulatory ECMO, the use of this strategy as a bridge to lung transplantation is feasible and has resulted in improved pre-transplant conditioning and post-transplant outcomes.

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.

Hypoplastic Left Heart Syndrome With Low Birth Weight or Prematurity: What Is the Optimal Approach?

BACKGROUND: Hypoplastic left heart syndrome with low birth weight or prematurity comprises a high-risk population with no optimal treatment pathway. Using the Pediatric Health Information System, we compared management approaches across the United States. METHODS: We analyzed neonates (≤30 days) with birth weight <2500 grams or gestational age <36 weeks between 2012 and 2021. Four strategies were identified: Norwood procedure, ductus arteriosus stent + pulmonary artery banding, pulmonary artery banding + prostaglandin infusion, or comfort care. Outcomes included hospital survival, discharge disposition, staged palliation completion, and 1-year transplant-free survival. RESULTS: Of 383 infants identified, 36.4% (n = 134) received comfort care, 43.9% (n = 165) Norwood, 12.4% (n = 49) ductal stent + pulmonary artery bands, and 8.8% (n = 34) pulmonary artery bands + prostaglandins. Neonates receiving comfort care had the lowest gestational age (35 weeks; interquartile range [IQR], 31.5-37 weeks) and birth weight (2.0 kg; IQR, 1.5-2.3 kg); 24.6% (33 of 134) had chromosomal anomalies. Infants undergoing primary Norwood had the highest birth weight (2.4 kg; IQR, 2.2-2.5 kg) and gestational age (37 weeks; IQR, 35-38 weeks). Glenn palliation was performed in 66.1% (109 of 165) compared with ductal stent + pulmonary artery band in 18.4% (9 of 49) and pulmonary artery band + prostaglandins in 35.3% (12 of 34). Only 11.3% (6 of 53) born <2 kg survived to 1 year, all after Norwood. Primary Norwood yielded higher hospital and 1-year transplant-free survival than hybrid strategies. CONCLUSIONS: Comfort care is routinely provided, particularly for infants with low birth weight, gestational age, or chromosomal anomalies. Primary Norwood offered the lowest hospital and 1-year mortality and highest palliation completion rates; birth weight was the most important factor determining 1-year survival.

Characteristics of donor lungs declined on site and impact of lung allocation policy change.

OBJECTIVE: National and institutional data suggest an increase in organ discard rate (donor lungs procured but not implanted) after a new lung allocation policy was introduced in 2017. However, this measure does not include on-site decline rate (donor lungs declined intraoperatively). The objective of this study is to examine the impact of the allocation policy change on on-site decline. METHODS: We used a Washington University (WU) and our local organ procurement organization (Mid-America Transplant [MTS]) database to abstract data on all accepted lung offers from 2014 to 2021. An on-site decline was defined as an event in which the procuring team declined the organs intraoperatively, and the lungs were not procured. Logistic regression models were used to investigate potentially modifiable reasons for decline. RESULTS: The overall study cohort comprised 876 accepted lung offers, of which 471 donors were at MTS with WU or others as the accepting center and 405 at other organ procurement organizations with WU as the accepting center. At MTS, the on-site decline rate increased from 4.6% to 10.8% (P = .01) after the policy change. Given the greater likelihood of non-local organ placement and longer travel distance after policy change, the estimated cost of each on-site decline increased from $5727 to $9700. In the overall group, latest partial pressure of oxygen (odds ratio [OR], 0.993; 95% confidence interval [CI], 0.989-0.997), chest trauma (OR, 2.474; CI, 1.018-6.010), chest radiograph abnormality (OR, 2.902; CI, 1.289-6.532), and bronchoscopy abnormality (OR, 3.654; CI, 1.813-7.365) were associated with on-site decline, although lung allocation policy era was unassociated (P = .22). CONCLUSIONS: We found that nearly 8% of accepted lungs are declined on site. Several donor factors were associated with on-site decline, although lung allocation policy change did not have a consistent impact on on-site decline.

Outcomes of Treatment for Infective Endocarditis Following Transcatheter Pulmonary Valve Replacement.

BACKGROUND: Recipients of transcatheter pulmonary valve replacement (TPVR) have shown increased risk of infective endocarditis (IE). Little is known about the outcomes of different management strategies, particularly surgery, for IE after TPVR. METHODS: We queried the Pediatric Health Information System database for cases of IE after TPVR performed from 2010-2020. We described patient demographics, hospital courses, admission complications, and treatment outcomes based on therapy offered, surgical or medical only. We compared outcomes of initial therapy. Data are expressed as median or percent. RESULTS: Sixty-nine cases of IE were identified, accounting for 98 related hospital admissions; 29% of patients recorded IE-related readmissions. Of those readmitted after initial medical therapy only, 33% had relapse IE. Rates of surgery were 22% during initial admission and 36% overall. Likelihood of surgical intervention increased with each subsequent admission. Renal and respiratory failure were more common in those given initial surgery. Mortality rate was 4.3% overall and 8% in the surgical cohort. CONCLUSION: Initial medical therapy may result in relapses/readmissions and possible delay of surgical therapy, which appears to be most effective for treatment of IE. For those treated only medically, a more aggressive course of therapy may be more likely to prevent relapse. Mortality following surgical therapy for IE after TPVR appears higher than reported for surgical pulmonary valve replacement generally.

Creation of a Neo-Mitral Valve With Right Atrial Appendage Tissue in an Infant.

Mitral valve replacement in neonates and infants is a challenging operation with few good options. Neo-mitral valve reconstruction with right atrial appendage (RAA) may overcome some of the limitations of existing options.

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.

Evolution of Pulmonary Valve Management During Repair of Tetralogy of Fallot: A 14-year Experience.

BACKGROUND: The optimal repair strategy for tetralogy of Fallot remains controversial. This report presents a 14-year evolution of management of the pulmonary valve (PV) from transannular patch to valve-sparing repair to neovalve creation using living right atrial appendage tissue. METHODS: A retrospective review of 172 consecutive patients undergoing complete repair for TOF between January 2007 and June 2021 was performed. Clinical and follow-up data were analyzed by repair group. Neopulmonary valve (NPV) creation using right atrial appendage tissue was introduced in 2019. Failure of valve-sparing repair was defined as needing reintervention for recurrent right ventricular outflow tract obstruction (RVOTO). RESULTS: Median age and weight at repair were 4.9 months and 6 kg, respectively. Median preoperative PV size and z-score were 6.4 mm (5.2-8.3 mm) and -3.2 (-4.1 to -2.1), respectively. Patients who underwent valve-sparing repair had larger PV size and z-score compared with patients who underwent transannular patch procedures (8 mm vs 5.6 mm; -2.1 vs -3.2; both P < .001). There were no hospital mortalities. Overall follow-up was 44 months. At last follow-up, 10% of patients who underwent valve-sparing repair had repeat intervention for recurrent RVOTO. Patients who had failed valve-sparing repair had significantly lower PV z-scores (-2.6 vs -1.9; P = .01). An NPV was used in 8 patients with a median PV z-score of -4 (-4.7 to -3.9). At 6 months, 6 patients (75%) had mild or trivial pulmonary insufficiency after NPV placement. CONCLUSIONS: Repair of tetralogy of Fallot is a safe operation with excellent outcomes. Valve-sparing repair avoids right ventricular dilation but may fail for RVOTO at a PV z-score <-2. NPV creation offers an alternative option in patients with a small PV.

Multiple subtypes of coxsackievirus group B can cause congenital heart disease.

BACKGROUND: Different serotypes of coxsackievirus B (CVB), which is the most common cause of viral myocarditis, target cardiomyocytes through Coxsackie and Adenovirus Receptor and Decay-Accelerating Factor. Both receptors are expressed in the fetal heart. We hypothesized that infection with different serotypes of CVB during early pregnancy plays a role in pathogenesis of congenital heart defect (CHD). METHODS: In this study, we use a murine model to infect with CVB1, CVB4, and combination of CVB3 + CVB4 during a critical period in gestation. We examined offspring of pregnant mice for fetal death and heart defects following viral infection. RESULT: Fetuses from uninfected control dams showed normal heart development, while maternal CVB infection precipitates CHD: majorly ventricular septal defects (VSD) and non-compaction of ventricular myocardium (NC), with some infrequent cases of double outlet right ventricle, left ventricle wall rupture, right ventricle hypertrophy, and thickened/dysplastic semilunar valves. Infection of pregnant dams with CVB1 leads to 44% VSD and 41.2% NC cases, while with CVB4 leads to 31.7% VSD and 13.3% NC cases. Co-infection with CVB3 + CVB4 increases fetal pathology to 51.3% VSD and 41% NC cases. Infection can also result in fetal death, with higher incidences with CVB3 + CVB4 with 46.2% cases, compared to 33.3% by CVB1 and 21.7% by CVB4. Male fetuses were more susceptible to all phenotypes. CONCLUSION: Our report shows that prenatal CVB infections can lead to pathogenesis of certain heart defects in mouse model, particularly exacerbated with co-infections. This data confirms a link between prenatal CVB infection and CHD development and highlights it is not unique to just one serotype of CVB.

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.