Heterotaxy: lessons learned about patterns of practice and outcomes from the congenital heart surgery database of the society of thoracic surgeons

Contemporary Outcomes of Heart Transplantation in Children with Heterotaxy Syndrome: Sub-Optimal Pre-Transplant Optimization Translates into Early Post-Transplant Mortality

Patients with heterotaxy syndrome and congenital heart disease (CHD) experience inferior cardiac surgical outcomes. Heart transplantation outcomes are understudied, however, particularly compared to non-CHD patients. Data from UNOS and PHIS were used to identify 4803 children (< 18 years) undergoing first-time heart transplant between 2003 and 2022 with diagnoses of heterotaxy (n = 278), other-CHD (n = 2236), and non-CHD cardiomyopathy (n = 2289). Heterotaxy patients were older (median 5 yr) and heavier (median 17 kg) at transplant than other-CHD (median 2 yr and 12 kg), and younger and lighter than cardiomyopathy (median 7 yr and 24 kg) (all p < 0.001). UNOS status 1A/1 at listing was not different between groups (65-67%; p = 0.683). At transplant, heterotaxy and other-CHD patients had similar rates of renal dysfunction (12 and 17%), inotropes (10% and 11%), and ventilator-dependence (19 and 18%). Compared to cardiomyopathy, heterotaxy patients had comparable renal dysfunction (9%, p = 0.058) and inotropes (46%, p = 0.097) but more hepatic dysfunction (17%, p < 0.001) and ventilator-dependence (12%, p = 0.003). Rates of ventricular assist device (VAD) were: heterotaxy-10%, other-CHD-11% (p = 0.839 vs. heterotaxy), cardiomyopathy-37% (p < 0.001 vs. heterotaxy). The 1-year incidence of acute rejection post-transplant was comparable between heterotaxy and others (p > 0.05). While overall post-transplant survival was significantly worse for heterotaxy than others (p < 0.05 vs. both), conditional 1-year survival was comparable (p > 0.3 vs. both). Children with heterotaxy syndrome experience inferior post-heart transplant survival, although early mortality appears to influence this trend, with 1-year survivors having equivalent outcomes. Given similar pre-transplant clinical status to others, heterotaxy patients are potentially under risk-stratified. Increased VAD utilization and pre-transplant end-organ function optimization may portend improved outcomes.

Palliation of a Heterotaxy Single Ventricle Neonate with Pulmonary Atresia and Obstructed TAPVR

Patients born with obstructed total anomalous pulmonary venous return have a high risk of morbidity and mortality in the neonatal period, which only increases when combined with single ventricle physiology and non-cardiac congenital anomalies such as heterotaxy syndrome. Despite advances in management of congenital heart disease, surgery within the first weeks of life to repair the pulmonary venous connection and establish pulmonary blood flow with a systemic-to-pulmonary shunt has historically led to disappointing outcomes. A multidisciplinary approach with pediatric interventional cardiology and cardiac surgery is required to reduce morbidity and mortality in this extremely high-risk patient population. Extending the time between birth and cardiac surgery can lessen postoperative complications and mortality risk, especially in patients with abnormal thoracoabdominal relationships. Our team was able to successfully utilize transcatheter stent placement in a vertical vein and patent ductus arteriosus to delay and stage cardiac surgeries in an infant born with obstructed total anomalous pulmonary venous return, unbalanced atrioventricular septal defect with pulmonary atresia and heterotaxy, thus reducing the morbidity and mortality associated with this diagnosis.

Use of Interactive Visualization and 3D Printing in the Repair of Complex Congenital Heart Disease Presenting in Adult Life

We report a case of a 25-year-old male with a heterotaxy-like constellation of congenital heart defects consisting of complete atrioventricular septal defect, transposition of the great arteries, subpulmonary stenosis, L-looped ventricles, hypoplastic right ventricle, and a distant aorta arising from the right ventricle. This case demonstrates how 3D printing and interactive 3D visualization may facilitate a unique surgical repair.

Cardiac Laterality: Surgical Results of Right Atrial Isomerism

Right atrial isomerism (RAI) is a complex entity with varying diagnostic and treatment outcomes due to its rarity. Treatment options range from palliative to corrective surgeries, resulting in heterogeneous outcomes. The aim of this study was to analyze the results obtained after cardiac surgery in patients with RAI. A retrospective study was conducted, including patients diagnosed with RAI who underwent cardiac surgery. Their follow-up was from 1 January 2010 to 31 March 2020. Demographic characteristics and perioperative conditions were described. Thirty-eight patients were included, the median age was 4 years (IQR 2-9.2) and 57.9% were men. The main diagnoses were atrioventricular canal (63.2%) and pulmonary stenosis (55.3%). The most common surgical procedures were modified Blalock-Taussig shunt (65.8%) and total cavopulmonary connection with an extracardiac conduit fenestrated without cardiopulmonary bypass (15.9%). We did not find any factors associated with negative outcomes in these patients. The overall survival was 86.8%, with a better outcome in those who did not require reintubation (log rank, p < 0.01). The survival of RAI was similar to other centers. Individuals with RAI should be evaluated rigorously to determine an adequate repair strategy, considering high morbidity and mortality.

Fontan Palliation in Patients with Heterotaxy Syndrome: A Five Decade Experience

BACKGROUND

Patients with heterotaxy syndromes (right and left atrial isomerism) are at high risk of poor outcomes after single-ventricle palliation. However, the long-term outcomes and specific parameters associated with poor outcomes are incompletely understood.

METHODS

A retrospective review was performed of all patients with atrial isomerism who had a Fontan at our institution from 1973 to 2020. Standard demographic, as well as pre-, peri-, and postoperative parameters were collected. Features and outcomes of patients with polysplenia were compared to asplenia. Outcomes were analyzed for effect during 4 eras: (1: 1973-1984; n = 27), (2: 1985-1994; n = 93), (3: 1995-2004; n = 28), and (4: 2005-2020; n = 10).

RESULTS

Of the 1176 patients who had a Fontan operation, 158 (14%) had a heterotaxy syndrome. The median age at the time of Fontan was 8 (9) years. Early mortality was 20% and was greater in patients with asplenia compared to polysplenia (27% vs. 12%, p = .019). But it substantially improved over time (61% in era 1 vs. 7%-10% in the more recent eras (p < .001)), as did transplant-free survival (22% at 10 years in era 1 vs. 88% in era 4, p < .001). Transplant-free survival was significantly lower in patients with asplenia versus those with polysplenia (p = .014), and patients with heterotaxy had lower survival than nonheterotaxy (p = .01). This was largely due to the asplenia group (p < .001) (hazard ratio = 3.05, p = .007).

CONCLUSIONS

After Fontan operation, patients with heterotaxy, particularly asplenia, continue to demonstrate worse transplant-free survival than nonheterotaxy patients. Early mortality and long-term transplant-free survival have improved in more recent eras.

Post-operative Morbidity and Mortality After Fontan Procedure in Patients with Heterotaxy and Other Situs Anomalies

Heterotaxy is a complex, multisystem disorder associated with single ventricle heart disease and decreased survival. Ciliary dysfunction is common in heterotaxy and other situs abnormalities (H/SA) and may increase post-operative complications. We hypothesized that patients with H/SA have increased respiratory and renal morbidities and increased in-hospital mortality after Fontan procedure. We queried the Pediatric Health Information System database for hospitalizations with ICD-9/10 codes for Fontan procedure in patients aged 1 through 11 years from 2004 to 2019. H/SA was identified by codes for dextrocardia, situs inversus, asplenia/polysplenia, or atrial isomerism and compared to non-H/SA controls. Outcomes were in-hospital mortality or heart transplantation, ECMO, hemodialysis, length of stay (LOS), and mechanical ventilation or vasoactive medication use ≥ 4 days. We adjusted estimates with multivariable logistic regression. Of 7897 patients at 50 centers, 1366 (17%) met criteria for H/SA. H/SA had worse outcomes for all study measures: death/transplantation (1.9 vs 1.1%, OR 1.74 (95% CI 1.01-3.03); p = 0.047), ECMO (3.7 vs 2.3%, OR 1.74 (1.28-2.35); p < 0.001), hemodialysis (2.1 vs 1.2%, OR 1.66 (1.06-2.59); p = 0.026), prolonged mechanical ventilation (13.2% vs 7.6%, OR 1.85 (1.53-2.25); p < 0.001) and vasoactive medication use (29.4 vs 19.7%, OR 1.65 (1.43-1.90), and longer LOS (11 (8-17) vs 9 (7-14) days; p < 0.001). H/SA is associated with increased cardiovascular, renal, and respiratory morbidity, as well as in-hospital mortality after Fontan procedure. Attention to renal and respiratory needs may improve outcomes in this difficult population. The relationship between ciliary dysfunction and lung and renal morbidity should be explored further.

Discordant Post-natal Patterns in Fetuses With Heterotaxy Syndrome: A Retrospective Single-Centre Series on Outcome After Fetal Diagnosis

OBJECTIVE

Cardiac and extra-cardiac anomalies in 46 pre-natally diagnosed cases of heterotaxy were compared to post-natal anatomical patterns in order to reveal discordant findings. Second, the outcome of these fetuses was evaluated.

METHODS

Fetuses with heterotaxy, diagnosed in a tertiary referral centre, were analysed retrospectively. Based on the foetal abdominal situs view, right atrial isomerism (RAI) and left atrial isomerism (LAI) were defined as foetal sub-types. Post-natally, discordant anatomical patterns for broncho-pulmonary branching, atrial appendage morphology, and splenic status were further clarified with CT scans. In summary, the spectrum of pre-natally and post-natally detected cardiac and extra-cardiac anomalies is systematically reviewed. Necessary surgical interventions and mid-long-term outcomes were compared between the two sub-types in surviving infants.

RESULTS

A total of 46 fetuses with heterotaxy were included; LAI was diagnosed in 29 (63%) fetuses and RAI was diagnosed in 17 (37%) fetuses. Extra-cardiac anomalies were noted in 35% of fetuses. Seven out of the 29 fetuses (24%) with LAI had atrio-ventricular block (AVB) and four of these cases presented with hydrops. Twenty nine out of the 46 participating fetuses (63%) were live births, with 62% in the LAI group and 65% in the RAI group. Five fetuses were lost to follow-up. At the age of 1 year, the overall survival of live births [estimate (95% CI)] was 67% (48; 92%) in patients with LAI and 55% (32; 94%) in patients with RAI. At the age of 5 years, the estimates were 67% (48; 92%) in the LAI group and 46% (24-87%) in the RAI group. The median survival (first quartile; third quartile) was 11.1 (0.1; 14) years for patients with LAI and 1.3 (0.09; NA) years for patients with RAI. Of 17 children who had undergone cardiac surgery, five (29%) children achieved a bi-ventricular repair and 12 (70%) children achieved a uni-ventricular palliation. Three were primarily palliated, but converted to bi-ventricular thereafter. Foetal subtype definition of heterotaxy based on the abdominal situs and post-natal thoracic imaging studies showed a discordant pattern of broncho-pulmonary branching and atrial appendage anatomy in 40% of our live-born children.

CONCLUSION

Heterotaxy is a rare and complex condition with significant morbidity and mortality related to severe cardiac and extra-cardiac associations. Accurate pre-natal diagnosis can help identify the fetuses at risk and allow for timely intervention in a multi-disciplinary setting. Further studies are warranted to shed light on the exact sub-type definition in fetuses with heterotaxy and the presence of discordant post-natal patterns.

Risk analysis for patients with a functionally univentricular heart after systemic-to-pulmonary shunt placement

OBJECTIVES

To investigate risk factors for mortality after systemic-to-pulmonary (SP) shunt procedures in patients with a functionally univentricular heart using the Japan Cardiovascular Surgery Database registry.

METHODS

Clinical data from 75 domestic institutions were collected. Overall, 812 patients with a functionally univentricular heart who underwent initial SP shunt palliation were eligible for analysis. Patients with pulmonary atresia with an intact ventricular septum and patients with a SP shunt as part of the Norwood procedure were excluded. Risk factors for 30- and 90-day mortalities were analysed using a logistic regression model.

RESULTS

Median age and body weight at SP shunt placement were 41 days and 3.6 kg, respectively. Modified Blalock-Taussig shunt, central shunt and other types of SP shunts were applied in 689 (84.9%), 94 (11.8%) and 30 (3.7%) patients, respectively. Cardiopulmonary bypass was utilized in 410 patients (51%) for 128 min (median, 19-561). There were 411 isolated SP shunt procedures. Median hospital stay was 27 days, and 742 (91.4%) patients were discharged. The 30- and 90-day mortality rates were 3.4% and 6.0%, respectively. Placement of a central shunt was identified as a risk factor for 30-day mortality, while lower body weight, preoperative ventilator support, right atrial isomerism and coexistence of major aortopulmonary collateral arteries and an unbalanced atrioventricular septal defect were identified as risk factors for 90-day mortality.

CONCLUSIONS

SP shunt carries a high mortality rate in patients with a functionally univentricular heart when it is performed in smaller patients with complex cardiac anomalies.

Cardiac surgery in patients with atrial isomerism: Long-term results and outcomes

PURPOSE

The aim of the study was to identify, determine, and analyze the clinical and surgical outcomes of patients with atrial isomerism (AI) undergoing cardiac surgery.

METHODS

A retrospective study was carried out. Patients with diagnosis of AI undergoing cardiac surgery at the National Institute of Cardiology Ignacio Chávez, from January 1, 2010 and March 31, 2020 were included; demographic characteristics and perioperative conditions of the patients were considered.

RESULTS

Sixty-five patients were included, with an average age of 6.4 ± 4.9 years, 50.8% males. Thirty-eight (58.5%) had right atrial isomerism (RAI) and 27 (41.5%) had left atrial isomerism (LAI); univentricular physiology (78.5%) predominated. Atrioventricular septal defect (AVSD) in RAI and septal defects in LAI were identified as the main associated defects. The most common surgical procedures performed were modified Blalock-Taussig shunt (MBTS) (27.6%), MBTS with total anomalous pulmonary venous connection (TAPVC) repair (15.3%) and total cavopulmonary connection (TCPC) with an extracardiac conduit fenestrated (10.8%); 100% RAI required a univentricular approach, while in LAI it was 48.1%. Overall survival was 92.3%, with 100% survival in LAI with biventricular physiology and 86.8% in RAI with univentricular physiology.

CONCLUSIONS

The survival of our institution is similar to that of other referral centers, where patients with LAI had a better evolution than RAI; in addition, the univentricular approach was required in all with RAI. Patients with AI must undergo a rigorous evaluation to determine an adequate repair strategy, considering univentricular RAI with a high possibility of morbidity and mortality.

Improved heart transplant survival for children with congenital heart disease and heterotaxy syndrome in the current era: An analysis from the pediatric heart transplant society

BACKGROUND

Challenges exist with heterotaxy due to the complexity of heart disease, abnormal venous connections, and infection risks. This study aims to understand heart transplant outcomes for children with heterotaxy.

METHODS

All children with congenital heart disease listed for transplant from 1993 to 2018 were included. Those with and without heterotaxy were compared. Waitlist outcomes and survival post-listing and transplant were analyzed. Post-transplant risk factors were identified using multiphase parametric hazard modeling.

RESULTS

There were 4814 children listed, of whom 196 (4%) had heterotaxy. Heterotaxy candidates were older (5.8 ± 5.7 vs 4.2 ± 5.5 years, p < 0.01), listed at a lower urgency status (29.8% vs 18.4%, p < 0.01), more commonly single ventricle physiology (71.3% vs 59.2%, p < 0.01), and less often supported by mechanical ventilation (22% vs 29.1%, p < 0.05) or extracorporeal membrane oxygenation (3.6% vs 7.5%, p < 0.05). There were no differences in waitlist outcomes of transplant, death, or removal. Overall, post-transplant survival was worse for children with heterotaxy: one-year survival 77.2% vs 85.1%, with and without heterotaxy, respectively. Heterotaxy was an independent predictor for early mortality in the earliest era (1993-2004), HR 2.09, CI 1.16-3.75, p = 0.014. When stratified by era, survival improved with time. Heterotaxy patients had a lower freedom from infection and from severe rejection, but no difference in vasculopathy or malignancy.

CONCLUSIONS

Mortality risk associated with heterotaxy is mitigated in the recent transplant era. Early referral may improve waitlist outcomes for heterotaxy patients who otherwise have a lower status at listing. Lower freedom from both infection and severe rejection after transplant in heterotaxy highlights the challenges of balancing immune suppression.

Predicting Cardiac Anatomy, Physiology, and Surgical Management Based on Fetal Echocardiography in Heterotaxy Syndrome

OBJECTIVE

 Heterotaxy syndrome (HS) is often associated with complex congenital heart disease (CHD). While fetal echocardiography (FE) permits accurate prenatal identification of most CHD, the high level of disease complexity in HS may pose challenges in predicting postnatal findings and outcomes. This study aimed to define the accuracy of FE in predicting postnatal anatomy, physiology, and surgical management of CHD in the setting of HS.

STUDY DESIGN

 Retrospective single-center cohort study including all patients with a prenatal diagnosis of HS from 2003 to 2018. Anatomic diagnoses from FE reports were compared with postnatal echocardiogram, catheterization, and operative reports. Prenatal predictions were compared with postnatal outcomes with a focus on ductal dependence, time to first intervention (immediate, neonatal period, 1-6 months, or older than 6 months), and surgical approach (single or biventricular).

RESULTS

 There were 102 pregnancies with fetal HS resulting in 21 terminations, 5 fetal losses, and 76 live births. Of the live births, 55 had significant CHD and available postnatal data for review. Among this group, survival to 1 year was 62% and was no different comparing single versus biventricular surgical approach. FE diagnostic accuracy varied by anatomic feature and was the lowest for diagnosis of venous anatomy. Determination of postnatal care was most accurate for predicting single versus biventricular surgical approach (91%), followed by ductal dependence (75%). Accuracy for predicting time to first intervention was the lowest at 69%. The most common reason for an incorrect prediction was difficulty in assessing the severity of pulmonary stenosis.

CONCLUSION

 FE permits accurate predictions regarding surgical approach. Characterizing systemic and pulmonary veins is challenging, as is predicting ductal dependence and time to first intervention. These data suggest that despite the high diagnostic accuracy of CHD in HS, a circumspect approach may be reasonable with regard to predicting some anatomic details and postnatal management decisions.

KEY POINTS

· In HS, FE was most accurate for intracardiac anatomy.. · Diagnostic accuracy of venous anatomy was less reliable.. · Predicting surgical approach (single ventricle vs. biventricular) was highly accurate.. · Predicting ductal dependence and time-to-intervention were more challenging in some instances..

Outcomes of single ventricle palliation in infants with heterotaxy syndrome

 

OBJECTIVES

Heterotaxy is a known risk factor for morbidity and mortality in single ventricle palliation. In this study, we examined our experience with this challenging group of patients.

METHODS

Records of patients born between 2001 and 2019 with heterotaxy, who needed staged single ventricle palliation were retrospectively analysed.

RESULTS

A total of 53 patients were included in this study. Thirty-five (66%) patients had a right ventricular dominance, common atrioventricular septal defect was present in 37 (70%) patients. Anomalous pulmonary venous drainage was present in 29 (55%) patients. Forty-six (86%) patients underwent first-stage palliation. Forty-one (77.3%) patients received a bidirectional cavopulmonary connection. Thirty-one (58%) patients received total cavopulmonary connection (TCPC). Overall survival rate was 92% at 1 month, 74% at 1 year and 68% at 10 years. Twelve (22.6%) patients died before second palliation stage. Four (10%) patients died before TCPC. No patient died after TCPC. Independent risk factors for mortality in the multivariate COX regression were a presence of restrictive pulmonary blood flow (HR 3.23; 95% CI 1.02-10.2; P = 0.05) and greater than mild atrioventricular valve regurgitation (HR 3.57; 95% CI 1.27-10.0; P = 0.02).

CONCLUSIONS

Mortality and morbidity in patients with single ventricle and heterotaxy are high. Restrictive pulmonary blood flow needing early modulation and greater than mild atrioventricular valve regurgitation at presentation are independent risk factors for mortality. Total anomalous pulmonary venous connection was not identified as a risk factor in the current era.

The Evolving Surgical Burden of Fontan Failure: An Analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

BACKGROUND

Fontan failure often requires surgical therapy in the form of Fontan revision or heart transplantation. We sought to characterize national trends in the surgical burden of Fontan failure and identify risk factors for adverse outcomes.

METHODS

Fontan patients undergoing Fontan revision or transplantation from January 2010 to June 2018 were included. We evaluated baseline characteristics and outcomes and used multivariable logistic regression to identify risk factors for operative mortality and composite mortality and major morbidity.

RESULTS

A total of 1135 patients underwent Fontan revision (n = 598) or transplantation (n = 537) at 100 centers. Transplantations increased from 34 in 2010 to 76 in 2017, largely owing to an increase in patients with hypoplastic left heart syndrome (HLHS) (18 in 2010 to 49 in 2017), while Fontan revision decreased (75 in 2010 to 49 in 2017). Transplantation patients were younger (median 14 years of age vs 18 years of age; P < .001), more often had preoperative risk factors (66% vs 40%; P < .001), and more often had HLHS (51% vs 15%; P < .001). Operative mortality and composite major morbidity and mortality were 7.6% and 35% for transplantation and 7.1% and 22% for Fontan revision, respectively. Multivariable risk factors for mortality included older age (odds ratio [OR], 1.08/y; P = .007), presence of preoperative risk factors (OR, 3.33; P = .002), and concomitant pulmonary artery reconstruction (OR, 2.7; P = .029) for Fontan revision but only older age (OR, 1.06/y; P = .020) for transplantation.

CONCLUSIONS

Both transplantation and Fontan revision are associated with high morbidity and mortality. There has been evolution of practices in surgical therapy for Fontan failure, perhaps related to rising prevalence of HLHS staged palliation.

Surgical Management of Heterotaxy Syndrome: Current Challenges and Opportunities

Introduction:

Heterotaxy syndrome presents a unique challenge in surgical management, even in the current era. We hypothesized that certain anatomic subsets merit novel strategies.

Methods:

We analyzed morphologic details, surgeries, comorbidities, subsequent admissions, and survival using Kaplan-Meier methods and multivariable risk models from a single-institution experience of 103 consecutive patients with heterotaxy who underwent cardiac surgery between January 1, 1990, and May 31, 2016.

Results:

Of the 103 patients (50 males and 53 females), 31 had left atrial isomerism, 64 had right atrial isomerism (RAI), and 8 patients’ isomerism was indeterminate (IND), with first cardiac operation at a mean 1.0 year (standard deviation ±3.0 years) of age. Kaplan-Meier overall survival estimate was 83.1% at six months, 77.8% at one year, 65.9% at five years, and 52.1% at ten years. Survival was particularly low among RAI following repair of total anomalous pulmonary venous connection (TAPVC) at first operation, with one- and five-year survival of 57% and 46%, respectively. By multivariable analysis, the only risk factor for death during the early phase (hazard model) was repair of TAPVC at the first cardiac operation (hazard ratio [HR]: 4.4, P = .01), and risk factors during the longer term constant phase were atrioventricular valve (AVV) regurgitation (HR: 4.2, P < .01), male gender (HR: 3.7, P < .01), and two-ventricle repair (HR: 3.0, P = .02). Patients with heterotaxy undergoing the Fontan procedure had excellent subsequent survival (85% at ten years).

Conclusions:

This analysis of over 100 patients with heterotaxy identified TAPVC requiring initial repair as the major risk factor for early death and important AVV regurgitation as the major risk factor in the longer term. Survival with RAI and early repair of TAPVC were poor, with one-year mortality exceeding 40%. Patients with single ventricle completing the Fontan operation enjoyed outstanding ten-year survival (85%). Initial management of RAI requiring early repair of TAPVC remains challenging. For this high-risk subset, alternative strategies such as early referral for cardiac transplantation evaluation warrant consideration.

Outcomes of Multistage Palliation of Infants With Single Ventricle and Atrioventricular Septal Defect

Background:

Published palliation outcomes of infants with functional single ventricle (SV) and common atrioventricular septal defect (AVSD) are poor due to associated cardiac and extracardiac anomalies and development of atrioventricular valve (AVV) regurgitation. We report current palliation results.

Methods:

From 2002 to 2012, 80 infants with functional SV with AVSD underwent multistage palliation. Competing-risks analyses modeled events after first-stage surgery and Glenn (death/transplantation vs next palliation surgery) and examined factors associated with survival and AVV intervention.

Results:

Sixty-eight (80%) patients received neonatal palliation: modified Blalock-Taussig shunt (n = 33, 41%), Norwood (n = 20, 25%), and pulmonary artery band (n = 15, 19%), whereas 12 (15%) received primary Glenn. On competing-risks analysis, one-year following first-stage surgery, 29% of patients had died or received transplantation and 62% had undergone Glenn. Five years following Glenn, 9% of patients had died or received transplantation and 68% had undergone Fontan. Overall eight-year survival was 64% and was lower in patients with genetic syndromes (53% vs 82%), patients requiring concomitant total anomalous pulmonary venous connection repair (53% vs 69%), and those requiring neonatal palliation (48% vs 100%). Factors associated with mortality were unplanned reoperation (hazard ratio [HR]: 3.7 [1.7-8.0], P = .001) and extracorporeal membrane oxygenation use (HR: 7.1 [3.0-16.6], P < .001). Initial AVV regurgitation ≥ moderate was associated with AVV intervention (HR: 6.2 [2.4-16.1], P = .002) with eight-year freedom from death or AVV intervention of 25% in those patients.

Conclusions:

Patients with SV with AVSD are a distinct group and commonly have associated cardiac and extracardiac malformations that complicate care and affect survival. The development of AVV regurgitation requiring intervention is common but does not affect survival.

Single Ventricle and Total Anomalous Pulmonary Venous Connection: Implications of Prenatal Diagnosis

BACKGROUND

Single ventricle (SV) patients with total anomalous pulmonary venous connection (TAPVC) are at high risk. Given the limited published data available, we examined outcomes and the implications of a prenatal diagnosis of SV/TAPVC.

METHODS

A single-center, retrospective review was performed in neonates with SV/TAPVC from 1998 to 2014, identified through institutional databases. Patient demographic, perioperative, and follow-up data were collected.

RESULTS

Thirty-four eligible infants with SV/TAPVC were identified (mean birth weight: 3.0 kg). The TAPVC types were supracardiac (59%), infracardiac (21%), mixed (12%), and cardiac (9%). Heterotaxy syndrome was present in 25 (74%) infants. A prenatal diagnosis of SV was made in 26 (76%) infants, with TAPVC identified in 12 (35%). Seventeen (50%) had obstructed TAPVC within the first 48 hours of life; 7 of these patients had obstructed TAPVC identified prenatally. There were two preoperative deaths. Overall survival for the cohort was 65% at 1 year and 50% at 3 years. Survival in the obstructed group was significantly worse compared to the unobstructed group (47% vs 81% at 1 year; 27% vs 73% at 3 years, P = .01). Obstructed TAPVC and a prenatal prediction of obstructed TAPVC were significantly associated with postoperative mortality ( P = .01 and .03, respectively).

CONCLUSIONS

Patients with SV/TAPVC remain a high-risk group, with obstructed TAPVC a significant risk factor for mortality. Prenatal diagnosis of TAPVC in SV patients is challenging, but given those with obstructed TAPVC are especially at high risk, improved prenatal diagnostic techniques in this group may enhance counseling/delivery planning.

A Uniquely Abnormal Stool Specimen: A Case Report

BACKGROUND

Autoamputation of the appendix is a condition associated with the Ladd's procedure, a pediatric surgical technique for correction of intestinal malrotation. A 4-year-old male patient with a history of a Ladd's procedure performed as a newborn was brought in by his mother for "passing intestine" just prior to arrival. She reported that for several weeks her son had intermittent, crampy abdominal pain that resolved after the unusual-appearing bowel movement. After reviewing an image of the bowel movement, and in consultation with pediatric surgery, it was concluded that the patient had passed a devascularized appendix in his stool immediately prior to arrival.

CASE REPORT

A 4-year-old boy with a past medical history of heterotaxy syndrome (inversion of the thoraco-abdominal organs), a double outlet right ventricle, and Ladd's procedure presented to the Emergency Department (ED) after "passing intestine" in his stool. Close examination of the photo demonstrated a tubular structure with taenia, consistent with an appendix. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Autoamputation of the appendix is an uncommon presentation in the ED. Passing a devascularized appendix is a benign condition and can present with weeks of intermittent abdominal pain that resolves with passage of appendix in the stool. Remnants of the appendix can remain within the intestinal lumen years after the Ladd's procedure. Emergency physicians with a general awareness of this rare phenomenon can confidently make the diagnosis and reassure worried parents.

Primary Draining Vein Stenting for Obstructive Total Anomalous Pulmonary Venous Connection in Neonates with Right Atrial Isomerism and Functional Single Ventricle Improves Outcome

For neonates with right atrial isomerism (RAI), functional single ventricle (f-SV), and obstructive total anomalous pulmonary venous connection (TAPVC), primary TAPVC repair (TAPVCR) has a poor outcome. At our hospital, the survival rate at 1 year of such neonates undergoing primary TAPVCR between 1999 and 2010 (TAPVCR group) was 30% (3/10). Most deceased cases suffered from capillary leak syndrome and unstable pulmonary resistance after the surgeries. We sought to determine whether less invasive primary draining vein stenting (DVS) improved the outcome of these neonates. We investigated outcomes in consecutive nine such neonates (median gestational age 38 weeks, birth weight 2.8 kg, females 4) who underwent primary DVS with 6-mm-diameter Palmaz® Genesis® stents at our hospital between 2007 and 2017 (DVS group). Eight patients underwent subsequent surgeries to adjust the pulmonary flow after decreased pulmonary resistance. The survival rate at 1 year after the first interventions in the DVS group improved to 77% (7/9), although there was a difference between the interventional eras of the two groups. Of the seven patients who underwent multiple stent redilations with a larger balloon or additional stenting in other sites until the next stage of surgery at a median age of 8 months, four received a bidirectional Glenn (BDG) shunt and TAPVCR and three underwent TAPVCR, with two of those cases reaching BDG. Less invasive primary DVS improved the outcome of neonates with RAI, f-SV, and obstructive TAPVC, with many reaching BDG. Patient selection to advance toward Fontan is thought to further improve the outcome.

Noncompaction cardiomyopathy and heterotaxy syndrome

Left ventricular noncompaction cardiomyopathy (LVNC) is characterized by compact and trabecular layers of the left ventricular myocardium. This cardiomyopathy may occur with congenital heart disease (CHD). Single cases document co-occurrence of LVNC and heterotaxy, but no data exist regarding the prevalence of this association. This study sought to determine whether a non-random association of LVNC and heterotaxy exists by evaluating the prevalence of LVNC in patients with heterotaxy. In a retrospective review of the Indiana Network for Patient Care, we identified 172 patients with heterotaxy (69 male, 103 female). Echocardiography and cardiac magnetic resonance imaging results were independently reviewed by two cardiologists to ensure reproducibility of LVNC. A total of 13/172 (7.5%) patients met imaging criteria for LVNC. The CHD identified in this subgroup included atrioventricular septal defects [11], dextrocardia [10], systemic and pulmonary venous return abnormalities [7], and transposition of the great arteries [5]. From this subgroup, 61% (n = 8) of the patients developed arrhythmias; and 61% (n = 8) required medical management for chronic heart failure. This study indicates that LVNC has increased prevalence among patients with heterotaxy when compared to the general population (0.014-1.3%) suggesting possible common genetic mechanisms. Interestingly, mice with a loss of function of Scrib or Vangl2 genes showed abnormal compaction of the ventricles, anomalies in cardiac looping, and septation defects in previous studies. Recognition of the association between LVNC and heterotaxy is important for various reasons. First, the increased risk of arrhythmias demonstrated in our population. Secondly, theoretical risk of thromboembolic events remains in any LVNC population. Finally, many patients with heterotaxy undergo cardiac surgery (corrective and palliative) and when this is associated with LVNC, patients should be presumed to incur a higher peri-operative morbidity based on previous studies. Further research will continue to determine long-term and to corroborate genetic pathways.

Predictors of poor outcome among children with heterotaxy syndrome: a retrospective review

Objective

To determine predictors of poor outcome in patients with heterotaxy syndrome.

Methods

A retrospective review of children with heterotaxy syndrome, in a single tertiary paediatric cardiology centre, was conducted between 1 January 1997 and 1 January 2014 to determine predictors of poor outcome. Poor outcome was defined as death, cardiac transplantation or New York Heart Association (NYHA) functional class III or IV.

Results

There were 35 patients diagnosed with heterotaxy syndrome, 17 of whom were diagnosed antenatally. 22 patients had right atrial isomerism and 13 had left atrial isomerism. The median age of postnatal diagnosis was 2.5 days old (1 day to 19 months). 12 patients had a poor outcome; 6 patients died, 1 underwent cardiac transplantation and 5 had an NYHA functional class of >III. 5 patients had a biventricular repair and the remaining 30 had a univentricular repair. Type of atrial isomerism, univentricular or biventricular anatomy, severity of atrioventricular valve regurgitation or ventricular dysfunction, obstructed pulmonary venous return, occurrence of arrhythmia and presence of pulmonary atresia did not predict poor outcome. Fetal diagnosis also did not confer a survival advantage. The median duration of follow-up in this cohort was 65 months (2 days to 16.8 years).

Conclusions

Survival for patients with heterotaxy syndrome was 83% over a median follow-up of 65 months. 34% of patients had a poor outcome. None of the variables studied were predictive of death, transplantation or NYHA classification III or IV.

Heterotaxy Syndrome: Proceedings From the 10th International PCICS Meeting

A session dedicated to heterotaxy syndrome was included in the program of the Tenth International Conference of the Pediatric Cardiac Intensive Care Society in Miami, Florida in December 2014. An invited panel of experts reviewed the anatomic considerations, surgical considerations, noncardiac issues, and long-term outcomes in this challenging group of patients. The presentations, summarized in this article, reflect the current approach to this complex multiorgan syndrome and highlight future areas of clinical interest and research.

Screening and Treatment of Intestinal Rotational Abnormalities in Heterotaxy: A Systematic Review and Meta-Analysis

OBJECTIVE

To assess the role of screening and prophylactic surgery for intestinal rotational abnormalities (IRAs) in asymptomatic patients with heterotaxy.

STUDY DESIGN

PubMed, Embase, and Cinahl were searched electronically to determine the overall incidence of IRAs in heterotaxy; the detection rate of IRAs associated with screening; the incidence of midgut volvulus in patients without screening; and the incidence of morbidity and mortality after prophylactic and emergency Ladd procedures. Relevant data were computed with a meta-analysis of proportions. Between-study heterogeneity was assessed with the I(2) statistic.

RESULTS

From 276 papers identified, 24 studies with a total of 1433 patients with heterotaxy were included for systematic review. No randomized study was identified. True incidence of IRA in heterotaxy could not be ascertained through meta-analysis. In patients who underwent screening, the incidence of IRA was 58%. Acute midgut volvulus occurred in 5.8% of those who did not undergo screening. Postoperative mortality after Ladd procedure mainly was associated with cardiac insufficiency, and overall it was significantly greater in the emergency group compared with the prophylactic group (18% vs 5.6%). The complication rate also was greater in case of emergency vs prophylactic abdominal surgery (27% vs 16%); adhesional small bowel obstruction was the most common complication overall (6%).

CONCLUSION

The screen-detected incidences of IRA and acute midgut volvulus were significantly greater in heterotaxy than the normal population. Prophylactic Ladd procedure was associated with less morbidity and mortality compared with emergency surgery. A long-term prospective randomized trial is needed to define the indication for screening and prophylactic treatment of IRA in heterotaxy.

CHD associated with syndromic diagnoses: peri-operative risk factors and early outcomes

CHD is frequently associated with a genetic syndrome. These syndromes often present specific cardiovascular and non-cardiovascular co-morbidities that confer significant peri-operative risks affecting multiple organ systems. Although surgical outcomes have improved over time, these co-morbidities continue to contribute substantially to poor peri-operative mortality and morbidity outcomes. Peri-operative morbidity may have long-standing ramifications on neurodevelopment and overall health. Recognising the cardiovascular and non-cardiovascular risks associated with specific syndromic diagnoses will facilitate expectant management, early detection of clinical problems, and improved outcomes--for example, the development of syndrome-based protocols for peri-operative evaluation and prophylactic actions may improve outcomes for the more frequently encountered syndromes such as 22q11 deletion syndrome.

Racial disparities in heterotaxy syndrome

BACKGROUND

Heterotaxy syndrome (HTX) is a constellation of defects including abnormal organ lateralization and often including congenital heart defects. HTX has widely divergent population-based estimates of prevalence, racial and ethnic predominance, and mortality in current literature.

METHODS

The objective of this study was to use a population-based registry to investigate potential racial and ethnic disparities in HTX. Using the Texas Birth Defects Registry, we described clinical features and mortality of HTX among infants delivered from 1999 to 2006. We calculated birth prevalence and crude prevalence (cPR) ratios for infant sex, maternal diabetes, and sociodemographic factors.

RESULTS

A total of 353 HTX cases were identified from 2,993,604 births (prevalence ratio = 1.18 per 10,000 live births. HTX prevalence was approximately 70% higher among infants of Hispanic and non-Hispanic black mothers and 28% higher among female infants (cPR = 1.28; 95% confidence interval,1.04-1.59). There was a twofold higher female preponderance for infants of mothers who were non-Hispanic white or black. Mothers with diabetes were three times more likely to have a child with HTX compared with nondiabetics (cPR = 3.13; 95% confidence interval, 2.12-4.45). Among nondiabetics, HTX cases were 86% more likely to have a Hispanic mother and 72% a non-Hispanic black mother. First-year mortality for live born children with HTX was 30.9%.

CONCLUSION

This study represents one of the largest population-based studies of HTX to date, with a novel finding of higher rates of HTX among Hispanic infants of mostly Mexican origin, as well as among female infants of only non-Hispanic white and black mothers. These findings warrant further investigation.

Contemporary Outcomes of Surgical Repair of Total Anomalous Pulmonary Venous Connection in Patients With Heterotaxy Syndrome

BACKGROUND

Total anomalous pulmonary venous connection (TAPVC) is prevalent in patients with atriovisceral heterotaxy. Although functionally univentricular heart defects are common in heterotaxy syndromes, the extent to which this association influences overall risk for TAPVC repair is undefined. This study examines multiinstitutional experience with TAPVC repair in infants with heterotaxy using a national clinical registry.

METHODS

The Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSD) (2002-2012) was queried for patients with heterotaxy syndrome who underwent TAPVC repair, with or without concomitant procedures at age of 90 days or younger. The cohort was divided into single ventricle (SV) and non-single ventricle (non-SV) groups based on STS-CHSD codes. Patient characteristics and in-hospital outcomes were described.

RESULTS

Sixty-five centers reported 261 TAPVC repair operations (females, 115 [44%]; median [interquartile range] age and weight, 7 days [3-19 days] and 3.1 kg [2.7-3.5 kg]). Overall, 180 (69%) patients were identified with asplenia or right atrial isomerism, and 167 (64%) had SV diagnoses. Discharge mortality was 38%. Postoperatively, the median length of stay was 18 days (7-32 days), 20 (8%) patients required extracorporeal membrane oxygenation support, and 11 (4%) had reoperation for pulmonary vein stenosis. Mortality was higher for patients with SV defects (SV, 43% versus non-SV, 30%; p = 0.03). Length of stay, postoperative extracorporeal membrane oxygenation, and reoperation for pulmonary vein stenosis was similar between SV and non-SV groups. Overall, there was no difference in mortality for patients undergoing concomitant systemic-to-pulmonary artery shunt (p = 0.134) or surgery within 48 hours of birth (p = 0.876).

CONCLUSIONS

Total anomalous pulmonary venous connection repair in heterotaxy patients carries a high mortality risk, particularly with functionally univentricular physiology. These multiinstitutional data serve as an important benchmark and may be useful for risk stratification and counseling.

Current Outcomes of the Norwood Operation in Patients With Single-Ventricle Malformations Other Than Hypoplastic Left Heart Syndrome

Background:

Subsequent to increased experience with the Norwood operation in children with hypoplastic left heart syndrome (HLHS), its application has expanded to allow palliation of single-ventricle (SV) malformations other than HLHS. We describe current palliation outcomes in this group of SV patients.

Methods:

Between 2002 and 2012, 65 of the 303 Norwood operations were performed in non-HLHS SV patients. Competing risk analysis modeled events after Norwood and after subsequent Glenn and examined risk factors affecting outcomes.

Results:

Competing risk analysis showed that one year following Norwood, 24% of patients had died or received transplantation, 72% had undergone Glenn, and 4% were alive awaiting Glenn/Kawashima. Five years following Glenn, 9% of patients had died, 68% had undergone Fontan, and 23% were alive awaiting Fontan. Overall seven-year survival following Norwood was 68%. On multivariable analysis, mortality risk factors were unplanned cardiac reoperation (hazard ratio [HR]: 4.0 [1.5-10.6], P = .006), right dominant ventricle morphology (HR: 3.3 [1.3-8.3], P = .012), and postoperative extracorporeal membrane oxygenation (HR: 3.1 [1.1-9.0], P = .035).

Conclusions:

Operative death and interstage mortality continue to be problematic following Norwood palliation for non-HLHS SV variants. Outcomes seem comparable to those reported for HLHS, however they are influenced by underlying pathology; children with dominant left ventricle morphology (tricuspid atresia and double inlet left ventricle) have superior survival compared to those with dominant right ventricle morphology (mitral atresia, unbalanced atrioventricular septal defect, and most patients with atrial isomerism). Unplanned reoperations for technical imperfections diminish survival. Large multicenter studies might be warranted to better identify high-risk patients and provide guidance toward improving their survival.

Functionally univentricular heart and the fontan operation: lessons learned about patterns of practice and outcomes from the congenital heart surgery databases of the European association for cardio-thoracic surgery and the society of thoracic surgeons

BACKGROUND

"The term "functionally univentricular heart" describes a spectrum of congenital cardiovascular malformations in which the ventricular mass may not readily lend itself to partitioning that commits one ventricular pump to the systemic circulation and another to the pulmonary circulation." The purpose of this article is to review patterns of practice and outcomes in the Congenital Heart Surgery Databases (CHSDBs) of the European Association for Cardio-Thoracic Surgery (EACTS) and the Society of Thoracic Surgeons (STS) in patients with functionally univentricular hearts undergoing the Fontan operation.

METHODS

We examined all index operations performed on patients with functionally univentricular hearts in the EACTS and STS-CHSDBs over 4 years from 2007 to 2010, inclusive.

RESULTS

The most common diagnostic categories are hypoplastic left heart syndrome, tricuspid atresia, and double inlet left ventricle. The Fontan operation makes up 3.2% of all cardiac operations in the EACTS and STS-CHSDBs over 4 years from 2007 to 2010, inclusive. Of all the patients undergoing a Fontan procedure, 65.1% had an extracardiac Fontan, 21.5% had a lateral tunnel, and 5.8% had a Fontan revision or conversion (Re-do Fontan). In operations where fenestration status is known, 68.5% of the Fontan operations were fenestrated. During the four years of this analysis, only 5 patients had ventricular septation. Exclusive of Fontan revision or conversion (Re-do Fontan), all remaining Fontan operations had a discharge mortality of 2.3%. Fontan revision or conversion (Re-do Fontan) had a discharge mortality of 12.8%.

CONCLUSIONS

The STS database is largest CHSDB in North America. The EACTS database is largest CHSDB in Europe. This review of data from EACTS and STS allows for unique documentation of practice patterns and outcomes. From this analysis, it is clear that patients with functionally univentricular hearts present a challenging problem; however, exclusive of Fontan revision or conversion (Re-do Fontan), the Fontan operation has a discharge mortality of 2.3%.

Heterotaxy syndrome with malrotation of the gut and interrupted vena cava does not preclude safe procurement of multivisceral graft

We report the first successful procurement and transplantation of a multivisceral graft from a pediatric donor with polysplenic heterotaxy syndrome, including intestinal malrotation, midline liver with left-sided gallbladder and an interrupted inferior vena cava with azygous continuation. Procurement of the graft presented a surgical challenge in the presence of above anomalies. Modified approach to standard organ procurement and minor technical adaptation enabled successful transplantation. In an era of severe organ shortage of pediatric multivisceral grafts, a valuable organ offer should not lightly be declined for reasons of anatomic imperfections that might be overcome.

How insights from cardiovascular developmental biology have impacted the care of infants and children with congenital heart disease

To illustrate the impact developmental biology and genetics have already had on the clinical management of the million infants born worldwide each year with CHD, we have chosen three stories which have had particular relevance for pediatric cardiologists, cardiothoracic surgeons, cardiac anesthesiologists, and cardiac nurses. First, we show how Margaret Kirby's finding of the unexpected contribution of an ectodermal cell population - the cranial neural crest - to the aortic arch arteries and arterial pole of the embryonic avian heart provided a key impetus to the field of cardiovascular patterning. Recognition that a majority of patients affected by the neurocristopathy DiGeorge syndrome have a chromosome 22q11 deletion, have also spurred tremendous efforts to characterize the molecular mechanisms contributing to this pathology, assigning a major role to the transcription factor Tbx1. Second, synthesizing the work of the last two decades by many laboratories on a wide gamut of metazoans (invertebrates, tunicates, agnathans, teleosts, lungfish, amphibians, and amniotes), we review the >20 major modifications and additions to the ancient circulatory arrangement composed solely of a unicameral (one-chambered), contractile myocardial tube and a short proximal aorta. Two changes will be discussed in detail - the interposition of a second cardiac chamber in the circulation and the septation of the cardiac ventricle. By comparing the developmental genetic data of several model organisms, we can better understand the origin of the various components of the multicameral (multi-chambered) heart seen in humans. Third, Martina Brueckner's discovery that a faulty axonemal dynein was responsible for the phenotype of the iv/iv mouse (the first mammalian model of human heterotaxy) focused attention on the biology of cilia. We discuss how even the care of the complex cardiac and non-cardiac anomalies seen in heterotaxy syndrome, which have long seemed impervious to advancements in surgical and medical intensive care, may yet yield to strategies grounded in a better understanding of the cilium. The fact that all cardiac defects seen in patients with full-blown heterotaxy can also be seen in patients without obvious laterality defects hints at important roles for ciliary function not only in left-right axis specification but also in cardiovascular morphogenesis. These three developmental biology stories illustrate how the remaining unexplained mortality and morbidity of congenital heart disease can be solved.

Challenges of Univentricular Physiology in Heterotaxy

Patients with heterotaxy syndrome exhibit an extensive constellation of congenital cardiac malformations, making these patients a challenging group to manage surgically. Many of these patients' hearts do not lend themselves to separation of the pulmonary and systemic circulations except by some modification of the Fontan procedure. Palliative procedures early in life are directed at creating a satisfactory balance of pulmonary and systemic blood flow and at the same time ensuring unobstructed pulmonary venous return. Early conversion from parallel pulmonary and systemic circulations to superior cavopulmonary connections is important, to reduce volume work of the systemic ventricle. Heterotaxy patients are generally considered a high-risk population with respect to eventual Fontan procedure. It is important to appreciate the unique and variable anatomy of the sinus node and conduction system and the potential for occult pulmonary venous obstruction, atrioventricular valve regurgitation, and recurrent cyanosis, which may be related to the development of pulmonary arteriovenous malformations.