Outcomes of heart transplants in children with heterotaxy syndrome.

OBJECTIVES: End-stage congenital heart disease (CHD) in children with heterotaxy syndrome might necessitate a heart transplant (HTx). An HTx in heterotaxy patients can be associated with several technical (e.g. redo, systemic/pulmonary-venous/situs anomalies, pulmonary artery reconstruction) and extra-cardiac (e.g. ciliary dyskinesia, infections, gastrointestinal) challenges. Our goal was to determine if heterotaxy syndrome is associated with increased early or late transplant risks. METHODS: The United Network for Organ Sharing transplant database was merged with the Paediatric Health Information System administrative database to identify children with heterotaxy who received an HTx. Characteristics and outcomes were compared between children with heterotaxy and contemporaneous non-heterotaxy congenital and non-congenital cardiomyopathy control groups. RESULTS: After we merged the databases, we divided our cohort of 1122 patients into 3 groups: the heterotaxy (n = 143), group the non-heterotaxy congenital (n = 428) group and the cardiomyopathy (n = 551) group. There were differences in the characteristics between the 3 groups, with the heterotaxy group being comparable to the non-heterotaxy congenital group. The waiting list duration was longer for the heterotaxy than for the non-heterotaxy congenital and cardiomyopathy groups (91 vs 63 vs 56 days, P < 0.001). Early post-transplant complications were similar for all groups except for operative mortality, which was 1% for the cardiomyopathy and 4% for the heterotaxy and non-heterotaxy congenital groups (P < 0.001). The post-transplant hospital stay was shorter for the cardiomyopathy (57 days) compared to the non-heterotaxy congenital (99 days) and heterotaxy (89 days) groups (P < 0.001). Whereas rejection prior to discharge was comparable between the heterotaxy and the CHD groups, it was higher at 1 year for the heterotaxy (22%) than for the non-heterotaxy congenital (19%) and cardiomyopathy (13%) groups (P < 0.001). Survival at 5 years was superior for the cardiomyopathy (87%) compared to the heterotaxy (69%) and non-heterotaxy congenital groups (78%) (P < 0.001). For the heterotaxy group, no risk factors affecting survival were identified on multivariable analysis. CONCLUSIONS: Regardless of the complexity, an HTx in selected children with heterotaxy is associated with good mid-term outcomes. Despite early results that are comparable to those of other patients with CHD, the increasing rejection rate at 1 year and the relatively accelerated attrition at mid-term warrant further follow-up. Due to database limitations in defining morphologic and surgical details, further work is warranted to delineate anatomical and surgical variables that could affect survival.

Total anomalous pulmonary venous connection: Influence of heterotaxy and venous obstruction on outcomes.

BACKGROUND: Previous studies have demonstrated increased early mortality and pulmonary vein reintervention for patients with total anomalous pulmonary venous connection (TAPVC) and heterotaxy syndrome (HTX+) compared with patients with TAPVC without heterotaxy syndrome (HTX-). We aimed to evaluate the longitudinal risk of pulmonary vein reintervention and mortality in HTX + patients. METHODS: A retrospective review was performed to identify longitudinal interventions in patients with TAPVC seen at a single center from 1995 to 2019. The mean cumulative interventions were described for all patients using the Nelson-Aalen estimator. Survival with TAPVC was described using Kaplan-Meier estimates. RESULTS: A total of 336 patients were identified with TAPVC, of whom 118 (35%) had heterotaxy syndrome. Functional single ventricles were identified in 106 of these 118 HTX + patients (90%) and in 14 of 218 HTX- patients (6%) (P < .001). Obstructed TAPVC (OBS+) was present in 49 of 118 HTX + patients (42%) and in 87 of 218 HTX- patients (40%) (P = .89). The median duration of follow-up was 6.5 years. Five-year survival was 69% for HTX+/OBS + patients, 72% for HTX+/OBS- patients, 86% for HTX-/OBS + patients, and 95% for HTX-/OBS- patients (P < .0001, log-rank test). The mean number of pulmonary vein interventions at the median follow-up time was greater in the HTX+/OBS + patients compared with HTX+/OBS- patients (mean, 2.0 vs 1.1; P = .030), HTX-/OBS + patients (mean, 1.3; P = .033), and HTX-/OBS- patients (mean, 1.3; P = .029). CONCLUSIONS: Among the 4 cohorts, HTX+ was associated with a higher rate of mortality, and HTX+/OBS+ was associated with a greater number of pulmonary vein interventions. This may be due in part to the high prevalence of single ventricle physiology in the HTX + cohort.

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.

Changes in Prognosis of Heterotaxy Syndrome Over Time.

BACKGROUND: Long-term outcomes in heterotaxy syndrome (HS) are poorly described. Some reports suggest improved survival in the recent era, whereas others do not. We sought to describe long-term outcomes and assess whether outcomes have changed over time. METHODS: Patients with HS born between 1985 and 2014 who had cardiac care (except initial palliation) at our institution were divided into 4 birth eras and survival over time was compared. Independent risk factors for mortality were identified by using Cox proportional hazards regression. In patients who underwent surgery, association between surgical pathway (univentricular versus biventricular repair) and mortality after adjusting for baseline confounders was evaluated. A risk stratification model was created by using classification and regression analysis. RESULTS: Among 264 patients, 118 (44.7%) had asplenia and 146 (55.3%) had polysplenia syndrome. Overall mortality was 40.2% (n = 106), with median follow-up of 10.2 years (longest 31.5 years). In multivariable analysis, pulmonary vein stenosis, coarctation, univentricular circulation, asplenia phenotype, and at least mild atrioventricular valve regurgitation at presentation were associated with mortality, whereas birth era was not. Among patients who underwent surgery, univentricular repair remained associated with mortality after adjustment. In classification and regression analysis, patients with biventricular circulation (especially those with polysplenia) had lower mortality than those with univentricular circulation. CONCLUSIONS: In this large retrospective study of HS, outcomes remain poor and have not improved since the early 1990s. We identified risks factors associated with earlier mortality and found that those with univentricular circulation and totally anomalous pulmonary venous connection had the worst prognosis. Survival was higher in those with biventricular circulation.

Isomerism of the atrial appendages: morphology and terminology.

BACKGROUND: Our aim is to identify the pathognomonic anatomical markers and the best terminology to describe the cardiac malformations associated with absent or multiple spleens, which are known as asplenia or polysplenia syndromes or isomerism. MATERIALS AND METHODS: We have reviewed 65 hearts with isomerism of atrial appendages of the Anatomical Collections of Congenital Heart Disease, Institute of Pathological Anatomy of the University of Padua consisting of 1800 specimens. All the hearts were classified according to sequential segmental classification. RESULTS: The incidence of isomerism was 3.6%. Of the total, 45 hearts with isomerism of right atrial appendages showed bilateral trilobed lungs, short bronchi, and absent spleen. The atrioventricular junction was univentricular in 49% of cases with a common atrioventricular valve in 91%. Pulmonary atresia and double outlet right ventricle were present in 40% and 47% of cases, respectively. Total anomalous pulmonary venous drainage and absent coronary sinus were always present. In 20 hearts with isomerism of left atrial appendages, bilateral bilobed lungs with long bilateral bronchi and multiple spleens were always found. The biventricular atrioventricular connection was present in 65% with a common valve in 30% of the hearts. The ventriculoarterial connection was concordant in 45% of cases, and aortic atresia and pulmonary atresia were both noted in 15% of each. An anomalous symmetric pulmonary venous drainage was observed in 65% of the hearts and interruption of inferior vena cava was found in 75% of cases. CONCLUSIONS: We believe that the appropriate terminology is based on the symmetrical morphology of the atrial appendages. The absence of the coronary sinus and the total anomalous pulmonary venous drainage are the markers of isomerism of the right atrial appendages. Symmetric pulmonary venous drainage and interruption of inferior vena cava are the markers of isomerism of left atrial appendages. In recent years, thanks to the improvement of clinical diagnosis and of surgical techniques these patients have the possibility to survive to adult age.

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 the Fontan Operation for Patients With Heterotaxy: A Meta-Analysis of 848 Patients.

BACKGROUND: Heterotaxy is considered a risk factor for adverse events at all stages in the pre-Fontan pathway, and Fontan outcomes are expected to be worse in patients with heterotaxy. The aim of this study was to review existing literature reporting outcomes of the Fontan operation systematically in patients with heterotaxy. METHODS: A systematic review and meta-analysis was performed to identify and synthesize early mortality and medium- and long-term survival in heterotaxy patients after the Fontan procedure. Subsequent outcome analyses were stratified by study period era, cohort size, and proportion of right versus left atrial isomerism to explore predictors of outcome. RESULTS: A total of 21 studies were included for analysis, which were composed of 848 post-Fontan heterotaxy patients. Early mortality varied between 1% and 30% with a weighted event rate of 14% (95% confidence interval [CI], 10%-19%). Survival at 1, 5, and 10 years was 86% (95% CI, 79%-91%), 80% (95% CI, 71%-87%), and 74% (95% CI, 59%-85%), respectively. Stratification by study period highlighted that studies with a median study period year of 1995 or later had similar early mortality and 1- and 5-year survival, but superior 10-year survival (P = .02) compared with earlier studies. Stratification by cohort size and right versus left atrial isomerism did not reveal subgroup differences. CONCLUSIONS: Compared with existing literature, in patients with heterotaxy, early mortality after Fontan is higher than for the overall Fontan population. Long-term survival is comparable to the overall Fontan cohort. When heterotaxy patients are successfully transitioned to Fontan, subsequent survival is acceptable and predictable. Long-term follow-up is lacking.

Trends in Infant Mortality After TAPVR Repair over 18 Years in Texas and Impact of Hospital Surgical Volume.

For some congenital heart lesions, higher institutional surgical volume has been associated with better survival than in lower volume centers. The relationship between institutional surgical volume and mortality in infants after total anomalous pulmonary vein return (TAPVR) repair has not been well explored. The Texas Inpatient Public Use Data File was queried for hospitalizations including TAPVR repair in infants between January 1, 1999 and December 31, 2016. We first evaluated the change in mortality over the study period. We then evaluated associations between institutional TAPVR surgical volume and mortality using univariable analysis and multivariable analysis accounting for center effects. For secondary analyses, we evaluated the association between volume and mortality among non-mutually exclusive TAPVR subsets, including isolated TAPVR, TAPVR with other congenital heart disease (CHD), TAPVR with heterotaxy, and TAPVR with single ventricle anatomy. Of 971 surgical hospitalizations that met inclusion criteria, 62% were male. Mortality after TAPVR repair decreased over the study period from 15.1% (1999-2004) to 7.6% (2012-2016) with an odds ratio per increasing year of 0.96 (95% CI 0.92-0.99, p = 0.030). By univariable analysis, earlier era, preterm birth, lower institutional surgical volume, heterotaxy, and additional CHD were associated with increased mortality. Institutional surgical volume remained significant in multivariate analysis with an odds ratio per increase in surgical volume of every 10 patients of 0.93 (95% CI 0.90-0.96, p < 0.001). When examining by subgroup, isolated TAPVR had the lowest mortality (n = 606, mortality = 6%), compared to TAPVR with other CHD (n = 359, mortality = 20%), TAPVR with heterotaxy (n = 135, mortality = 21%), and TAPVR with single ventricle (n = 128, mortality = 23%). In all groups except those with single ventricle, higher surgical volume was associated with lower mortality in multivariate analyses (isolated TAPVR p = 0.001, TAPVR with other CHD p = 0.009, TAPVR with heterotaxy p < 0.001, TAPVR with single ventricle p = 0.161). This is the first study to demonstrate an association between institutional surgical volume and mortality after TAPVR repair. Higher volume centers are associated with lower hospital mortality after TAPVR repair, including TAPVR with other CHD.

Outcomes in adults with congenital heart disease and heterotaxy syndrome: A single-center experience.

BACKGROUND: Heterotaxy syndrome (HS) is a condition in which the thoracoabdominal organs demonstrate an abnormal lateral arrangement and is often associated with congenital heart disease (CHD). Little is known about the adult HS population with CHD. OBJECTIVE: To describe the outcomes and sociodemographics of the adult CHD population with HS. METHODS: Records of patients 18 years of age or older with diagnoses of both CHD and HS at Texas Children's Hospital from 1964 to 2018 were reviewed. RESULTS: Sixty-two patients met inclusion criteria. Median age was 22.7 [IQR 19.6-30.0] years; 26 (42%) were female; and 13 (21%) of patients had a gap in care of >3 years. Median follow-up time in adulthood was 2.9 [IQR 1.3-8.2] years. Forty-three (69%) of patients had single ventricle heart disease, 31 (71%) of whom completed Fontan circulation. A total of 36 interventions occurred in 24 patients which included 16 cardiac catherization interventions, 13 electrophysiology-related procedures, and 18 surgical procedures including 2 orthotopic heart transplants. The median age for death or heart transplant was 45.3 (95%CI 34.3-56.1) years. Heart failure-free survival was 80.8 ± 5.2%, 58.7 ± 11.0%, and 31.1 ± 15.7% at 20, 30, and 40 years old, respectively. Cerebrovascular accident-free survival was 84.3 ± 5.1%, 54.2 ± 11.3%, and 40.6 ± 14.5% at 20, 30, and 40 years old, respectively. Tachyarrhythmia-free survival was 54.0 ± 7.1%, 29.2 ± 8.3%, and 19.5 ± 9.7% at 20, 30, and 40 years old and bradyarrhythmia-free survival was 66.0 ± 6.3%, 41.7 ± 9.4%, and 33.4 ± 10.6% at ages 20, 30, and 40 years, respectively. CONCLUSIONS: At a tertiary referral center, adult patients with CHD and HS have high rates of comorbidities and early death or heart transplant. Longitudinal surveillance and further exploration into factors associated with improved survival in this population are warranted.

Standardized Approach to Intervention for Intestinal Malrotation in Single Ventricle Patients with Heterotaxy Syndrome: Impact on Interstage Attrition and Time to Superior Cavopulmonary Connection.

Heterotaxy syndrome (HS) is a significant determinant of outcome in single ventricle (SV) physiology. Attrition rate and time-related events associated with intestinal malrotation (IM) are, yet, to be determined. We sought to evaluate hospital and interstage outcomes in relation with operative intervention for IM (IMO). Twelve SV/HS patients, who underwent IMO, from January 2004 to December 2016, were studied. Early shunt failure, time to superior cavopulmonary connection (SCPC) and interstage attrition were assessed. Since September 2014, based on a comprehensive standardized protocol, IMO was performed at the time of hospitalization for stage-I palliation (S1P) irrespective of clinical manifestations. Patients were assigned to Group A (n = 8): expectant /symptoms-driven versus Group B (n = 4): protocol-driven. At S1P 7 had systemic-to-pulmonary shunt (SPS), 1 SPS with anomalous pulmonary venous return (APVR) repair (Group A) compared to 2 SPS, 1 SPS with APVR repair and 1 Norwood operation (Group B). Median duration from S1P to IMO was 82 days (range 57-336; Group A) compared to 14 days (range 11-31; Group B); p < 0.05. Median age at IMO was 87 days (range 8-345) [Group A: 99 days (range 68-345) vs Group B: 25 days (range 8-39)] (p < 0.05). Early SPS failure occurred in 25% (2 of 8) for Group A compared to none in Group B (p < 0.05). Hospital mortality following IMO was 25% [Group A: 37.5% (3 of 8) vs Group B: 0; p < 0.05]. Interstage survival was 67% [Group A: 50% (4 of 8) vs Group B: 100%; p < 0.05]. Time to SCPC following S1P was 186 days (range 169-218) for Group A compared to 118 days (range 97-161) (Group B); p < 0.05. Operative intervention for IM in SV/HS is associated with significant interstage attrition and might impact the time to SCPC. SPS is at risk for early failure after IMO. A comprehensive standardized concept can mitigate detrimental implications.

Risk factors for death or heart transplantation in single-ventricle physiology (tricuspid atresia, pulmonary atresia, and heterotaxy): A systematic review and meta-analysis.

BACKGROUND: In this study we sought to evaluate risk factors (RFs) for death or heart transplantation (D-HT) in single-ventricle (SV) physiology due to tricuspid atresia (TA), pulmonary atresia‒intact ventricular septum (PA-IVS), and heterotaxy with SV (HX), clinical conditions for which outcome data are limited. METHODS: To conduct a systematic review, we included citations that evaluated occurrence of D-HT in SV physiology of TA, PA-IVS, and HX in English articles published between January 1998 and December 2017 based on inclusion and exclusion criteria, following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The Cochrane Risk of Bias in Non-Randomized Studies-Interventions (ROBINS-I) tool for non-randomized studies was used to assess the risk of bias. Meta-analysis was performed if RF data were available in more than 3 studies. RESULTS: Of 11,629 citations reviewed, 30 met inclusion criteria. All 30 were observational, retrospective studies. In all, 1,770 patients were included, 481 died and 21 underwent HT (63 lost to follow-up); 723 patients reached Fontan completion. We found that systemic ventricular dysfunction (odds ratio [OR] 20.7, confidence interval [CI] 10.0-42.5, I2 = 0%) and atrioventricular valve regurgitation (AVR) were associated with risk of D-HT (OR 3.7, CI 1.9-6.9, I2 = 14%). RF associations with D-HT could not be derived for right ventricle‒dependent coronary circulation, pulmonary arteriovenous malformations, total anomalous pulmonary venous return, arrhythmias, and pulmonary atresia. CONCLUSIONS: This systematic review and meta-analysis has identified a high mortality rate in children born with non-HLHS SV heart disease and points to potential under-utilization of HT. Systemic ventricular dysfunction and AVR were identified as RFs for D-HT in this subset of patients SV with TA, PA-IVS, and HX.

Cardiac Rhythm Disturbances in Heterotaxy Syndrome.

OBJECTIVE: Heterotaxy syndrome is associated with complex cardiac malformations and cardiac conduction system abnormalities. Those with right atrial isomerism (RAI) have dual sinus nodes and dual atrioventricular nodes predisposing them to supraventricular tachycardia (SVT). Those with left atrial isomerism (LAI) lack a normal sinus node and are at risk of sinus node dysfunction (SND) and atrioventricular block (AV block). We report the occurrence and risk factors associated with arrhythmias in heterotaxy syndrome. METHODS: A retrospective review of all heterotaxy syndrome patients born and treated at our institution between 2000 and 2014 was performed. RESULTS: A total of 40 patients were identified; 16/40 (40%) with LAI and 24/40 (60%) with RAI. There were 12 deaths during follow-up [LAI 3/16 (19%), RAI 9/24 (38%); p = 0.30]. Twenty-one patients had arrhythmias during a mean follow-up period of 5.4 years; 14/16 (87%) in LAI and 7/24 (29%) in RAI (p < 0.001). Freedom from arrhythmia at 1,3,5 years of age was 75.0%, 37.9%, 22.7% in LAI, and 83.3%, 77.5%, 69.6% in RAI, respectively(p = 0.00261). LAI had a three-fold increase in developing arrhythmias. Left atrial isomerism was the only factor identified to be associated with arrhythmia occurrence. CONCLUSIONS: Arrhythmias were commonly seen in heterotaxy syndrome particularly in left isomerism with more than half of the patients having arrhythmias by 3 years of age. Atrial situs was the only risk factor identified to be associated with arrhythmias, and close follow-up is warranted in these patients.

Timing of Fontan Completion in Children with Functionally Univentricular Hearts and Isomerism: The Impact of Age, Weight, and Pre-Fontan Arterial Oxygen Saturation.

Isomerism, or heterotaxy, impacts morbidity and mortality after various stages of univentricular palliation. Timing of Fontan completing in these patients based on preoperative factors has not been investigated previously. The aim of this study was to determine the impact of preoperative factors on various outcomes including length of hospital stay and duration of chest tubes. A cross-sectional study was conducted. Patients with isomerism having undergone Fontan at the Children's Hospital of Wisconsin between 1998 and 2014 were identified. Preoperative, operative, and postoperative data were collected on these patients. Linear regression analysis was conducted to determine preoperative characteristics associated with various postoperative outcomes. Receiver operator curve analysis was also performed to determine the sensitivity and specificity of age and pre-Fontan arterial oxygen saturation in predicting increased length of hospitalization and increased duration of chest tubes. Younger age and lower pre-Fontan arterial oxygen saturation were associated with increased length of hospitalization while younger age, lower pre-Fontan arterial oxygen saturation, interrupted inferior caval vein, and worse pre-Fontan atrioventricular valve regurgitation were associated with increased length of chest tubes. Age, arterial oxygen saturation, pulmonary arteriovenous malformations, interruption of the inferior caval vein, and atrioventricular valve regurgitation should all be taken into consideration when timing Fontan completion in patients with isomerism. Arterial oxygen saturations between 82 and 84% with an approximate age of 3 years appear to be a time at which it is reasonable to consider Fontan in patients with isomerism.

Increased mortality, morbidities, and costs after heart transplantation in heterotaxy syndrome and other complex situs arrangements.

OBJECTIVES: Identify pediatric heart transplant (HT) recipients with heterotaxy and other complex arrangements of cardiac situs (heterotaxy/situs anomaly) and compare mortality, morbidities, length of stay (LOS), and costs to recipients with congenital heart disease without heterotaxy/situs anomaly. METHODS: Using linked registry data (2001-2016), we identified 186 HT recipients with heterotaxy/situs anomaly and 1254 with congenital heart disease without heterotaxy/situs anomaly. We compared post-HT outcomes in univariable and multivariable time-to-event analyses. LOS and cost from HT to discharge were compared using Wilcoxon rank-sum tests. Sensitivity analyses were performed using stricter heterotaxy/situs anomaly group inclusion criteria and through propensity matching. RESULTS: HT recipients with heterotaxy/situs anomaly were older (median age, 5.1 vs 1.6 years; P < .001) and more often black, Asian, Hispanic, or "other" nonwhite (54% vs 32%; P < .001). Heterotaxy/situs anomaly was independently associated with increased mortality (hazard ratio, 1.58; 95% confidence interval, 1.19-2.09; P = .002), even among 6-month survivors (hazard ratio, 1.86; 95% confidence interval, 1.09-3.16; P = .021). Heterotaxy/situs anomaly recipients more commonly required dialysis (odds ratio, 2.58; 95% confidence interval, 1.51-4.42; P = .001) and cardiac reoperation (odds ratio, 1.91; 95% confidence interval, 1.17-3.11; P = .010) before discharge. They had longer ischemic times (19.2 additional minutes [range, 10.9-27.5 minutes]; P < .001), post-HT intensive care unit LOS (16 vs 13 days; P = .012), and hospital LOS (26 vs 23 days; P = .005). Post-HT hospitalization costs were also greater ($447,604 vs $379,357; P = .001). CONCLUSIONS: Heterotaxy and other complex arrangements of cardiac situs are associated with increased mortality, postoperative complications, LOS, and costs after HT. Although increased surgical complexity can account for many of these differences, inferior late survival is not well explained and deserves further study.

Inflammation, Active Fibroplasia, and End-stage Fibrosis in 172 Biliary Atresia Remnants Correlate Poorly With Age at Kasai Portoenterostomy, Visceral Heterotaxy, and Outcome.

Published histologic studies of the hilar plate or entire biliary remnant at the time of Kasai portoenterostomy (KHPE) have not provided deep insight into the pathogenesis of biliary atresia, relation to age at surgery, prognosis or the basis for successful drainage. We report detailed histologic findings in 172 centrally reviewed biliary remnants with an average of 6 sections per subject. Active lesions were classified as either necroinflammatory (rare/clustered in a few subjects) or active concentric fibroplasia with or without inflammation (common). Inactive lesions showed bland replacement by collagen and fibrous cords with little or no inflammation. Heterogeneity was common within a given remnant; however, relatively homogenous histologic patterns, defined as 3 or more inactive or active levels in the hepatic ducts levels, characterized most remnants. Homogeneity did not correlate with age at KHPE, presence/absence of congenital anomalies at laparotomy indicative of heterotaxy and outcome. Remnants from youngest subjects were more likely than older subjects to be homogenously inactive suggesting significantly earlier onset in the youngest subset. Conversely remnants from the oldest subjects were often homogenously active suggesting later onset or slower progression. More data are needed in remnants from subjects <30 days old at KHPE and in those with visceral anomalies. Prevalence of partially preserved epithelium in active fibroplastic biliary atresia lesions at all ages suggests that epithelial regression or injury may not be a primary event or that reepithelialization is already underway at the time of KHPE. We hypothesize that outcome after KHPE results from competition between active fibroplasia and reepithelialization of retained, collapsed but not obliterated lumens. The driver of active fibroplasia is unknown.

Long-term survival and phenotypic spectrum in heterotaxy syndrome: A 25-year follow-up experience.

BACKGROUND: Heterotaxy syndrome (HS) is a group of congenital disorders characterized by abnormal arrangement of thoraco-abdominal organs across the left-right axis of the body, classified as right (RAI) and left atrial isomerism (LAI)·We investigated the long-term survival and phenotypic spectrum in our HS cohort. Results are compared to literature data. METHODS: This is a single centre, observational, both retro and prospective study. Cardiac features, surgical management and abdominal ultrasound (US) of all HS patients were reviewed or investigated if missing. We evaluated all anatomical data and their clinical impact on survival, arrhythmias, infections, and heart transplant (HT). RESULTS: 136 patients were classified as RAI (81) and LAI (55). Long-term survival and freedom from HT reached 69.8% and 87.8% at 40 years in RAI and LAI, respectively. Multivariate analysis showed that LAI is an independent predictor for pacemaker implantation (p = 0.019). Splenic status varied in both groups: in RAI, abdominal US showed asplenia, polysplenia and normal spleen in 48%, 4% and 32% of patients, respectively, whereas in LAI polysplenia, asplenia and normal spleen occurred in 64%, 4% and 16% of cases, respectively. CONCLUSIONS: Mortality was significantly lower (9%) compared to literature (50%). Although patients with RAI experienced a higher mortality, no independent predictors were found. We demonstrated that the obsolete cardiac definition of "asplenia" and "polysplenia" instead of RAI and LAI is misleading, because of the high variability of the splenic phenotype among patients of both groups.

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.

Outcome of prenatally diagnosed fetal heterotaxy: systematic review and meta-analysis.

OBJECTIVES: The main aim of this systematic review was to evaluate the prevalence and type of associated anomalies in fetuses with heterotaxy diagnosed prenatally on ultrasound; the perinatal outcome of these fetuses was also studied. METHODS: An electronic search of MEDLINE, EMBASE and CINAHL databases was performed. Only studies reporting the prenatal diagnosis of isomerism were included. Outcomes observed included associated cardiac and extracardiac anomalies, fetal arrhythmia, abnormal karyotype, type of surgical repair and perinatal mortality. The analysis was stratified according to the type of heterotaxy syndrome (left (LAI) or right (RAI) atrial isomerism). Meta-analyses of proportions were used to combine data. Quality assessment of the included studies was performed using the Newcastle-Ottawa Scale for cohort studies. RESULTS: Sixteen studies (647 fetuses) were included in the analysis. Atrioventricular septal defect was the most common associated major cardiac anomaly found both in fetuses with LAI (pooled proportion (PP), 59.3% (95% CI, 44.0-73.7%)), with obstructive lesions of the right outflow tract occurring in 35.5% of these cases, and in fetuses with RAI (PP, 72.9% (95% CI, 60.4-83.7%)). Fetal arrhythmias occurred in 36.7% (95% CI, 26.9-47.2%) of cases with LAI and were mainly represented by complete atrioventricular block, while this finding was uncommon in cases with RAI (PP, 1.3% (95% CI, 0.2-3.2%)). Abnormal stomach and liver position were found, respectively, in 59.4% (95% CI, 38.1-79.0%) and 32.5% (95% CI, 11.9-57.6%) of cases with LAI, and in 54.5% (95% CI, 38.5-70.1%) and 45.9% (95% CI, 11.3-83.0%) of cases with RAI, while intestinal malrotation was detected in 14.2% (95% CI, 2.5-33.1%) of LAI and 27.1% (95% CI, 7.9-52.0%) of RAI cases. Hydrops developed in 11.8% (95% CI, 2.9-25.6%) of fetuses diagnosed prenatally with LAI. Biventricular repair was accomplished in 78.2% (95% CI, 64.3-89.4%) of cases with LAI, while univentricular repair or palliation was needed in 17.0% (95% CI, 9.7-25.9%); death during or after surgery occurred in 26.8% (95% CI, 4.6-58.7%) of LAI cases. Most children with RAI had univentricular repair and 27.8% (95% CI, 15.5-42.1%) died during or after surgery. CONCLUSIONS: Fetal heterotaxy is associated with a high prevalence of cardiac and extracardiac anomalies. Approximately one quarter of fetuses with heterotaxy died during or after surgery. Abnormal heart rhythm, especially heart block, is common in fetuses with LAI, while this finding is uncommon in RAI. Biventricular repair was common in LAI while univentricular repair was required in the majority of children affected by RAI. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Long-term outcome of patients with right atrial isomerism after common atrioventricular valve plasty.

OBJECTIVES: To review long-term outcomes of patients with right atrial (RA) isomerism who underwent common atrioventricular valve (CAVV) plasty. METHODS: We retrospectively analysed 59 patients with RA isomerism operated on between January 2004 and April 2016. We divided patients into those with CAVV plasty (CAVV plasty (+), 29 patients) and without CAVV plasty (CAVV plasty (-), 30), and we compared the outcome between the groups. We further divided patients into those with CAVV plasty before bidirectional cavopulmonary shunt (BCPS) operation (group before BCPS, 13 patients) or CAVV plasty with or after BCPS (group with or after BCPS, 16), and we compared the outcome between these groups. We reviewed the outcomes of 7 neonatal patients who underwent CAVV plasty. RESULTS: Kaplan-Meier estimated survival rates at 10 years were 70 ± 10% and 69 ± 9% in the CAVV plasty (+) and CAVV plasty (-) groups, respectively ( P = 0.45). Kaplan-Meier estimated survival rates at 10 years were 47 ± 17% and 85 ± 10% in the group before BCPS and group with or after BCPS, respectively ( P = 0.01). Among 7 neonates in the group before BCPS, 4 are alive; Kaplan-Meier estimated survival rates at 1 year and 5 years were 60 ± 20% and 30 ± 24%, respectively. CONCLUSIONS: Patients who underwent CAVV plasty with or after BCPS had good outcomes; the outcome of patients with CAVV plasty was the same as that of those without CAVV plasty. Treatment for patients who require CAVV plasty before BCPS, especially neonates, is challenging.

Bacteremia in Patients with Heterotaxy: A Review and Implications for Management.

Heterotaxy (HTX) is a laterality defect resulting in abnormal arrangement of the thoracic and abdominal organs across the right-left axis, and is associated with multiple anatomic and physiologic disruptions. HTX often occurs in association with complex congenital heart disease. Splenic abnormalities are also common and convey an increased risk of bacteremia (bacteremia) with a high associated mortality. We performed a systematic review of the literature studying the risk of infection in HTX patients and strategies that can be utilized to prevent such infections. Studies were identified for inclusion using PubMed, EMBASE, and OVID, as well as hand search of references from previously identified papers. Published studies specifically investigating bacteremia in HTX were identified and included as long as they were in English. Data were extracted by two separate authors independently with review of any findings that differed between the two authors. There were 42 documented cases of bacteremia in 32 patients. Approximately, 79% of these had absence of a spleen. The average age of bacteremia was 17 months. HTX patients are at high risk for bacteremia leading to mortality, regardless of anatomic splenic type. We propose strategies for the evaluation of splenic function in HTX patients, and review management practices to reduce the impact of infection risk in the HTX population.