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.

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.

Surgical management of hearts with isomeric atrial appendages

BACKGROUND AND AIM

On the basis of previously published accounts, coupled with our own experience, we have assessed the surgical approaches to patients with isomeric atrial appendages.

METHODS

We reviewed pertinent published studies on surgical treatment of individuals with isomeric atrial appendages, with the pertinent surgical details provided by most of the manuscripts.

RESULTS

Half of patients with right isomerism, and two-thirds of those with left isomerism have bilateral superior caval veins. Azygos extension of the inferior caval vein is reported in three-quarters of those with left isomerism. The coronary sinus is universally absent in right isomerism, along with totally anomalous pulmonary venous connection, and is absent in two-fifths of those with left isomerism. Univentricular atrioventricular connections are expected in up to three-quarters of those with right isomerism. Atrioventricular septal defect is reported in up to four-fifths, more frequently in right isomerism, with such patients typically having discordant ventriculoatrial connections or double outlet right ventricle. Reported mortalities extend to 85% for those with right, and 50% for those with left isomerism. In right isomerism, mortality is up to 54% for systemic-to-pulmonary arterial shunting, up to 75% for univentricular repair, and up to 95% for repair of totally anomalous pulmonary venous connection itself. No more than one-quarter had undergone Fontan completion, with reported mortalities of 21%.

CONCLUSION

Early surgical results are satisfactory in patients with left isomerism, but disappointing for those with right. Recent advances in cardiac and liver transplantation may offer improved survival.

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.

Intra-Extracardiac Total Cavopulmonary Connection for Patients With Anatomical Complexity

BACKGROUND

Currently, the extracardiac conduit total cavopulmonary connection (eTCPC) is the most widely used for Fontan modification worldwide. Nevertheless, there have been some cases that are difficult for performing eTCPC because of their anatomical complexity, such as apicocaval juxtaposition. For such cases, in 2002, we introduced the intra-extracardiac TCPC (ieTCPC).

METHODS

We reviewed our 20-year single-center experience with 316 TCPC patients to compare eTCPC (n = 277) and ieTCPC (n = 39) in terms of mortality and morbidity. ieTCPC was indicated for the cases in which there was concern that the TCPC conduit would be too curved for ordinary eTCPC.

RESULTS

Early death occurred in 1 patient and late death occurred in 15 patients. The actuarial survival rate in the eTCPC and the ieTCPC groups at 10 years were 95.1% and 100.0%, respectively. There was no significant difference in actuarial survival between eTCPC and ieTCPC patients. In the multivariate analysis, preoperative superior vena cava pressure and preoperative oxygen saturation were found to be the independent predictor for postoperative mortality. There was also no significant difference in actuarial rate of freedom from late-occurring complications between eTCPC and ieTCPC groups. In the multivariate analysis, dominant right ventricle and preoperative SVC pressure were independent predictors for late-occurring complications.

CONCLUSIONS

The clinical outcomes in patients who undergo eTCPC and ieTCPC appear to be excellent, with low mortality and morbidity rates in the midterm. ieTCPC may be a good option for TCPC cases with anatomical complexity such as apicocaval juxtaposition and separated hepatic vein drainage.

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.

Heterotaxy Is Not a Risk Factor for Adverse Long-Term Outcomes After Fontan Completion

BACKGROUND

Heterotaxy is considered a risk factor for poor outcomes after the Fontan operation. However, long-term data to support this notion are lacking. The aims of this study were to ascertain the long-term outcomes of patients with heterotaxy after hospital discharge after Fontan completion and to compare these outcomes with those of a contemporary nonheterotaxy cohort.

METHODS

A binational Fontan registry (n = 1540) was analyzed to identify patients with heterotaxy and compare them with patients without heterotaxy. The primary composite end point was Fontan failure, encompassing death, heart transplantation, Fontan takedown or conversion, protein-losing enteropathy, plastic bronchitis, or New York Heart Association functional class III or IV.

RESULTS

A total of 109 patients with heterotaxy were identified and they were compared with 1431 nonheterotaxy patients after Fontan completion. There was no difference in unadjusted 15-year freedom from Fontan failure (heterotaxy, 78% vs nonheterotaxy, 85%; P = .2). Patients in the heterotaxy group had a significantly higher cumulative incidence of post-Fontan arrhythmias (P < .001). Propensity-score matching for confounders yielded 73 patients with heterotaxy matched with 439 patients without heterotaxy, in whom 15-year freedom from Fontan failure was also not different (heterotaxy, 76% vs nonheterotaxy, 81%; P = .2). There was no difference in 15-year freedom from Fontan failure in patients with right vs left isomerism (right isomerism, 80% vs left isomerism, 76%; P = .7).

CONCLUSIONS

Although heterotaxy may complicate the pre-Fontan course, once the Fontan procedure is successfully completed, heterotaxy does not appear to be an important risk factor for Fontan failure. Patients with heterotaxy are at a higher risk of post-Fontan arrhythmias compared with patients without heterotaxy.

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.

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.

Understanding Stage II Bidirectional Cavopulmonary Shunts

Despite improvements in surgical technique and medical management, single-ventricle lesions remain one of the most challenging congenital heart anomalies to treat, and mortality rates are high. Most infants who have single-ventricle palliation undergo a sequence of surgeries to optimize pulmonary and systemic blood flow. The first surgery to separate pulmonary and systemic blood flow is the bidirectional cavopulmonary shunt. This article describes single-ventricle lesions and gives a basic overview of outcomes and strategies to improve interstage mortality. Preoperative investigations that evaluate stage II candidacy are reviewed along with surgical approaches and postoperative physiology. Although mortality rates are low and decreasing in patients with bidirectional cavopulmonary shunts, morbidity is still a challenge. Nurses must understand the pertinent anatomy and physiology and recognize postoperative complications early in order to reduce morbidity. Postoperative complications, management, outcomes and nursing care are discussed.

Non-cardiac issues in patients with heterotaxy syndrome

Management of complex congenital heart disease in patients with Heterotaxy syndrome (HS) has steadily improved. However, there is an insufficient appreciation of various non-cardiac issues that might impact the overall status of these patients. This article briefly reviews the implications of gastrointestinal, immunologic, genitourinary, respiratory, and central nervous system involvement in HS patients with a view to aid in their comprehensive clinical management.

Management and outcomes of heterotaxy syndrome associated with pulmonary atresia or pulmonary stenosis

BACKGROUND

Historic outcomes of patients with heterotaxy and pulmonary atresia or pulmonary stenosis (PA/PS) have been poor and in the current era are incompletely described. We reviewed our management of these patients and associated risk factors for death.

METHODS

We retrospectively reviewed the records of all patients with heterotaxy and PA/PS treated in our institution from January 1, 2002, to August 31, 2012. Death data were also confirmed with the Social Security Death Index. The log-rank test was done to assess six risk factors for death.

RESULTS

We identified 42 patients with heterotaxy and PA/PS. Median age at the first operation was 6.5 days, and median follow-up was 3.5 years. Death data were complete for all patients. Overall mortality was 19% (8 of 42). The 30-day, 1-year, and 5-year mortality estimation was 4.76%, 12.3%, and 19.1% respectively, as determined by the Kaplan-Meier method. The log-rank test showed total anomalous pulmonary venous return (TAPVR) (p<0.05) and obstructed TAPVR requiring an operation at less than 30 days (p=0.001) were significant risk factors for death.

CONCLUSIONS

In the current era, surgical treatment of heterotaxy and PA/PS can result in good outcomes. Associated TAPVR and obstructed TAPVR requiring neonatal correction were noted to be risk factors for death.

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.

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.