Outcomes of Multi-Organ Transplant in Adult Patients With Congenital Heart Disease

Trends and outcomes of heart transplantation in adults with congenital heart disease

OBJECTIVES

Heart transplantation for adult congenital heart disease is complicated and associated with challenging pretransplant support, long waiting and high early post-transplant mortality. We explored if surgical and medical advances and allocation system changes have affected outcomes.

METHODS

From United Network for Organ Sharing database, adults with congenital heart disease listed for heart transplantation were queried. To explore practice and outcome trends, patients were divided into 4 eras (eras 1-3: nearly 3 equal periods from 1992 to 2018, era 4: after 2018, corresponding with new allocation system). Univariate and multivariable analysis was performed to evaluate outcomes.

RESULTS

A total of 2737 patients were listed. There was gradual increase in listed and transplanted patients, along with significant increase in use of mechanical support, simultaneous kidney and liver transplantation. While proportion of transplanted remained constant, there was decrease in proportion delisted/died after listing (P = 0.01) and waiting list duration (P = 0.01), especially in era 4. Thirty-day post-transplant mortality remains high; however, it has significantly improved starting era 3 (P = 0.01). Current survival at 1-year and 5-years is 85% and 65%, with improvement mainly related to decreased early death. On multivariable analysis, factors associated with survival were lower glomerular filtration rate (hazard ratio = 0.99, P = 0.042), bilirubin (hazard ratio = 1.17, P<0.001) and mechanical ventilation (hazard ratio = 2.3, P=0.004).

CONCLUSIONS

Heart transplantation in adults with congenital heart disease is increasing, along with added complexity, higher usage of pretransplant mechanical support and simultaneous organ transplantation. Despite that, more complex patients do not experience worse outcomes. Early mortality improved but remains high. New donor allocation system allowed shorter waiting time and higher proportion transplanted without altering early mortality.

Long-Term outcomes in adult patients with congenital heart disease considered for transplantation: A single center study

BACKGROUND

Adult congenital heart disease (ACHD) patients pose unique challenges in identifying the time for transplantation and factors influencing outcomes.

OBJECTIVE

To identify hemodynamic, functional, and laboratory parameters that correlate with 1- and 10-year outcomes in ACHD patients considered for transplantation.

METHODS

A retrospective chart review of long-term outcomes in adult patients with congenital heart disease (CHD) evaluated for heart or heart + additional organ transplant between 2004 and 2014 at our center was performed. A machine learning decision tree model was used to evaluate multiple clinical parameters correlating with 1- and 10-year survival.

RESULTS

We identified 58 patients meeting criteria. D-transposition of the great arteries (D-TGA) with atrial switch operation (20.7%), tetralogy of Fallot/pulmonary atresia (15.5%), and tricuspid atresia (13.8%) were the most common diagnosis for transplant. Single ventricle patients were most likely to be listed for transplantation (39.8% of evaluated patients). Among a comprehensive list of clinical factors, invasive hemodynamic parameters (pulmonary capillary wedge pressure (PCWP), systemic vascular pressure (SVP), and end diastolic pressures (EDP) most correlated with 1- and 10-year outcomes. Transplanted patients with SVP < 14 and non- transplanted patients with PCWP < 15 had 100% survival 1-year post-transplantation.

CONCLUSION

For the first time, our study identifies that hemodynamic parameters most strongly correlate with 1- and 10-year outcomes in ACHD patients considered for transplantation, using a data-driven machine learning model.

Cardiac transplantation in adult congenital heart disease: a narrative review

Background and Objective

As more children with congenital heart disease survive to adulthood, adult congenital heart disease (ACHD) prevalence will increase (currently ~1 million US patients). Heart failure (HF) accounts for 26-42% of ACHD deaths. The rate of ACHD heart transplantations (ACHD HTx) is also increasing. We describe the ACHD HTx recipient/candidate cohort, analyze ACHD HTx outcomes, identify ACHD HTx specific challenges, and discuss opportunities to better serve more patients with ACHD HF.

Methods

PubMed literature search including articles published from 2010-2023. Reviewed 89 studies, 67 included. Our search focused on the challenges of ACHD HTx and potential solutions.

Key Content and Findings

ACHD HTx recipients are young [median age 35 years, interquartile range (IQR): 24-46 years]. 87-95% of ACHD HTx recipients had prior cardiac surgery. The most common underlying diagnoses include transposition of the great arteries (31%) and Fontan/Glenn circulation (28%). 63% of listed ACHD HTx candidates received a transplant within one year of listing. Post-transplant 1-year survival is 80%, 5-year survival 74%, and 10-year survival 59%. There are 4 unique ACHD HTx challenges: (I) difficulty in assessing pulmonary hypertension, resulting in some centers selecting oversized donor hearts. However, selecting oversized hearts does not improve post-operative mortality and could prolong waitlist time. (II) Increased immunologic sensitization, increasing rejection risk. Desensitization therapy has enabled sensitized HTx recipients to enjoy outcomes similar to non-sensitized recipients. (III) Procedural complexity with ~30% of cases requiring additional surgical reconstruction. Detailed multidisciplinary planning, extensive imaging, and transferring the patient into the operating room early can help manage the complexities and reduce organ ischemic time. (IV) Increased intraoperative bleeding due to patients' surgical histories and circulatory collaterals. Preoperative collateral coil embolization and select utilization of hypothermic circulatory arrest can help reduce bleeding. Additional Fontan specific challenges include extensive great artery repair, liver failure, plastic bronchitis, and protein loss enteropathy. Finally, given limited donor heart availability, mechanical circulatory support is a promising technology for patients with ACHD HF.

Conclusions

The prevalence of ACHD HTx is slowly but steadily increasing. The operational complexity of ACHD HTx can be managed, and the majority of recipients have excellent outcomes (59% 10-year survival).

National outcomes of bridge to multiorgan cardiac transplantation using mechanical circulatory support

BACKGROUND

Little is known regarding the profile of patients with multiorgan failure listed for simultaneous cardiac transplantation and secondary organ. In addition, few studies have reported how these patients are bridged with mechanical circulatory support (MCS). In this study, we examined national data of patients listed for multiorgan transplantation and their outcomes after bridging with or without MCS.

METHODS

United Network for Organ Sharing data were reviewed for adult multiorgan transplantations from 1986 to 2019. Post-transplant patients and total waitlist listings were examined and stratified according to MCS status. Survival was assessed via Cox regression in the post-transplant cohort and Fine-Gray competing risk regression with transplantation as a competing risk in the waitlist cohort.

RESULTS

There were 4534 waitlist patients for multiorgan transplant during the study period, of whom 2117 received multiorgan transplants. There was no significant difference in post-transplant survival between the MCS types and those without MCS in the whole cohort and heart-kidney subgroup. Fine-Gray competing risk regression showed that patients bridged with extracorporeal membrane oxygenation had significantly greater waitlist mortality compared with those without MCS when controlling for preoperative characteristics (subdistribution hazard ratio, 2.27; 95% confidence interval, 1.48-3.47; P < .001), whereas those bridged with a ventricular assist device had a decreased incidence of death compared with those without MCS (subdistribution hazard ratio, 0.78; 95% confidence interval, 0.63-0.96; P = .017).

CONCLUSIONS

MCS, as currently applied, does not appear to compromise the survival of multiorgan heart transplant patients. Waitlist data show that extracorporeal membrane oxygenation patients have profoundly worse survival irrespective of preoperative factors including organ type listed. Survival on the waitlist for multiorgan transplant has improved across device eras.

Consensus document for the selection of lung transplant candidates: An update from the International Society for Heart and Lung Transplantation

Tens of thousands of patients with advanced lung diseases may be eligible to be considered as potential candidates for lung transplant around the world each year. The timing of referral, evaluation, determination of candidacy, and listing of candidates continues to pose challenges and even ethical dilemmas. To address these challenges, the International Society for Heart and Lung Transplantation appointed an international group of members to review the literature, to consider recent advances in the management of advanced lung diseases, and to update prior consensus documents on the selection of lung transplant candidates. The purpose of this updated consensus document is to assist providers throughout the world who are caring for patients with pulmonary disease to identify potential candidates for lung transplant, to optimize the timing of the referral of these patients to lung transplant centers, and to provide transplant centers with a framework for evaluating and selecting candidates. In addition to addressing general considerations and providing disease specific recommendations for referral and listing, this updated consensus document includes an ethical framework, a recognition of the variability in acceptance of risk between transplant centers, and establishes a system to account for how a combination of risk factors may be taken into consideration in candidate selection for lung transplantation.

Transplantation for pulmonary arterial hypertension with congenital heart disease: Impact on outcomes of the current therapeutic approach including a high-priority allocation program

Patients with end-stage pulmonary arterial hypertension due to congenital heart disease have limited access to heart-lung transplantation or double-lung transplantation. We aimed to assess the effects of a high-priority allocation program established in France in 2007. We conducted a retrospective study to compare waitlist and posttransplantation outcomes before versus after implementation of the high-priority allocation program. We included 67 consecutive patients (mean age at listing, 33.2 ± 10.5 years) with pulmonary arterial hypertension due to congenital heart disease listed for heart-lung transplantation or double-lung transplantation from 1997 to 2016. At one month, the incidences of transplantation and death before transplantation were 3.5% and 24.6% in 1997-2006, 4.8% and 4.9% for patients on the regular list in 2007-2016, and 41.2% and 7.4% for patients listed under the high-priority allocation program (p < .001 and p = .0001, respectively). Overall survival was higher in patients listed in 2007-2016 (84.2% and 61.2% at 1 and 10 years vs. 36.8% and 22.1%, p = .0001). Increased incidence of transplantation, decreased waiting list mortality, and improved early and long-term outcomes were observed in patients with pulmonary arterial hypertension due to congenital heart disease listed for transplantation in the recent era, characterized by implementation of a high-priority allocation program.

Simultaneous Heart-Liver Transplantation for Congenital Heart Disease in the United States: Rapidly Increasing With Acceptable Outcomes

BACKGROUND AND AIMS

There are more adults than children living with congenital heart disease (CHD) in the United States, with a growing proportion requiring heart-liver transplantation (HLT). Our aim was to ascertain the frequency, outcomes, and prognostic factors in this patient population.

APPROACH AND RESULTS

United Network for Organ Sharing data on adult patients who underwent heart transplantation (HT) from 2009 through March 2020 were analyzed. The primary study outcome was patient survival. Cox proportional-hazards modeling assessed for mortality associations. There were 1,084 HT recipients: 817 (75.4%) CHD HTs only, 74 (6.8%) CHD HLTs, 179 (16.5%) non-CHD HLTs, and 14 (1.3%) heart-liver-kidney transplants. The number of CHD HLTs increased from a prior rate of 4/year to 21/year in 2019. Among patients with CHD, the 5-year survival rates were 74.1% and 73.6% in HTs only and HLTs, respectively (P = 0.865). There was a higher rate of allograft failure attributable to rejection in CHD HTs only compared with CHD HLTs (3.2% versus 0.4%; P = 0.014). Only 25 out of 115 HT-performing hospitals undertook CHD HLTs. Higher-volume centers (averaging one CHD HLT per year) had a 5-year patient survival rate of 83.0% compared with 61.3% in lower-volume centers (P = 0.079). Among HLT recipients, total bilirubin (hazard ratio [HR], 1.06; 95% confidence interval [CI], 1.01-1.12) and diabetes (HR = 2.97, 95% CI = 1.21-7.31) were independently associated with increased mortality risk, whereas CHD and age were not.

CONCLUSIONS

The rate of HLT for adult CHD in the United States is rising dramatically. The survival outcomes between CHD HT only and CHD HLT groups are comparable; however, the HLT group had lower rates of acute rejection. Among HLT recipients, diabetes and elevated bilirubin are associated with increased posttransplant mortality risk. An average of one CHD HLT per year could be considered a minimum quality metric at transplant centers.

Outcomes of Multi-Organ Transplant in Adult Patients With Congenital Heart Disease

Background

The prevalence of adult congenital heart disease (ACHD) is increasing in the United States because of improved survival into adulthood. The unique physiology of ACHD commonly leads to multiorgan dysfunction, prompting interest in outcomes after multiorgan (heart+X) transplantation.

Methods and Results

We queried the SRTR (Scientific Registry of Transplant Recipients) database to examine 5‐year outcomes in ACHD patients (aged ≥18 years) who underwent dual organ (heart+kidney/liver/lung) transplantation between 2000 and 2016. Cox proportional hazards models were constructed to look at survival of dual organ transplant recipients versus heart‐only recipients in the ACHD population and heart+lung recipients versus heart‐only recipients in the ACHD populations and versus non‐ACHD recipients of heart+lung transplant. We then constructed a multivariable model to investigate independent risk factors for 5‐year mortality after multiorgan transplant. Overall, 5‐year mortality was greater for multiorgan (heart+kidney/liver/lung) transplant compared with heart‐only transplant. On further analysis, only heart+lung transplant was associated with increased mortality. Outcomes after heart+lung transplant were no different between the ACHD and non‐ACHD population. Risk factors for increased risk of 5‐year mortality in ACHD patients after multiorgan transplant included heart+lung transplant, previous cardiac surgery, and severe functional limitation.

Conclusions

The mortality risk associated with multiorgan heart transplant in ACHD patients is attributable primarily to heart+lung transplants. Multiorgan transplant in ACHD does not convey increased risk compared with the non‐ACHD population. Need for multiorgan transplant should not be an impediment to listing ACHD patients needing a heart transplant.