Survival After Cardiac Transplantation in Adults With Single-Ventricle Congenital Heart Disease

Donor heart allocation systems in Europe. A scientific statement of the Heart Failure Association of the ESC

Heart transplantation remains the gold standard for treatment of most patients with advanced heart failure (HF), but despite improvements of organ recovery and utilization, donor heart scarcity remains a critically limiting factor. Detailed heart allocation systems (HASs) are in place to ensure use of organs for appropriate candidates, In Europe multiple, different HASs have evolved in different countries or communities of collaborating countries, like Eurotransplant or Scandiatransplant. In this scientific statement, we review the generic ethical and practical principles underlying allocation principles and examine and describe different European HASs with the purpose of discussing impact of outcomes for patients with advanced HF. It is shown that European HASs differ significantly with respect to which patients are prioritized and the methods by which the prioritization is performed. It is argued that the most commonly used parameter to describe success of a HAS, namely 1-year survival after heart transplantation, is a poor metric of HAS performance. The impact of HASs should be evaluated by several measures such as survival from listing, time to transplantation, the characteristics of patients undergoing heart transplantation, and over a longer time interval to understand the balance of early and late post-transplant risks and benefit. Mapping European HASs is a step towards understanding these factors and further research should determine the optimal HAS in a given HF population at a given time.

Neighborhood Socioeconomic Deprivation and Outcomes Following Heart Allograft Transplantation in Adults With Congenital Heart Disease

BACKGROUND

Socioeconomic disparities in the incidence and management of congenital heart disease (CHD) are well recognized. While neighborhood socioeconomic deprivation has been previously linked with inferior outcomes following heart transplantation (HT) among general adult cohorts, the impact of such disadvantage on outcomes among adult CHD (ACHD) patients listed for transplant remains unknown.

OBJECTIVES

The authors sought to elucidate the association of neighborhood socioeconomic disadvantage with waitlist and survival outcomes among ACHD HT candidates.

METHODS

All ACHD patients enrolled in the isolated HT waitlist from 2004 to 2023 were identified within the Organ Procurement and Transplantation Network. Socioeconomic disadvantage was quantified using the Area Deprivation Index. Patients with scores in the highest quintile were considered most deprived (others: less deprived). Survival was assessed using Kaplan-Meier and Cox proportional hazard models. To assess waitlist outcomes, we performed a Fine and Gray competing risk regression.

RESULTS

Of 1,830 ACHD patients, 366 (20%) were most deprived. Most deprived was of similar age, sex, and race, but more often publicly insured, compared to less deprived. Among transplant recipients, following risk adjustment, most deprived was associated with comparable mortality hazard at 1 (HR: 0.74; 95% CI: 0.48-1.14) and 5 years (HR: 0.91; 95% CI: 0.67-1.24). Among waitlisted candidates, competing risk analysis showed that most deprived faced similar likelihood of mortality or clinical deterioration (HR: 1.19; 95% CI: 0.84-1.68).

CONCLUSIONS

Among ACHD patients, greater neighborhood socioeconomic disadvantage was not linked with differential HT outcomes. In contrast to other populations, the multidisciplinary care and close follow-up ACHD patients receive may mitigate the negative impact of community disadvantage.

European Society of Organ Transplantation (ESOT) Consensus Statement on Machine Perfusion in Cardiothoracic Transplant

The machine perfusion (MP) of transplantable grafts has emerged as an upcoming field in Cardiothoracic (CT) transplantation during the last decade. This technology carries the potential to assess, preserve, and even recondition thoracic grafts before transplantation, so it is a possible game-changer in the field. This technology field has reached a critical turning point, with a growing number of publications coming predominantly from a few leading institutions, but still need solid scientific evidence. Due to the increasing need to expand the donor pool, especially in Europe, where the donor age is steeply increased, a consensus has been established to address the growing need and knowledge of machine perfusion in cardiothoracic transplantation, targeting the unmet scientific need in this growing field but also, priorities for development, and regional differences in utilization rates and organizational issues. To address MP in CT, the European Society of Organ Transplantation (ESOT) convened a dedicated Working group comprised of experts in CT to review literature about MP to develop guidelines that were subsequently discussed and voted on during the Consensus Conference that took place in person in Prague during the TLJ 3.0 in November 2022. The findings and recommendations of the Cardiothoracic Working Group on MP are presented in this article.

The impact of donor-recipient age difference on graft survival after heart transplant in adults with congenital heart disease

Background

The impact of donor-recipient age difference in adult congenital heart disease (ACHD) patients undergoing heart transplant (HT) is unknown.

Methods

ACHD patients (≥18 years old) who underwent HT (2000-2020) were identified using the United Network for Organ Sharing database. Graft survival through 10 years based on donor-recipient age difference was evaluated by comparing outcomes of donors >5 years older than recipients (Older), donors within 5 years of recipient age (Equal Age), and donors >5 years younger than recipients (Younger, reference group). Cox multivariable analysis was performed to evaluate the effect of donor-recipient age difference on early and late graft survival.

Results

A total of 1,275 ACHD patients underwent HT (60% male, median 35 years old (interquartile range 24-46) with median graft survival of 13.7 years (95% confidence interval [CI] 11.7-16.0). Compared to Younger donors (n = 306 [24%]), graft survival was similar with Equal Age donors (n = 698 [55%]; log-rank p = 0.61), though significantly reduced with Older donors (n = 271 [21%]; log-rank p = 0.03). In multivariable analysis, late graft survival was similar with Equal Age donors but lower with Older donors (adjusted hazard ratio 1.63, 95% CI 1.16-2.28, p = 0.005), with a trend of reduced survival with Older donors in recipients <30 or ≥40 years old.

Conclusions

Graft survival in ACHD patients undergoing HT was similar for those with Younger and Equal Age donors. Recipients with Older donors had reduced 10-year survival, possibly related to increased risk in those <30 and ≥40 years old. These data help inform the optimal donor age for ACHD patients requiring HT.

Validating the Concept of Mechanical Circulatory Support with a Rotary Blood Pump in the Inferior Vena Cava in an Ovine Fontan Model

Right-sided mechanical support of the Fontan circulation by existing devices has been compounded by the cross-sectional design of vena cava anastomosis to both pulmonary arteries. Our purpose was to investigate whether increasing inferior vena cava (IVC) flow with a rotary blood pump in the IVC only in an ovine animal model of Fontan would lead to acceptable superior vena cava (SVC) pressure. To achieve this, a Fontan circulation was established in four female sheep by anastomosing the SVC to the main pulmonary artery (MPA) and by interposing a Dacron graft between the IVC and the MPA. A rotary blood pump was then introduced in the graft, and the effect of incremental flows was observed at increasing flow regimen. Additionally, to stimulate increased pulmonary resistance, the experience was repeated in each animal with the placement of a restrictive band on the MPA distally to the SVC and Dacron graft anastomosis. Circulatory support of IVC flow alone increased the systemic cardiac output significantly, both with and without banding, indicating the feasibility of mechanical support of the Fontan circulation by increasing the flow only in the inferior vena cava. The increase in SVC pressure remained within acceptable limits, indicating the potential effectiveness of this mode of support. The findings suggest that increasing the flow only in the inferior vena cava is a feasible method for mechanical support of the Fontan circulation, potentially leading to an increase in cardiac output with acceptable increases in superior vena cava pressure.

Long-term outcomes of heart transplantation in adults with congenital heart disease: The impact of single-ventricle versus biventricular physiology

Objective

Congenital heart disease is a risk factor for mortality after orthotopic heart transplantation; however, the impact of preoperative circulation type and primary congenital heart disease diagnosis remains poorly delineated.

Methods

We retrospectively reviewed patients with adult congenital heart disease aged 16 years or more who underwent orthotopic heart transplantation at our institution between 2008 and 2022. Patients were categorized as having single-ventricle or biventricular circulation. The primary end point was 5-year post-transplant survival.

Results

Sixty-one patients with adult congenital heart disease (single-ventricle: n = 26 [42.6%], biventricular: n = 35 [57.4%]) underwent orthotopic heart transplantation at 33.7 [interquartile range, 19.1-48.7] years. The most common congenital heart disease diagnosis was hypoplastic left heart syndrome (n = 11, 42.3%) in the single-ventricle group and congenitally corrected transposition of the great arteries (n = 7, 20.0%) in the biventricular group. Twenty-four patients previously underwent Fontan palliation. At transplant, patients in the single-ventricle group were younger (18.5 [interquartile range, 17.6-32.3] years vs 45.0 [interquartile range, 33.0-52.2] years, P < .001) and more likely to have biopsy-proven cirrhosis (46.2% vs 14.3%, P = .01) and protein-losing enteropathy (42.3% vs 2.9%, P < .001). Patients in the single-ventricle group also had longer bypass times (223.4 ± 65.3 minutes vs 187.4 ± 59.5 minutes, P = .03) and longer durations of mechanical ventilatory support (3.5 [interquartile range, 2.0-6.0] days vs 1.0 [interquartile range, 1.0-2.0] days, P < .001). Operative mortality was comparable (11.5% vs 8.6%, P = 1). Median follow-up was 6.0 [interquartile range, 2.4-10.0] years. Five-year survival was worse in the single-ventricle group (66.0% ± 10.0% vs 91.3% ± 4.8%, P = .03), as was freedom from major rejection (58.3% ± 10.2% vs 84.0% ± 6.6%, P = .02). In univariable analysis, hypoplastic left heart syndrome and Fontan circulation were risk factors for post-transplant mortality (hypoplastic left heart syndrome: hazard ratio, 5.0, P < .001; Fontan: hazard ratio, 3.5, P = .03).

Conclusions

Adult patients with congenital heart disease undergoing heart transplant with single-ventricle physiology experienced a more complicated post-transplant course, with worse long-term survival and freedom from rejection. Multicenter studies are required to guide orthotopic heart transplantation decision-making in this complex cohort.

Heart Transplantation Following Fontan Failure: Long-Term Survival Analysis

Objectives: Fontan circulation presents significant challenges for patients with congenital heart disease, often necessitating heart transplantation (HTX) due to deteriorating functionality across multiple organ systems. However, the impact of prior Fontan palliation on HTX outcomes remains poorly understood, with early mortality rates suggesting a heightened risk. The aim of our study is to evaluate the long-term results after heart transplantation in patients with univentricular congenital heart disease previously palliated with Fontan circulation. Methods: A retrospective analysis was conducted on patients who underwent HTX for congenital heart disease. Patients were categorized into two groups based on the pre-HTX circulation pathway: the Failing Fontan Group (FFG) and the Biventricular Congenital Group (BCG). Data were collected from patients between 1987 and 2018. Early and late outcomes, including survival rates, were assessed and critically analyzed. Results: Of the 66 patients, 29 (43%) had a failing Fontan palliation (FFG), and 37 had biventricular congenital diseases (BCG) before heart transplantation. Early mortality (30-day) was not statistically different between the two group. The overall survival rate was 82.6 ± 13.9% at 1 year, 79.0 ± 14.9% at 5 years, 67.2 ± 17.6% at 10 years and 63.2 ± 18.2 ± at 15 years for the FFG, and 86.1 ±11.4% at 1 year, 79.5 ± 13.7% at 5 years, 75.7 ± 14.9% at 10 years, 75.7 ± 14.9% at 15 years for the BCG, with no statistically significant difference (Mantel Cox p value: 0.69, 0.89, 0.52 and 0.39, respectively). Regarding Cox-regression analysis, the long-term survival rate was not affected either by previous Fontan surgery or by the era of heart transplantation (before vs. after the year 2000). Conclusions: Although heart transplantation after Fontan palliation showed a higher risk in the early post-operative period, the medium- and long-term survival rates are comparable with biventricular circulation patients. Despite the failing Fontan patients being a challenging set of candidates for transplantation, it is a reasonable option in their treatment.

Editor-in-Chief's Top Picks From 2023

Each week, I record audio summaries for every paper in JACC, as well as an issue summary. This process has become a true labor of love due to the time they require, but I am motivated by the sheer number of listeners (16M+), and it has allowed me to familiarize myself with every paper that we publish. Thus, I have selected the top 100 papers (Original Investigations, Review Articles, Society Documents, and the Global Burden of Diseases) from distinct specialties each year. In addition to my personal choices, I have included papers that have been the most accessed or downloaded on our websites, as well as those selected by the JACC Editorial Board members. In order to present the full breadth of this important research in a consumable fashion, we will present these abstracts in this issue of JACC, as well as their Central Illustrations∗ and podcasts. The highlights comprise the following sections: Aorta; Basic and Translational Science; Cardiac Failure, Myocarditis, and Pericarditis; Cardiomyopathies and Genetics; Congenital Heart Disease; Coronary, Peripheral, and Structural Interventions; Coronavirus; Health Promotion and Preventive Cardiology; Imaging; Metabolic and Lipid Disorders; Neurovascular Disease and Dementia; Rhythm Disorders and Thromboembolism; and Valvular Heart Disease.1-104 ∗ To view the full manuscript, including the full-sized Central Illustration, please refer to the original publication in JACC.