Expanding Heart Transplant in the Era of Direct-Acting Antiviral Therapy for Hepatitis C

For your consideration: Benefits of listing as willing to consider heart offers from donors with hepatitis C

BACKGROUND

Despite excellent outcomes of heart transplants from hepatitis C virus (HCV)-positive donors (D+), many candidates are not listed to even consider HCV D+ offers.

METHODS

Using the Scientific Registry of Transplant Recipients, we identified adult (age ≥18 years) heart transplant candidates prevalent on the waitlist between 2018 and March 2023. We compared the likelihood of waitlist mortality or heart transplant by candidate willingness to consider HCV D+ offers using competing risk regression.

RESULTS

We identified 19,415 heart transplant candidates, 68.9% of whom were willing to consider HCV D+ offers. Candidates willing to consider HCV D+ offers had a 37% lower risk of waitlist mortality (subhazard ratio [SHR], 0.63; 95% confidence interval [CI], 0.56-0.70; P < .001) than candidates not willing to consider HCV D+ offers, after adjustment for covariates and center-level clustering. Over the same period, heart transplant candidates willing to consider HCV D+ offers had a 21% higher likelihood of receiving a transplant (SHR, 1.21; 95% CI, 1.7-1.26; P < .001). As a result, among candidates willing to consider HCV D+ offers, 74.9% received a transplant and 6.1% died/deteriorated after 3 years, compared to 68.3% and 9.1%, respectively, of candidates not willing to consider HCV D+ offers. Lower waitlist mortality also was observed on subgroup analyses of candidates on temporary and durable mechanical circulatory support.

CONCLUSIONS

Willingness to consider HCV D+ heart offers was associated with a 37% lower risk of waitlist mortality and a 21% higher likelihood of receiving a transplant. We urge providers to encourage candidates to list as being willing to consider offers from donors with hepatitis C to optimize their waitlist outcomes and access to transplantation.

Breaking Barriers: Successful Outcomes of HCV D+/R- Transplants in HIV+ Recipients

Transplantation from donors with HCV-viremia to recipients without HCV-viremia (HCV D+/R-) is common, but no data exist for recipients with HIV or donors with HCV/HIV co-infection. We assessed outcomes of HCV D+/R- transplants within three HIV Organ Policy Equity Act studies of HIV+ abdominal transplantation to recipients with HIV between 2017-2023. Eighteen kidney and 6 liver HIV+ transplant recipients received organs from 19 donors with HCV viremia, including 7 with HCV/HIV co-infection. Median recipient age was 58 years, 96% were male, and median waitlist time was one year. All recipients had undetectable HIV RNA at time of transplant with median CD4 count 499 cells/mm3. HCV/HIV co-infected donors had median CD4 count 210 cells/mm3 and 4/7 had detectable HIV RNA. HCV treatment with direct acting antivirals was initiated at median 33 days post-transplant and sustained virologic response was achieved in 23/23 treated recipients without HCV-related adverse events; data unavailable for one participant. Kaplan-Meier survival analysis demonstrated 100% one-year and 96% three-year survival. Graft survival was 96% at one and three years. HCV D+/R- abdominal transplantation, including donors with HCV/HIV co-infection, demonstrates favorable patient and graft survival in recipients with HIV and is a viable strategy to increase organ utilization.

Utilization of Hepatitis C Virus-Infected Donor Hearts in Two Children and Two Young Adults: Initial Experience at a Pediatric Transplant Center

BACKGROUND

Although adult transplant centers are successfully transplanting organs from hepatitis C virus (HCV)-infected donors with detectable viral load by nucleic acid testing (NAT+) into HCV-negative recipients, this practice has not yet been adopted widely by the pediatric heart transplant community.

METHODS

We present a case series of four patients who received heart transplants from HCV NAT+ donors at a pediatric transplant center, including two pediatric patients < 18 years of age.

RESULTS

All recipients tolerated a 12-week course of glecaprevir/pibrentasvir and achieved a sustained virologic response with no HCV or liver complications with over 1 year of follow-up (range 1.4-2.5 years). All four have had good post-heart transplant outcomes with normal graft function and good functional status without rejection or cardiac allograft vasculopathy at time of last follow-up.

CONCLUSIONS

This case series details the successful multidisciplinary implementation of a protocol to accept cardiac allografts from HCV NAT+ donors for transplantation into HCV negative recipients at our pediatric transplant center. With the limited donor pool in pediatrics and the morbidity associated with prolonged durations on the transplant waitlist, pediatric centers should consider utilizing organs from HCV NAT+ donors to broaden the donor pool. Future work should evaluate other organs beyond heart and optimal timing and duration of direct acting antiviral therapy.

International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024

The "International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024" updates and replaces the "Listing Criteria for Heart Transplantation: International Society for Heart and Lung Transplantation Guidelines for the Care of Cardiac Transplant Candidates-2006" and the "2016 International Society for Heart Lung Transplantation Listing Criteria for Heart Transplantation: A 10-year Update." The document aims to provide tools to help integrate the numerous variables involved in evaluating patients for transplantation, emphasizing updating the collaborative treatment while waiting for a transplant. There have been significant practice-changing developments in the care of heart transplant recipients since the publication of the International Society for Heart and Lung Transplantation (ISHLT) guidelines in 2006 and the 10-year update in 2016. The changes pertain to 3 aspects of heart transplantation: (1) patient selection criteria, (2) care of selected patient populations, and (3) durable mechanical support. To address these issues, 3 task forces were assembled. Each task force was cochaired by a pediatric heart transplant physician with the specific mandate to highlight issues unique to the pediatric heart transplant population and ensure their adequate representation. This guideline was harmonized with other ISHLT guidelines published through November 2023. The 2024 ISHLT guidelines for the evaluation and care of cardiac transplant candidates provide recommendations based on contemporary scientific evidence and patient management flow diagrams. The American College of Cardiology and American Heart Association modular knowledge chunk format has been implemented, allowing guideline information to be grouped into discrete packages (or modules) of information on a disease-specific topic or management issue. Aiming to improve the quality of care for heart transplant candidates, the recommendations present an evidence-based approach.

Utilization and outcomes of expanded criteria donors in adults with congenital heart disease

BACKGROUND

Use of donation after circulatory death (DCD) and hepatitis C virus (HCV) positive donors in heart transplantation have increased the donor pool. Given poor waitlist outcomes in the adult congenital heart disease (ACHD) population, we investigated waitlist outcomes associated with willingness to consider DCD and HCV+ offers and post-transplant outcomes following HCV+ and DCD transplantation for these candidates.

METHODS

Using the United Network for Organ Sharing database, we identified adult ACHD candidates and recipients listed or transplanted, respectively, between 01/01/2016 and 09/30/2023 for the HCV analysis and between 12/01/2019 and 09/30/2023 for the DCD analysis. Among candidates, we compared the cumulative incidence of transplant, with waitlist death/deterioration as a competing risk, by willingness to consider HCV+ and DCD offers. Among recipients of HCV+ (vs HCV-) and DCD (vs brain death [DBD]) transplants, we compared perioperative outcomes and post-transplant survival.

RESULTS

Of 1,436 ACHD candidates from 01/01/2016 to 09/30/2023, 37.0% were willing to consider HCV+ heart offers. Of 886 ACHD candidates from 12/01/2019 to 09/30/2023, 15.5% were willing to consider DCD offers. On adjusted analysis, willingness to consider HCV+ offers was associated with 84% increased likelihood of transplant, and willingness to consider DCD offers was associated with 56% increased likelihood of transplant. Of 904 transplants between 01/01/2016 and 09/30/2023, 6.4% utilized HCV+ donors, and of 540 transplants between 12/01/2019 and 09/30/2023, 6.9% utilized DCD donors. Recipients of HCV+ (vs HCV-) and DCD (vs DBD) heart transplants had similar likelihood of perioperative outcomes and 1-year survival.

CONCLUSIONS

ACHD candidates who were willing to consider HCV+ and DCD offers were more likely to be transplanted and had similar post-transplant outcomes compared to recipients of HCV- and DBD organs.

Mid-term Waitlist and Posttransplant Outcomes With Hepatitis C-positive Donor Hearts

BACKGROUND

This study evaluates the clinical trends and impact of hepatitis C virus-positive (HCV+) donors on waitlist and posttransplant outcomes after heart transplantation.

METHODS

The United Network for Organ Sharing registry was queried to identify adult waitlisted and transplanted patients from January 1, 2015, to December 31, 2022. In the waitlist analysis, the candidates were stratified into 2 cohorts based on whether they were willing to accept HCV+ donor offers. Waitlist outcomes included 1-y cumulative incidences of transplantation and death/delisting. In the posttransplant analysis, the recipients were stratified into 2 cohorts with and without HCV nucleic acid test (NAT)-positive donors. Outcomes included 1- and 4-y posttransplant survival. Propensity score-matching was performed. Risk adjustment was performed using multivariable Cox regression.

RESULTS

During the study period, the number of centers using HCV NAT+ donors increased from 1 to 65 centers, along with the number of transplants. In the waitlist analysis, 26 648 waitlisted candidates were analyzed, and 4535 candidates (17%) were approved to accept HCV+ donors. Approval to accept HCV+ donors was associated with a higher likelihood of transplantation and a lower likelihood of death/delisting within 1 y of waitlisting. In the posttransplant analysis, 21 131 recipients were analyzed, and 997 recipients (4.7%) received HCV NAT+ hearts. The 1- and 4-y posttransplant survival were comparable between the recipients of HCV NAT+ and NAT- donors. Furthermore, the similar 1- and 4-y posttransplant survival persisted in the propensity score-matched comparison and multivariable Cox regression analysis.

CONCLUSIONS

Utilization of HCV+ donors is rising. Heart transplants using HCV+ donors are associated with improved waitlist and comparable posttransplant outcomes.

Increasing Multiorgan Heart Transplantations From Donation After Circulatory Death Donors in the United States

INTRODUCTION

Donation after circulatory death (DCD) donors are becoming an important source of organs for heart-transplantation (HT), but there are limited data regarding their use in multiorgan-HT.

METHODS

Between January 2020 and June 2023, we identified 87 adult multiorgan-HTs performed using DCD-donors [77 heart-kidney, 6 heart-lung, 4 heart-liver] and 1494 multiorgan-HTs using donation after brain death (DBD) donors (1141 heart-kidney, 165 heart-lung, 188 heart-liver) in UNOS. For heart-kidney transplantations (the most common multiorgan-HT combination from DCD-donors), we also compared donor/recipient characteristics, and early outcomes, including 6-month mortality using Kaplan-Meier (KM) and Cox hazards-ratio (Cox-HR).

RESULTS

Use of DCD-donors for multiorgan-HTs in the United States increased from 1% in January to June 2020 to 12% in January-June 2023 (p < 0.001); but there was a wide variation across UNOS regions and center volumes. Compared to recipients of DBD heart-kidney transplantations, recipients of DCD heart-kidney transplantations were less likely to be of UNOS Status 1/2 at transplant (35.06% vs. 69.59%) and had lower inotrope use (22.08% vs. 43.30%), lower IABP use (2.60% vs. 26.29%), but higher durable CF-LVAD use (19.48% vs. 12.97%), all p < 0.01. Compared to DBD-donors, DCD-donors used for heart-kidney transplantations were younger [28(22-34) vs. 32(25-39) years, p = 0.004]. Recipients of heart-kidney transplantations from DCD-donors and DBD-donors had similar 6-month survival using both KM analysis, and unadjusted and adjusted Cox-HR models, including in propensity matched cohorts. Rates of PGF and in-hospital outcomes were also similar.

CONCLUSIONS

Use of DCD-donors for multiorgan-HTs has increased rapidly in the United States and early outcomes of DCD heart-kidney transplantations are promising.

Transplant Vasculopathy Versus Native Atherosclerosis: Similarities and Differences

Cardiac allograft vasculopathy (CAV) is one of the leading causes of graft failure and death after heart transplantation. Alloimmune-dependent and -independent factors trigger the pathogenesis of CAV through activation of the recipients' (and to a lesser extent donor-derived) immune system. Early diagnosis of CAV is complicated by the lack of clinical symptoms for ischemia in the denervated heart, by the impact of early functional coronary alterations, by the insensitivity of coronary angiography, and by the involvement of small intramyocardial vessels. CAV in general is a panarterial disease confined to the allograft and characterized by diffuse concentric longitudinal intimal hyperplasia in the epicardial coronary arteries and concentric medial disease in the microvasculature. Plaque composition in CAV may include early fibrous and fibrofatty tissue and late atheromatous calcification. In contrast, native coronary atherosclerosis usually develops over decades, is focal, noncircumferential, and typically diminishes proximal parts of the epicardial vessels. The rapid and early development of CAV has an adverse prognostic impact, and current prevention and treatment strategies are of limited efficacy compared with established strategies in native atherosclerosis. Following acute coronary syndromes, patients after heart transplantation were more likely to have accompanying cardiogenic shock and higher mortality compared with acute coronary syndromes patients with native hearts.

Early Assessment of Cardiac Allograft Vasculopathy Risk Among Recipients of Hepatitis C Virus-infected Donors in the Current Era

BACKGROUND

Transplantation of hearts from hepatitis C virus (HCV)-positive donors has increased substantially in recent years following development of highly effective direct-acting antiviral therapies for treatment and cure of HCV. Although historical data from the pre-direct-acting antiviral era demonstrated an association between HCV-positive donors and accelerated cardiac allograft vasculopathy (CAV) in recipients, the relationship between the use of HCV nucleic acid test-positive (NAT+) donors and the development of CAV in the direct-acting antiviral era remains unclear.

METHODS AND RESULTS

We performed a retrospective, single-center observational study comparing coronary angiographic CAV outcomes during the first year after transplant in 84 heart transplant recipients of HCV NAT+ donors and 231 recipients of HCV NAT- donors. Additionally, in a subsample of 149 patients (including 55 in the NAT+ cohort and 94 in the NAT- cohort) who had serial adjunctive intravascular ultrasound examination performed, we compared development of rapidly progressive CAV, defined as an increase in maximal intimal thickening of ≥0.5 mm in matched vessel segments during the first year post-transplant. In an unadjusted analysis, recipients of HCV NAT+ hearts had reduced survival free of CAV ≥1 over the first year after heart transplant compared with recipients of HCV NAT- hearts. After adjustment for known CAV risk factors, however, there was no significant difference between cohorts in the likelihood of the primary outcome, nor was there a difference in development of rapidly progressive CAV.

CONCLUSIONS

These findings support larger, longer-term follow-up studies to better elucidate CAV outcomes in recipients of HCV NAT+ hearts and to inform post-transplant management strategies.

Racial and Gender Disparities in Transplantation of Hepatitis C+ Hearts and Lungs

BACKGROUND

Transplanting organs from hepatitis C virus (HCV)-infected donors into HCV-negative recipients has led to thousands of more transplants in the United States since 2016. Studies have demonstrated disparities in utilization of kidneys from these donors due to gender and education. It is still unknown, however, if the same disparities are seen in heart and lung transplantation.

METHODS

We used Organ Procurement and Transplantation/United Network for Organ Sharing data on all isolated heart and lung transplants from November 1, 2018, to March 31, 2023, classifying donors based on their HCV nucleic acid test (NAT) result: HCV-NAT- vs HCV-NAT+. We fit separate mixed-effects logistic regression models (outcome: HCV-NAT+ donor) for heart and lung transplants. Primary covariates included (1) race/ethnicity, (2) sex, (3) education level, (4) insurance type, and (5) transplant year.

RESULTS

The study included 26,108 adults (14,189 isolated heart transplant recipients and 11,919 isolated lung transplant recipients). A total of 993 (7.0%) heart transplants involved an HCV-NAT+ donor, compared to 457 (3.8%) lung transplants. In multivariable models among all isolated heart transplant recipients, women were significantly less likely to receive an HCV-NAT+ donor heart (odds ratio [OR]: 0.79, 95% confidence interval [CI]: 0.67-0.92, p = 0.003), as were Asian patients (OR: 0.52, 95% CI: 0.31-0.86, p = 0.01). In multivariable models among all isolated lung transplant recipients, Asians were significantly less likely to receive HCV-NAT+ transplants (OR: 0.31, 95% CI: 0.12-0.77, p = 0.01).

CONCLUSIONS

There are disparities in utilization of heart and lungs from HCV-NAT+ donors, with women and Asian patients being significantly less likely to receive these transplants.

Metabolomic profiling during ex situ normothermic perfusion before heart transplantation defines patterns of substrate utilization and correlates with markers of allograft injury

BACKGROUND

Cardiac metabolism is altered in heart failure and ischemia-reperfusion injury states. We hypothesized that metabolomic profiling during ex situ normothermic perfusion before heart transplantation (HT) would lend insight into myocardial substrate utilization and report on subclinical and clinical allograft dysfunction risk.

METHODS

Metabolomic profiling was performed on serial samples of ex situ normothermic perfusate assaying biomarkers of myocardial injury in lactate and cardiac troponin I (TnI) as well as metabolites (66 acylcarnitines, 15 amino acids, nonesterified fatty acids [NEFA], ketones, and 3-hydroxybutyrate). We tested for change over time in injury biomarkers and metabolites, along with differential changes by recovery strategy (donation after circulatory death [DCD] vs donation after brain death [DBD]). We examined associations between metabolites, injury biomarkers, and primary graft dysfunction (PGD). Analyses were performed using linear mixed models adjusted for recovery strategy, assay batch, donor-predicted heart mass, and time.

RESULTS

A total of 176 samples from 92 ex situ perfusion runs were taken from donors with a mean age of 35 (standard deviation 11.3) years and a median total ex situ perfusion time of 234 (interquartile range 84) minutes. Lactate trends over time differed significantly by recovery strategy, while TnI increased during ex situ perfusion regardless of DCD vs DBD status. We found fuel substrates were rapidly depleted during ex situ perfusion, most notably the branched-chain amino acids leucine/isoleucine, as well as ketones, 3-hydroxybutyrate, and NEFA (least squares [LS] mean difference from the first to last time point -1.7 to -4.5, false discovery rate q < 0.001). Several long-chain acylcarnitines (LCAC), including C16, C18, C18:1, C18:2, C18:3, C20:3, and C20:4, increased during the perfusion run (LS mean difference 0.42-0.67, q < 0.001). Many LCACs were strongly associated with lactate and TnI. The change over time of many LCACs was significantly different for DCD vs DBD, suggesting differential trends in fuel substrate utilization by ischemic injury pattern. Changes in leucine/isoleucine, arginine, C12:1-OH/C10:1-DC, and C16-OH/C14-DC were associated with increased odds of moderate-severe PGD. Neither end-of-run nor change in lactate or TnI was associated with PGD.

CONCLUSIONS

Metabolomic profiling of ex situ normothermic perfusion solution reveals a pattern of fuel substrate utilization that correlates with subclinical and clinical allograft dysfunction. This study highlights a potential role for interventions focused on fuel substrate modification in allograft conditioning during ex situ perfusion to improve allograft outcomes.

Special Considerations for Advanced Heart Failure Surgeries: Durable Left Ventricular Devices and Heart Transplantation

Heart transplantation and durable left ventricular assist devices (LVADs) represent two definitive therapies for end-stage heart failure in the modern era. Despite technological advances, both treatment modalities continue to experience unique risks that impact surgical and perioperative decision-making. Here, we review special populations and factors that impact risk in LVAD and heart transplant surgery and examine critical decisions in the management of these patients. As both heart transplantation and the use of durable LVADs as destination therapy continue to increase, these considerations will be of increasing relevance in managing advanced heart failure and improving outcomes.

Cardiac allograft vasculopathy in heart transplant recipients from hepatitis C viremic donors

BACKGROUND

Recent studies suggest the transplantation of Hepatitis C (HCV) hearts from viremic donors is associated with comparable 1 year survival to nonviremic donors. Though HCV viremia is a known risk factor for accelerated atherosclerosis, data on cardiac allograft vasculopathy (CAV) outcomes are limited. We compared the incidence of CAV in heart transplant recipients from HCV viremic donors (nucleic acid amplification test positive; NAT+) compared to non-HCV infected donors (NAT-).

METHODS

We retrospectively reviewed annual coronary angiograms with intravascular ultrasound from April 2017 to August 2020 at two large cardiac transplant centers. CAV was graded according to ISHLT guidelines. Maximal intimal thickness (MIT) ≥ 0.5 mm was considered significant for subclinical disease.

RESULTS

Among 270 heart transplant recipients (mean age 54; 77% male), 62 patients were transplanted from NAT+ donors. CAV ≥ grade 1 was present in 8.8% of the NAT+ versus 16.8% of the NAT- group at 1 year, 20% versus 28.8% at 2 years, and 33.3% versus 41.5% at 3 years. After adjusting for donor age, donor smoking history, recipient BMI, recipient, hypertension, and recipient diabetes, NAT+ status did not confer increased risk of CAV (HR.80; 95% CI.45-1.40, p = 0.43) or subclinical IVUS disease (HR.87; 95% CI.58-1.30, p = 0.49). Additionally, there was no difference in the presence of rapidly progressive lesions on IVUS.

CONCLUSION

Our data show that NAT+ donors conferred no increased risk for early CAV or subclinical IVUS disease following transplantation in a cohort of heart transplant patients who were treated for HCV, suggesting the short-term safety of this strategy to maximize the pool of available donor hearts.

Impact of the coronavirus disease 2019 pandemic on drug overdoses in the United States and the effect on cardiac transplant volume and survival

BACKGROUND

Drug overdose (DO) deaths rose to unprecedented levels during the coronavirus disease 2019 (COVID-19) pandemic. This study examines the impact of COVID-19 on the availability of cardiac allografts from DO donors and the implications of DO donor use on recipient survival.

METHODS

Heart transplants reported to the United Network for Organ Sharing from January 2017 to November 2019 ("pre-COVID") and from March 2020 to June 2021 ("COVID pandemic") were analyzed with respect to DO donor status. Outcomes were analyzed using Kaplan-Meier survival and Cox regression to identify predictors of survival. Characteristics of discarded cardiac allografts were also compared by DO donor status.

RESULTS

During the COVID-19 pandemic, 27.2% of cardiac allografts were from DO donors vs 20.5% pre-COVID, a 32.7% increase (p < 0.001). During the pandemic, DO donors were younger (84.7% vs 76.3% <40 years, p < 0.001), had higher cigarette use (16.1% vs 10.8%, p < 0.001), higher cocaine use (47.4% vs 19.7%, p < 0.001), and higher incidence of hepatitis C antibodies (26.8% vs 6.1%, p < 0.001) and RNA positivity (16.2% vs 4.2%, p < 0.001). While DO donors were less likely to require inotropic support (30.8% vs 35.4%, p = 0.008), they were more likely to have received cardiopulmonary resuscitation (95.3% vs 43.2%, p < 0.001). Recipient survival was equivalent using Kaplan-Meier analysis (log-rank, p = 0.33) and survival probability at 36 months was 85.6% (n at risk = 398) for DO donors vs 83.5% (n at risk = 1,633) for all other donors. Cox regression demonstrated that DO donor status did not predict mortality (hazard ratio 1.05; 95% confidence interval 0.90-1.23, p = 0.53).

CONCLUSIONS

During the COVID-19 pandemic, there was a 32.7% increase in heart transplants utilizing DO donor hearts, and DO became the most common mechanism of death for donors. The use of DO donor hearts did not have an impact on short-term recipient survival.

A gentler approach to monitor for heart transplant rejection

Despite developments in circulating biomarker and imaging technology in the assessment of cardiovascular disease, the surveillance and diagnosis of heart transplant rejection has continued to rely on histopathologic interpretation of the endomyocardial biopsy. Increasing evidence shows the utility of molecular evaluations, such as donor-specific antibodies and donor-derived cell-free DNA, as well as advanced imaging techniques, such as cardiac magnetic resonance imaging, in the assessment of rejection, resulting in the elimination of many surveillance endomyocardial biopsies. As non-invasive technologies in heart transplant rejection continue to evolve and are incorporated into practice, they may supplant endomyocardial biopsy even when rejection is suspected, allowing for more precise and expeditious rejection therapy. This review describes the current and near-future states for the evaluation of heart transplant rejection, both in the settings of rejection surveillance and rejection diagnosis. As biomarkers of rejection continue to evolve, rejection risk prediction may allow for a more personalized approach to immunosuppression.

Heart transplantation: advances in expanding the donor pool and xenotransplantation

Approximately 65 million adults globally have heart failure, and the prevalence is expected to increase substantially with ageing populations. Despite advances in pharmacological and device therapy of heart failure, long-term morbidity and mortality remain high. Many patients progress to advanced heart failure and develop persistently severe symptoms. Heart transplantation remains the gold-standard therapy to improve the quality of life, functional status and survival of these patients. However, there is a large imbalance between the supply of organs and the demand for heart transplants. Therefore, expanding the donor pool is essential to reduce mortality while on the waiting list and improve clinical outcomes in this patient population. A shift has occurred to consider the use of organs from donors with hepatitis C virus, HIV or SARS-CoV-2 infection. Other advances in this field have also expanded the donor pool, including opt-out donation policies, organ donation after circulatory death and xenotransplantation. We provide a comprehensive overview of these various novel strategies, provide objective data on their safety and efficacy, and discuss some of the unresolved issues and controversies of each approach.

Heart Transplant and Donors After Circulatory Death: A Clinical-Preclinical Systematic Review

INTRODUCTION

Heart transplantation is the treatment of choice for end-stage heart failure. There is a mismatch between the number of donor hearts available and the number of patients awaiting transplantation. Expanding the donor pool is critically important. The use of hearts donated following circulatory death is one approach to increasing the number of available donor hearts.

MATERIALS AND METHODS

A systematic review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines utilizing Pubmed/MEDLINE and Embase. Articles including adult human studies and preclinical animal studies of heart transplantation following donation after circulatory death were included. Studies of pediatric populations or including organs other than heart were excluded.

RESULTS

Clinical experience and preclinical studies are reviewed. Clinical experience with direct procurement, normothermic regional perfusion, and machine perfusion are included. Preclinical studies addressing organ function assessment and enhancement of performance of marginal organs through preischemic, procurement, preservation, and reperfusion maneuvers are included. Articles addressing the ethical considerations of thoracic transplantation following circulatory death are also reviewed.

CONCLUSIONS

Heart transplantation utilizing organs procured following circulatory death is a promising method to increase the donor pool and offer life-saving transplantation to patients on the waitlist living with end-stage heart failure. There is robust ongoing preclinical and clinical research to optimize this technique and improve organ yield. There are also ongoing ethical considerations that must be addressed by consensus before wide adoption of this approach.

Utilization of hepatitis C virus infected donors in heart transplant recipients with elevated MELD-XI score

BACKGROUND

The advent of direct-acting antivirals has helped to increase the safe utilization of organs from hepatitis C virus positive (HCV+) donors. However, the outcomes of heart transplantation (HT) using an HCV+ donor are unclear in recipients with underlying liver disease represented by an elevated model for end-stage liver disease excluding international normalized ratio (MELD-XI).

METHODS

The United Network of Organ Sharing database was queried from Jan 2016 to Dec 2021. Post-transplant outcomes stratified by recipient MELD-XI score (low <10.37, medium, 10.38-13.39, and high >13.4) was compared between patients with HT from HCV+ (N = 792) and patients with HT from HCV-negative donors (N = 15,266).

RESULTS

The median MELD-XI score was comparable (HCV+, 12.1, vs. HCV-negative, 11.8, p = .37). In the HCV+ group, donors were older (33 vs. 31 years, p < .001). Ischemic time of donor hearts (3.48 vs. 3.28 h, p < .001) and travel distance (250 vs. 157 miles, p < .001) were longer in HCV+ group. In the Kaplan Meier analysis with a median follow-up of 750 days, survival was comparable between the two groups (2-year survival, MELD-XI Low: HCV+, 92.4 ± 3.6% vs. HCV-negative, 91.1 ±.8%, p = .83, Medium: HCV+ 89.2 ± 4.3% vs. HCV-negative, 88.2 ± 1.0%, p = .68, and High: HCV+, 84.9 ± 4.5% vs. HCV-negative, 84.6 ± 1.1%, p = .75) In multivariate Cox hazard models, HCV donors were not associated with mortality in each MELD-XI subgroup (Low: adjusted hazard ratio (aHR), 1.02, p = .94; Medium: aHR, .95, p = .81; and High: aHR, .93, p = .68).

CONCLUSION

Utilization of HCV+ hearts was not associated with an increased risk of adverse outcomes in recipients with an elevated MELD- XI score.

Hepatitis C and heart transplantation: An update

There are limited data regarding heart transplantation in the setting of hepatitis C virus (HCV) infection in either recipients or donors, as the practice was infrequent, given concerns of worse post-transplant outcomes. This changed dramatically after the development of highly effective HCV therapies, namely direct-acting antivirals (DAAs). Additionally, nucleic acid testing currently in use establishes more precisely the risk of HCV transmission from donors. As a result, chronic HCV infection in itself is no longer a barrier for heart transplant candidates, and the use of HCV-positive organs for HCV-infected and non-infected transplant candidates has increased dramatically. A review of the literature revealed that in the pre-DAA era, HCV seropositive heart transplant patients had a higher mortality than their seronegative counterparts. However, short-term data suggest that the differences in survival have been erased in the DAA era. Heart transplantation from HCV-viremic donors to HCV-uninfected recipients has become increasingly common as the number of deceased donors with HCV viremia has increased over the past years. Preliminary outcome reports are very encouraging, although further data are needed with regard to long-term safety. New information continues to be incorporated to optimize protocols that guide this practice.

The Association of the UNOS Heart Allocation Policy Change With Transplant and Left Ventricular Assist Device Access and Outcomes

In October 2018, the allocation policy for adult orthotopic heart transplant (OHTx) in the United States was changed, with the goal of reducing waitlist mortality and providing broader sharing of donor organs within the United States. This study aimed to assess the association of this policy change with changes in access to OHTx versus left ventricular assist devices (LVADs), overall and in key sociodemographic subgroups, in the United States from 2016 to 2019. We identified all patients receiving OHTx or LVAD between 2016 and 2019 using the National Inpatient Sample. Controlling for medical co-morbidities, prepolicy trends, and within-hospital-year effects, we fit a dynamic logistic regression model to evaluate patient and hospital factors associated with receiving OHTx versus LVAD before versus after policy change. We also examined the frequency of temporary mechanical circulatory support in the same fashion. We identified 2,264 patients who received OHTx and 3,157 who received LVADs during the study period. In its first year of implementation, the United Network for Organ Sharing policy change of 2018 was associated with no overall change utilization of OHTx versus LVAD. In OHTx recipients, the frequency of use of temporary mechanical circulatory support changed from 15.6% in the before period to 42.6% in the after period (p <0.001). Although the policy change was associated with differences in the odds of receiving an OHTx versus LVAD between different regions of the country, there were no significant changes based on age, gender, race/ethnicity, insurance status, or rurality. In conclusion, the United Network for Organ Sharing policy change on access to OHTx was associated with no overall change in OHTx versus LVAD use in its first year of implementation although we observed small changes in relative odds of transplant based on rurality. Shifts in regional allocation were not significant overall, although certain regions appeared to have a relative increase in their use of OHTx.

Covid-19 positive donor utilization for heart transplantation: The new frontier for donor pool expansion

BACKGROUND

Hearts from COVID-19 positive donors (CPD) are being utilized for heart transplantation by some centers; however, this is in the setting of the lack of guidelines or robust evidence. The paucity of evidence is reflected in the recent Organ Procurement and Transplantation Network (OPTN) communication describing CPD utilization as an "unknown risk."

METHODS AND RESULTS

We analyzed the UNOS database for adult heart transplants performed between January 2021 to December 2022, and CPD comprised of a significant percentage of donors, being used in >10% of recipients in some UNOS regions. Between July 2022 and December 2022, 7.9% of heart transplants were with CPD, and in the same period Hepatitis C positive donors accounted for 7.1% and donation after circulatory death (DCD) accounted for 10.3%.

CONCLUSION

If the transplant community comes up with a standardized approach and guidance in using CPD hearts, this could provide an effective donor pool expansion strategy.

The Cost-effectiveness of Transplanting Hearts From Hepatitis C-infected Donors Into Uninfected Recipients

BACKGROUND

The DONATE HCV trial demonstrated the safety and efficacy of transplanting hearts from hepatitis C viremic (HCV+) donors. In this report, we examine the cost-effectiveness and impact of universal HCV+ heart donor eligibility in the United States on transplant waitlist time and life expectancy.

METHODS

We developed a microsimulation model to compare 2 waitlist strategies for heart transplant candidates in 2018: (1) status quo (SQ) and (2) SQ plus HCV+ donors (SQ + HCV). From the DONATE HCV trial and published national datasets, we modeled mean age (53 years), male sex (75%), probabilities of waitlist mortality (0.01-0.10/month) and transplant (0.03-0.21/month) stratified by medical urgency, and posttransplant mortality (0.003-0.052/month). We assumed a 23% increase in transplant volume with SQ + HCV compared with SQ. Costs (2018 United States dollar) included waitlist care ($2200-190 000/month), transplant ($213 400), 4-wk HCV treatment ($26 000), and posttransplant care ($2500-11 300/month). We projected waitlist time, quality-adjusted life-years (QALYs), lifetime costs, and incremental cost-effectiveness ratios (ICERs [$/QALY, discounted 3%/year]; threshold ≤$100 000/QALY).

RESULTS

Compared with SQ, SQ + HCV decreased waitlist time from 8.7 to 6.7 months, increased undiscounted life expectancy from 8.9 to 9.2 QALYs, and increased discounted lifetime costs from $671 400/person to $690 000/person. Four-week HCV treatment comprised 0.5% of lifetime costs. The ICER of SQ + HCV compared with SQ was $74 100/QALY and remained ≤$100 000/QALY with up to 30% increases in transplant and posttransplant costs.

CONCLUSIONS

Transplanting hearts from HCV-infected donors could decrease waitlist times, increase life expectancy, and be cost-effective. These findings were robust within the context of current high HCV treatment costs.

Temporal changes in the utilization of kidneys from hepatitis C virus-infected donors in the United States

Despite data demonstrating increased utilization of kidneys from hepatitis C virus (HCV)-infected donors, it is unknown whether this is due to an increase in the donor pool or improved organ utilization and whether data from early pilot trials were temporally associated with changes in organ utilization. We used data from the Organ Procurement and Transplantation Network on all kidney donors and recipients of kidney transplants from January 1, 2015, to March 31, 2022 to evaluate temporal changes using joinpoint regression. Our primary analyses compared donors on the basis of their HCV viremic status (HCV-infected vs HCV-negative). Kidney utilization changes were assessed by evaluating the kidney discard rate and kidneys transplanted per donor. A total of 81 833 kidney donors were included in the analysis. There was a statistically significant decrease in the discard rates of HCV-infected kidney donors from 40% to just over 20% over a 1-year period, with a concurrent increase in kidneys transplanted per donor. This increased utilization occurred in tandem with the publication of pilot trials involving HCV-infected kidney donors in HCV-negative recipients rather than an increase in the donor pool. Ongoing clinical trials may strengthen existing data, which could result in this practice becoming the accepted standard of care.

A Retrospective Evaluation of Changing Health Characteristics Amongst Deceased Organ Donors in the United States

BACKGROUND

The availability of suitable donor organs remains a limiting factor to performing life-saving transplant operations. This study evaluates changes in the health of the donor population and its influence on organ use in the United States.

METHODS

A retrospective analysis was performed using the OPTN STAR data file from 2005 to 2019. Three donor eras were defined: 1) 2005 to 2009, 2) 2010 to 2014, and 3) 2015 to 2019. The primary outcome was donor use, defined as transplantation of at least one solid organ. Descriptive analyses were performed, and associations of donor use were examined with multivariable logistic regression models. P values <.01 were considered significant.

RESULTS

The cohort included 132,783 potential donors of which 124,729 (93.9%) were used for transplantation. Donor median age was 42 years (interquartile range 26-54), 53,566 (40.3%) were female, and 88,209 (66.4%) were White, 21,834 (16.4%) were black, and 18,509 (13.9%) were Hispanic. Compared with donors from Eras 1 and 2, donors in Era 3 were younger (P < .001), had higher body mass index (BMI) (P < .001), increased rates of diabetes mellitus (DM) (P < .001), hepatitis C virus (HCV) positivity (P < .001) and more comorbidities (P < .001). Multivariable modeling found donor BMI, DM, hypertension, and HCV status as health factors significantly associated with donor use. Compared with Era 1, there was increased use in Era 3 of donors with BMI ≥30 kg/m², DM, hypertension, HCV-positive status, and donors with ≥3 comorbidities.

CONCLUSIONS

Despite an increasing prevalence of chronic health problems in the donor population, donors with multiple comorbid conditions are more likely to be used for transplantation in recent years.

Expanding heart transplantation in 2022 and beyond

PURPOSE OF REVIEW

Despite advances in the technology of mechanical circulatory support, the need for heart transplantation continues to grow. The longevity of heart transplants continues to be superior to mechanical solutions, though the short-term differences are shrinking. In this review, we cover three timely developments and summarize the recent literature.

RECENT FINDINGS

After stagnant rates of heart transplant activity for some years, recently, transplant volume has increased. The developments that have ignited interest have been the use of hepatitis C infected donors, which can now be safely transplanted with the advent of curative oral regimens, and the worldwide use of donors following withdrawal of life support as opposed to traditional brain death donors. In addition, the recent experience of human cardiac xenotransplantation has been very exciting, and though it is not of clinical utility yet, it holds the promise for a virtually unlimited supply of organs at some time in the future.

SUMMARY

Much work remains to be done, but together, all three of these developments are exciting and important to be aware of in the future. Each will contribute to additional donors for human heart transplantation and hopefully will alleviate suffering and death on the waiting list.

Outcomes following heart or bilateral-lung transplantation from donors who died of drug toxicity in British Columbia, Canada

INTRODUCTION

The illicit drug toxicity (overdose) crisis has worsened across Canada; between 2016 and 2021, more than 28,000 individuals have died of drug toxicity. Organ donation from persons who experience drug toxicity death (DTD) has increased in recent years. This study examines whether survival after heart or bilateral-lung transplantation differed by donor cause of death.

METHODS

We studied transplant recipients in British Columbia who received heart (N = 110) or bilateral-lung (N = 223) transplantation from deceased donors aged 12-70 years between 2013 and 2019. Transplant recipient survival was compared by donor cause of death from drug toxicity or other. Five-year Kaplan-Meier estimates of survival and 3-year inverse probability treatment weighted Cox proportional hazards models were conducted.

RESULTS

DTD donors made up 36% (40/110) of heart and 24% (54/223) of bilateral-lung transplantations. DTD donors were more likely to be young, white, and male. Unadjusted 5-year recipient survival was similar by donor cause of death (heart: 87% for DTD and 86% for non-DTD, p = .75; bilateral- lung: 80% for DTD and 76% for non-DTD, p = .65). Adjusted risk of mortality at 3-years post-transplant was similar between recipients of DTD and non-DTD donor heart (hazard ratio [HR]: .94, 95% confidence interval (CI): .22-4.07, p = .938) and bilateral-lung (HR: 1.06, 95% CI: .41-2.70, p = .908).

CONCLUSION

Recipient survival after heart or bilateral-lung transplantation from DTD donors and non-DTD donors was similar. Donation from DTD donors is safe and should be considered more broadly to increase organ donation.

Accelerated Cardiac Allograft Vasculopathy in an Orthotopic Heart Transplant Recipient with Prior COVID-19

BACKGROUND Cardiac allograft vasculopathy (CAV) is a post-orthotopic heart transplant (OHT) complication driven by intimal smooth muscle proliferation and immune hyperactivity to donor heart tissue. Accelerated CAV leads to allograft failure within 1 year after receiving a normal angiogram result. Viruses can contribute to CAV development, but CAV after SARS-CoV-2 infection has not been reported to date. CASE REPORT A 48-year-old man, 5 years after OHT for non-ischemic cardiomyopathy, was admitted to the Cardiac Care Unit with 3 days of abdominal pain, dyspnea, and palpitations. His medical history included hyperlipidemia and insulin-dependent diabetes. He was compliant with all medications. Two months prior, he had a mild COVID-19 case. An echocardiogram and coronary angiogram 6 and 9 months prior, respectively, were unremarkable. Right and left heart catheterization demonstrated increased filling pressures, a cardiac index of 1.7 L/ml/m², and diffuse vasculopathy most severe in the LAD artery. Flow could not be restored despite repeated ballooning and intra-catheter adenosine. Empiric ionotropic support, daily high-dose methylprednisolone, and plasmapheresis were started. A few days later, the patient had cardiac arrest requiring venoarterial extracorporeal membranous oxygenation. Given CAV's irreversibility, re-transplantation was considered, but the patient had an episode of large-volume hemoptysis and remained clinically unstable for transplant. The patient died while on palliative care. CONCLUSIONS Our patient developed accelerated CAV 2 months after having COVID-19. While CAV has known associations with certain viruses, its incidence after SARS-CoV-2 infection is unknown. Further research is needed to determine if prior SARS-CoV-2 infection is a risk factor for development of CAV in OHT recipients.

Outcomes of Over 1000 Heart Transplants Using Hepatitis C-Positive Donors in the Modern Era

BACKGROUND

Advances in hepatitis C virus (HCV) treatment and the ongoing opioid epidemic have made HCV-positive donors increasingly available for heart transplantation (HT). This analysis reports outcomes of over 1000 HCV-positive HTs in the United States in the modern era.

METHODS

The United Network of Organ Sharing registry was used to identify HTs between 2015 and 2021. Recipients were grouped by donor HCV status and by nucleic acid amplification test (NAT) positivity. The primary outcome was 1-year mortality, and secondary outcomes included 3-year mortality. A subanalysis compared HCV-positive HT outcomes between NAT-positive and NAT-negative donors. Risk adjustment was performed using Cox regression. Kaplan-Meier analysis was used to estimate survival.

RESULTS

The frequency of HCV-positive HT increased from 0.12% of HTs in 2015 to 12.9% in 2021 (P < .001). Of 16,648 HTs, 1170 (7.0%) used an organ from an HCV-positive donor. Recipients of HCV-positive organs were more likely to be HCV seropositive, older, and White. Unadjusted 1- and 3-year survival rates were not significantly different between recipients of HCV-negative and HCV-positive organs. After risk adjustment HCV-positive donor status was not associated with an elevated risk for 1-year (hazard ratio, 0.92; 95% CI, 0.71-1.19; P = .518) or 3-year mortality. Among HCV-positive HTs 772 (61.7%) were NAT positive. After risk adjustment NAT positivity did not impact 1-year mortality.

CONCLUSIONS

The proportion of HCV-positive HTs has increased over 100-fold in recent years. This analysis of the US experience demonstrates that recipients of HCV-positive hearts, including those that are NAT positive, have acceptable outcomes with similar early to midterm survival as recipients of HCV-negative organs.

The impact of the United Network of Organ Sharing allocation change on waitlist trajectories of inpatients listed with inotropic support: A single-center analysis

BACKGROUND

In the United Network of Organ Sharing (UNOS) allocation scheme prior to October 18, 2018, heart transplant (HTx) candidates with extracorporeal membrane oxygenation (ECMO), temporary mechanical circulatory support (MCS), or pulmonary artery (PA) catheter inotropic support all received Status 1A priority. In revised scheme, patients with PA catheter and inotropic support are Status 3 after those on ECMO (Status 1) or temporary MCS (Status 2). We examined the impact of the allocation change on HTx candidates listed Status 1A versus Status 3 at a high-volume transplant center.

METHODS

Between January 2017 and January 2021, 75 patients were listed with a PA catheter and inotropic support prior to the allocation change (Era 1) and 48 were listed after (Era 2). Clinical characteristics and outcomes were compared for these 123 patients.

RESULTS

Heart transplant (HTx) candidates in Era 2 had higher median inotrope doses at listing. There was no significant difference in inpatient wait list days (12 vs. 20 days, P = .15), transition to temporary MCS (33.3% vs. 22.7%, P = .15), or wait list mortality (6.3% vs. 4.0%, P = .68). There was also no significant difference in survival to transplantation (91.7% vs. 94.7%, P = .71). There were no differences in post-transplant outcomes including 1-year survival (88.6% vs. 93.0%, P = .38).

CONCLUSION

At a high-volume transplant center, the UNOS allocation change did not result in increased wait list time, use of temporary MCS, or mortality on the waitlist or post-transplant for candidates on inotropic support with continuous hemodynamic monitoring.

Trends in cardiovascular medicine: Update on cardiac transplantation

Advanced heart failure affects more than 250,000 people in the United States alone and is associated with high risk of morbidity and mortality. Cardiac transplantation provides a cure for patients with advanced disease but has historically been limited by donor availability. Recent changes in the allocation system as well as advances in donor selection, procurement and desensitization protocols have served to widen the donor pool and increase the availability of cardiac transplantation for those in need. This review provides an update on recent advances in cardiac transplantation.

Review of heart transplantation from hepatitis C-positive donors

Significant scarcity of a donor pool exists for heart transplantation (HT) as the prevalence of patients with end-stage refractory heart failure is increasing exceptionally. With the discovery of effective direct-acting antiviral and favorable short-term outcomes following HT, the hearts from hepatitis C virus (HCV) patient are being utilized to increase the donor pool. Short-term outcomes with regards to graft function, coronary artery vasculopathy, and kidney and liver disease is comparable in HCV-negative recipients undergoing HT from HCV-positive donors compared to HCV-negative donors. A significant high incidence of donor-derived HCV transmission was observed with great success of achieving sustained viral response with the use of direct-acting antivirals. By accepting HCV-positive organs, the donor pool has expanded with younger donors, a shorter waitlist time, and a reduction in waitlist mortality. However, the long-term outcomes and impact of specific HCV genotypes remains to be seen. We reviewed the current literature on HT from HCV-positive donors.

Long-term follow-up of acute and chronic rejection in heart transplant recipients from hepatitis C viremic (NAT+) donors

The long-term safety of heart transplants from hepatitis C viremic (NAT+) donors remains uncertain. We conducted a prospective study of all patients who underwent heart transplantation at our center from January 2018 through August 2020. Routine testing was performed to assess for donor-derived cell-free DNA, acute cellular rejection (ACR), antibody-mediated rejection (AMR), and cardiac allograft vasculopathy (CAV). Allograft dysfunction and mortality were also monitored. Seventy-five NAT- recipients and 32 NAT+ recipients were enrolled in the study. All NAT+ recipients developed viremia detected by PCR, were treated with glecaprevir/pibrentasvir at the time of viremia detection, and cleared the virus by 59 days post-transplant. Patients who underwent NAT testing starting on post-operative day 7 (NAT+ Group 1) had significantly higher viral loads and were viremic for a longer period compared with patients tested on post-operative day 1 (NAT+ Group 2). Through 3.5 years of follow-up, there were no statistically significant differences in timing, severity, or frequency of ACR in NAT+ recipients compared with the NAT- cohort, nor were there differences in noninvasive measures of graft injury, incidence or severity of CAV, graft dysfunction, or mortality. There were five episodes of AMR, all in the NAT- group. There were no statistically significant differences between Group 1 and Group 2 NAT+ cohorts. Overall, these findings underscore the safety of heart transplantation from NAT+ donors.

Association of Donors With US Public Health Service Risk Criteria and Outcomes After Adult vs Pediatric Cardiac Transplant

Importance

The United Network for Organ Sharing (UNOS) evaluates donor risk for acute transmission of HIV, hepatitis B, or hepatitis C based on US Public Health Services (PHS)-specific criteria. However, recent data regarding use and outcomes of those donors with PHS risk criteria among pediatric and adult heart transplant recipients are lacking.

Objective

To compare use and outcomes of graft from donors with PHS risk criteria vs those with a standard-risk donor (SRD) in children vs adults in a contemporary cohort.

Design, Setting, and Participants

This cohort was a nationwide analysis of heart transplants in the US that used data from the UNOS database. Participants were children (<18 years old) and adults (≥18 years old) who received a heart transplant from January 1, 2010, to December 31, 2021.

Exposures

UNOS-defined donor risk status.

Main Outcomes and Measures

Trend analysis compared changes in PHS risk criteria use among children and adults. Patient survival was analyzed using Kaplan-Meier curves with log rank and Cox proportional hazards to compare PHS risk-criteria outcomes vs SRD-criteria outcomes in children and adult heart transplant recipients. Additional analysis was performed among adults who received a PHS-risk criteria graft that was previously declined for pediatric recipients.

Results

Of 5115 pediatric transplant recipients (donor without PHS risk median [IQR] age, 5 [0-13] years and donor with PHS risk median [IQR] age, 8 [0-14] years) and 30 289 adult heart transplant recipients (donor without PHS risk median [IQR] age, 56 [46-63] years and donor with PHS risk median [IQR] age, 57 [47-63] years), PHS risk criteria comprised 8% in children vs 25% in adults. PHS criteria are being increasingly used over the past decade with the proportion of recipients transplanted with PHS risk-criteria donors being approximately 3 times greater among adult recipients than children recipients. Pediatric recipients of a PHS risk-criteria donor had greater pretransplant ventilatory support, whereas adult recipients of a PHS risk-criteria donor had greater pretransplant extracorporeal membrane oxygenation use. Patient survival was similar between pediatric recipients of PHS risk-criteria grafts vs SRD-criteria grafts and slightly higher among adult recipients of PHS risk-criteria grafts vs SRD-criteria grafts. The 1778 adult recipients who received a PHS criteria-risk donor that was previously declined for pediatric recipients had similar patient survival recipients compared with SRD-criteria donors (HR, 0.92; 95% CI, 0.81-1.03; P = .18).

Conclusions and Relevance

In the current era, a 3-fold greater proportion of adult recipients receive a PHS risk-criteria graft compared with children despite similar posttransplant patient survival. The ongoing organ donor shortage underscores the need for consideration of PHS risk criteria where these donors remain underused.

Strategies for Expanding Donors Pool in Heart Transplantation

Heart transplant remains the criterion standard treatment for patients in end-stage heart failure. Improvement in the post-heart transplant outcomes in the last decade has contributed to increased demand for organs. Worldwide each year, more than 5000 heart transplants are performed and 50,000 people become candidates for heart transplant. In the last 50 years, there have been several attempts to expand donor criteria to increase the donor pool. Despite making hepatitis C virus, opioid overdose death, old age allowable and changing the allocation system, the gap between supply and demand is widening and unfortunately, thousands die every year waiting due to the critical shortage of organs. New technologies for heart donation after circulatory death have emerged, particularly normothermic regional organ perfusion and ex-vivo heart perfusion using organ care systems. However, these technologies still do not fill the gap. Continuous advancements in areas such as regenerative medicine and xenotransplantation, among others, are needed to overcome the shortage of heart donors for heart transplantation.

Approaches and strategies to manage the hepatitis C virus-positive heart donor

PURPOSE OF REVIEW

Cardiac transplantation remains the treatment of choice for patients with advanced heart failure, but is limited by a donor organ shortage. Utilization of hepatitis C virus (HCV)-positive donors has been recently adopted to expand access to heart transplantation. We review the history of HCV heart transplantation, modern drug therapy, and recent outcomes.

RECENT FINDINGS

Since the advent of direct-acting antiviral (DAA) therapy, several single-center studies, and retrospective reviews have demonstrated good short-term outcomes, shorter waitlist times, and clearance of viremia with recipients of HCV-positive hearts. Two principle approaches to treatment of recipients of HCV viremic donors are utilized. In the prophylactic strategy, therapy is initiated before viremia is detected compared with the preemptive approach where initiation of DAA is delayed until after viremia is detected. Future studies are needed to address uncertainty about medium and long-term outcomes of using HCV-positive hearts and to determine the optimal treatment timing and duration.

SUMMARY

Utilization of HCV-positive donors has expanded the heart donor pool and appears safe through the early posttransplant period. We suggest that prophylactic administration of the shortest effective course of a DAA pangenotypic agent should be the current standard of care.

Expanding Selection Criteria to Repairable Diseased Hearts to Meet the Demand of Shortage of Donors in Heart Transplantation

Heart transplant surgery is considered the destination therapy for end-stage heart disease. Unfortunately, many patients in the United States of America who are eligible candidates for transplants cannot undergo surgery due to donor shortage. In addition, some donors' hearts are being labeled as unacceptable for transplant surgery because of the rigorous and restricted rules placed on the approval process of using a donor's heart. Over the last few decades, the rising discrepancy between the scarcity of donor hearts and the demand for such organs has led to the discussion of expanding the donor heart selection criteria. A softer view on using marginal hearts for transplants would help those on the waitlist to receive a heart transplant. Marginal hearts that contain the hepatitis c virus (HCV), COVID-19, older age, or repairable heart defects have become viable options to use for a heart transplant. Also, the prioritization based on the new heart allocation system would help efficiently decide which recipients would be the first to get a donor's heart. Recently there has been a consensus to broaden the eligibility of donor's hearts by accepting valvular abnormalities, coronary artery disease, and congenital abnormalities. This review highlights some of those expansions in selection criteria in particular using repairable hearts, which could be fixed in the operating room on the back table before transplantation.

Viral hepatitis: Past, present, and future

Each hepatitis virus-Hepatitis A, B, C, D, E, and G-poses a distinct scenario to the patient and clinician alike. Since the discovery of each virus, extensive knowledge regarding epidemiology, virologic properties, and the natural clinical and immunologic history of acute and chronic infections has been generated. Basic discoveries about host immunologic responses to acute and chronic viral infections, combined with virologic data, has led to vaccines to prevent Hepatitis A, B, and E and highly efficacious antivirals for Hepatitis B and C. These therapeutic breakthroughs are transforming the fields of hepatology, transplant medicine in general, and public and global health. Most notably, there is even an ambitious global effort to eliminate chronic viral hepatitis within the next decade. While attainable, there are many barriers to this goal that are being actively investigated in basic and clinical labs on the local, national, and international scales. Herein, we discuss pertinent clinical information and recent organizational guidelines for each of the individual hepatitis viruses while also synthesizing this information with the latest research to focus on exciting future directions for each virus.

Evolving Characteristics of Heart Transplantation Donors and Recipients: JACC Focus Seminar

Although the burden of end-stage heart failure continues to increase, the number of available organs for heart transplantation (HT) remains inadequate. The HT community has been challenged to find ways to expand the number of donor hearts available. Recent advances include use of hearts from donors infected with hepatitis C virus as well as other previously underutilized donors, including those with left ventricular dysfunction, of older age, and with a history of cocaine use. Concurrently, emerging trends in HT surgery include donation after circulatory death, ex vivo normothermic heart perfusion, and controlled hypothermic preservation, which may enable procurement of organs from farther distances and prevent early allograft dysfunction. Contemporary HT recipients have also evolved in light of the 2018 revision to the U.S. heart allocation policy. This focus seminar discusses recent trends in donor and recipient phenotypes and management strategies for successful HT, as well as evolving areas and future directions.

Patient selection for heart transplant: balancing risk

PURPOSE OF REVIEW

Heart failure incidence continues to rise despite a relatively static number of available donor hearts. Selecting an appropriate heart transplant candidate requires evaluation of numerous factors to balance patient benefit while maximizing the utility of scarce donor hearts. Recent research has provided new insights into refining recipient risk assessment, providing additional tools to further define and balance risk when considering heart transplantation.

RECENT FINDINGS

Recent publications have developed models to assist in risk stratifying potential heart transplant recipients based on cardiac and noncardiac factors. These studies provide additional tools to assist clinicians in balancing individual risk and benefit of heart transplantation in the context of a limited donor organ supply.

SUMMARY

The primary goal of heart transplantation is to improve survival and maximize quality of life. To meet this goal, a careful assessment of patient-specific risks is essential. The optimal approach to patient selection relies on integrating recent prognostication models with a multifactorial assessment of established clinical characteristics, comorbidities and psychosocial factors.

Hepatitis C Virus Treatment and Solid Organ Transplantation

Hepatitis C virus (HCV) infection is a common indication for liver transplantation. If the patient's HCV is untreated prior to liver transplant, infection of the allograft is nearly universal and can lead to graft failure. The demand for deceased-donor organ transplantation continues to surpass the available supply of donor organs. Waitlist mortality remains an important concern, and several strategies have been enacted to increase organ supply, such as using high-risk donors, including those who are HCV positive. The development of safe and highly effective HCV therapy with direct-acting antiviral agents has revolutionized the management of liver transplant candidates and transplantrecipients. Moreover, thenewer antiviral therapieshave paved the road for use of HCV-viremic organs, effectively expanding the donor pool and changing the landscape of solid organ transplantation. This article reviews the data on HCV treatment prior to and after organ transplantation.

National trends and outcomes of Heart-kidney transplantation using hepatitis c positive donors

BACKGROUND

This study evaluated the outcomes of combined heart-kidney transplantation in the United States using hepatitis C positive (HCV+) donors.

METHODS

Adults undergoing combined heart-kidney transplantation from 2015 to 2020 were identified in the United Network for Organ Sharing registry. Patients were stratified by donor HCV status. Kaplan-Meier curves were created with multivariable Cox regression models used for risk-adjustment in a propensity-matched cohort.

RESULTS

A total of 950 patients underwent heart-kidney transplantation of which 7.8% (n = 75) used HCV+ donors; 68% (n = 51) were viremic and 32% (n = 24) were non-viremic donors. Unadjusted 1-year recipient survival was similar between HCV+ versus HCV- donors (84 vs 88%, respectively; p = 0.33). Risk-adjusted analysis in the propensity-matched cohort showed HCV+ donor use did not confer increased risk of 1-year mortality (hazard ratio 0.63, 95% CI 0.17-2.32; p = 0.49). Sub-group analysis showed viremic and non-viremic HCV+ donors had similar 1-year survival as well (84 vs 84%; p = 0.95).

CONCLUSIONS

Compared with recipients of HCV- donor dual heart-kidney transplants, recipients of HCV+ organs had comparable 1-year survival and clinical outcomes after combined transplantation. Although future studies should evaluate other outcomes related to HCV+ donor use, this practice appears safe and should be expanded further in the heart-kidney transplant population. This article is protected by copyright. All rights reserved.

Caregiver exposure to hepatitis C virus following transplantation with hepatitis C viremic donor organs: A case series

INTRODUCTION

Direct acting antiviral (DAA) therapeutics have ushered in an era in which transplanting organs from donors infected with hepatitis C virus (HCV+) into recipients without (HCV-) is an increasingly common practice. Rare but potentially life-threatening events have been reported in recipients of HCV+ organs.

METHODS

Since 2018 at our institution, 182 HCV- patients have received HCV+ donor organs. Here, we retrospectively reviewed cases in which recipients' family member caregivers reported sustaining needlestick exposures at home following discharge of the transplant recipient from the hospital.

RESULTS

Caregiver needlestick exposures were passively reported in three cases of HCV+ into HCV- transplants (1.64% of such cases at our center). In all instances, the exposed individuals were aiding in diabetic management and the exposure occurred via lancets or insulin needles. In one case, the recipient viral load was undetectable at the time of the exposure but in the other two, recipients were viremic, putting their family members at risk to contract HCV infection. Surveillance for the exposed individuals was undertaken and no transmissions occurred.

DISCUSSION

For centers performing HCV+ into HCV- transplants, it is important that informed consent includes discussion of potential secondary risks to family members and caregivers. Further, protocols for post-exposure surveillance and for the acquisition of DAA treatment in the event of a secondary transmission should be in place. This article is protected by copyright. All rights reserved.