Differences in Donor Heart Acceptance by Race and Gender of Patients on the Transplant Waiting List

Importance

Barriers to heart transplant must be overcome prior to listing. It is unclear why Black men and women remain less likely to receive a heart transplant after listing than White men and women.

Objective

To evaluate whether race or gender of a heart transplant candidate (ie, patient on the transplant waiting list) is associated with the probability of a donor heart being accepted by the transplant center team with each offer.

Design, Setting, and Participants

This cohort study used the United Network for Organ Sharing datasets to identify organ acceptance with each offer for US non-Hispanic Black (hereafter, Black) and non-Hispanic White (hereafter, White) adults listed for heart transplant from October 18, 2018, through March 31, 2023.

Exposures

Black or White race and gender (men, women) of a heart transplant candidate.

Main Outcomes and Measures

The main outcome was heart offer acceptance by the transplant center team. The number of offers to acceptance was assessed using discrete time-to-event analyses, nonparametrically (stratified by race and gender) and parametrically. The hazard probability of offer acceptance for each offer was modeled using generalized linear mixed models adjusted for candidate-, donor-, and offer-level variables.

Results

Among 159 177 heart offers with 13 760 donors, there were 14 890 candidates listed for heart transplant; 30.9% were Black, 69.1% were White, 73.6% were men, and 26.4% were women. The cumulative incidence of offer acceptance was highest for White women followed by Black women, White men, and Black men (P < .001). Odds of acceptance were less for Black candidates than for White candidates for the first offer (odds ratio [OR], 0.76; 95% CI, 0.69-0.84) through the 16th offer. Odds of acceptance were higher for women than for men for the first offer (OR, 1.53; 95% CI, 1.39-1.68) through the sixth offer and were lower for the 10th through 31st offers.

Conclusions and Relevance

The cumulative incidence of heart offer acceptance by a transplant center team was consistently lower for Black candidates than for White candidates of the same gender and higher for women than for men. These disparities persisted after adjusting for candidate-, donor-, and offer-level variables, possibly suggesting racial and gender bias in the decision-making process. Further investigation of site-level decision-making may reveal strategies for equitable donor heart acceptance.

Eligibility and Projected Benefits of Rapid Initiation of Quadruple Medical Therapy for Newly Diagnosed Heart Failure

BACKGROUND

U.S. nationwide estimates of the proportion of patients newly diagnosed with heart failure with reduced ejection fraction (HFrEF) eligible for quadruple medical therapy, and the associated benefits of rapid implementation, are not well characterized.

OBJECTIVES

This study sought to characterize the degree to which patients newly diagnosed with HFrEF are eligible for quadruple medical therapy, and the projected benefits of in-hospital initiation.

METHODS

Among patients hospitalized for newly diagnosed HFrEF in the Get With The Guidelines-Heart Failure registry from 2016 to 2023, eligibility criteria based on regulatory labeling, guidelines, and expert consensus documents were applied for angiotensin receptor-neprilysin inhibitor, beta-blocker, mineralocorticoid receptor antagonist, and sodium-glucose cotransporter 2 inhibitor therapies. Of those eligible, the projected effect of quadruple therapy on 12-month mortality was modeled using treatment effects from pivotal clinical trials utilized by the AHA/ACC/HFSA Guideline for the Management of Heart Failure, and compared with observed outcomes among patients treated with angiotensin-converting enzyme inhibitor/angiotensin receptor blocker and beta-blockers.

RESULTS

Of 33,036 patients newly diagnosed with HFrEF, 27,158 (82%) were eligible for quadruple therapy, and 30,613 (93%) were eligible for ≥3 components. From 2021 to 2023, of patients eligible for quadruple therapy, 15.3% were prescribed quadruple therapy and 41.5% were prescribed triple therapy. Among Medicare beneficiaries eligible for quadruple therapy, 12-month incidence of mortality was 24.7% and HF hospitalization was 22.2%. Applying the relative risk reductions in clinical trials, complete implementation of quadruple therapy by time of discharge was projected to yield absolute risk reductions in 12-month mortality of 10.4% (number needed to treat = 10) compared with angiotensin-converting enzyme inhibitor/angiotensin receptor blocker and beta-blocker, and 24.8% (number needed to treat = 4) compared with no GDMT.

CONCLUSIONS

In this nationwide U.S. cohort of patients hospitalized for newly diagnosed HFrEF, >4 of 5 patients were projected as eligible for quadruple therapy at discharge; yet, <1 in 6 were prescribed it. If clinical trial benefits can be fully realized, in-hospital initiation of quadruple medical therapy for newly diagnosed HFrEF would yield large absolute reductions in mortality.

Racial and Ethnic Disparities in Ambulatory Heart Failure Ventricular Assist Device Implantation and Survival

BACKGROUND

Durable left ventricular assist devices (VADs) improve survival in eligible patients, but allocation has been associated with patient race in addition to presumed heart failure (HF) severity.

OBJECTIVES

This study sought to determine racial and ethnic differences in VAD implantation rates and post-VAD survival among patients with ambulatory HF.

METHODS

Using the INTERMACS (Interagency Registry of Mechanically Assisted Circulatory Support) database (2012-2017), this study examined census-adjusted VAD implantation rates by race, ethnicity, and sex in patients with ambulatory HF (INTERMACS profile 4-7) using negative binomial models with quadratic effect of time. Survival was evaluated using Kaplan-Meier estimates and Cox models adjusted for clinically relevant variables and an interaction of time with race/ethnicity.

RESULTS

VADs were implanted in 2,256 adult patients with ambulatory HF (78.3% White, 16.4% Black, and 5.3% Hispanic). The median age at implantation was lowest in Black patients. Implantation rates peaked between 2013 and 2015 before declining in all demographic groups. From 2012 to 2017, implantation rates overlapped for Black and White patients but were lower for Hispanic patients. Post-VAD survival was significantly different among the 3 groups (log rank P = 0.0067), with higher estimated survival among Black vs White patients (12-month survival: Black patients: 90% [95% CI: 86%-93%]; White patients: 82% [95% CI: 80%-84%]). Low sample size for Hispanic patients resulted in imprecise survival estimates (12-month survival: 85% [95% CI: 76%-90%]).

CONCLUSIONS

Black and White patients with ambulatory HF had similar VAD implantation rates but rates were lower for Hispanic patients. Survival differed among the 3 groups, with the highest estimated survival at 12 months in Black patients. Given higher HF burden in minoritized populations, further investigation is needed to understand differences in VAD implantation rates in Black and Hispanic patients.

Assessing Heuristic Bias During Care for Patients Hospitalized for Heart Failure: Get With The Guidelines-Heart Failure

BACKGROUND

Heuristic biases are increasingly recognized, and potentially modifiable, contributors to patient care and outcomes. Left digit bias is a cognitive bias where continuous variables are categorized by their left-most digit. The impact of this heuristic bias applied to patient age on quality of care in heart failure has not been explored.

METHODS

We examined participants admitted from 2005 to 2021 in the Get With The Guidelines-Heart Failure registry. To create 2 naturally randomized groups, isolating the effect of left digit bias, we dichotomized patients into those discharged within 60 days prior to their 80th birthday (N=4238) and those discharged within 60 days after their 80th birthday (N=4329). We performed multivariable logistic regression to assess the association between discharge date relative to 80th birthday and several in-hospital quality metrics and in-hospital outcomes. Among Medicare participants (N=2759), we performed adjusted Cox regression to analyze the relationship between discharge date and risk of 1-year mortality or readmission.

RESULTS

Among 8567 patients, 50.4% were female, 73% were non-Hispanic White, and 42.9% had an ejection fraction ≤40%. Discharge date relative to 80th birthday was not associated with numerous in-hospital quality metrics or in-hospital outcomes on unadjusted or adjusted logistic regression. Among Medicare beneficiaries, there was no association between discharge date and risk of mortality or readmission at 1-year postdischarge (hazard ratio, 1.03 [95% CI, 0.95-1.12]; P=0.52).

CONCLUSIONS

In a large registry of patients hospitalized for heart failure, we did not detect a left digit bias' with respect to age at discharge, which resulted in differential quality of care or outcomes.

Nurturing Diverse Generations of the Medical Workforce for Success With Authenticity: An Association of Black Cardiologists' Roundtable

The COVID-19 pandemic exposed the consequences of systemic racism in the United States with Black, Hispanic, and other racial and ethnic diverse populations dying at disproportionately higher rates than White Americans. Addressing the social and health disparities amplified by COVID-19 requires in part restructuring of the healthcare system, particularly the diversity of the healthcare workforce to better reflect that of the US population. In January 2021, the Association of Black Cardiologists hosted a virtual roundtable designed to discuss key issues pertaining to medical workforce diversity and to identify strategies aimed at improving racial and ethnic diversity in medical school, graduate medical education, faculty, and leadership positions. The Nurturing Diverse Generations of the Medical Workforce for Success with Authenticity roundtable brought together diverse stakeholders and champions of diversity and inclusion to discuss innovative ideas, solutions, and opportunities to address workforce diversification.

Representation matters: a call for inclusivity and equity in heart failure clinical trials

The burden of heart failure remains substantial worldwide, and heart failure with reduced ejection fraction (HFrEF) affects approximately half of this population. Despite this global prevalence of HFrEF, the majority of contemporary clinical trials in HFrEF have underenrolled individuals from minoritized sex, gender, race, ethnicity, and socioeconomic groups. Moreover, significant disparities in access to HFrEF treatment and outcomes exist across these same strata. We provide a call to action for the inclusion of diverse populations in HFrEF clinical trials; catalogue several barriers to adequate representation in HFrEF clinical trials; and propose strategies to broaden inclusivity in future HFrEF trials.

Circulating microRNAs in cellular and antibody-mediated heart transplant rejection

BACKGROUND

Noninvasive monitoring of heart allograft health is important to improve clinical outcomes. MicroRNAs (miRs) are promising biomarkers of cardiovascular disease and limited studies suggest they can be used to noninvasively diagnose acute heart transplant rejection.

METHODS

The Genomic Research Alliance for Transplantation (GRAfT) is a multicenter prospective cohort study that phenotyped heart transplant patients from 5 mid-Atlantic centers. Patients who had no history of rejection after transplant were compared to patients with acute cellular rejection (ACR) or antibody-mediated rejection (AMR). Small RNA sequencing was performed on plasma samples collected at the time of an endomyocardial biopsy. Differential miR expression was performed with adjustment for clinical covariates. Regression was used to develop miR panels with high diagnostic accuracy for ACR and AMR. These panels were then validated in independent samples from GRAfT and Stanford University. Receiver operating characteristic curves were generated and area under the curve (AUC) statistics calculated. Distinct ACR and AMR clinical scores were developed to translate miR expression data for clinical use.

RESULTS

The GRAfT cohort had a median age of 52 years, with 35% females and 45% Black patients. Between GRAfT and Stanford, we included 157 heart transplant patients: 108 controls and 49 with rejection (50 ACR and 38 AMR episodes). After differential miR expression and regression analysis, we identified 12 miRs that accurately discriminate ACR and 17 miRs in AMR. Independent validation of the miR panels within GRAfT led to an ACR AUC 0.92 (95% confidence interval [CI]: 0.86-0.98) and AMR AUC 0.82 (95% CI: 0.74-0.90). The externally validated ACR AUC was 0.72 (95% CI: 0.59-0.82). We developed distinct ACR and AMR miR clinical scores (range 0-100), a score ≥ 65, identified ACR with 86% sensitivity, 76% specificity, and 98% negative predictive value, for AMR score performance was 82%, 84% and 97%, respectively.

CONCLUSIONS

We identified novel miRs that had excellent performance to noninvasively diagnose acute rejection after heart transplantation. Once rigorously validated, the unique clinical ACR and AMR scores usher in an era whereby genomic biomarkers can be used to screen and diagnose the subtype of rejection. These novel biomarkers may potentially alleviate the need for an endomyocardial biopsy while facilitating the initiation of targeted therapy based on the noninvasive diagnosis of ACR or AMR.

Heart transplantation strategies in arrhythmogenic right ventricular cardiomyopathy: a tertiary ARVC centre experience

Aims

Methods and results

Conclusions

Racial and ethnic disparities in heart failure: current state and future directions

PURPOSE OF REVIEW

This review discusses the current state of racial and ethnic inequities in heart failure burden, outcomes, and management. This review also frames considerations for bridging disparities to optimize quality heart failure care across diverse communities.

RECENT FINDINGS

Treatment options for heart failure have diversified and overall heart failure survival has improved with the advent of effective pharmacologic and nonpharmacologic therapies. With increased recognition, some racial/ethnic disparity gaps have narrowed whereas others in heart failure outcomes, utilization of therapies, and advanced therapy access persist or worsen.

SUMMARY

Racial and ethnic minorities have the highest incidence, prevalence, and hospitalization rates from heart failure. In spite of improved therapies and overall survival, the mortality disparity gap in African American patients has widened over time. Racial/ethnic inequities in access to cardiovascular care, utilization of efficacious guideline-directed heart failure therapies, and allocation of advanced therapies may contribute to disparate outcomes. Strategic and earnest interventions considering social and structural determinants of health are critically needed to bridge racial/ethnic disparities, increase dissemination, and implementation of preventive and therapeutic measures, and collectively improve the health and longevity of patients with heart failure.

Exercise intolerance and rapid skeletal muscle energetic decline in human age-associated frailty

BACKGROUND

Physical frailty in older individuals is characterized by subjective symptoms of fatigue and exercise intolerance (EI). Objective abnormalities in skeletal muscle (SM) mitochondrial high-energy phosphate (HEP) metabolism contribute to EI in inherited myopathies; however, their presence or link to EI in the frail older adult is unknown.

METHODS

Here, we studied 3 groups of ambulatory, community-dwelling adults with no history of significant coronary disease: frail older (FO) individuals (81 ± 2.7 years, mean ± SEM), nonfrail older (NFO) individuals (79 ± 2.0 years), and healthy middle-aged individuals, who served as controls (CONT, 51 ± 2.1 years). Lower extremity SM HEP levels and mitochondrial function were measured with ³¹P magnetic resonance (MR) techniques during graded multistage plantar flexion exercise (PFE). EI was quantified by a 6-minute walk (6MW) and peak oxygen consumption during cardiopulmonary testing (peak VO₂).

RESULTS

During graded exercise, FO, NFO, and CONT individuals all fatigued at similar SM HEP levels, as measured by ³¹P-MR. However, FO individuals fatigued fastest, with several-fold higher rates of PFE-induced HEP decline that correlated closely with shorter exercise duration in the MR scanner and with 6MW distance and lower peak oxygen consumption on cardiopulmonary testing (P < 0.001 for all). SM mitochondrial oxidative capacity was lower in older individuals and correlated with rapid HEP decline but less closely with EI.

CONCLUSION

Several-fold faster SM energetic decline during exercise occurs in FO individuals and correlates closely with multiple measures of EI. Rapid energetic decline represents an objective, functional measure of SM metabolic changes and a potential new target for mitigating frailty-associated physical limitations.

FUNDING

This work was supported by NIH R21 AG045634, R01 AG063661, R01 HL61912, the Johns Hopkins University Claude D. Pepper Older Americans Independence Center P30AG021334, and the Clarence Doodeman Endowment in Cardiology at Johns Hopkins.

Rapid exercise-induced skeletal muscle high-energy phosphate decline occurs in frail, older individuals and is closely linked to exercise intolerance and fatigue.

Dual-Organ Transplantation in a Woman With Right Ventricular Failure Secondary to Arrhythmogenic Right Ventricular Cardiomyopathy

We report a case of a woman with arrhythmogenic right ventricular cardiomyopathy (ARVC) who presented with severe right-sided heart failure and cardiac cirrhosis that mandated heart-liver transplantation. This case highlights an emerging sex-based difference in ARVC where female sex is associated with a higher risk of heart failure than in male patients with ARVC. (Level of Difficulty: Advanced.).

Worldwide disparities in cardiovascular disease: Challenges and solutions

The 20th century saw cardiovascular disease ascend as the leading cause of death in the world. In response to the new challenge that heart disease imposed, the cardiovascular community responded with ground breaking innovations in the form of evidence based medications that have improved survival, imaging modalities that allow for precise diagnosis and guide treatment; revascularization strategies that have not only reduced morbidity, but also improved survival following an acute myocardial infarction. However the benefits have not been distributed equitably and as a result disparities have arisen in cardiovascular care. There is tremendous data from the United States demonstrating the many phenotypical forms of disparities. This paper takes a global view of disparities and highlights that disparate care is not limited to the United States and it is another challenge that the medical community should rise and face head on.