Understanding and Investigating Sex-Based Differences in Heart Transplantation: A Call to Action

Abnormal invasive hemodynamics in heart transplant recipients: A single-center, retrospective study

BACKGROUND

Few studies have quantified invasive hemodynamic parameters in post heart transplant recipients.

AIM

To report the incidence of abnormal hemodynamics in heart transplant recipients at 1-year and 3-year post-transplant and determine if there was any correlation with recipient and donor characteristics.

METHODS

Data from 279 consecutive heart transplant recipients from 2007 through 2020 were analyzed. Clinical variables regarding both recipients and donors as well as hemodynamic variables obtained via right heart catheterization during 1-year and 3-year annual testing were recorded. Simple and multiple linear regression tests were used to determine how recipient and donor variables influenced hemodynamic parameters at 1-year and 3-year.

RESULTS

Data were available for 260 patients and 224 patients at 1-year and 3-year post-transplant respectively. At 1-year, abnormal hemodynamic parameters were common with 24% patients having right atrial pressure (RAP) > 10 mmHg, 52% with mean pulmonary artery pressure > 20 mmHg, and 12% with pulmonary capillary wedge pressure (PCWP) > 18 mmHg. Similar abnormalities were noted at 3-year post-transplant. Recipient body mass index (BMI) demonstrated the strongest correlation with all 3 variables at both 1-year and 3-year by multivariate linear regression analysis (P < 0.001 for both). Both donor age and predicted heart mass difference between recipient and donor were significantly linked to RAP and PCWP at 1-year but did not predict any variables at 3-year post-transplant.

CONCLUSION

Abnormal hemodynamics are common at 1-year and 3-year post-transplant and are associated with recipients with high BMI.

Sex-Based Differences in Early and Late Kidney Outcomes After Heart Transplantation

BACKGROUND

The development of kidney disease after heart transplantation (HT) has been well described and is associated with increased post-HT mortality. Limited data have evaluated sex-based differences in kidney outcomes post-HT.

METHODS

Adults (≥ 18 years old) in the United Network for Organ Sharing registry who underwent HT between 2010 and 2022 were included. Multiorgan transplants were excluded as were patients who required dialysis pre-HT. Baseline characteristics were compared by sex. Outcomes included early kidney failure (need for post-operative dialysis) and late kidney failure (chronic dialysis or kidney transplantation). Multivariable logistic regression was used to determine whether sex predicted development of early kidney failure, and multivariable Cox regression was used to determine whether sex predicted late kidney failure. Outcomes were also compared before and after the 2018 heart-allocation system change.

RESULTS

We included 30,414 HT recipients (n = 8223, 27.0% female); 3535 patients (n = 891, 25% female) developed early kidney failure post-HT. After adjusting for multiple clinical factors, sex was not found to be a significant predictor of early kidney failure post-HT (OR 0.93, 95% CI 0.83-1.04; P = 0.2). Following implementation of the 2018 allocation system, rates of early renal failure increased significantly in both men (10% to 14%; P < 0.001) and women (9% to 13%; P < 0.001), but the effect was similar by sex (P-interaction: > 0.9). Over a median follow-up of 5 years (IQR 2.4-8.0), there were no differences in time to late kidney failure by sex (log rank P = 0.4). After adjustment for various clinical and demographic factors, there was no difference in risk of late kidney failure by sex (aHR 1.11, 95% CI 0.96-1.27; P = 0.2).

CONCLUSIONS

Although sex did not predict the development of early or late kidney failure after HT, future studies are needed to determine sex-specific risk factors for kidney failure and potential preventive strategies.

The Korean Organ Transplant Registry (KOTRY): Third Official Adult Heart Transplant Report

BACKGROUND AND OBJECTIVES

The Korean Organ Transplant Registry (KOTRY) provided data for this third official report on adult heart transplantation (HT), including information from 709 recipients.

METHODS

Data from HTs performed at seven major centers in Korea between March 2014 and December 2020 were analyzed, focusing on immunosuppression, acute rejection, cardiac allograft vasculopathy (CAV), post-transplant survival, and mechanical circulatory support (MCS) usage.

RESULTS

The median ages of the recipients and donors were 56.0 and 43.0 years, respectively. Cardiomyopathy and ischemic heart disease were the most common preceding conditions for HT. A significant portion of patients underwent HT at waiting list status 1 and 0. In the multivariate analysis, a predicted heart mass mismatch was associated with a higher risk of 1-year mortality. Patients over 70 years old had a significantly increased risk of 6-year mortality. The risk of CAV was higher for male donors and donors older than 45 years. Acute rejection was more likely in patients with panel reactive antibody levels above 80%, while statin use was associated with a reduced risk. The employment of left ventricular assist device as a bridge to transplantation increased from 2.17% to 22.4%. Pre-transplant extra-corporeal membrane oxygenation was associated with worse post-transplant survival.

CONCLUSIONS

In this third KOTRY report, we analyzed changes in the characteristics of adult HT recipients and donors and their impact on post-transplant outcomes. The most notable discovery was the increased use of MCS before HT and their impact on post-transplant outcomes.

Highly sensitized patients listed for heart after liver transplantation with or without domino

For patients with end-stage heart disease and borderline hemodynamics, high human leukocyte antigen allosensitization presents a barrier to heart transplantation in a timely manner. Conventional desensitization protocols are inadequate in this context due to time constraints and for the most highly reactive immunologically. We previously reported performing heart after liver transplant with domino liver transplant on a single patient without liver disease. We describe this patient's course to date as well as 4 subsequent patients listed for this novel therapy. This experience demonstrates that the liver effectively confers immunoprotection to the heart for patients with high-titer, preformed antibodies. This strategy may provide some measure of equity for demographic groups previously disadvantaged for heart transplantation due to allosensitization.

Sex and Gender-related Disparities in Clinical Characteristics and Outcomes in Heart Transplantation

PURPOSE OF REVIEW

Limited research has been conducted on sex disparities in heart transplant (HT). The aim of this review is to analyse the available evidence on the influence of sex and gender-related determinants in the entire HT process, as well as to identify areas for further investigation.

RECENT FINDINGS

Although women make up half of the population affected by heart failure and related mortality, they account for less than a third of HT recipients. Reasons for this inequality include differences in disease course, psychosocial factors, concerns about allosensitisation, and selection or referral bias in female patients. Women are more often listed for HT due to non-ischaemic cardiomyopathy and have a lower burden of cardiovascular risk factors. Although long-term prognosis appears to be similar for both sexes, there are significant disparities in post-HT morbidity and causes of mortality (noting a higher incidence of rejection in women and of malignancy and cardiac allograft vasculopathy in men). Additional research is required to gain a better understanding of the reasons behind gender disparities in eligibility and outcomes following HT. This would enable the fair allocation of resources and enhance patient care.

Gender Effect on Clinical Profiles, Pharmacological Treatments and Prognosis in Patients Hospitalized for Heart Failure

Heart failure (HF) is a significant disease affecting 1-2% of the general population. Despite its general aspects, HF, like other cardiovascular diseases, presents various gender-specific aspects in terms of etiology, hemodynamics, clinical characteristics, therapy, and outcomes. As is well known, HF with preserved ejection fraction more frequently affects females, with diabetes and arterial hypertension representing the most critical determinants of HF. On the other hand, women are traditionally underrepresented in clinical trials and are often considered undertreated. However, it is not clear whether such differences reflect cultural behaviors and clinical inertia or if they indicate different clinical profiles and the impact of sex on hard clinical outcomes. We aimed to review the sex-related differences in patients affected by HF.