First-year clinical outcomes in gender-mismatched heart transplant recipients

Recipient donor sex combinations in solid organ transplantation and impact on clinical outcome: A scoping review

INTRODUCTION

Solid organ transplantation (SOT) is a lifesaving treatment for end-stage organ failure. Although many factors affect the success of organ transplantation, recipient and donor sex are important biological factors influencing transplant outcome. However, the impact of the four possible recipient and donor sex combinations (RDSC) on transplant outcome remains largely unclear.

METHODS

A scoping review was carried out focusing on studies examining the association between RDSC and outcomes (mortality, graft rejection, and infection) after heart, lung, liver, and kidney transplantation. All studies up to February 2023 were included.

RESULTS

Multiple studies published between 1998 and 2022 show that RDSC is an important factor affecting the outcome after organ transplantation. Male recipients of SOT have a higher risk of mortality and graft failure than female recipients. Differences regarding the causes of death are observed. Female recipients on the other hand are more susceptible to infections after SOT.

CONCLUSION

Differences in underlying illnesses as well as age, immunosuppressive therapy and underlying biological mechanisms among male and female SOT recipients affect the post-transplant outcome. However, the precise mechanisms influencing the interaction between RDSC and post-transplant outcome remain largely unclear. A better understanding of how to identify and modulate these factors may improve outcome, which is particularly important in light of the worldwide organ shortage. An analysis for differences of etiology and causes of graft loss or mortality, respectively, is warranted across the RDSC groups.

PRACTITIONER POINTS

Recipient and donor sex combinations affect outcome after solid organ transplantation. While female recipients are more susceptible to infections after solid organ transplantation, they have higher overall survival following SOT, with causes of death differing from male recipients. Sex-differences should be taken into account in the post-transplant management.

Choosing wisely: incorporating appropriate donor-recipient size matching in heart transplantation

Historically, transplantation of a female donor heart to male recipient has been viewed with caution given evidence of suboptimal outcomes, particularly in special populations such as patients with pulmonary hypertension or those supported by ventricular assist devices. However, the use of predicted heart mass ratio for donor-recipient size matching demonstrated that the size of the organ rather than sex of the donor was most responsible for the outcomes. With the advent of the predicted heart mass ratio, avoiding female donor hearts for male recipients is no longer justified and may result in unnecessary waste of available organs. In this review, we highlight the value of donor-recipient sizing by predicted heart mass ratio and summarize the evidence of different approaches to the donor-to-recipient size and sex matching. We conclude that the utilization of predicted heart mass is currently considered a preferred method of matching heart donors and recipients.

Influence of Sex-Mismatch on Prognosis After Heart Transplantation

The influence of donor and recipient sex on prognosis after heart transplantation has been analyzed in single, multi-center studies, and international registries. In most of them, sex-mismatch was identified as a risk factor for the worst prognosis, especially in men recipients of female heart. This could be attributed to physiological differences between women and men, differences in complications rates after heart transplantation (rejection, cardiovascular allograft vasculopathy, and primary graft failure), and pulmonary hypertension of the recipient. Confounding variables as age, urgent transplantation, and size-mismatch should also be considered. When allocating a graft, sex-mismatch should be considered but its influence in long-term survival should be further explored.

Sex-mismatch influence on survival after heart transplantation: A systematic review and meta-analysis of observational studies

INTRODUCTION AND OBJECTIVES

Heart transplantation (HT) is the treatment for patients with end-stage heart disease. Despite contradictory reports, survival seems to be worse when donor/recipient sex is mismatched. This systematic review and meta-analysis aims to synthesize the evidence on the effect of donor/recipient sex mismatch after HT.

METHODS

We searched PubMed and EMBASE until November 2017. Comparative cohort and registry studies were included. Published articles were systematically selected and, when possible, pooled in a meta-analysis. The primary endpoint was one-year mortality.

RESULTS

After retrieving 556 articles, ten studies (76 175 patients) were included in the quantitative meta-analysis. Significant differences were found in one-year survival between sex-matched and mismatched recipients (odds ratio (OR) 1.30, 95% confidence interval (CI) 1.25-1.35, P < .001). In female recipients, we found that sex mismatch was not a risk factor for one-year mortality (OR = 0.93, 95% CI = 0.85-1.00, P = .06). However, in male recipients, we found that it was a risk factor for one-year mortality (OR = 1.38, 95% CI = 1.31-1.44, P < .001).

CONCLUSIONS

Sex mismatch increases one-year mortality after HT in male recipients. Its influence in long-term survival should be further explored with high-quality studies.

ISHLT Primary Graft Dysfunction Incidence, Risk Factors, and Outcome: A UK National Study

BACKGROUND

Heart transplantation (HTx) remains the most effective long-term treatment for advanced heart failure. Primary graft dysfunction (PGD) continues to be a potentially life-threatening early complication. In 2014, a consensus statement released by International Society for Heart and Lung Transplantation (ISHLT) established diagnostic criteria for PGD. We studied the incidence of PGD across the United Kingdom.

METHODS

We analyzed the medical records of all adult patients who underwent HTx between October 2012 and October 2015 in the 6 UK heart transplant centers Preoperative donor and recipient characteristics, intraoperative details, and posttransplant complications were compared between the PGD and non-PGD groups using the ISHLT definition. Multivariable analysis was performed using logistic regression.

RESULTS

The incidence of ISHLT PGD was 36%. Thirty-day all-cause mortality in those with and without PGD was 31 (19%) versus 13 (4.5%) (P = 0.0001). Donor, recipient, and operative factors associated with PGD were recipient diabetes mellitus (P = 0.031), recipient preoperative bilateral ventricular assist device (P < 0.001), and preoperative extracorporeal membranous oxygenation (P = 0.023), female donor to male recipient sex mismatch (P = 0.007), older donor age (P = 0.010), and intracerebral haemorrhage/thrombosis in donor (P = 0.023). Intraoperatively, implant time (P = 0.017) and bypass time (P < 0.001) were significantly longer in the PGD cohort. Perioperatively, patients with PGD received more blood products (P < 0.001). Risk factors identified by multivariable logistic regression were donor age (P = 0.014), implant time (P = 0.038), female: male mismatch (P = 0.033), recipient diabetes (P = 0.051) and preoperative ventricular assist device/extracorporeal membranous oxygenation support (P = 0.012).

CONCLUSIONS

This is the first national study to examine the incidence and significance of PGD after HTx using the ISHLT definition. PGD remains a frequent early complication of HTx and is associated with increased mortality.

High Survival and Mortality Characteristics in Heart Transplant Patients at a National Institute

OBJECTIVES

The identification of variables related to the survival of heart transplant patients is vital for a good medical practice. Few studies have examined this issue in a Latin American population. Therefore, the aim of this study was to analyze, retrospectively, the survival and mortality characteristics of patients after heart transplant.

MATERIALS AND METHODS

Information on patients was obtained through review of medical records; we collected information on all patients who underwent this procedure from 2010 to 2015. Sociodemographic, clinical, and surgical characteristics associated with posttransplant mortality were analyzed. Survival over 5 years was determined with the Kaplan-Meier method.

RESULTS

The overall survival rate of the 35 patients who underwent heart transplant was 85%. Those with low total cholesterol values (< 160 mg/dL) had a lower survival at 5 years than patients with higher values (74% vs 100%; P = .044). The overall mortality was 14.3%, and the main cause of death was acutegraft rejection (40%). Lower total cholesterol level (< 160 mg/dL; P = .036), presence of chronic kidney disease stage 1 (P = .049), intraoperative bleeding (> 600 mL; P = .013), and number of sepsis incidents (P = .03) were more frequent in patients who died.

CONCLUSIONS

The survival in our institute at 5 years is higher than shown in the reported literature, and the mortality is lower. In addition, a low total cholesterol value negatively affects survival of heart transplant patients at 5 years.

Mortality, rehospitalization, and post-transplant complications in gender-mismatched heart transplant recipients

BACKGROUND

Limited research has been published on outcomes in heart transplant (HT) recipients with gender-mismatched donors.

OBJECTIVE

Compare 3-year post-transplant outcomes in 2 groups of gender-mismatched HT recipients and a no-mismatch group.

METHODS

Sample: 347 HT recipients: 21.3% (74) received a heart from the opposite gender: Group 1: same gender donor/recipient (273, 78.7%); Group 2: female donor/male recipient (40, 11.5%); Group 3: male donor/female recipient (34, 9.8%).

OUTCOMES

mortality, hospitalization, and complications.

RESULTS

Female patients with male heart donors had shorter 3-year survival, were rehospitalized more days after HT discharge, and had more treated acute rejection episodes and cardiac allograft vasculopathy. No differences were found in: HT length of stay, respiratory failure, stroke, cancer, renal dysfunction, steroid-induced diabetes, number of IV-treated infections, or the timing of infection and rejection.

CONCLUSION

Female HT recipients with male donors had worse 3-year outcomes as compared to male-mismatch and no-mismatch groups.

Clinical outcomes in overweight heart transplant recipients

BACKGROUND

Few studies have examined the impact of patient weight on heart transplant (HT) outcomes.

OBJECTIVES

Nine outcomes were compared in 2 groups of HT recipients (N = 347) based on their mean body mass index (BMI) during the first 3 years post-HT.

METHODS

Group 1 consisted of 108 non-overweight patients (BMI <25; mean age 52; 29.6% females; 16.7% minorities). Group 2 consisted of 239 overweight patients (BMI ≥25; mean age 52; 15.9% females; 13.8% minorities). Outcomes were: survival, re-hospitalization, rejections, infections, cardiac allograft vasculopathy (CAV), stroke, renal dysfunction, diabetes, and lymphoma.

RESULTS

Non-overweight patients had shorter survival, were re-hospitalized more days after the HT discharge, and had more lymphoma and severe renal dysfunction. Overweight patients had more CAV, steroid-induced diabetes, and acute rejections.

CONCLUSIONS

Overweight HT patients had better survival, but more rejections, CAV, and diabetes. Non-overweight HT patients had worse survival, plus more re-hospitalization time, lymphoma, and renal dysfunction.

Late rejection occurred in recipients who experienced acute cellular rejection within the first year after heart transplantation

Serial endomyocardial biopsies (EMBs) are scheduled even several years after heart transplantation (HTx) to monitor for late rejection (LR). However, repeated EMBs are associated with an increased risk for fatal complications and decrease the quality of life of the recipient. We retrospectively analyzed clinical data from 42 adult recipients who had received HTx and were followed > 1 year at the University of Tokyo Hospital. Five recipients experienced LR at 1130 ± 157 days after HTx, and all 5 had experienced acute cellular rejection (ACR) with ISHLT grade ≥ 2R within the first year, which was treated with methylprednisolone pulse therapy (sensitivity, 1.000; specificity, 0.7027). Logistic regression analyses demonstrated that positive panel reactive antibody (PRA) was the only significant predictor for LR among all parameters at 1 year after HTx (P = 0.020, odds ratio 24.00). Among the 5 recipients with LR, LR occurred earlier in the two PRA positive recipients than in those with a negative PRA (981 ± 12 versus 1230 ± 110 days, P = 0.042). Among the perioperative parameters, gender mismatch [n = 13 (31%)] was the only significant predictor for ACR within the first year in logistic regression analyses (P = 0.042, odds ratio 4.200). In conclusion, the current schedule of serial EMBs should perhaps be reconsidered for recipients without any history of ACR within the first year due to their lower risk of LR.

Donor/recipient sex mismatch and survival after heart transplantation: only an issue in male recipients? An analysis of the Spanish Heart Transplantation Registry

The results of studies on the association between sex mismatch and survival after heart transplantation are conflicting. Data from the Spanish Heart Transplantation Registry. From 4625 recipients, 3707 (80%) were men. The donor was female in 943 male recipients (25%) and male in 481 female recipients (52%). Recipients of male hearts had a higher body mass index (25.9 ± 4.1 vs. 24.3 ± 3.7; P < 0.01), and male donors were younger than female donors (33.4 ± 12.7 vs. 38.2 ± 12.3; P < 0.01). No further relevant differences related to donor sex were detected. In the univariate analysis, mismatch was associated with mortality in men (hazard ratio [HR], 1.18; 95% confidence interval [CI], 1.06-1.32; P = 0.003) but not in women (HR, 0.91; 95% CI 0.74-1.12; P = 0.4). A significant interaction was detected between sex mismatch and recipient gender (P = 0.02). In the multivariate analysis, sex mismatch was associated with long-term mortality (HR, 1.14; 95% CI 1.01-1.29; P = 0.04), and there was a tendency toward significance for the interaction between sex mismatch and recipient gender (P = 0.08). In male recipients, mismatch increased mortality mainly during the first month and in patients with pulmonary gradient >13 mmHg. Sex mismatch seems to be associated with mortality after heart transplantation in men but not in women.