Sex-Based Heart Transplant Outcomes After Bridging With Centrifugal Left Ventricular Assist Devices

Gender and Race Differences in HeartMate3 Left Ventricular Assist Device as a Bridge to Transplantation

BACKGROUND

Gender and racial disparities exist after left ventricular assist device (LVAD) implantation. Compared with older devices, the HeartMate 3 (HM3) (Abbott Cardiovascular) has demonstrated improved survival. Whether HM3 differentially improves outcomes by gender or race and ethnic groups is unknown.

OBJECTIVES

The purpose of this study is to examine differences by gender and race in the use of HM3 among patients listed for heart transplantation (HT) and associated waitlist and post-transplant outcomes.

METHODS

The authors examined all patients (20% women, 33% Black) who received LVADs as bridge to transplantation (BTT) between January 2018 and June 2020, in the OPTN (Organ Procurement and Transplantation Network) database. Trends in use of HM3 were evaluated by gender and race. Competing events of death/delisting and transplantation were evaluated using subdistribution hazard models. Post-transplant outcomes were evaluated using multivariate logistic regression adjusted for demographic, clinical, and donor characteristics.

RESULTS

Of 11,524 patients listed for HT during the study period, 955 (8.3%) had HM3 implanted as BTT. Use of HM3 increased for all patients, with no difference in use by gender (P = 0.4) or by race (P = 0.2). Competing risk analysis did not demonstrate differences in transplantation or death/delisting in men compared with women (HT: adjusted HR [aHR]: 0.92 [95% CI: 0.70-1.21]; death/delisting: aHR: 0.91 [95% CI: 0.59-1.42]), although Black patients were transplanted fewer times than White patients (HT: aHR: 0.72 [95% CI: 0.57-0.91], death/delisting: aHR: 1.36 [95% CI: 0.98-1.89]). One-year post-transplant survival was comparable by gender (aHR: 0.52 [95% CI: 0.21-1.70]) and race (aHR: 0.76 [95% CI: 0.34-1.70]), with no differences in rates of stroke, acute rejection, or graft failure.

CONCLUSIONS

Use of HM3 among patients listed for HT has increased over time and by gender and race. Black patients with HM3 were less likely to be transplanted compared with White patients, but there were no differences in post-transplant outcomes between these groups or between men and women.

Durable mechanical circulatory support as bridge to heart transplantation

PURPOSE OF REVIEW

Durable mechanical circulatory support (MCS) technology has changed over time as devices have evolved from pulsatile to continuous flow support. In this review, we discuss recent data and substantial changes to current practice as it pertains to the subject of current era durable left ventricular assist devices (LVADs) as a bridge to heart transplantation.

RECENT FINDINGS

The results of heart transplantation in patients bridged with durable LVAD support are satisfactory even after prolonged duration of support. Reports of recent experience with LVAD related infection suggest that this complication has limited impact on post-transplant outcomes. Important sex-related disparities continue to exist following durable LVAD implantation. Recent changes in the United Network for Organ Sharing donor heart allocation policy have resulted in a drastic decline in the use of durable LVAD support for Bridge to Transplant in the United States.

SUMMARY

Durable MCS in the form of LVAD as a BTT strategy continues to evolve over time. Optimization of its role in the treatment of end-stage heart failure, particularly in females will need to be the focus of future research.

Sex Differences in Heart Failure

Heart failure (HF) continues to be a major contributor of morbidity and mortality for men and women alike, yet how the predisposition for, course and management of HF differ between men and women remains underexplored. Sex differences in traditional risk factors as well as sex-specific risk factors influence the prevalence and manifestation of HF in unique ways. The pathophysiology of HF differs between men and women and may explain sex-specific differences in clinical presentation and diagnosis. This in turn contributes to variation in response to both pharmacologic and device/surgical therapy. This review examines sex-specific differences in HF spanning prevalence, risk factors, pathophysiology, presentation, and therapies with a specific focus on highlighting gaps in knowledge with calls to action for future research efforts.