Temporary Mechanical Circulatory Support Use and Clinical Outcomes of Simultaneous Heart/Kidney Transplant Recipients in the Pre- and Post-heart Allocation Policy Change Eras

Bridge to simultaneous heart-kidney transplantation via extracorporeal life support: National outcomes in the new heart allocation policy era

BACKGROUND

Since United Network for Organ Sharing (UNOS) revised their heart allocation policy in 2018, usage of veno-arterial extracorporeal life support (VA-ECLS) has dramatically increased as a bridge to transplant. This study investigated outcomes of VA-ECLS patients bridged to simultaneous heart-kidney transplant (SHK) in the new policy era.

METHODS

This study included 774 adult patients from the UNOS database who received SHK between 10/18/18 and 12/31/21 and compared patients bridged to transplant on VA-ECLS (n = 50) with those not bridged (n = 724).

RESULTS

At baseline, SHK recipients bridged from VA-ECLS were younger (50.5 vs 58.0 years, p = 0.007), had higher estimated glomerular filtration rate (eGFR) at time of transplant (47.6 vs 30.1, p < 0.001), and spent fewer days on the waitlist (7.0 vs 33.5 days, p < 0.001). In the perioperative period, VA-ECLS was associated with higher rates of temporary dialysis (56.0% vs 28.0%, p < 0.001) but similar 2-year cumulative incidence of chronic dialysis (7.5% vs 5.4%, p = 0.800) and renal allograft failure (12.0% vs 8.1%, p = 0.500) compared to non-ECLS cohort. However, VA-ECLS patients had decreased survival to discharge (76.0% vs 92.7%, p < 0.001) and 2-year post-transplant survival (71.7% vs 83.0%, p = 0.004), as well as greater 2-year cumulative incidence of cardiac allograft failure (10.0% vs 2.7%, p = 0.002). Multivariable analyses found VA-ECLS at time of transplant to be independently associated with 2-year post-transplant mortality (HR [95% CI]: 3.40 [1.66-6.96], p = 0.001) and cardiac allograft failure (sub-distribution hazard ratio [SHR] [95% CI]: 8.51 [2.77-26.09], p < 0.001).

CONCLUSION

Under the new allocation policy, patients bridged to SHK from VA-ECLS displayed greater early mortality and cardiac allograft failure but similar renal outcomes compared to non-ECLS counterparts.

Evolutions in Combined Heart-Kidney Transplant

PURPOSE OF REVIEW

This review describes management practices, outcomes, and allocation policies in candidates for simultaneous heart-kidney transplantation (SHKT).

RECENT FINDINGS

In patients with heart failure and concomitant kidney disease, SHKT confers a survival advantage over heart transplantation (HT) alone in patients with dialysis dependence or an estimated glomerular filtration rate (eGFR) < 40 mL/min/1.73 m2. However, when compared to kidney transplantation (KT) alone, SHKT is associated with worse patient and kidney allograft survival. In September 2023, the United Network of Organ Sharing adopted a new organ allocation policy, with strict eligibility criteria for SHKT and a safety net for patients requiring KT after HT alone. While the impact of the policy change on SHKT outcomes remains to be seen, strategies to prevent and slow development of kidney disease in patients with heart failure and to prevent kidney dysfunction after HT and SHKT are necessary.

Multimodality Imaging in Advanced Heart Failure for Diagnosis, Management and Follow-Up: A Comprehensive Review

Advanced heart failure (AHF) presents a complex landscape with challenges spanning diagnosis, management, and patient outcomes. In response, the integration of multimodality imaging techniques has emerged as a pivotal approach. This comprehensive review delves into the profound significance of these imaging strategies within AHF scenarios. Multimodality imaging, encompassing echocardiography, cardiac magnetic resonance imaging (CMR), nuclear imaging and cardiac computed tomography (CCT), stands as a cornerstone in the care of patients with both short- and long-term mechanical support devices. These techniques facilitate precise device selection, placement, and vigilant monitoring, ensuring patient safety and optimal device functionality. In the context of orthotopic cardiac transplant (OTC), the role of multimodality imaging remains indispensable. Echocardiography offers invaluable insights into allograft function and potential complications. Advanced methods, like speckle tracking echocardiography (STE), empower the detection of acute cell rejection. Nuclear imaging, CMR and CCT further enhance diagnostic precision, especially concerning allograft rejection and cardiac allograft vasculopathy. This comprehensive imaging approach goes beyond diagnosis, shaping treatment strategies and risk assessment. By harmonizing diverse imaging modalities, clinicians gain a panoramic understanding of each patient's unique condition, facilitating well-informed decisions. The aim is to highlight the novelty and unique aspects of recently published papers in the field. Thus, this review underscores the irreplaceable role of multimodality imaging in elevating patient outcomes, refining treatment precision, and propelling advancements in the evolving landscape of advanced heart failure management.

Decreased survival of simultaneous heart-kidney transplant recipients in the new heart allocation era

BACKGROUND

In 2018, the United Network for Organ Sharing (UNOS) modified their heart allocation policy to reduce waitlist mortality. The rates of simultaneous heart-kidney transplant (SHKT) have dramatically increased in recent years, despite increased rates of posttransplant renal failure in the new policy era. This study sought to investigate the impact of the new allocation system on waitlist and posttransplant outcomes of simultaneous heart-kidney transplantation.

METHODS

Adult patients listed for SHKT between 2012 and 2021 were included. Patients were cross-validated across both Thoracic and Kidney UNOS databases to confirm accurate listing and transplant data. Patients were stratified according to listing era. The Fine and Gray model was used to assess waitlist outcomes and posttransplant renal graft function. Kaplan-Meier analysis and Cox regression were used to compare posttransplant survival.

RESULTS

A total of 2,588 patients were included, of whom 1,406 (54.1%) were listed between 2012 and 2018 (era 1) and 1,182 (45.9%) between 2019 and 2021 (era 2). Era 2 was associated with increased likelihood of transplant (adjusted Sub-hazard ratios (aSHR): 1.52; p < 0.01) and decreased waitlist mortality (aSHR: 0.63; p < 0.01). Posttransplant survival at 2 years was decreased in era 2 (78.8% vs 86.9%; p < 0.01). Undersized hearts (hazard ratio [HR]: 2.02; p < 0.01), use of extracorporeal membrane oxygenation (HR: 2.67; p < 0.1), and transplants performed following the policy change (HR: 1.45; p = 0.03) were associated with increased mortality. Actuarial survival (combined waitlist and posttransplant) was significantly lower in the modern era (71.6% vs 62.2%; p = 0.02).

CONCLUSIONS

The allocation policy change has improved waitlist outcomes in patients listed for SHKT but potentially at the cost of worsened posttransplant outcomes.