Hardwiring Heart Transplant Volume Growth

Heart allograft acceptance rates vary among transplant centers and candidates on the waiting list at centers with lower acceptance rates are more likely to experience mortality while on the waiting list.¹ Higher transplant rates may spare patients the need for durable ventricular assist devices and preserve end-organ function, thereby reducing the risk of morbidity and mortality at the time of transplant. Although the advantages of higher transplant rates are myriad, so are the barriers to increasing use, including (1) a culture of conservatism regarding interpretation of risk associated with donors and donor-recipient matching, (2) regulatory provisions favoring constant improvement in posttransplant survival, (3) absence of data from randomized clinical trials, and (4) stagnant registration for donation. Simultaneously, several factors favoring higher heart recovery rates have increased, including (1) an increase in the US population, (2) fatalities related to the opioid epidemic, (3) the use of donors with active hepatitis C, and (4) increasing knowledge of the role of risk factors in heart allocation.² However, more availability of donor hearts has not automatically translated to increased transplant rates for transplant centers. Of these opposing factors, a transplant center’s publicly reported statistics factor prominently into decision-making relative to risk taking while trying to maintain the fiduciary responsibility to the patient. This conundrum underscores the need for transplant programs to carefully plan strategies to mitigate risk while growing their transplant volume. Nonetheless, for programs that are willing to expend resources and embark on concerted systematic improvement, heart transplant volumes can be increased, as reported by Mori et al.³

The Yale New Haven Hospital heart transplant program reported an impressive 5-fold increase in heart transplant volume from August 2018 to August 2019 compared with the previous 4-year period (from August 2014 to August 2018).³ The authors attribute the increase in volume to institutional-level strategic changes, including (1) restructuring of the heart failure service, (2) change in surgical leadership, (3) adoption of a more aggressive philosophy on donor acceptance and recipient selection and (4) the addition of critical program infrastructure (ie, procurement surgeon and transplant coordinator). Growth coincided with the implementation of the updated United Network for Organ Sharing allocation system in 2018. The program’s donor acceptance rates more than tripled (from 6.4% to 20.5%), while wait times decreased from a median of 242 days to 41 days. Increased use of temporary circulatory support devices also played a key role in successfully bridging patients to primary transplant without the use of durable ventricular assist devices. Waiting list mortality and survival rates at 180 days were not significantly different between the 2 eras. Given the success of this intentional effort, what can other programs derive from this experience in their quest to increase transplant volumes to their patients’ and programs’ benefit?

Foremost in their strategy was a cultural change toward donor age and hypertension—factors that result in donor nonuse in many programs. In general, concerted reading of the literature on heart transplant risk factors reveals that many purported risk factors increase the risk of graft failure only minimally across the range of encountered donors. For many recipients, the risk of waiting far exceeds the risks of the mild or moderate increase in risk associated with 1 donor risk factor. Thus, accepting donors with a greater proportion of higher-risk features can have salutary outcomes. Mori et al³ reported an increase of 10 years in their mean donor age in the 2 comparative time periods without compromising recipient outcomes. This finding suggests that previously held concepts about what constitutes a “usable donor” were perhaps inaccurate or inflated based on a binary treatment of risk factors as good or bad, creating a false dichotomy.

Breaking out of traditional, more conservative practice patterns associated with donor and recipient selection is not easy when transplant centers are heavily regulated and measured by publicly reported outcomes. Paradoxically, adverse events among lower-risk donor-recipient pairs may have more influence in generating a poor performance rating than higher-risk pairs based on the accounting of risk as calculated by the Scientific Registry of Transplant Recipients. Whether Mori et al³ performed detailed reviews of their publicly reported statistics is unknown, but programs are engaging in this activity and many will discover that a higher-volume program that accommodates risk is best for the recipients and public reporting statistics. The results of the Collaborative Innovation and Improvement Network in renal transplantation suggest that marginal gains in donor recovery may be possible with novel quality assessment methods.⁴

Early adopters of higher-risk donors may appreciate marginal gains in transplant volume until other centers follow. The heart transplant community, as a whole, has taken a relatively cautious approach toward adopting the use of hepatitis C viremic nucleic acid test–positive donors. However, progressive heart transplant programs have seen reduced waiting times and increased transplant rates after adopting the use of hepatitis C–positive donor organs.⁵ Ex vivo perfusion systems allow the use of remote donors in inaccessible areas, especially if those areas are remote to all other centers. Donation after cardiac death also offers some promise to increase the donor pool, but at the risk of additional travel time for procurement teams and almost certainly with more cost to programs. However, without a marked increase in donors and with other programs eager to grow, the use of nontraditional donors and technology are unlikely to create a tide of new transplants. The use of donors with heretofore unfavorable risk factors is much more likely to increase donation.

We believe that further opportunities exist to improve donor use; however, all opportunities come with some degree of clinical and financial risk. For early adopters, an increase in transplant rates can be expected and maintained with ongoing quality monitoring and measured discourse in the case of adverse events. Quality improvement efforts, as reported by Mori et al,³ have the greatest potential to permanently switch the norms in donor and donor-recipient matching away from inappropriate conservatism and toward increased heart transplant rates.

Published: September 18, 2020. doi:10.1001/jamanetworkopen.2020.17595

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2020 Bjelkengren J et al. JAMA Network Open.

Corresponding Author: Todd F. Dardas, MD, MS, Division of Cardiology, Department of Medicine, University of Washington, 1959 NE Pacific St, Box 356422, A 506 E, Seattle, WA 98195 (tdardas@uw.edu).

Conflict of Interest Disclosures: Dr Dardas reported managing quality improvement for the University of Washington Division of Cardiology, which includes the transplant program. No other disclosures were reported.