OPTN/SRTR 2022 Annual Data Report: Heart

OPTN/SRTR 2022 Annual Data Report: Heart

Monica M. Colvin1,2, Jodi M. Smith1,3, Yoon Son Ahn1, Dzhuliyana K. Handarova4, Alina C. Martinez4, Kelsi A. Lindblad4, Ajay K. Israni1,5,6, Jon J. Snyder1,5,6

1Scientific Registry of Transplant Recipients, Hennepin Healthcare Research Institute, Minneapolis, MN

2Department of Cardiology, University of Michigan, Ann Arbor, MI

3Department of Pediatrics, University of Washington, Seattle, WA

4Organ Procurement and Transplantation Network, United Network for Organ Sharing, Richmond, VA

5Department of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN

6Department of Medicine, Hennepin Healthcare, University of Minnesota, Minneapolis, MN

Abstract

The number of heart transplants in the United States has continued to increase. Since 2011, pediatric heart transplants have increased 31.7% to 494 and adult heart transplants have increased 85.8% to 3,668 in 2022. The numbers of new candidates for pediatric and adult heart transplants have also increased, with 703 new pediatric candidates and 4,446 new adult candidates in 2022. Adult heart transplant rates continue to rise, peaking at 122.5 transplants per 100 patient-years in 2022; however, the pediatric heart transplant rate decreased to its lowest rate in the past decade, 104.2 transplants per 100 patient-years, a decrease of 13.9% from 121 transplants per 100 patient-years in 2011. Despite this, pretransplant mortality among pediatric candidates has decreased by 52.2%, from 20.8 deaths per 100 patient-years in 2011 to 10.0 deaths per 100 patient-years in 2022, but remains excessive for candidates younger than 1 year at 25.7 deaths per 100 patient-years. Among adult candidates, pretransplant mortality declined from 15 deaths per 100 patient-years in 2011 to 8.7 deaths per 100 patient-years in 2022. Since 2011, posttransplant mortality has been stable to slightly better; among recipients who underwent transplant in 2015-2017, the 1-, 3-, and 5-year pediatric survival rates were 93.7%, 89.2%, and 85.0%, respectively, and the adult survival rates were 91.3%, 85.7%, and 80.4%. Donor trends have been favorable, with an increase in the numbers of hearts recovered and growing numbers of hearts procured after circulatory death.

Keywords: Allocation, donor, heart failure, heart transplant, left ventricular assist device, mechanical circulatory support, outcomes

1 Introduction

Heart allocation policy, particularly the adult heart allocation policy, has evolved and has universally changed practice.1,2 Although the 2018 policy may have contributed to better access and faster transplant rates,3 particularly in high-urgency candidates, and lower overall pretransplant mortality rates, the policy changes inadvertently promoted short-term circulatory support devices as a means to transplant4,5 and resulted in excessive requests for exceptions.6 Despite increased transplant rates among candidates listed at statuses 1 and 2, pretransplant mortality, which was previously declining, increased between 2021 and 2022, a concerning signal. Nevertheless, the promise of continuous distribution and a points-based allocation policy may help to mitigate some of the unintended consequences of the policy by removing hard boundaries for listing and for moving to a higher status, and by providing weights to clinically relevant attributes. The Annual Data Report provides an evaluation of trends in adult and pediatric heart transplant waiting lists, donation, transplants, and outcomes in the United States. This year, the race and ethnicity category has been expanded to include Multiracial and Native American, and limited data are available for hearts recovered after circulatory death. Inherent differences in calculations during 2018 should be considered when assessing status-specific rates obtained during 2018 among adult candidates and recipients. As a result, trends in adult heart transplant that are stratified by status are compared to 2019 as opposed to 2018 where appropriate.

2 Adult Heart Transplant

2.2 Adult Heart Transplant Rates

Transplant rates have been increasing since 2015, and in 2022, the overall transplant rate was 122.5 transplants per 100 patient-years; this is an increase of 81.8% since 2011, when the rate was 67.4 transplants per 100 patient-years (Figure HR 13). Similar increases were seen in all age groups, with the greatest increase occurring in candidates aged 18-34 years. Candidates aged 65 years or older received transplants most rapidly at 138.8 transplants per 100 patient-years in 2022 (Figure HR 14). Regarding race and ethnicity, candidates in the Asian category underwent transplant at the highest rate, at 175.6 transplants per 100 patient-years, followed by those in the Hispanic, White, Black, and Other categories. In all categories, there was an increase in transplant rate since 2011, with the greatest change, 173.4%, occurring in the category classified as Other (Figure HR 15). By diagnosis, candidates with valvular heart disease had the highest transplant rate (145.6 transplants per 100 patient-years), followed by cardiomyopathy, Other/unknown, coronary artery disease, and congenital heart disease (128.7, 122.9, 113.5, and 98.0 transplants per 100 patient-years, respectively) (Figure HR 16). The transplant rate for all blood types continues to increase, with the greatest increase since 2011 (110%) occurring in blood type A. The transplant rate for blood type AB increased 89% since 2018 and remains the highest rate of all blood types, at 376.6 transplants per 100 patient-years in 2022, more than twice that of blood type A, which has the second highest transplant rate (Figure HR 17). The transplant rate among women exceeds that of men: 143.1 versus 116.4 transplants per 100 patient-years (Figure HR 18). Since 2019, transplant rates have declined slightly for statuses 1 and 2 and increased for the other active statuses (Figure HR 20). Status 1 candidates continue to have the highest rate of transplant: 1,640 transplants per 100 patient-years in 2022. Most patients who were newly listed in 2019 underwent transplant within the first year of listing (63.8%); by 3 years, 71.8% had undergone transplant, 6.5% were still waiting, 4.0% had died, and 17.7% were removed for other reasons (Figure HR 23).

2.3 Adult Pretransplant Mortality

Overall pretransplant mortality declined from 15 deaths per 100 patient-years in 2011 to 8.7 deaths per 100 patient-years in 2019 and has remained at a plateau in 2022 (Figure HR 25). Since 2011, pretransplant mortality has declined for all age groups but remains highest for persons aged 65 years or older, at 14.4 deaths per 100 patient-years in 2022 (Figure HR 26). Pretransplant mortality declined for all race and ethnicity categories since 2011 except for Asian. Candidates in the Asian category had slightly higher pretransplant mortality in 2022, at 9.7 deaths per 100 patient-years, compared with 8.5 deaths per 100 patient-years in 2012, while pretransplant mortality decreased substantially in other race and ethnicity categories (Figure HR 27). Candidates with congenital heart disease had the greatest improvement in pretransplant mortality rate, with a decline of 51.3% since 2011 to 6.2 deaths per 100 patient-years in 2022, the lowest of all the diagnoses. Pretransplant mortality increased 50.1% in the valvular heart disease group, from 8.77 deaths per 100 patient-years in 2011 to 13.2 deaths per 100 patient-years in 2022. This was second to candidates classified with an “Other/unknown” diagnosis, who had the highest pretransplant mortality in 2022: 15.7 deaths per 100 patient-years (Figure HR 29).

Following the 2018 heart allocation policy, there was an increase in the prevalence of short-term circulatory support devices prior to transplant.4 In 2022, the proportion of patients on any life support declined to 74.4% compared with 82.3% in 2019. There was an increase in use of all circulatory support devices, except for total artificial heart, which declined to only eight cases in 2022 (Table HR 7). The OPTN policy to collect data on Impella 5.5 became effective on August 16, 2023; therefore, this device is not included in this analysis.

Since 2019, pretransplant mortality increased among candidates listed at statuses 1, 2, and 3 and improved in those listed as statuses 4, 5, and 6 (Figure HR 32). Pretransplant mortality among status 1 candidates had declined to 81.2 deaths per 100 patient-years in 2021, but increased again to 143 deaths per 100 patient-years in 2022, which far exceeds that of candidates listed as status 2 (46.0 deaths per 100 patient-years). Candidates listed as status 6 had the lowest pretransplant mortality rate in 2022 (3.6 deaths per 100 patient-years), followed by status 4 (4.8 deaths per 100 patient-years). Candidates listed as status 5 continue to have a higher pretransplant mortality rate (10.4 deaths per 100 patient-years) than candidates listed at status 4 (Figure HR 32). While there remains concern in the community regarding the slower rate of transplant for candidates listed as status 4, namely those with a left ventricular assist device, the rate of transplant does not appear to affect mortality among candidates listed as status 4. Candidates listed as status 4 had the second lowest pretransplant mortality, while pretransplant mortality continues to be highest among the statuses associated with hemodynamic instability or multiorgan failure (statuses 1, 2, 3, and 5) (Figure HR 32). Pretransplant mortality rates in 2022 varied widely by donation service area: from 0 to 44.92 deaths per 100 patient-years, with a mean of 9.6 deaths per 100 patient-years (Figure HR 33).

Deaths within 6 months of removal from the transplant list for reasons other than transplant or death have declined since 2011, although these percentages slightly increased from 11.5% in 2021 to 14.8% in 2022 (Figure HR 34). Death within 6 months of removal was highest in 2022 among candidates aged 65 years or older (23.7%) and lowest among candidates aged 18-34 years (7.0%) (Figure HR 35). In 2022, Asian candidates had the highest percentage of death within 6 months of removal; there was a 62% increase from 2011 (14.3%) to 2022 (23.1%). Death within 6 months of removal also increased for candidates in the Hispanic category and declined for those in the Black, White, and Other categories (Figure HR 36). Death within 6 months of removal from the list also increased among candidates listed as status 1, from 15% in 2019 to 44.4% in 2022, while decreasing in all other statuses. Death within 6 months of removal was second highest in temporarily inactive candidates (16.5%), followed by candidates listed as status 5 (11.1%) (Figure HR 38).

2.6 Adult Posttransplant Survival and Morbidity

Posttransplant mortality has been stable to slightly better since 2011, except for 10-year mortality, which increased slightly from 35.7% in 2011 to 37.4% in 2012. In 2022, 6-month and 1-year mortality were 7.3% and 9.2%, respectively. Three-year mortality was 15.3% and 5-year mortality was 19.9% (Figure HR 64). Early reductions in survival were seen in age groups older than 34 years, most notably in the 65 years or older group; by 6 months, survival among recipients who received a heart in 2015-2017 was 90.7% in recipients 65 years or older compared with 95.1% in those aged 18-34 years. This trend continued until year 2, after which there was a more pronounced decline in survival for recipients aged 18-34 years relative to the other age groups. By year 5, survival was slightly lower in recipients aged 18-34 years (78.9%) and 65 years or older (77.8%) compared with the other age groups (35-49 and 50-64 years, 82.1% and 81.0%, respectively) (Figure HR 66).

Early survival among recipients who received a heart in 2015-2017 declined more rapidly in the Native American category compared with other race and ethnicity groups, and by 3 months, was 88.0% compared with 92.0%-96.6% in the other categories; this may be affected by the low numbers of Native American transplant recipients. One-year mortality ranged from 88.0% to 92.3% among the race and ethnicity groups. Hispanic recipients also had early declines in mortality. By year 5, survival was highest in recipients categorized as White (81.9%), followed by Asian, Multiracial, Black, Hispanic, and Native American, ranging from 76.0% to 80.4% (Figure HR 67).

Short-term and long-term survival among recipients who received a heart in 2015-2017 were lowest in those with congenital heart disease, reaching 89.7% at 3 months and 75.0% at 5 years. Short-term survival was best among patients with cardiomyopathy, 92.4% at 1 year, but by 5 years, survival in recipients with cardiomyopathy had been surpassed by those with an Other/unknown diagnosis, 82.2% versus 86.6%, respectively (Figure HR 68). Five-year survival in recipients who received a heart in 2015-2017 was slightly worse among patients with a ventricular assist device compared to those without one, at 78.7% versus 82.1%, respectively (Figure HR 70). For the recipients who received a heart in 2019-2020, posttransplant survival was worse at all time points for recipients who underwent transplant at status 5; their survival was only 88.0% at 3 months, compared with 91.7%-95.8% for the other status categories. By 5 years, survival in recipients who underwent transplant at status 5 was only 77.3%, compared with 84.6%-88.7% in the other status groups (Figure HR 72).

Dual organ transplants have increased in heart recipients, and the 5-year survival rate for heart-liver and heart-kidney transplants in 2015-2017 (Figure HR 74) appears comparable to overall heart transplant survival from Figure HR 65. On the other hand, heart-lung continues to have lower survival compared with other heart transplant combinations. Five-year survival for heart-lung transplant is 64.8% and for Other multiorgan transplant is 75% (small numbers), compared with 80.6% for heart-kidney and 82.2% for heart-liver (Figure HR 74). Status 5, the category reserved for multiorgan transplant, tends to have the lowest posttransplant survival of all statuses, which may be driven by heart-lung transplant and Other multiorgan transplant. The decrement in survival for heart-lung transplant occurs during the first month of transplant. By 3 months, 25.0% of Other multiorgan recipients had died, and by 6 months, 14.8% of heart-lung recipients had died. Since 2011, the incidence of acute rejection by 1-year posttransplant has declined for all age groups except recipients aged 65 years or older. The most notable decline, 37% in 2011 to 29% in 2021, occurred in recipients aged 18-34 years, the group with the highest incidence of rejection. Acute rejection was lowest for recipients aged 65 years or older, at 17.9% in 2021, a slight increase from 17.3% in 2011 (Figure HR 75).

3 Pediatric Heart Transplant

3.3 Pediatric Posttransplant Survival and Morbidity

Among pediatric heart transplant recipients in 2021, the rate of acute rejection in the first year was 19.6% in recipients aged 12-17 years, 12.5% in those aged 6-11 years, 10.8% in those younger than 1 year, and 10.3% in those aged 1-5 years (Figure HR 104).

Recipient death occurred in 6.1% of patients at 6-months posttransplant and in 8.0% at 1-year posttransplant among pediatric heart transplants performed in 2021, in 11.8% at 3 years for transplants performed in 2019, in 15.7% at 5 years for transplants performed in 2017, and in 22.0% at 10 years for transplants performed in 2012 (Figure HR 106). Overall, 1-, 3-, and 5-year patient survival rates were 93.7%, 89.2%, and 85.0%, respectively, among recipients who underwent transplant in 2015-2017 (Figure HR 107). By age, 5-year patient survival was 83.2% for recipients younger than 1 year, 84.9% for those aged 1-5 years, 87.1% for those aged 6-11 years, and 85.7% for those aged 12-17 years among recipients who underwent transplant in 2015-2017 (Figure HR 108). By etiology of disease, 5-year patient survival was lowest among children with congenital defects at 81.0% and highest for children with idiopathic-related cardiomyopathy at 93.4% (Figure HR 110). By urgency status, the 5-year patient survival was 84.5% for status 1A pediatric recipients, 90.0% for status 1B recipients, and 77.5% for status 2 recipients (Figure HR 111).

Among pediatric heart transplant recipients in 2011-2017, the overall incidence of posttransplant lymphoproliferative disorder was 5.1% at 5 years; the incidence was 6.6% among recipients who were Epstein Barr virus negative and 3.5% among recipients who were Epstein-Barr virus positive (Figure HR 105).

References

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2.
Shore S, Golbus JR, Aaronson KD, Nallamothu BK. Changes in the United States adult heart allocation policy: Challenges and opportunities. Circ Cardiovasc Qual Outcomes. 2020;13:e005795. doi:10.1161/CIRCOUTCOMES.119.005795
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Golbus JR, Li J, Cascino TM, Tang W, Zhu J, Colvin M, Walsh MN, Nallamothu BK. Greater geographic sharing and heart transplantation waitlist outcomes following the 2018 heart allocation policy. J Heart Lung Transplant. 2023;42:936-942. doi:10.1016/j.healun.2023.02.003
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Cascino TM, Stehlik J, Cherikh WS, Cheng Y, Watt TMF, Brescia AA, Thompson MP, McCullough JS, Zhang M, Shore S, Golbus JR, Pagani FD, Likosky DS, Aaronson KD. A challenge to equity in transplantation: Increased center-level variation in short-term mechanical circulatory support use in the context of the updated U.S. heart transplant allocation policy. J Heart Lung Transplant. 2022;41:95-103. doi:10.1016/j.healun.2021.09.004
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List of Figures

List of Tables




**New adult candidates added to the heart transplant waiting list.** A new adult candidate is one who first joined the list during the given year, without having been listed in a previous year. Previously listed candidates who underwent transplant and subsequently relisted are considered new. Active and inactive patients are included.

Figure HR 1: New adult candidates added to the heart transplant waiting list. A new adult candidate is one who first joined the list during the given year, without having been listed in a previous year. Previously listed candidates who underwent transplant and subsequently relisted are considered new. Active and inactive patients are included.




**All adult candidates on the heart transplant waiting list.** Adult candidates on the list at any time during the year. Candidates listed at more than one center are counted once per listing.

Figure HR 2: All adult candidates on the heart transplant waiting list. Adult candidates on the list at any time during the year. Candidates listed at more than one center are counted once per listing.




**Distribution of adults waiting for heart transplant by age.** Candidates waiting for transplant at any time in the given year. Candidates listed at more than one center are counted once per listing. Active and inactive candidates are included. Age is determined at the earliest of transplant, death, removal, or December 31 of the year.

Figure HR 3: Distribution of adults waiting for heart transplant by age. Candidates waiting for transplant at any time in the given year. Candidates listed at more than one center are counted once per listing. Active and inactive candidates are included. Age is determined at the earliest of transplant, death, removal, or December 31 of the year.




**Distribution of adults waiting for heart transplant by sex.** Candidates waiting for transplant at any time in the given year. Candidates listed at more than one center are counted once per listing. Active and inactive patients are included.

Figure HR 4: Distribution of adults waiting for heart transplant by sex. Candidates waiting for transplant at any time in the given year. Candidates listed at more than one center are counted once per listing. Active and inactive patients are included.




**Distribution of adults waiting for heart transplant by race and ethnicity.** Candidates waiting for transplant at any time in the given year. Candidates listed at more than one center are counted once per listing. Active and inactive patients are included.

Figure HR 5: Distribution of adults waiting for heart transplant by race and ethnicity. Candidates waiting for transplant at any time in the given year. Candidates listed at more than one center are counted once per listing. Active and inactive patients are included.




**Distribution of adults waiting for heart transplant by diagnosis.** Candidates waiting for transplant at any time in the given year. Active and inactive patients are included. Candidates listed at more than one center are counted once per listing.

Figure HR 6: Distribution of adults waiting for heart transplant by diagnosis. Candidates waiting for transplant at any time in the given year. Active and inactive patients are included. Candidates listed at more than one center are counted once per listing.