The Journal of Heart and Lung Transplantation
International Society for Heart and Lung Transplantation.

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

Published:September 15, 2021DOI:


      The United States National Organ Procurement Transplant Network (OPTN) implemented changes to the adult heart allocation system to reduce waitlist mortality by improving access for those at greater risk of pre-transplant death, including patients on short-term mechanical circulatory support (sMCS). While sMCS increased, it is unknown whether the increase occurred equitably across centers.


      The OPTN database was used to assess changes in use of sMCS at time of transplant in the 12 months before (pre-change) and after (post-change) implementation of the allocation system in October 2018 among 5,477 heart transplant recipients. An interrupted time series analysis comparing use of bridging therapies pre- and post-change was performed. Variability in the proportion of sMCS use at the center level pre- and post-change was determined.


      In the month pre-change, 9.7% of patients were transplanted with sMCS. There was an immediate increase in sMCS transplant the following month to 32.4% - an absolute and relative increase of 22.7% and 312% (p < 0.001). While sMCS use was stable pre-change (monthly change 0.0%, 95% CI [-0.1%,0.1%]), there was a continuous 1.2%/month increase post-change ([0.6%,1.8%], p < 0.001). Center-level variation in sMCS use increased substantially after implementation, from a median (interquartile range) of 3.85% (10%) pre-change to 35.7% (30.6%) post-change (p < 0.001).


      Use of sMCS at time of transplant increased immediately and continued to expand following heart allocation policy changes. Center-level variation in use of sMCS at the time of transplant increased compared to pre-change, which may have negatively impacted equitable access to heart transplantation.


      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to The Journal of Heart and Lung Transplantation
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


      1. Organ Procurement and Transplantation Network. Modify adult heart allocation 2016 2nd round. 2016, December.Available at: Accessed July 11, 2020.

        • Meyer DM
        • Rogers JG
        • Edwards LB
        • et al.
        The future direction of the adult heart allocation system in the United States.
        Am J Transplant. 2015; 15: 44-54
      2. Callahan, LR. Proposal to Modify the Adult Heart Allocation System. 2016. Available at: Accessed July 19, 2019; 2016.

        • Cogswell R
        • John R
        • Estep JD
        • et al.
        An early investigation of outcomes with the new 2018 donor heart allocation system in the United States.
        J Heart Lung Transplant. 2020; 39: 1-4
        • Hanff TC
        • Harhay MO
        • Kimmel SE
        • et al.
        Trends in mechanical support use as a bridge to adult heart transplant under new allocation rules.
        JAMA Cardiol. 2020; 5: 728-729
        • Parker WF
        • Chung K
        • Anderson AS
        • Siegler M
        • Huang ES
        • Churpek MM
        Practice changes at U.S. Transplant centers after the new adult heart allocation policy.
        J Am Coll Cardiol. 2020; 75: 2906-2916
        • Bernal JL
        • Cummins S
        • Gasparrini A
        Interrupted time series regression for the evaluation of public health interventions: a tutorial.
        Int J Epidemiol. 2017; 46: 348-355
        • Kontopantelis E
        • Doran T
        • Springate DA
        • Buchan I
        • Reeves D
        Regression based quasi-experimental approach when randomisation is not an option: interrupted time series analysis.
        BMJ. 2015; 350: h2750
        • Linden A
        Conducting interrupted time-series analysis for single- and multiple-group comparisons.
        Stata J. 2015; 15: 480-500
        • Borza T
        • Oreline MK
        • Skolarus TA
        • et al.
        Association of the hospital readmissions reduction program with surgical readmissions.
        JAMA Surg. 2018; 153: 243-250
        • Linden A
        A comprehensive set of postestimation measures to enrich interrupted time-series analysis.
        Stata J. 2017; 17: 73-88
        • Varshney AS
        • Berg DD
        • Katz JN
        • et al.
        Use of temporary mechanical circulatory support for management of cardiogenic shock before and after the United Network for organ sharing donor heart allocation system changes.
        JAMA Cardiol. 2020; 5: 703-708
      3. United Network for Organ Sharing. Mission, Vision and Values. Available at: Accessed June 27, 2020.

      4. United Network for Organ Sharing. Strategic Goals. Available at: Accessed June 27, 2020.

      5. Ethical Principles in the Allocation of Human Organs. Available at: Accessed Febuary 5. 2021.

        • Mohan S
        • Chiles MC
        Achieving equity through reducing variability in accepting deceased donor kidney offers.
        Clin J Am Soc Nephrol. 2017; 12: 1212-1214
        • Schulze PC
        • Kitada S
        • Clerkin K
        • Jin Z
        • Mancini DM
        Regional differences in recipient waitlist time and pre- and post-transplant mortality after the 2006 United Network for Organ Sharing policy changes in the donor heart allocation algorithm.
        JACC Heart Fail. 2014; 2: 166-177
        • Renlund DG
        • Taylor DO
        • Kfoury AG
        • Shaddy RS
        New UNOS rules: historical background and implications for transplantation management. United Network for Organ Sharing.
        J Heart Lung Transplant. 1999; 18: 1065-1070
        • Colvin-Adams M
        • Valapour M
        • Hertz M
        • et al.
        Lung and heart allocation in the United States.
        Am J Transplant. 2012; 12: 3213-3234
        • Parker WF
        • Garrity Jr., ER
        • Fedson S
        • Churpek MM
        Trends in the use of inotropes to list adult heart transplant candidates at status 1A.
        Circ Heart Fail. 2017; 10e004483
      6. Equity in Access to Transplant Dashboard. Available at: Accessed September 11, 2020.

        • Stewart DE
        • Wilk AR
        • Toll AE
        • et al.
        Measuring and monitoring equity in access to deceased donor kidney transplantation.
        Am J Transplant. 2018; 18: 1924-1935
      7. HednaotEiAtTdAa, Available at: Accessed on July 21, 2021.

        • Varshney AS
        • Hirji SA
        • Givertz MM
        Outcomes in the 2018 UNOS donor heart allocation system: a perspective on disparate analyses.
        J Heart Lung Transplant. Published online August 26,. 2020; (S1053-2498(20)31701-0.