Predicting the outcome of heart transplantation from expanded-criteria donors using regression analysis

There is a growing need for tools that enable objective assessment of donor heart quality. One such approach is the use of regression models incorporating donor and recipient risk factors to predict surgical outcomes and potentially expand the donor pool by increasing the number of transplantations.

Objective: to develop a model for estimating the total risk of one-year mortality in recipients using different categories of expanded-criteria donors (ECDs).

Materials and methods. The study included 1,500 recipients who underwent orthotopic heart transplantation (OHT) at Shumakov National Medical Research Center of Transplantology and Artificial Organs over an 11-year period, from January 1, 2011, to December 31, 2021. The cohort comprised 1,281 men (85.4%) and 219 women (14.6%), aged 9 to 78 years (median age 49.0 [38.0–56.0] years). The heart transplants performed (n = 1,500) were divided into two clinical groups: group 1 (main group) comprised recipients who underwent OHT from ECDs (n = 1,060; 70.6%); group 2 (control group) included recipients who underwent OHT from standard-criteria donors (n = 440; 29.4%). Donor heart suitability for transplantation was assessed according to the 2023 criteria of the International Society for Heart and Lung Transplantation (ISHLT).

Results. Donor- and recipient-related indicators were initially evaluated using univariate regression analysis. The final multivariate regression model included five donor-related factors – donor–recipient weight mismatch, donor age, high-dose cardiotonic therapy, coronary stenosis, and prolonged graft ischemia – and four recipient-related factors – total bilirubin >40 μmol/L, creatinine >110 μmol/L, international normalized ratio (INR) >1.4, and pre-transplant peripheral veno-arterial extracorporeal membrane oxygenation (pVA-ECMO). The highest odds ratios were observed for donor age, coronary stenosis, graft ischemia time exceeding 6 hours, and pre-transplant pVA-ECMO support. The predicted one-year mortality rate calculated using regression analysis showed a strong correlation (R = 0.827; p < 0.001) with the observed one-year mortality rate. Long-term survival was also analyzed across risk groups, with the worst outcomes observed in the high-risk group.

Conclusion. The proposed statistical model provides a reliable prognostic accuracy for both early and long-term post-transplant survival. Its application at the stages of donor heart evaluation and donor–recipient matching may facilitate the use of a broader donor pool while enabling an objective assessment of recipient prognosis.

1. Wang Y, Cai J, Sun Y, Zhang J, Xie F, Alshirbini MH et al. Extended donor criteria in heart transplantation: a retrospective study from a single Chinese institution. J Thorac Dis. 2018 Apr; 10 (4): 2153–2165. doi: 10.21037/jtd.2018.03.149. PMID: 29850119; PMCID: PMC5949496.

2. Smits JM, De Pauw M, de Vries E, Rahmel A, Meiser B, Laufer G, Zuckermann A. Donor scoring system for heart transplantation and the impact on patient survival. J Heart Lung Transplant. 2012 Apr; 31 (4): 387–397. doi: 10.1016/j.healun.2011.11.005.

3. Guglin M. How to increase the utilization of donor hearts? Heart Fail Rev. 2015 Jan; 20 (1): 95–105. doi: 10.1007/s10741-014-9434-y. PMID: 24858482.

4. Velleca A, Shullo MA, Dhital K, Azeka E, Colvin M, DePasquale E et al. The International Society for Heart and Lung Transplantation (ISHLT) guidelines for the care of heart transplant recipients. J Heart Lung Transplant. 2023 May; 42 (5): e1–e141. doi: 10.1016/j.healun.2022.10.015. Epub 2022 Dec 20. PMID: 37080658.

5. Russo MJ, Davies RR, Hong KN, Chen JM, Argenziano M, Moskowitz A et al. Matching high-risk recipients with marginal donor hearts is a clinical effective strategy. Ann Thorac Surg. 2009 Apr; 87 (4): 1066–1071. doi: 10.1016/j.athoracsur.2008.12.020.

6. Eisen HJ. Adverse outcomes from the use of older donor hearts in cardiac transplant recipients: the pros and cons of expanded donor criteria. J Am Coll Cardiol. 2004 May 5; 43 (9): 1562–1564. doi: 10.1016/j.jacc.2004.02.005.

7. Khasati N, Barnard J, Bittar MN, Machaal A, Waterworth P, Yonan N. Donor heart selection: Wythenshawe experience. Transplant Proc. 2005 Mar; 37 (2): 1331– 1332. Cite this article as: Wang Y, Cai J, Sun Y, Zhang J, Xie F, Alshirbini MH, Shi J, Dong N. Extended donor criteria in heart transplantation: a retrospective study from a single Chinese institution. J Thorac Dis. 2018; 10 (4): 2153–2165. doi: 10.21037/jtd.2018.03.149.

8. Wittwer T, Wahlers T. Marginal donor grafts in heart transplantation: lessons learned from 25 years of experience. Transpl Int. 2008 Feb; 21 (2): 113–125. doi: 10.1111/j.1432-2277.2007.00603.x.