Heart transplantation equitable distribution of donor hearts
Editor(s)-in-Chief: C. Michael Gibson, M.S., M.D.; Associate Editor-In-Chief: Cafer Zorkun, M.D., Ph.D. [1]
Equitable Distribution of Donor Hearts to those Awaiting Transplantation and the Process of Being Listed for a Transplant
In order to assure that access to donor hearts is equitably distributed, the United Network for Organ Sharing (UNOS), was created. In general, patients who are hospitalized and require ongoing administration of parenteral inotropic agents are at highest risk of death, and are placed at the highest priority on the list of potential recipients. The following factors are used in assigning the priority for transplantation:
- The level of acuity of the patient's condition (sicker patients are higher on the list)
- The time the patient has waited on the list (patients who have waited longer are higher on the list)
- Duration of ischemic time anticipated when a donor heart does become available (assessed in increments of 500 miles between donor and recipient hospitals)(patients who are located closer to the donor heart are higher on the list)
Some patients may be moved down the list or they may be taken off of the list (delisted). About 5% of patients are delisted because they improve with medical therapy. The prognosis of patients who have been delisted is controversial. The largest study to date of 100 patients indicates that delisted patients may have a slightly poorer long-term prognosis than those patients who are transplanted. [1] While early survival was better among those patients who were delisted, survival after 30 months tended to be better among patients who were transplanted. Among delisted patients, the mean duration of survival was 7.7 years, and 94%, 55% and 28% of patients were event-free at 1, 5, and 10 years respectively. Although data is lacking, it has been hypothesized that survival could be further improved among delisted patients to 45% at 10 years if a defibrillator or AICD was implanted.
The predictors of death within two months of being placed on a transplant list among status 1 candidates include [2]:
- Inotropic and intra-aortic balloon pump support
- Pulmonary capillary wedge pressure >20 mm Hg
- UNOS status 1A
- Mechanical ventilation
- Serum creatinine >1.5 mg/dl
- Failed cardiac transplant
- Valvular cardiomyopathy
- Age >60 years
- Caucasian ethnicity
- Weight ≤70 kg
- Lack of an AICD on the day of listing
The mortality among children and young adults < 18 years of age who are awaiting transplant was 17% between 1999 and 2006 and is higher than adults. The majority of the deaths occurred in those children who weighed 10-15 Kg.
References
- ↑ Hoercher KJ, Nowicki ER, Blackstone EH, Singh G, Alster JM, Gonzalez-Stawinski GV, Starling RC, Young JB, Smedira NG (2008). "Prognosis of patients removed from a transplant waiting list for medical improvement: implications for organ allocation and transplantation for status 2 patients". The Journal of Thoracic and Cardiovascular Surgery. 135 (5): 1159–66. doi:10.1016/j.jtcvs.2008.01.017. PMID 18455599. Unknown parameter
|month=ignored (help) - ↑ Lietz, K, Miller, LW. Improved survival of patients with end-stage heart failure listed for heart transplantation: analysis of organ procurement and transplantation network/U.S. United Network of Organ Sharing data, 1990 to 2005. J Am Coll Cardiol 2007; 50:1282.