Evaluating the donor pool: impact of using hearts from donors over the age of 49 years

[Evaluation of the potential organ donor with special regards to heart donation]

Angesichts der auch in Österreich vorherrschenden Knappheit an verfügbaren Organspendern für Herztransplantationen erscheint es dringlich notwendig, eine Optimierung von Spenderevaluierung und Management zu diskutieren. In der vorliegenden Arbeit werden allgemeine Spenderkriterien und herzspezifische Parameter detailliert diskutiert und im Zusammenhang mit der internationalen Literatur dargestellt. Es wird der "marginale" und im Gegensatz dazu der "optimale" Organspender definiert. Das Spendermanagement wird besprochen, wobei neben der hämodynamischen Optimierung auch auf zusätzliche intensivmedizinische Aspekte eingegangen wird. Erst die exakte Evaluierung erlaubt die individuelle Zuteilung des Organs zum passenden Empfänger und stellt somit insbesondere bei marginalen Spendern die Grundlage eines Therapieerfolgs dar.

Results After Orthotopic Heart Transplantation Accepting Donor Hearts >50 Years: Experience at La Pitie Salpetriere, Paris

INTRODUCTION

We sought to examine the results of orthotopic heart transplantation accepting hearts from donors >50 years of age with special regard to the usefulness of peripheral extracorporeal membrane oxygenation for posttransplant graft dysfunction.

PATIENTS

Between January 2000 and December 2004, a total of 247 patients underwent orthotopic heart transplantation. In 143 patients (58%) the heart donor was <50 years (group I, mean age of donor hearts 36 +/- 11 years; range, 8-49 years). In 104 recipients (42%) the heart donor was >50 years (group II, mean age of donor hearts 56 +/- 15 years; range, 50-67 years). Pretransplant characteristics of the two groups showed no significant differences.

RESULTS

The in-hospital mortality was slightly increased in group II (24% vs 20% in group I, NS) and the 5-year survival rate significantly increased in group I (75% vs 63% in group II). Freedom from transplant vasculopathy after 3 years was similar in both groups (86% in group I vs 87% in group II). A total of 25 patients (17%) in group I and 27 patients (26%) in group II developed graft dysfunction. Eleven patients in group I and 10 patients in group II were treated using peripheral extracorporeal membrane oxygenation, whereas 3 of the 11 patients in group I and 5 of the 10 patients in group II were discharged following a complete recovery. Two patients in group I and 4 patients in group II were survivors beyond year.

CONCLUSION

In our experience it was possible to increase the cardiac donor pool by accepting allografts from donors >50 years of age in selected cases. The incidence of transplant vasculopathy was not increased, whereas in-hospital mortality was slightly higher. In our limited cohort, patients with older donor hearts was developed graft dysfunction profited from primary extracorporeal membrane oxygenation implantation, an indication that should be examined further without delay.

Donor and recipient-transforming growth factor-beta 1 polymorphism and cardiac transplant-related coronary artery disease

BACKGROUND

Transforming growth factor-beta1 (TGF-beta1) has been implicated in the pathogenesis of coronary vasculopathy following cardiac transplantation. The TGFB1 gene contains polymorphisms at positions +915* (Arg25Pro) and +869* (Leu10Pro) which may influence TGF-beta1 expression. We investigated the relationship between the development of coronary vasculopathy and the prevalence of these alleles in a cardiac transplant population.

METHODS

Vasculopathy was diagnosed at routine surveillance post-transplant coronary angiography. Using sequence-specific polymerase chain reaction we identified the TGFB1 +915* and +869* genotypes in 147 cardiac transplant recipients and 134 cardiac donors.

RESULTS

TGFB1 +915*C allele carriers (low producers) made up 10.5% of the recipient population but were significantly less likely to develop coronary vasculopathy (P=0.03). Median time to diagnosis was 6.0 years (3.9-8.72) in +915*C allele carriers compared to 2.75 years (2.10-4.22) in *G/G homozygotes (p=0.002). Pre- and 1 year post-transplant clinical variables were equivalent between the two groups. Multivariate analysis identified the recipient +915*G/G genotype (hazard ratio 2.96 (95% CI, 1.09-9.98); p=0.039), donor age (hazard ratio 1.05 (95% CI, 1.02-1.09); p=0.008) and number of acute rejection episodes of ISHLT grade 3 or greater in the first year (hazard ratio 1.12 (95% CI, 1.01-1.23); p=0.03) as significant predictors of vasculopathy. The recipient TGFB1 +869*, and both alleles in the donor, had no influence on vasculopathy development.

CONCLUSIONS

Recipient TGFB1 +915* genotype influences the development of cardiac transplant-related coronary vasculopathy. This gives an important insight to the pathophysiology of the disease. On the contrary, donor TGFB1 +915* and TGFB1 +869* polymorphisms do not appear to be important and cannot be used as genetic risk factors.

The challenge of managing the care of older heart transplant recipients

Age is perhaps the most controversial exclusion criterion for heart transplantation. One concern focuses on whether chronological or functional age is the better predictor of positive outcomes when considering heart transplantation for an elderly patient with end-stage heart disease. Another concern is related to the philosophical and ethical rationale for allocation of scarce resources to those near the end of a normal life expectancy. However, the number of people who are older than age 65 years and have received a donor heart has increased and will continue to due to aging of the people who received a transplant a decade ago, as well as the growing number of people who undergo heart transplantation after the age of 65. In either case, the nurse must be aware of age-related concerns in this vulnerable population.