Thromboembolism in heart transplantation: role of prothrombin G20210A and factor V Leiden.

Background: Thromboembolism has been reported as a frequent complication after cardiac transplantation. Many risk factors for thrombosis may explain this, such as metabolic alterations and the use of cyclosporine. In the general population, two single nucleotide polymorphisms (SNPs), factor V Leiden and prothrombin G20210A (PT G20210A), have been associated with a significant increase in the risk of thrombosis. However, these mutations have not been analyzed in cardiac transplant patients. We describe the protracted history of recurrent thromboembolism in a rare case of homozygosity for the PT G20210A variant. This prompted us to analyze the entire cardiac transplant cohort for the incidence of thromboembolic events and their association with these genetic polymorphisms.

Methods: We report the study of 84 cardiac transplant recipients. We retrospectively analyzed the frequency of thromboembolic episodes. The genotypes for FVL and PT G20210A were determined and correlated with those episodes.

Results: Our results confirm a very high incidence of thromboembolism in this population. We also found a significant increase in the likelihood of thromboembolism in subjects with the PTB G20210A variant (odds ratio 3.08; 95% confidence interval: 1.7-5.5).

Conclusions: The incidence of thromboembolic complications after heart transplantation is increased and may be related in part to genetic predisposition.