The incidence of aspirin resistance in heart transplantation recipients

Introduction: Coronary allograft vasculopathy can cause as many deaths as infections or rejection episodes within 3 years following heart transplantation.

Aim: To compare the aspirin resistance rate in an allograft heart transplantation population and in a control group by laboratory tests including the Aspirin-Resistant Patients Identification Test (ASPItest).

Material and methods: A total of 24 heart recipients (20 men and 4 women) at a mean age of 48 ±13 years who underwent routine clinical follow-up were consecutively enrolled in group 1.The control group consisted of 24 patients (19 men and 5 wo­men) at a mean age of 64 ±7 years waiting for coronary artery bypass grafting in our department. All patients were treated with a standard dose of 75 mg aspirin (ASA) daily.

Results: Aspirin resistance was evaluated by the Multiplate platelet function test. The ASPItest revealed a mean value of 27 ±22 U in the transplant group. Results above 30 U were obtained in 8 (34%) patients, with a mean value of 50.3 ±20.6 U, indicating aspirin resistance. In the control group ASPItest results above 30 U were obtained in 5 (20%) patients, with a mean value of 43.3 ±6.4 U.

Conclusions: There is a high incidence (34% vs. 20%, NS) of ASA resistance in heart transplantation recipients and in the general population, respectively.