Blood rheology after renal transplantation.

Cardiovascular complications seriously affect posttransplant survival in patients after successful renal transplantation. Abnormalities in blood rheology may contribute to these complications. Therefore, we studied the blood rheology before and during a 1-year observation period after grafting in 9 patients by serial measurements of fibrinogen, red cell aggregation, hematocrit, spontaneous platelet aggregation, and plasma viscosity. Prior to grafting, fibrinogen and red cell aggregation were found to be increased in patients on regular hemodialysis as compared with healthy controls, whereas hematocrit and platelet aggregation were markedly reduced. After successful transplantation, the platelet aggregation progressively rose together with the hematocrit, while fibrinogen and red cell aggregation remained abnormally high. Our findings suggest that abnormal blood rheology in patients with chronic renal failure does not improve in response to successful renal transplantation: fibrinogen and red cell aggregation remain abnormally high; further, the overall blood flow properties are supposed to deteriorate due to the postoperative increase in hematocrit and spontaneous platelet aggregation. Adverse rheological conditions thus resulting may contribute to the increased frequency of vascular events observed in transplanted patients.