IMPAIRMENT OF FIBRINOLYTIC POTENTIAL IN LONG-TERM STEROID TREATMENT AFTER HEART-TRANSPLANTATION

Thrombotic complications constitute an important risk in transplant re cipients, in whom a hypercoagulable state and hypofibrinolysis have be en associated with immunosuppressive treatment, especially with cyclos porine. In no case have clotting and fibrinolytic abnormalities been c orrelated with steroid immunosuppression, even though steroids were al ways administered. Previous studies found a relationship between hyper corticism and hypofibrinolysis both in Gushing's disease and after ren al transplantation. The aim of this investigation was to compare fibri nolytic potential using the venous occlusion test in two similar group s of heart transplant patients treated with or without steroids. Euglo bulin lysis time, tissue-type plasminogen activator and plasminogen ac tivator inhibitor-1 (PAI-1) activities, and antigens were determined b efore and after the venous occlusion test, A reduced fibrinolytic pote ntial (significant prolongation of lysis time) due to a significant in crease in PAI-1 activity and antigen levels was found in heart transpl ant patients treated with steroids, as compared with patients without steroid treatment and control subjects, The prevalence of reduced fibr inolytic potential was 69.2% (18 cases) in the steroid-treated group a nd 34.8% (8 cases) in the non-steroid-treated group. In every case, th e impaired fibrinolytic potential was due to high basal PAI-1 levels. Our results are compatible with the presence of a hypofibrinolytic sta te secondary to long-term steroid treatment, In heart transplant recip ients, steroid-induced hypofibrinolysis may constitute a further risk factor for thrombotic disease.