Alteration of the fibrinolytic system in patients with peripheral arterial occlusive disease.

Abstract

The fibrinolytic system may play an important role in the development and progression of peripheral arterial occlusive disease. The fibrinolytic system of the whole blood and a diseased leg was investigated in twenty men with chronic peripheral atherosclerotic occlusive arterial disease (PAOD, clinical stage II according to Fontaine), aged from 46 to 66 years (x = 55.3) [symbol: see text]. The diagnosis of PAOD was established by clinical examination and segmental systolic blood pressure measurements using a Doppler ultrasound detector. Twenty age-matched (x = 53.4) male volunteers with normal arterial circulation of the lower limbs and without risk factors of atherosclerosis, served as controls. In both groups fibrinolytic system was investigated in basal conditions and during provocation. Release of tissue-type plasminogen activator (t-PA) was provoked by 20 min venous occlusion of the arm and the leg and by infusion of DDAVP (1-desamino-8-D-arginine-vasopressin, 0.4 ug/kg of body weight). Blood samples were obtained from the arm and the leg before and after each stimulus. The fibrinolytic parameters: euglobulin clot lysis time, t-PA activity (amidolytic assay) and antigen (ELISA) and t-PA inhibitor (PAI) activity (amidolytic assay) were determined. With the exception of a boderline increase in PAI activity in patients, no other differences between the two groups were observed in basal conditions. The most prominent deterioration of the fibrinolytic system detected in male PAOD patients was a significantly higher residual PAI activity registered during venous occlusion of the arm and two minutes after combined stimulation. Two minutes after combined stimulation (DDAVP and venous occlusion of the arm) significantly lower t-PA activity was observed in patients. In patients t-PA antigen response to venous occlusion and DDAVP was not significantly different from the response observed in healthy volunteers. The fibrinolytic response of the leg to venous occlusion was poor and after DDAVP application it was comparable to the arm. The fibrinolytic response of the diseased leg in men was not significantly different from the healthy leg. The results of our study indicate that alteration of the fibrinolytic system in atherosclerotic disease is predominantly a generalised phenomenon and is not directly related to a local atherosclerotic process.