Thrombin and platelet inhibition with low-dose calcium-heparin in comparison with ASA in patients with peripheral arterial occlusive disease at Leriche-Fontaine IIb class.

Sixty patients with a mean age of 64 years (range 57-77 years), 55 males and 5 females, with peripheral arterial occlusive disease (PAOD) at Leriche-Fontaine IIb class were randomly allocated to receive either subcutaneous calcium-heparin (12,500 IU once daily) or oral acetylsalicylic acid (ASA) (300 mg twice daily), each given for 3 months, followed by a 6-month follow-up period during which no treatment was given. The following parameters were evaluated before randomization, after 1 and 3 months of therapy and after 1, 3 and 6 months of follow-up: pain-free walking distance (PWD), maximum walking distance (WDmax), systolic and diastolic blood pressure, posterior tibial arterial pressure and ankle/arm index at rest and after exercise (treadmill), transcutaneous gas analysis at rest (TcPO2). Under both treatments a statistically significant increase (p < 0.01) in PWD/WDmax was observed after 3 months of therapy. Calcium-heparin was slightly but significantly more effective than ASA in prolonging WDmax (p < 0.05) after 3 months of therapy. Both treatment groups maintained the clinical improvement after 6 months of follow-up without any difference between each-other. Both treatments resulted in a statistically significant increase in TcPO2 and decrease in plasma fibrinogen but under calcium-heparin treatment these modifications were doubled in comparison with ASA (p < 0.01 and p < 0.05, respectively for TcPO2 and fibrinogen). The sustained effects on these parameters after 6 months of follow-up could suggest a more direct and multifactorial activity of calcium-heparin on microcirculation.(ABSTRACT TRUNCATED AT 250 WORDS)