MODIFICATIONS OF BIOLOGICAL PARAMETERS DURING TREATMENT OF PULMONARY EMBOLISM BY A VERY LOW MOLECULAR HEPARIN FRAGMENT (CY 222)

45 patients with pulmonary embolism (PE) were treated by a very low molecular weight heparin fragment (CY 222, Institut CHOAY - France) in an open range dose study. Patients were included into three groups (I, II and III) and received respectively 500, 750 or 1000 IC (Institut Choay) antiXa units/ kg/day by continuous intravenous infusion for ten days. The laboratory screen carried out at Day 0 and at 2 - 8 - 12 - 24 - 36, 48 hours and then every day until Day 10, included : Platelet count, Thromboelastography (TEG) on platelet rich plasma (PRP), Amidolytic assays for anti Xa (CBS 3139 STAGO) and anti Ila (S2238 KABI) activities (Calibration with Hepanorm STAGO), Heptest (Diamed, France), Amidolytic assay for tissue plasminogen activator (t-PA) and its inhibitor (PAI, Verheijen's method). Results showed no modification of platelet count and t-PA or PAI levels; An hypocoagulabi 1 ity was demonstrated with TEG on PRP (r+k > 35 mm) in 20 cases (3 patients from group III with haemorrhagic manifestations and 17 cases from groups II and III without complication). Anti-IIa activities were always lower than 0.15 U/ml. Anti-Xa activities and Heptest (Control adult values = 12.75 sec + 1.15) were (Mean + SD):

Any significant biological difference between patients who have good or poor clinical results was observed, excepted for 1 patient who had a high level of PAI at Day 0 and recurrence of PE.