[Treatment of acute pulmonary embolism with a low molecular weight heparin by the intravenous route. Study of the optimal dosage]

Experimental studies on rabbits have shown that CY 222, a low molecular weight heparin (mean: 2.500 daltons), has the anti-thrombosis properties of heparin but reduces the risk of haemorrhage in optimal doses of 1.000 AXa IC (Institut Choay) units/kg/day. The safety and effectiveness of CY 222 were tested in 47 patients presenting with a less than 5 days' old pulmonary embolism. The patients were divided into three groups according to dosage: group I (n = 16) received 500 AXa ICu/kg/day; group II (n = 17), 750 AX ICu/kg/day, and group III (n = 14), 1.000 AXa ICu/kg/day. The drug was administered by continuous intravenous infusion during 10 days. Its effectiveness was assessed from the Miller index calculated on conventional pulmonary angiograms on days 0, 5 and 10. On the 10th day of treatment, the percentage of revascularization was similar in all three groups (group I 65.9 +/- 9.9 p. 100; group II 71 +/- 6.8 p. 100; group III 68 +/- 8.5 p. 100), but the improvement was significantly more rapid in group III patients. Embolism recurred in 5 cases (2 in group I, 1 in group II, 2 in group III) and was fatal in 1 case (group I). Haemorrhagic complications were noted in 3 cases (group III patients). Except for thromboelastography, all coagulation tests were unmodified by CY 222. The anti Xa and the (very low) anti IIa activities of the drug were directly related to the doses administered.(ABSTRACT TRUNCATED AT 250 WORDS)

Levels and plasma distribution of free and C4b-BP-bound protein S in human fetuses and full-term newborns

Levels and plasma distribution of protein S were measured on umbilical cord plasmas from 25 normal full-term newborns and 25 normal fetuses which were between 20 and 31 weeks of gestation. Fetal blood samples were obtained by direct puncture of the umbilical vein under high resolution real-time ultrasound. Total and Free protein S levels were found to be lower in all fetuses and newborns as compared to normal adults. The calculated ratio Total protein S/Free protein S and crossed immunoelectrophoresis patterns indicate that protein S circulates essentially in the free form in fetuses and newborns. These data may be explained by the low levels of C4b-binding protein observed at these stages of development.

[Role of urokinase in the acute phase of myocardial infarction]

The prourokinase-urokinase system physiologically contributes to fibrinolysis activation. It is therefore rational to envisage the use of urokinase in thrombotic diseases, and notably in the acute phase of myocardial infarction (MI) where coronary thrombosis is virtually constant. The main studies on this subject were published in 1975 and in 1985, thus reflecting the changes in therapeutic concepts that have occurred during these 10 years. The older studies concerned patients who were admitted within the first 12 hours of MI and had no early angiographic examination; the results were evaluated indirectly on clinical and enzymatic criteria and on the regression of electrical signs of myocardial suffering. The more recent studies concern patients who are treated at an early stage, often within the first 3 hours of the accident, on the basis of experimental data which favoured early coronary reperfusion as a means of protecting the myocardium; in these studies coronary arteriography is performed immediately after the thrombolytic treatment; computer-assisted studies of the left ventricular function are also carried out, so that the results of thrombolysis are expressed in terms of coronary patency and improvement in segmental kinetics. The results of these different sets of studies have proved to be similar with time. Urokinase, notably when injected intravenously, has a beneficial effect in the acute phase of MI when compared to the conventional treatment. The coronary reperfusion obtained with urokinase is favourable to the myocardium, and the sooner it occurs the better. This benefit is demonstrated by clinical, electrical, enzymatic and angiographic data. Thus, despite its cost, urokinase remains useful in the treatment of MI, notably because it is well tolerated.(ABSTRACT TRUNCATED AT 250 WORDS)

Determination of platelet antigens and glycoproteins in the human fetus

The autosomal recessive transmission of Glanzmann's thrombasthenia (GT) and Bernard-Soulier syndrome (BSS), together with requests of families who already had children with these diseases, prompted us to investigate the feasibility of their antenatal diagnosis. The preliminary step leading to the early detection of GT or BSS was to characterize, in the normal human fetus, the platelet antigens and glycoproteins (GPs) and to define their normal amounts on the membrane surface. Blood samples from 32 fetuses between 18 to 26 weeks of gestation were collected by direct puncture of the umbilical vein using an ultrasound-guided needle. Polyclonal antibodies from human origin directed against PLA1, Leka antigens, and the GPIIb IIIa complex (IgGL), or murine monoclonal antibodies specific for GPIb (AN51, 6D1), GPIIIa (AP-3), or GPIIb IIIa (AP-2) were studied using platelet suspension immunofluorescence tests. The binding of each antibody was quantified using a cytofluorograph (Ortho 50H). PLA1 and Leka antigens were expressed in normal amounts on fetal platelets as early as 16 weeks of intrauterine life. The GPIIb IIIa complex quantified by polyclonal or monoclonal antibodies was in the same range in fetuses (IgGL = 427 +/- 23 AUF, AP-2 = 459.5 +/- 8.5; AP-3 = 536 +/- 14) and in adults (IgGL = 420 +/- 30; AP-2 = 498 +/- 11; AP-3 = 515 +/- 13). The platelet binding of antibodies that recognized GPIb was higher in fetuses (AN51 = 491.5 +/- 14; 6D1 = 479 +/- 15) than in adults (AN51 = 426.5 +/- 9; 6D1 = 449 +/- 8.7). These results suggest that immunological techniques can be applied as early as 18 weeks of gestation for the antenatal diagnosis of GT and BSS.

A new method of ventilation with a mixture of helium and oxygen in the management of congenital diaphragmatic hernia. A preliminary study

To prevent the severe prognosis of pulmonary hypoplasia in congenital diaphragmatic hernia, the authors developed a new method of ventilation, using a modulated mixture of helium and oxygen. Associated with a leptanalgesia (Chlorpromazine-Morphine), the authors observed with this method two good results. Efficiency of this technique has been confirmed by X-rays and successive pulmonary scintigraphies (Xenon 133).

The white clot syndrome or heparin associated thrombocytopenia and thrombosis (WCS or HATT) (26 cases)

The Authors report a new iatrogenic complication of preventive or curative standard heparinotherapy. This so called "white clot syndrome" or "Heparin associated thrombocytopenia and thrombosis" is an anatomico-clinical entity characterized by severe, multiple, recurrent, arterial and/or venous thromboembolic accidents which are sometimes fatal. They appear, paradoxically, under heparin treatment and are concomitant with thrombocytopenia (generally less than 100 10(9)/l). Antiplatelet immunoallergic phenomena, via type IgG antibodies, induced by heparin, are the most commonly admitted in physiopathology; however they remain controversial. Treatment of "WCS" includes urgent suppression of standard heparin, administration of antivitamin K, or the new generation of low molecular weight heparin. This series presents 26 cases of HATT treated by LMWH (CY 216 CHOAY). Severe complications must be surgically cured. Prevention of WCS or HATT is mandatory by the systematic survey of platelet count during heparinotherapy.

Treatment of heparin-associated thrombocytopenia and thrombosis with low molecular weight heparin (CY 216)

This report concerns 34 cases of heparin-associated thrombocytopenia in which standard heparin has been systematically replaced by LMW heparin CY 216 Choay. There were 21 women and 13 men, mean age, 69 years. Twenty-six of the 34 cases had thrombotic complications. All of the patients were treated by standard heparin of porcine mucosal origin, in most cases for prevention of deep vein thrombosis and pulmonary embolism. Twenty-six cases occurred along with orthopedic and traumatologic surgery (especially for total hip replacement, 15 cases). Four cases involved vascular surgery and three involved medical thrombotic disease. Standard heparin treatment was always replaced by LMW heparin CY 216. Initial doses were 0.30 ml three times daily, later increased to obtain global hypocoagulability. Surgical procedures (embolectomy and vena cava filter) were carried out when necessary. Five patients had thrombolytic treatment (urokinase) in conjunction with LMW heparin. The overall results were 31 recoveries, but with seven severe sequelae (three amputations and four hemiplegias) most often attributable to the first ischemic attack, and three deaths. For the last 16 patients, indirect platelet aggregation tests were performed (control platelet-rich plasma plus patient platelet-poor plasma plus LMW heparin): nine cases had negative tests, with nine recoveries and seven cases had positive tests, with five recoveries and two deaths.(ABSTRACT TRUNCATED AT 250 WORDS)