Treatment of acute myocardial infarction with subcutaneous heparin at low doses.

Heparin has been used intensively in the treatment of acute myocardial infarction and preinfarction angina (PA) at full doses as a single drug by us. However, heparin may be used at smaller doses for similar purposes. These doses are not exactly anticoagulant, even though they reduce blood hypercoagulability, and act mainly in an antithrombotic capacity. We studied 529 patients with acute myocardial infarction, of whom 262 were treated with subcutaneous heparin at low doses (5000 IU every 12 h) and 267 received conventional therapy without antithrombotic drugs. Heparin used was Heparina (Abbott) and Liquemine (Roche), in vials with the equivalence 1 cm3 = 50 mg = 5000 IU. Blood rheologic factors (thromboelastography, platelet adhesiveness, total blood viscosity, and number of platelets) were determined in all patients, those treated with heparin at low doses and also the control group, before and after the 30-day treatment period. Diagnosis was based on clinical symptoms, laboratory studies, and electrocardiogram examination. In both the 262 patients treated with heparin at low doses and in the control group of 267 patients, baseline values of rheological factors were high. After 30 days (i.e., after study completion) these high values which are statistically significant compared with normal values, with p less than 0.0001 for both groups, remained constant in the control group who did not receive heparin. On the contrary, in the group treated with heparin at low doses, all these factors changed. Heparin provides protection against thrombosis by increasing the negative charge of the vessel wall and by other reactions at the endothelial surface. Heparin requires a plasmatic component called antithrombine III.(ABSTRACT TRUNCATED AT 250 WORDS)

[Treatment of neurological forms of Argentinian hemorrhagic fever with cytarabine]. / Traitement des formes nerveuses de la fièvre hémorragique argentine par la cytarabine.

The effects of cytarabine on neurological forms of Argentina Hemorrhagic Fever were evaluated in 125 patients. The mortality was 12.88 per cent compared to 61.40 per cent in untreated patients. (p less than 0.0001). The efficiency of this treatment depends on its early application. No side effect was observed.

[Treatment of Argentine hemorrhagic fever with convalescent's plasma. 4433 cases]. / Traitement de la fièvre hémorragique argentine par le plasma de convalescent. 4,433 cas.

During the 23 consecutive annual epidemics of Argentine haemorrhagic fever observed from 1959 to 1983, a group of 4,433 patients were treated at Junin (Argentina) with convalescent's plasma; the overall mortality rate was 3.29%. In 1958, before convalescent's plasma was used, the mortality rate in 448 patients who received the conventional treatment was 42.85%. The difference between the two groups is highly significant and demonstrates the value of convalescent's plasma in the treatment of the disease.

[Medical treatment of the threat syndrome with heparin. Long-term prospective study]. / Traitement médical du syndrome de menace par l'héparine. Etude prospective au long cours.

A 19-year study of 119 patients stricken with a threat syndrome and treated with heparin is presented. The average observation period is 10.15 years. The total mortality was 33.94 per cent. The cumulative annual mortality was 1.79 per cent. The life expectancy for treated patients was identical to that of the general population in Argentina. The survivors (60.51% of the cases) were either asymptomatic (45.83%) or presented varying cardiac pathology (54.17%).

Heparin effect on plasma fibrinogen in the thrombophilic syndrome.

The effects of heparin were studied in a group of 42 patients with preinfarction angina (PA) and acute myocardial infarction (AMI) whose plasma fibrinogen was increased. Plasma fibrinogen was measured by the turbidimetric method in timol turbidimetric units. Statistically significant results proved that heparin reduces the plasma fibrinogen progressively over a treatment period of 6 weeks. During the first three weeks a dose of 1 cc (50 mg or 5000 IU) was given by intravenous injection at 6-h intervals, this was followed by a dose of 2 cc (100 mg or 10,000 IU) given by subcutaneous injection at 12-h intervals for a further three weeks. Hyperfibrinogenemia is perhaps one of the most important factors in the thrombophilic syndrome, and at the same time it is one of the fundamental physiopathological alterations observed in AMI and PA. Because heparin reduces hyperfibrinogenemia it has a beneficial effect in these diseases.

Heparin effect on blood viscosity.

The effect of heparin on blood viscosity was investigated in a group of patients with acute myocardial infarction (AMI) and preinfarction angina (PA), whose blood viscosity was elevated. Viscosity was measured with Cannon, Fenske, and Routine viscometers. Kinematic viscosity, bath and whole blood, plasma, and serum viscosity were determined as well as dependent parameters (fibrinogen, serum proteins, number of platelets, and hematocrit). All of them were found to increase, and it was significantly proved that intravenous heparin immediately decreased plasma viscosity, but has a lesser effect on serum and whole blood viscosity. A dose of 1 cc = 50 mg = 5000 IU intravenous heparin, will maintain this decrease for a month. In our four-week-study, 1 cc i.v. heparin was administered at 6-hour intervals for the first 2 weeks, and 2 cc heparin subcutaneous injections were administered at 12-hour intervals for the next 2 weeks. We found that heparin also decreased fibrinogen, hematocrit, serum alpha 2 globulin, and number of platelets. Hyperviscosity, hypercoagulability, and the increase of platelet adhesiveness arae some of the most important physiopathological alterations of AMI and PA. The decrease of blood viscosity due to heparin is one of the most important and beneficial effects of it in this pathology.

Immunogenicity of A/USSR (H1N1) subunit vaccine in unprimed young adults.

A clinical and serological study was performed on 267 of 636 volunteers vaccinated against Argentine hemorrhagic fever with the XJCl3 attenuated strain of Junin virus seven to nine years earlier, in order to determine their long-term evolution. This study included a clinical examination, a chest roentgenogram, an electrocardiogram, and the following laboratory determinations: white and red cell count, number of platelets, hematocrit, hemoglobin, sedimentation rate (Katz index), urea, nitrogen, glucose concentration, cholesterol, GOT, GPT, gamma GT, alkaline phosphatase, cholinesterase, and total bilirubin. Neutralization reactions were performed to determine presistence of antibody levels. All clinical and laboratory findings were within normal limits, excluding a long-term pathology attributable to the virus. Of 165 tested sera, 153 (90.3%) had detectable levels of neutralizing antibodies, and the rest had no antibodies after this time. Although these people live in the endemic area, it is considered that only the 9% that had increased antibody levels had suffered a reinfection during the seven- to nine-year period, which acted as a booster. This figure aproximately coresponds to the subclinical infection value found in the region. In the rest, the persistence of antibodies is attributed to the immunization achieved with the vaccine employed.

Argentine hemorrhagic fever: early diagnosis by immunofluorescence.

A procedure that allows to ascertain a diagnosis of Argentine Hemorrhagic Fever (AHF) as early as 24-48 hours after onset of symptoms is described. An immunofluorescent (IF) test on round cells of urinary sediment was employed. The procedure was assayed on 31 patients with febrile syndrome during epidemic peaks of 1975-1976. It was positive in 19 and negative in 12 cases. The 19 positive cases were confirmed AHF by clinical follow up and serology. From 12 negative cases, 8 belonged to other etiologies and 2 were confirmed AHF. The usefulness of the procedure for early diagnosis is emphasized.