[Evaluation of the efficacy of anti-arrhythmic drugs using a computer]. / L'évaluation de l'efficacité des drogues antiarythmiques à l'aide de l'ordinateur.

To palliate the deficiencies of the oscilloscopic monitoring of arrhythmias, an automatic system has been developed. It has been used during more than one year time in the Coronary Unit for supervision of patients and for study of the pharmacological effects of antiarrhythmic drugs.

Dobutamine effects on blood gases and hemodynamics in acute myocardial infarction with heart failure.

We studied the effects of dobutamine on blood gases, venous admixture and hemodynamics in ten patients suffering an acute myocardial infarction (AMI) with left heart failure. After one hour infusion of dobutamine (mean dose: 6.3 micrograms/kg X min) there was an increase in cardiac index (27%, P less than 0.005), and a decrease in pulmonary wedge pressure (13%, P less than 0.025) and right atrial pressure (25%, P less than 0.025). The increase in oxygen delivery (23%, P less than 0.005) and mixed venous oxygen tension (10%, P less than 0.01) were neither accompanied by significant change in low arterial oxygen tension nor in high venous admixture. We conclude that dobutamine improves hemodynamics and oxygen delivery in AMI without affecting existant intrapulmonary shunting.

[Experimental models for the pharmacologic study of anti-arrhythmia drugs]. / Modèles expérimentaux pour l'étude pharmacologique des anti-arythmiques.

In order to assess the value and therapeutic safety of an antiarrhythmic drug, it must be submitted to multiple tests, which reproduce as faithfully as possible the conditions observed in human pathology. The main experimental approaches are presented here: screening and control tests. For each test, the authors emphasize the various experimental factors limiting their interpretation and allowing the extrapolation to men.

[Short- and long-term prognosis of myocardial infarct. Contributions and limitations of the clinical aspects and non-invasive technics]. / Pronostic à court et à long terme de l'infarctus du myocarde. Apports et limitations de la clinique et des techniques non invasives.

Clinical variables and those obtained by non-invasive techniques were recorded in a series of 306 patients discharged from hospital after an acute myocardial infarction. We studied the prognostic value at 2 and 12 months of these variables (alive/dead). The results of simple clinical data were as discriminant as those from more elaborated techniques. When the prognostic value of the same data at 12 months was studied in those surviving for two months, most of the predictive variables lost their discriminant power. The study shows that the predictive value of many of the predischarge variables usually taken into account in the assessment of long term risk, does not extend beyond the first two months.

[Early exercise test after myocardial infarction]. / Epreuve d'effort précoce aprés infarctus du myocarde.

Exercise tests of coronary function at the tenth day of an uncomplicated myocardial infarction offer objective evaluation of short-term benefits of an early accelerated physical retraining program. They also allow better individual adaptation of exercises prescribed at the start of convalescence at home. Exercise test results show significant correlation with clinical data and bicycle ergometer tests carried out two months after infarction, with respect to physical aptitude, reasons for discontinuation of test and lethality risk two months after infarction. This suggests that exercise tests performed after the acute phase of myocardial infarction are of diagnostic and prognostic value.

[Value of serum immunoglobulin assays in early myocardial infarction]. / Intérêt du dosage des immunoglobulines sériques lors de l'installation d'un infarctus du myocarde.

Serum immunoglobulin (Ig) levels were assayed in 672 patients admitted for acute myocardial infarction with onset within 24 hours of hospitalization. Supranormal Ig levels (A > or = 300, G > or = 1,200) or subnormal Ig levels (M < 40 mg/100 ml) were seen in patients with one or several risk factors (diabetes mellitus, alcohol abuse) or a history of previous myocardial infarction. Patients with one or more Ig anomalies were more likely to exhibit unfavorable outcomes, including early death, suggesting that increased viscosity due to aggregation of Ig molecules may occur.

Effect of labetalol on preload in acute myocardial infarction with systemic hypertension.

We assessed the effects of labetalol on pulmonary wedge pressure (PWP) and other hemodynamic variables in 18 patients with acute myocardial infarction (AMI) and systemic hypertension (systolic blood pressure greater than 150 mm Hg). According to the initial value of PWP, the patients were separated into two groups of nine patients each: Group 1 (PWP greater than or equal to 15 mm Hg) and Group 2 (PWP less than or equal to 12 mm Hg). Labetalol was infused at increasing rates to lower systolic blood pressure below 130 mm Hg; this optimal rate (mean rates for Groups 1 and 2: 1.8 and 2.1 mg/min, respectively) was maintained for 1 h. Hemodynamic variables were measured before and after 1 h of infusion. Labetalol normalized blood pressure in both groups by a significant decrease in total systemic resistance [22% (p less than 0.001) and 13% (p less than 0.02)] and in cardiac index [17% (p less than 0.005) and 12% (p less than 0.02)]. While the hemodynamic responses were rather similar in both groups, the PWP decreased significantly (from 22 to 15 mm Hg, p less than 0.01) in Group 1, but did not change significantly in Group 2 (from 7 to 10 mm Hg, NS). The possible mechanisms behind these different responses are discussed. We conclude that labetalol is an effective drug for treating systemic hypertension in AMI which acutely decreases total systemic resistance and preload in patients with moderate left ventricular failure.

Limitations on the prognostic value of predischarge data after myocardial infarction.

Clinical variables and those obtained by non-invasive techniques were studied prospectively in a series of 306 patients discharged from hospital after an acute myocardial infarction. The predictive value of the data at two and 12 months was assessed by univariate and multivariate analyses. The best correlation was found for age, hypertension, bundle branch block, early and late heart failure, x ray cardiothoracic ratio, digoxin use, the number of metabolic equivalents reached during the stress test, echocardiographic wall motion score index, left ventricular end diastolic diameter, left ventricular ejection fraction, and the presence of an aneurysm. The prognostic value of the same data at 12 months was studied in those surviving for two months. There was a noticeable decline in the relative risk of all but two of the factors (number of metabolic equivalents, ventricular arrhythmias). All of the predictive variables except the x ray cardiothoracic ratio, number of metabolic equivalents, and the presence of an aneurysm lost their discriminant power. The explanation for this is the strength of statistical relations of these variables with the outcome at two months. They continued to influence the score at 12 months even when the entire patient series was considered. In conclusion, the study shows that the predictive value of most of the predischarge variables usually taken into account in the assessment of risk in patients one year after infarction does not extend beyond the first two months.

Predictors of early death after acute myocardial infarction: two months follow-up.

Clinical variables and the results of non-invasive tests (exercise test, echocardiogram, gated equilibrium radionuclide ventriculography and 24 h ECG) were recorded in a series of 202 patients who left the hospital alive after an acute myocardial infarction. The short term (two months) predictive value of all these data was prospectively assessed by uni- and multi-variate analysis. The best correlation with early death was observed with the variables related to the extent of infarction and left ventricular dysfunction, namely: early clinical signs of heart failure, high peak CK-MB level, complete bundle branch block, increased cardiothoracic ratio on chest X-Ray, number of Mets reached during the stress test, echocardiographic dyskinesia index, and decreased left ventricular ejection fraction as measured by radionuclide ventriculography. Using multi-variate stepwise discriminant analysis, the following independent prognostic factors appeared by order of entry: early clinical signs of heart failure, peak CK-MB level and cardiothoracic ratio on chest X-Ray. These results highlight the short-term predictive value of the data related to left ventricular dysfunction and especially of simple clinical data for patients surviving an acute myocardial infarction.