Hemodynamic mechanisms of the effect of nitroglycerin in patients with acute myocardial infarction.

We studied the hemodynamic response to intravenous nitroglycerin (NTG) in 40 patients with and without acute heart failure (hemodynamic subsets I-IV) during acute myocardial infarction. Hemodynamic measurements were performed by right heart catheterization. The results showed that NTG response influenced mainly the preload and to a lesser extent the afterload, however these changes were dependent on initial hemodynamic status. The changes in mean arterial pressure and cardiac index were predominantly related to pretreatment pulmonary wedge pressure and slightly to systemic vascular resistance. Response to NTG could be predicted with 85% probability as a decrease of pulmonary wedge pressure, with 58% probability as a decrease in mean arterial pressure and cardiac index, and with 32% probability as an increase in cardiac index and a decrease in systemic vascular resistance. These results indicate that NTG therapy could have optimal results in patients with elevated pulmonary wedge pressure and normal cardiac index, while in the subsets with low mean arterial pressure or low cardiac index potentially deleterious decrease in these values could occur. Therefore the optimal condition for use of intravenous nitroglycerin in the patients with acute heart failure is isolated pulmonary congestion.

Intravenous isosorbide-5-mononitrate in the treatment of acute myocardial infarction.

The action of isorsorbide-5-mononitrate (IS-5-MN) infusion (range 6.0 to 10.0 mg/hour) was studied in 24 patients with and without acute heart failure (hemodynamic subsets I to IV) during acute myocardial infarction. Hemodynamic measurements were performed by right-sided cardiac catheterization. Intravenous IS-5-MN demonstrated significant hemodynamic effects compared with baseline values. In subsets I and II, a decrease in pulmonary wedge pressure (PWP) and in cardiac index (CI), without significant changes in heart rate, mean arterial pressure or systemic vascular resistance index were demonstrated. In subsets III and IV, a major increase in CI and a decrease in systemic vascular resistance index, as well as a decrease in PWP were found. Again no changes occurred in mean arterial pressure and heart rate. The dosage was similar in subsets I to IV (8.0, 7.9, 7.8 and 7.3 mg/hour); thus, the differences in the responses could not be attributed to dosage. It appears that several different patterns of hemodynamic IS-5-MN action exist, assuming that IS-5-MN operates on preload and afterload levels. The action of IS-5-MN mechanisms seems to be dependent on an initial hemodynamic subset. No patient had any deleterious hemodynamic effects. A decrease in CI in subsets I and II was not of clinical importance with these dosages. No nitrate tolerance during 9.0 hours of continuous therapy appeared.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute and chronic efficacy of 10 mg of nitroglycerin patch in stable angina pectoris.

In a single-blind placebo-controlled study, acute and chronic efficacy and duration of action over 24 hours with a 10-mg nitroglycerin (NTG) patch was studied in 24 patients with stable angina pectoris. NTG patch effects were evaluated by means of a multistage treadmill exercise test. During the acute study, exercise tests were performed after the washout period, after placebo patch (5 hours postdosing) and NTG patch (5, 16, 20 and 24 hours postdosing); a 3-day washout period preceded each test. After 3 months of therapy with the NTG patch, exercise tests were performed in 3-day intervals of continuous therapy 5, 16, 20 and 24 hours after patch application. Then, after 7 days of placebo patch therapy, 1 exercise test was performed 5 hours after application. Statistics were obtained by multivariate analysis of difference. Placebo acute and chronic tests did not show any significant difference when compared. Acute and chronic NTG patch tests, (5 to 24 hours) showed significant improvement of maximal exercise time, the time to onset of 1.0 mm ST-depression and to onset of angina as well as maximal ST depression and ST depression 3 and 6 minutes after exercise testing compared with placebo. These effects were significant over 24 hours after acute or continuous therapy, although all values started to decrease after 16 hours, with a decrease of 10% during the acute and of 15% during the chronic period, compared with values at 5 hours. The efficacy was maintained during 3 months of chronic therapy, even with slightly greater magnitude compared with acute administration, mainly during the time of the first angina and 1.0 mm of ST depression.(ABSTRACT TRUNCATED AT 250 WORDS)

[Distribution of prosthetic appliances in young persons]. / Distribucija protetskih radova u mladih osoba.

In fixed prosthodontics, analysis of the distribution of basic prosthetic appliances according to sex, dental arch and particular types of teeth, is quite understandably needed. Therefore, these relations were analyzed in a sample of young adults. The aim was to find out the trends prevailing in our population, that may have proved useful in choosing appropriate measures in prosthetic therapy. Aimed clinical studies were conducted in 5665 students, 3078 females and 2587 males aged 18-20 years. The results obtained pointed to a significant difference in the prosthetic appliances between the upper and lower jaws (89.36% and 10.64%, respectively). Of the total of 1306 appliances in both jaws, 994 (76%) referred to anterior teeth, including first premolars, indicating the prevalence of esthetic requests and indications as compared to the functional ones. According to age, 57% of the total number of prosthetic appliances were made for females and 43% males.

Acute and chronic efficacy of low-dose nitroglycerin patches in stable angina pectoris.

In a single-blind placebo controlled study, acute and chronic efficacy of low-dose nitroglycerin patches (NTG 5 mg/day) was studied in 24 patients with stable angina pectoris. NTG patch effects were evaluated by means of the multistage treadmill exercise test. During the acute study one exercise test was carried out after the wash-out period, after placebo patch (5 hours after application) and NTG patch (5, 16, 20 and 24 hours after application), so that a 3 day wash-out period had preceded each exercise test. Afterwards, chronic NTG patch therapy was continued for three months. At the end of this period exercise tests were carried out, in three day intervals of therapy, 5, 16, 20 and 24 hours after therapy. Then, a 7 day placebo patch period was continued with one exercise test at the end, 5 hours after application. Statistical analysis was carried out by multivariate analysis of difference. Systolic and diastolic blood pressure at rest fell significantly only in the acute 5 hour measurement, with no change in the other periods. The NTG patch augmented significantly mainly all heart rate values during exercise test, with no change in resting values. Placebo, acute and chronic exercise tests did not show any significant difference. They showed a slight but significant placebo influence on the exercise test compared to the wash-out period, improving maximum walking time and time to the onset of angina pectoris but with worsening of maximum ST-depression.(ABSTRACT TRUNCATED AT 250 WORDS)

[Hemodynamic effects of intravenous isosorbide dinitrate in acute myocardial infarct]. / Effets hémodynamiques du dinitrate d'isosorbide intraveineux dans l'infarctus myocardique aigu.

The hemodynamic effects of intravenous isosorbiddinitrate (ISDN) were studied in 15 patients with acute myocardial infarction. Pressure and flow parameters were measured by right heart and radial catheterization and by the thermodilution method. 3-9 mg/hour ISDN was infused intravenously and the hemodynamic values were measured during half an hour in clinically stable state. The statistical analysis was carried out by paired Student's t-test and factors analysis. After ISDN therapy 10 patients showed a significant fall in pulmonary capillary pressure (-24%), 9 a rise in stroke volume index (+21%) and cardiac index (+13%). Two patients only exhibited a rise in pulmonary capillary pressure (+10%) and one a fall in cardiac index (-5%). ISDN changes in pulmonary capillary pressure, stroke volume and cardiac output were mainly due to changes in pulmonary and systemic vascular resistances and much less to those in the systemic venous bed. It can be supposed that intravenous ISDN behaves more like a mixed than a venous vasodilator and can be recommended for acute myocardial infarction patients with high pulmonary capillary pressure and low cardiac output.