[Intravenous trinitroglycerin during acute myocardial infarction with cardiac failure. Cooperative study of 68 patients (author's transl)].

Intravenous trinitroglycerine was administered in 68 patients in cardiac failure during the acute phase of myocardial infarction. With a mean hourly dose of 1.58 mg, trinitroglycerine was effective against signs of left and right heart failure after about ten minutes for almost all the teams involved, its tolerance being excellent. Mean capillary pressure fell by 33% (from 22.4 +/- 0.71 mmHg to 15.5 +/- 0.60 mmHg; n = 68; p < 10(-9), as did mean pulmonary artery pressure. Mean right atrial pressure fell by 25% (from 9.96 +/- 0.53 mmHg to 7.48 +/- 0.58 mmHg; n = 68; p < 10(-9). Cardiac output increased by 10.7% (from 2.48 +/- 0.07 l/mn/m2 to 2.74 l/mn/m2; n = 68; p < 10(-7). Since cardiac output was unaltered, systolic index was improved, as was cardiac index, by 11.5% (from 28.4 +/- 1.08 cm3/syst/m2 to 31.7 +/- 1.15 cm3/syst/cm2; n = 68; p < 10(-5). Mean arterial blood pressure was slightly decreased (-9.3%; p < 10(-9), as were systemic resistance (-13%; p < 10(-6) and pulmonary resistance (-27%; p < 10(-6). Systolic work index was significantly improved by 8.37% (from 31.3 +/- 1.73 g-m/m2 to 33.7 +/- 1.74 g-m/m2); n = 68; p < 0.01), which reflects, in view of the decrease in the total work supplied by the heart, a redistribution in favour of more useful work. Treatment must be adapted for each patient, in order to determine the optimum hourly dose of TNT,. which ensures the best cardiac index whilst adequately reducing capillary pressure to levels of the order of 14 to 18 mmHg. Treatment must be closely observed and altered several times a day in relation to values of cardiac output and pulmonary capillary pressure.