[Clinical and hemodynamic tolerance of intravenous diltiazem in the acute phase of myocardial infarction].

The aim of this paper is to study the clinical and haemodynamic tolerance of intravenous diltiazem in a bolus dose of 10 mg followed by an infusion of 360 mg over 24 hours in 12 patients in the acute phase of myocardial infarction. We did not observe any significant modification in the heart rate or in the pulmonary artery diastolic pressure. The mean blood pressure decreased from 111.5 +/- 11.8 mmHg to 92.8 +/- 12.7 mmHg (p less than 0.001) after a 24 infusion. The cardiac index increased from 2.34 +/- 0.62 1 X min1 X m-2 to 3.05 +/- 0.95 1 X min-1 X m-2 (p less than 0.05) and the systemic vascular resistance decreased from 2 150 +/- 640 dyn. s.cm-5 to 1 403 +/- 308 dyn.s.cm-5 (p +/- 0.005). Three patients presented a rise in the pulmonary artery diastolic pressure of more than 30 mmHg and in one of these patients, the diltiazem had to be stopped. These three patients all had a high initial pulmonary capillary pressure (greater than 18 mmHg). The drug was well tolerated clinically. On electrocardiography, four patients presented conduction disorders, all of which regressed when the diltiazem was stopped (a 3rd degree atrioventricular block with narrow QRS complexes, a Luciani-Wenckebach type of 2nd degree atrioventricular block and two cases of 1st degree atrioventricular block. Overall, intravenous diltiazem was well tolerated in terms of clinical and haemodynamic parameters in these patients in the acute phase of a myocardial infarction, provided the left ventricular filling pressure was not excessively elevated.(ABSTRACT TRUNCATED AT 250 WORDS)