http://repub.eur.nl/res/aut/5486/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/4158/ 1985-01-01T00:00:00Z The hemodynamic effects of diltiazem were investigated in 15 patients with suspected coronary artery disease undergoing routine cardiac catheterization. Diltiazem was given in a high dose of 500 micrograms/kg over a period of 5 min and measurements made before and after drug administration during spontaneous heart rate and during matched atrial pacing. Spontaneous heart rate did not change (-5%; NS). Left ventricular (LV) systolic pressure decreased 24% (p less than 10(-6)) and LV end-diastolic pressure (LVEDP) did not change (-5%; NS). During coronary blood flow measurement, mean aortic pressure decreased 30% (p less than 10(-6)) as global (coronary sinus) and regional (great cardiac vein) coronary vascular resistance diminished with no change in coronary blood flow. Myocardial oxygen consumption decreased 19% (p less than 0.02). During matched pacing, although no change occurred in calculated systolic isovolumic indexes of contractility, end-systolic pressure-volume index decreased 15% (p less than 0.05). The time constant of isovolumic relaxation assessed by a biexponential model decreased. No net change occurred in either global or regional wall motion. In summary, high-dose diltiazem was administered safely to patients with coronary artery disease. It is concluded that, at this dose, diltiazem acted as a peripheral and coronary vasodilator. Hemodynamic changes consistent with a direct negative inotropic and chronotropic effect of the drug were observed. Myocardial oxygen consumption decreased with no change in coronary blood flow. http://repub.eur.nl/res/pub/4159/ 1985-01-01T00:00:00Z The effect of myocardial reperfusion on regional left ventricular function has been quantitated by analysis of segmental wall motion in 185 patients enrolled in a randomized trial comparing thrombolysis with conventional treatment in patients with acute myocardial infarction. When analyzing the hemodynamic data on an "intention to treat" basis we found a significant preservation of left ventricular function after thrombolytic therapy when compared to conventional treatment. In addition, the wall motion analysis showed that a significant improvement of regional function in the "infarct zone" was observed in inferior infarction as well as in anterior infarction, although significant changes in regional function of the remote "non infarct zone" were observed at the acute as well as at the chronic stage. However, our follow-up data indicate that as yet it has not been resolved whether this method of treatment does indeed improve prognosis in patients with acute myocardial infarction. Accordingly, we maintain the view that such invasive treatment should not be generally applied until more follow-up data become available from larger randomized trials. http://repub.eur.nl/res/pub/4172/ 1985-01-01T00:00:00Z The hemodynamic effects of nisoldipine and diltiazem were investigated in two groups of patients undergoing investigation for suspected coronary artery disease. Emphasis was placed on the coronary hemodynamic changes. Approximately equihypotensive doses of these two calcium channel blockers, nisoldipine (6 micrograms/kg) and diltiazem (500 micrograms/kg) were given intravenously. Although both drugs decreased peak systolic pressure by 28% and 24%, respectively, heart rate increased with nisoldipine (68 +/- 9 to 82 +/- 12 bpm) and remained unchanged with diltiazem (70 +/- 9 to 67 +/- 10 bpm). Nisoldipine increased mean coronary sinus blood flow from 146 +/- 40 to 176 +/- 35 ml/min and great cardiac vein flow from 87 +/- 20 to 109 +/- 24 ml/min, producing a significant reduction in the calculated global (from 0.79 +/- 0.2 to 0.43 +/- 0.12 mmHg min/ml) and regional (from 1.43 +/- 0.2 to 0.70 +/- 0.13 mmHg min/ml) coronary vascular resistances. There were no significant flow changes when corrected for heart rate. Global and regional myocardial oxygen consumptions were not significantly altered. Diltiazem had no significant effects on heart rate or global and regional blood flows, although the vascular resistances decreased by 32% and 35%, respectively. Diltiazem reduced global and regional arterio-coronary sinus oxygen differences, resulting in significant decreases in global (from 14.9 +/- 4.7 to 12.1 +/- 2.3 ml/min) and regional (from 5.6 +/- 0.9 to 5.2 +/- 1.2 ml/min) myocardial oxygen consumptions. The major difference between the drugs was in heart rate, despite the similar reductions in aortic pressure. The lack of a positive chronotropic response after diltiazem may explain the reduction in myocardial oxygen consumption. http://repub.eur.nl/res/pub/4175/ 1985-01-01T00:00:00Z The hemodynamic effects of nisoldipine were investigated in 16 patients with suspected coronary artery disease who underwent routine cardiac catheterization. Nisoldipine was given intravenously in a dose of 6 micrograms/kg over 3 minutes and measurements made before and after drug administration during spontaneous and matched atrial paced heart rate. During sinus rhythm, nisoldipine produced a significant increase in heart rate (19%, p less than 10(-5]. Left ventricular systolic pressure decreased 28% (p less than 10(-6) and left ventricular end-diastolic pressure did not change significantly (5%, difference not significant). Coronary sinus and great cardiac vein blood flow increased by 21% (p less than 0.02) and 25% (p less than 0.005), respectively, after nisoldipine administration. Simultaneously, mean aortic pressure decreased 33% (p less than 10(-6]; consequently, the global and regional coronary vascular resistances decreased by 50% (p less than 10(-4]. The decreases in global (-8%) and regional (-4%) myocardial oxygen consumption did not reach statistical significance. A 6% (not significant) increase in end-diastolic volume and an 11% (p less than 0.002) decrease in end-systolic volume resulted in an increase of 21% in stroke volume (p less than 10(-4] with a consistent increase in ejection fraction (+16%, p less than 10(-5]. Total systemic vascular resistance was reduced by 30% (p less than 0.0002). During spontaneous heart rate and matched atrial pacing, the time constant of isovolumic relaxation as assessed by a biexponential model, was significantly shortened.(ABSTRACT TRUNCATED AT 250 WORDS)