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1 The effects ofintravenous nicardipine (2.5 mg) on the left ventricular (LV) inotropic state, LV metabolism, and coronary haemodynamics were analysed in 22 patients with angina pectoris. 2 Measurements were made at fixed heart rate (atrial pacing), under basal state, and during a cold pressor test. 3 After nicardipine, coronary blood flow and oxygen content in the coronary sinus increased significantly. 4 The indices of inotropic state increased slightly, and the rate of isovolumic LV pressure fall improved. 5 Myocardial oxygen consumption was unchanged despite the significant reduction in pressure-rate product, but LV lactate uptake increased, particularly during the cold pressor test. 6 When nicardipine was administered after propranolol, the indices of inotropic state were unaffected. 7 The lack of direct effect of nicardipine on LV inotropic state was further confirmed by intracoronary injection of 0.1 and 0.2 mg in a separate group of 10 patients. 8 It is concluded that the nicardipine-induced coronary dilatation seems to improve perfusion and aerobic metabolism in areas with chronic ischaemia, resulting in reduced lactate production and augmented oxygen consumption. Keywords angina pectoris coronary vascular resistance inotropic state myocardial metabolism nicardipine vasodilatation

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The purpose of the study was to examine whether the prolonged administration of the beta 1-adrenoceptor partial agonist xamoterol could improve left ventricular diastolic function and affect the global remodeling process of the left ventricle after anterior myocardial infarction. In 22 patients with anterior myocardial infarction and single-vessel disease, left ventricular angiography (+ Millar) was performed under basal conditions 1 to 2 months after the acute myocardial infarction. Eight patients were then treated for 3 months with placebo and 14 were treated with xamoterol (200 mg bid) and a second left ventricular angiographic study was performed. Angiograms were digitized frame by frame to derive the diastolic pressure-volume relationship and to compute wall stress. An index of elastic myocardial stiffness was computed at a constant stress of 30 kdynes/cm2 before and after treatment. To evaluate changes in left ventricular shape, segmental areas in anterior and inferior segments were computed and compared at end-diastole and end-systole. After xamoterol, left ventricular end-diastolic pressure and mean diastolic wall stress decreased (from 24 +/- 5 to 15 +/- 5 mm Hg and from 57 +/- 32 to 38 +/- 22 kdynes/cm2, respectively; both p less than .01 vs baseline and vs placebo). These changes were accompanied by a downward shift in the diastolic pressure-volume relationship and by a decrease in the index of myocardial stiffness from 526 +/- 270 to 371 +/- 194 kdynes/cm2 (p less than .02).(ABSTRACT TRUNCATED AT 250 WORDS)

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