Abstract
Hemodynamic responses to administration of metaproterenol and deslanoside were studied in 5 and 3 patients with aortic regurgitation, respectively. Metaproterenol produced an increase in forward stroke volume and aortic flow and a reduction in aortic regurgitant flow. In pure aortic regurgitation, these effects were related to a decreased left ventricular work. Deslanoside uniformly increased stroke volume, forward and regurgitant flows. Left ventricular work also increased after deslanoside administration. Calculated regurgitant valve orifice was changeable in association with alteration of inotropy and heart rate following administration of these drugs. The change of regurgitant flow was positively correlated with the change of regurgitant orifice area (r=0.988) and diastolic time (r=0.696). There was no close correlation between the regurgitant flow and systemic vascular resistance or diastolic pressure gradient from the aorta to left ventricle. It was concluded that when the hemodynamics in aortic insufficiency were altered by drug administration, the size of regurgitant orifice area and the duration of diastole were the important determinant of aortic regurgitation.
