The long-term hemodynamic effect of fusaric acid in elderly hypertensive patients.

Abstract

The hemodynamic effect of fusaric acid calcium salt (calcium salt of 5-butylpicolinic acid), an inhibitor of dopamine beta-hydroxylase, was studied in long-term administration of this agent in 10 elderly hypertensive patients. The hemodynamic items were measured by dye-dilution method before and 3 months, 6 months and one year after administration of fusaric acid calcium salt. The main hemodynamic changes observed were as follows: 1) Heart rate did not show any consistent change. 2) Systolic, diastolic and mean blood pressure decreased. The mean values of these pressures after fusaric acid calcium salt administration were significantly lower than the mean values before administration of this agent. 3) Total peripheral vascular resistance index decreased. The mean values of this index at 3 months, 6 months and one year after fusic acid calcium salt administration were significantly lower than the mean value before administration of this agent. 4) Cardiac index showed various changes throughout administration of fusaric acid calcium salt. The changes in this index might be secondary following the changes in total peripheral vascular resistance index, an inverse correlation being existed between them. 5) Stroke volume index showed almost a similar pattern of change as observed in cardiac index. An inhibitory action of fusaric acid calcium salt on the inotropism of the heart could be hardly found. 6) Plasma volume showed no tangible changes after fusaric acid calcium salt administration throughout one year. It might be concluded that fusaric acid calcium salt elicited the hypotensive response primarily through the reduction of total peripheral vascular resistance index.