Abstract
We measured the peripheral venous pressure (VP) in supine leg exercise in 25 "normal" subjects and 122 patients with primarily left-sided heart diseases (NYHA class I = 68, class II = 54 cases) to determine whether or not plasma catecholamine concentration would increase in patients with mild congestive heart failure, in response to dynamic exercise. Cardiac patients (n = 122) were divided into 2 groups on the basis of VP increment (delta VP): Group N had 60 patients with delta VP less than 35 mmH2O, and Group H had 62 patients with delta VP in excess of 35 mmH2O. Plasma concentrations of noradrenaline (NA) and adrenaline (A) were measured before and during leg exercise. The relation between delta VP, NA and A, and the relation between delta VP and increments of NA (delta NA) and of A (delta A) by leg exercise were studied in both the cardiac patients and the "normal" subjects (Group C). (1) NA at rest was 0.225 +/- 0.016 ng/ml (mean +/- SE) in Group C and 0.216 +/- 0.009 ng/ml in Group N. It was 0.468 +/- 0.026 ng/ml in Group H, which was significantly higher than in Group C (p less than 0.001), or Group N (p less than 0.001). (2) delta NA was 0.051 +/- 0.009 ng/ml (mean +/- SE) in Group C, 0.067 +/- 0.007 ng/ml in Group N, and 0.249 +/- 0.019 ng/ml in Group H. There was a statistically significant difference in delta NA between Groups C and H (p less than 0.001) and between Groups N and H (p less than 0.001). (3) There was no significant difference between the three groups in A at rest, or in delta A. (4) There was a correlation between delta VP and NA at rest (r = 0.614, p less than 0.001) and between delta VP and delta NA (r = 0.708, p less than 0.001). These data suggest that sympathetic nervous activity increased in the patients with high delta VP but without overt heart failure, and that the constriction of the capacitance vessels caused by an increase in NA could be at least one of the mechanisms involved in raising the delta VP in those patients.
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