Physiologic changes during supraventricular tachycardia and release of atrial natriuretic peptide.

Plasma levels of atrial natriuretic peptide (ANP) increase markedly during supraventricular tachycardia (SVT). Although natriuresis associated with SVT may be secondary to the augmented secretion of ANP, whether or not physiologic changes other than natriuresis can be attributed to the release of ANP has not been determined. In the present study, plasma ANP levels in 10 patients with SVT were found to be significantly (p less than 0.05) increased, from 37 +/- 11 pg/ml (mean +/- standard error of the mean) during the control period to 160 +/- 54 pg/ml at 60 minutes after the induction of SVT. Urinary sodium excretion, although insignificant, tended to increase during the 30-minute period after SVT termination. The filtration fraction determined by the ratio of creatinine to para-aminohippurate clearance significantly increased during SVT. An increase in capillary permeability seemed to have occurred as there was a rise of hematocrit, the changes of which showed a different time course from that of the urine volume. The ratio of plasma aldosterone concentration to plasma renin activity significantly decreased during SVT. As the same effects are observed after ANP infusion, these changes were attributed to ANP activity.