RENAL URODILATIN SECRETION IS ASSOCIATED WITH DIURESIS AND NATRIURESIS AFTER SPONTANEOUS SUPRAVENTRICULAR TACHYCARDIA

Patients with paroxysmal supraventricular tachycardia (SVT) may have a polyuria after termination of tachycardia. There is increasing eviden ce that the renal peptide urodilatin (ANP (95-126)) - and not plasma A NP (ANP (99-126)) - is the member of the natriuretic peptide family me diating natriuresis and diuresis in man. In patients with SVT we, ther efore, analyzed the relationship between diuresis, natriuresis, plasma ANP, urinary urodilatin excretion and renal excretion of cyclic GMP, the second messenger in the ANP system. During and after clinical pres entation with spontaneously occurring SVT, two patients with AV-nodal and one patient with atrioventricular reentry tachycardia (heart rate 160 to 200 bpm) were studied. Urinary urodilatin excretion was correla ted to diuresis (r = 0.73) and natriuresis (r = 0.93); similarily urin ary cyclic GMP excretion was related to diuresis (r = 0.80) and natriu resis (r = 0.87; p < 0.001, respectively). In contrast, there was no s ignificant correlation between plasma ANP concentrations and diuresis (r = 0.28, n. s.) or natriuresis (r = O.11, n. s.). As an explorative analysis, stepwise multiple linear regression identified urinary urodi latin as the most important contributor to diuresis and natriuresis af ter SVT. These data on polyuria after spontaneous SVT further support the view that in man urodilatin is the member of the natriuretic pepti de family participating in kidney physiology.