THE ACUTE EFFECTS OF INDUCED TACHYCARDIA ON CORONARY SINUS AND ARTERIAL PLASMA-LEVELS OF ATRIAL-NATRIURETIC-PEPTIDE AND ON ARTERIAL CATECHOLAMINES

Atrial natriuretic peptide (ANP) was measured in coronary sinus (CS) p lasma in seven patients with induced tachycardia. Right atrial pressur e (RAP) and femoral artery (FA) levels of ANP, noradrenaline (NA) and adrenaline (A) were measured before and after 5 min with tachycardia. During tachycardia, ANP in CS plasma increased from 381 +/- 273 (mean SD) to 1376 +/- 1191 pmol l-1 (p < 0.0001), and ANP levels in FA plasm a from 89 +/- 48 to 231 +/- 151 pmol l-1 (p < 0.005). A significant in crease was observed for peak RAP, whereas mean RAP remained unaltered. While no correlation existed between the increase in CS plasma ANP le vel and RAP, significant correlations were found between the changes i n FA plasma ANP and RAP, and between FA plasma levels of ANP and NA. F ollowing tachycardia, significant correlations were found both between ANP in CS and FA plasma and between the changes in these plasma level s. Whereas the changes in FA plasma levels of ANP during tachycardia s eems dependent of RAP and arterial plasma levels of NA, the CS plasma ANP level appears to be independent of the two factors, probably becau se CS plasma ANP are drained mainly from the left side of the heart.