Abstract

It is widely known that sudden decreases in atrial pressure inhibit Atrial Natriuretic Peptide (ANP) secretion. The aim of this study is to assess changes in plasma levels of this peptide following catheter balloon valvuloplasty of the mitral valve. Ten patients with severe mitral stenosis are included in the study. Mitral valvuloplasty caused an increase in mitral valve area and a sudden decrease in left atrial presure. The decrease in the right atrial presure was disconcordant and insignificant. Elevated plasma ANP levels before valvuloplasty were decreased significantly after 60 minutes following valvuloplasty. Positive correlations were observed between ANP levels before valvuloplasty and 60 minutes after and with right and left atrial pressures. These findings imply that mitral stenosis which causes an increase in atrial pressure is an important stimulus for the release of ANP in humans. Our results suggest that a decrease in the tension of atrium myocytes leads to a rapid decrease in ANP secretions.