RELATIONSHIP BETWEEN LEFT-VENTRICULAR GEOMETRY AND NATRIURETIC PEPTIDE LEVELS IN ESSENTIAL-HYPERTENSION

Previous studies have shown that plasma levels of atrial natriuretic p eptide (ANP) and brain natriuretic peptide (BNP) are increased in esse ntial hypertension However, whether left ventricular geometry affects plasma ANP and BNP levels remains unknown. To investigate the effect o f left ventricular geometry on plasma ANP and BNP levels in essential hypertension, we measured plasma ANP and BNP levels in 90 patients wit h essential hypertension. All patients were hospitalized. and fasting blood samples were obtained in the early morning after 30 minutes of b ed rest. Plasma ANP and BNP levels were measured by immunoradiometric assay. Hypertensive patients were classified into four groups accordin g to echocardiographic findings that showed normal geometry, concentri c remodeling, eccentric hypertrophy, or concentric hypertrophy. Mean p lasma ANP and BNP levels in all essential hypertensive patients were h igher than those in age-matched normotensive control subjects. Plasma ANP levels in hypertensive patients with concentric remodeling, eccent ric hypertrophy, and concentric hypertrophy were higher than in normot ensive control subjects, although there were no differences between no rmotensive subjects and hypertensive patients with normal geometry. Pl asma BNP levels tended to be higher in hypertensive patients with norm al geometry, concentric remodeling, and eccentric hypertrophy than in normotensive control subjects; however, the differences were not signi ficant. Plasma BNP levels acid BNP/ANP ratio were specifically higher in concentric hypertrophy. There were significant correlations between ANP and left ventricular mass index, relative wall thickness, interve ntricular septal thickness, posterior wall thickness, and mean arteria l pressure. Plasma BNP levels significantly correlated with relative w all thickness, interventricular septal thickness, posterior wall thick ness, and left ventricular mass index but not with mean arterial press ure. In addition, plasma BNP levels were well correlated with ANP leve ls, and the slope for the linear regression model was steeper in conce ntric hypertrophy than in the other four groups. These results show th at plasma ANP and BNP levels are increased in essential hypertensive p atients with left ventricular hypertrophy. Furthermore, BNP secretion is augmented to a greater extent in concentric hypertrophy. Thus, meas urement of plasma ANP and BNP levels may be useful for the detection o f concentric left ventricular hypertrophy in patients with essential h ypertension.