Plasma Concentration of Atrial and Brain Natriuretic Peptides in the Patients with Essential Hypertension

ABSTRACT

BACKGROUND: Left ventricular hypertrophy(LVH) is one of the complications of hypertension and has been known as an independent risk factor of cardiovascular complications. Recently, it has been reported that hypertensive patients with LVH had the most advanced extracardiac target-organ damage compared with other groups. Previous reports have shown that mean plasma atrial natriuretic peptide(ANP) and brain natriuretic peptide(BNP) levels in hypertensive patients are higher than in normotensive subjects. Therefore, in this study, we investigated the relationships between the plasma ANP and BNP levels and the degree of LVH in hypertensive patients and in normotensive subjects and also investigated the clinical significance of measurement of plasma ANP and BNP levels. METHODS: In all study subjects, left ventricle mass index(LVMI) and left ventricle geometry were measured by M-mode echocardiography. Measurements were made by the recommendations of the American Society of Echocardiography. Plasma ANP and BNP levels were measured by radioimmunoassay method. RESULTS: 1) 57% of the hypertensive patients had eccentric hypertrophy and 6% had concentric hypertrophy. 2) LV mass and LVMI of normotensive subjects and hypertensive patients were 169+/-53 g, 229+/-64 g and 99+/-27.3 g/m2, 142+/-37.7 g/m2, respectively(P<0.05). 3) There were statistically significant correlations between blood pressure and LVMI in all subjects(r=.43, P<0.05). 4) Plasma ANP levels were significantly increased in hypertensive patients than normotensive subjects (28.2+/-14.3 pg/mL and 42.8+/-26 pg/mL, respectively; P<0.05). 5) Plasma BNP levels were significantly increased in hypertensive patients than normotensive subjects (18.4+/-5.4 pg/mL and 36.5+/-26 pg/mL; respectively, P<0.05). 6) Plasma BNP levels were significantly increased in 63% of the hypertensive patients with LVH(P<0.05). 7) There were statistically significant correlations between blood pressure and plasma ANP and BNP levels(ANPr=.39, p<0.05, BNPr=.31, P<0.05). CONCLUSIONS: Plasma ANP and BNP levels were increased in the hypertensive patients but only plasma BNP levels were significantly increased in the hypertensive patients with LVH. Measurement of plasma BNP levels may be useful for early detection of LVH, an independent risk factor of cardiovascular complications. Therefore intensive blood pressure control in these patients may reduce cardiovascular morbidity and mortality.