Opposite associations of circulating aldosterone and atrial natriuretic peptide with left ventricular diastolic function in essential hypertension

It has been shown in animal experiments that angiotensin II and aldosterone have mitogenic effects on the cardiovascular system, whereas atrial natriuretic peptide has antimitogenic properties. The aim of the present study was to relate plasma renin activity, angiotensin II, aldosterone and atrial natriuretic peptide to left ventricular structure and function, assessed by use of imaging echocardiography and transmitral Doppler velocimetry in 73 patients with essential hypertension, World Health Organization stages I-II, aged 43 +/- 10(s.d.) years. Left ventricular mass, wall thickness and internal diameter were not independently related to the biochemical variables, except for a weak and positive association of wall thickness with plasma aldosterone (P = 0.06). However, left ventricular early inflow peak velocity and deceleration were independently and inversely related to age (P < 0.001) and to plasma aldosterone (P < 0.01), and positively to plasma atrial natriuretic peptide (P < 0.05). Peak flow velocity during atrial contraction was positively related to plasma atrial natriuretic peptide both before (P < 0.001) and after (P < 0.05) controlling for significant covariates (age, sex and blood pressure). We conclude that circulating renin, angiotensin II, aldosterone and atrial natriuretic peptide are not independently related to left ventricular mass in essential hypertension. The inverse association of plasma aldosterone with indices of diastolic function is compatible with a stimulating effect of aldosterone on myocardial fibrosis, which is opposed by atrial natriuretic peptide. The apparently conflicting positive association of this peptide with atrial peak velocity is most likely due to stimulation of its secretion by atrial involvement.