NEUROHORMONAL ACTIVITY AND LEFT-VENTRICULAR GEOMETRY IN PATIENTS WITHESSENTIAL ARTERIAL-HYPERTENSION

The purpose of this study was to investigate whether the basal activit y of the renin-angiotensin-aldosterone system or the basal levels of t he atrial natriuretic peptide (ANP) are related to distinct patterns o f left ventricular (IV) geometry in patients with essential hypertensi on. The left ventricle of patients with arterial hypertension may be e xposed to a variety of growth-regulating mechanisms, including pressur e overload and humoral activation. The interaction of such growth stim uli may be involved in the modulation of LV geometry. LV geometry was determined echocardiographically in 104 patients with mild to moderate essential hypertension. The same number of age-and sex-matched normot ensive subjects served as controls. Plasma renin activity (PRA) and se rum concentrations of aldosterone and ANP were measured by radioimmuno assay. Correlation analyses revealed that PRA was significantly associ ated with septal wall thickness and LV mass index (r = 0.25; p < 0.005 each). In addition, as compared with normal subjects (1.0 +/- 0.7 ng/ ml/hr), PRA was significantly increased in patients with concentric LV hypertrophy (LVH) (3.4 +/- 6.6 ng/ml/hr, p < 0.01). Aldosterone displ ayed a close correlation with septal, posterior, and relative wall thi ckness (r > 0.27, p < 0.005 each). Compared with normal subjects (74 /- 27 pg/ml), patients with hypertension and pathologic patterns of IV geometry were characterized by elevations of aldosterone (LV remodeli ng 203 +/- 93 pg/ml, concentric LVH 123 +/- 67 pg/ml; eccentric LVH 19 9 +/- 89 pg/ml; p < 0.05 each). ANP was significantly associated with septal wall thickness, left ventricular dimension, and LV mass index ( r > 0.22, p < 0.005 each). Furthermore, compared with normal subjects (50 +/- 17 pg/ml), ANP values were significantly increased in patients with hypertension and concentric LVH (80 +/- 44 pg/ml, p < 0.005) and eccentric LVH (88 +/- 24 pg/ml, p < 0.001). Multivariate analysis adj usting for systolic blood pressure, body mass index, and age revealed that renin and ANP were independently associated with LV mass index (p < 0.05 each). interestingly, adjusted PRA levels were not related to any specific pattern of IV geometry. In contrast, adjusted ANP levels were associated with concentric and eccentric LVH, whereas adjusted al dosterone levels were significantly elevated in subjects with LV remod eling and eccentric LVH (p < 0.005). Thus elevated levels of renin and ANP may be found in patients with hypertension and elevated LV mass i ndex. In addition, ANP and aldosterone are related to specific geometr ic patterns of the left ventricle. The data may further stimulate the discussion on the mechanisms that account for alterations of IV geomet ry in hypertension.