[High-resolution ultrasonographic study of atherosclerotic lesions of the carotid arteries in borderline essential arterial hypertension].

BACKGROUND

High resolution echotomographic study of the carotid arteries allows the examination of the arterial wall and the resulting alterations from different factors. Aim of the present study is to evaluate the atherosclerotic lesions of the extracranial carotid arteries wall in subjects with essential borderline arterial hypertension, pharmacologically untreated. The selection of the patients was made, at first, by means of sphigmomanometric measurement of blood pressure and successively by means of 24-hour blood pressure monitoring.

METHODS

We studied: 59 subjects with borderline essential hypertension with casual systolic arterial pressure between 140 and 160 mm Hg and/or diastolic between 90 and 95 mm Hg and increased ambulatorial pressure; 11 subjects with white coat hypertension with casual systolic pressure between 140 and 160 mm Hg and/or diastolic between 90 and 95 mm Hg with normal ambulatorial pressure; 30 normotensive subjects with casual blood pressure < 140/90 mm Hg and normal ambulatorial pressure. Borderline hypertensive subjects were divided in two groups: Group 1 with sensible fall of blood pressure values, from day to night, more than 10% (14.3% systolic and 14.5% diastolic), and Group 2 with reduced nocturnal blood pressure fall, lesser than 10% (3.8% systolic, 2.7% diastolic). All the patients underwent high-resolution B-mode echotomography of both carotid arteries, which consented the evaluation of the myointimal thickening, of the atherosclerotic plaques with their echogenic characteristics and seat. A thickness > or = 0.95 mm Hg was considered as myointimal thickening, while a thickness > or = 2 mm was considered as plaque.

RESULTS

In 59 borderline hypertensive subjects, compared with normotensive subjects, it was more frequent the detection either of myointimal thickening (p < 0.01) or subjects with plaques (p < 0.05), or subjects with more than one plaque (p < 0.05). In those subjects with white coat hypertension, it was detected a prevalence of myointimal thickening and plaques identical to that of normotensive subjects and lesser compared with borderline hypertensive subjects, not statistically meaningful. In those hypertensive subjects with reduced nocturnal blood pressure fall (Group 2), compared with Group 1, it was significatively more frequent the detection of myointimal thickening (p < 0.01), of subjects with plaques (p < 0.01) and subjects with more than one plaque (p < 0.05). There were no meaningful differences either among hypertensive and normotensive subjects or between those two sub-groups of hypertensive subjects for what concerns seat and echogenic characteristics of the plaques: the more frequent localization was at level of the common carotid artery and bifurcation, and less frequently at level of internal and external carotid artery. More frequently "hard" plaques and less frequently "fibrous", "mixed" and "soft" plaques were found.

CONCLUSIONS

In conclusion, the results of our investigation document the role of the increase of the blood pressure, even of mild entity like in borderline essential hypertension, in determining atherosclerotic lesions of the carotid arterial wall, and the usefulness of both the echotomographic study, that shows such lesions, and of the ambulatory monitoring, that allows a better selection of hypertensive patients, to study and identify hypertensive subjects at minor or major risk.