Influence of Hypertension on Early Carotid Artery Remodeling

Abstract

Objectives-We aimed to analyze the influence of hypertension on early large artery remodeling. Methods and Results-Carotid intima-media thickness (IMT) and diameter were measured ultrasonographically in 394 normotensive subjects and 327 untreated and 528 treated hypertensive patients. IMT and diameter were increased in hypertensive groups, treated or untreated, compared with the normotensive group (PϽ0.001). Positive association existed between diameter and IMT in the overall study population (PϽ0.001), and this association interacted with the category of clinical groups (PϽ0.01). Key Words: carotid arteries Ⅲ remodeling Ⅲ hypertension Ⅲ ultrasonics Ⅲ antihypertensive treatment A rterial remodeling is potentially important in atherosclerosis, aiming at counteracting the development of lumen compromise of large artery by mutual adaptation of diameter to wall thickening. 1 At the early stage of atherosclerosis characterized by slightly intrusive or preintrusive wall thickening, the lumen size of the artery remains constant or even increases (compensatory enlargement). 2 Advances in highresolution B-mode ultrasonography offer the possibility of assessing concomitantly intima-media thickness (IMT) and diameter of carotid artery 3 and obtaining in vivo information on the adaptation of IMT to diameter. 4,5 Positive relationships were found between carotid diameter and IMT in populations of healthy subjects, independently of coexisting cardiovascular risk factors. 6 -8 However, these relations have not been examined specifically in patients with hypertension, even though the influence of blood pressure on large artery geometry and structure may change the ability of arteries to remodel their lumen as wall thickness increases. Therefore, the objective of the present study was to assess and compare the adaptation of lumen diameter to IMT in the common carotid artery of 3 groups of untreated and treated hypertensive patients and normotensive subjects. Methods Study SubjectsOne thousand two hundred forty-nine consecutive subjects referred between April 2000 and May 2001 for cardiovascular risk assessment and having undergone appropriate ultrasonographic carotid examination were included in the study. They were divided into 2 groups according to the presence (hypertensive group, nϭ855) or absence (normotensive group, nϭ394) of hypertension defined as blood pressure Ն140 systolic or Ն90 mm Hg diastolic or the current use of antihypertensive treatment. Hypertensive patients were subdivided into 2 groups of untreated (nϭ327) and treated (nϭ528) subjects according to the absence or presence of current antihypertensive treatment for the past 3 months. Among treated hypertensive patients, 314 were treated with a class of drug given alone (monotherapy) or in association with a diuretic (diuretic bitherapy) and subdivided into the following 4 groups according to the class of drug: calcium antagonists, nϭ81; angiotensin converting enzyme inhibitors, nϭ82; ␤ blockers, nϭ93; and angiotensin receptors antagonists, nϭ58. Risk Factors Ev...

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