RESUMO
Conduit artery distensibility affects the pulsatile component of afterload and may contribute to impaired left ventricular function in patients with congestive heart failure (CHF). The objectives of this study were to (1) determine whether arterial distensibility is reduced in patients with CHF, and (2) determine whether decreased arterial compliance is related to an abnormality in vascular wall structure (i.e., wall thickness or excessive levels of circulating neurohumoral vasoconstrictors, or both). The study participants included 40 patients with CHF secondary to idiopathic dilated cardiomyopathy and 33 age-matched healthy volunteers. High-resolution ultrasonography was performed to directly visualize the common carotid artery and measure its diameter and wall thickness. Its elastic properties were determined by relating changes in arterial diameter to changes in pressure generated with each heart beat. Carotid artery distensibility was less (14.1 +/- 1.1 vs 25.3 +/- 1.6 10(-6).N-1.m2, p < 0.001) and Young's modulus of elasticity was greater (3.99 +/- 0.51 vs 2.29 +/- 0.23 10(5).N.m-2, p < 0.005) in patients with CHF than in normal subjects. Also, carotid artery wall thickness was increased in patients with CHF. When the entire population was considered, age, wall thickness, and plasma norepinephrine and aldosterone concentrations correlated inversely with distensibility, whereas age and plasma norepinephrine concentration correlated directly with elasticity. Among normal subjects, only age correlated inversely with distensibility; among patients with CHF, only plasma norepinephrine concentration correlated with elasticity. It is concluded that carotid artery distensibility is reduced in patients with CHF.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Cardiomiopatia Dilatada/complicações , Artéria Carótida Primitiva/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Adulto , Idoso , Aldosterona/sangue , Cardiomiopatia Dilatada/sangue , Artéria Carótida Primitiva/diagnóstico por imagem , Artéria Carótida Primitiva/patologia , Complacência (Medida de Distensibilidade) , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue , Análise de Regressão , UltrassonografiaRESUMO
BACKGROUND AND PURPOSE: This article describes the prevalence of extracranial carotid atherosclerosis assessed by ultrasonography, its association with risk factors, and its relation to symptomatic coronary disease and stroke in men and women aged > or = 65 years. METHODS: Maximum percent stenosis, maximum common carotid artery wall thickness, and maximum internal carotid artery wall thickness were assessed using duplex ultrasound in 5,201 men and women aged > or = 65 years in the Cardiovascular Health Study, a study of the risk factors and natural history of cardiovascular disease in the elderly. Existing coronary disease and stroke were assessed by physical examination and participant history. RESULTS: Detectable carotid stenosis was present in 75% of men and 62% of women, although the prevalence of > or = 50% stenosis was low, 7% in men and 5% in women. Maximum stenosis and maximum wall thickness measurements increased with age and were uniformly greater at all ages in men than in women (p < 0.00001). Established risk factors for atherosclerosis (hypertension, smoking, diabetes) and indications of vascular disease (left ventricular hypertrophy, major electrocardiographic abnormality, bruits, and history of heart disease or stroke) related to all three carotid artery measures in the elderly. Of the three ultrasound measures, the best correlate for a history of coronary disease was maximum internal carotid artery wall thickness. For stroke the best correlate was common carotid artery wall thickness. Multiple logistic regression models of prevalent coronary heart disease and stroke that included the ultrasound findings indicated, after adjustment for age and sex, that maximum internal wall thickness and maximum common carotid wall thickness were significant correlates of both. Maximum stenosis did not add significantly to the correlation. CONCLUSIONS: In the elderly the incidence of carotid atherosclerosis was high, although the frequency of severe disease was low. The prevalence and severity of carotid atherosclerosis continued to increase with age even in the late decades of life, and more disease was found in men than in women at all ages. Known risk factors for atherosclerosis continued to relate to carotid abnormalities in the later decades of life, both in symptomatic and asymptomatic subjects.