Análise da correlação do espessamento médio-intimal proximal e distal nas carótidas comuns

• Autor(a) principal: Roelke, Leonard Hermann
• Data de Publicação: 2011
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/7962
• topic: Intima-media thickness; Carotid arteries; Atherosclerosis; Cardiovascular risk; Espessamento médio-intimal; Carótidas; IMT; Aterosclerose; Risco cardiovascular.; RCU; Ultrassom; Prática clínica; Fisiologia; 61

Background. The intima-media thickness (IMT) of the carotid arteries has been widely used as a noninvasive method to assess the cardiovascular risk because of its association with ischemic cardiovascular events. In the clinic practice, the IMT has been used as atherosclerosis predictor and as an additional tool to assess the cardiovascular risk according to the Framingham score. The high resolution ultrasound is used to measure carotid IMT in view of superficial localization of the artery and low cost of the exam. Different regions of carotid arteries, however, have been used to assess IMT, going from the common to the internal carotid artery, carotid bulb, either bilaterally or unilaterally. Aims: To correlate the thickening of the media-intima complex in different regions of the common carotid arteries in order to orientate the use of this index in daily clinical practice. Methods: IMT values were measured in the proximal and distal region of both common carotid arteries of 789 participants (both sexes, age 35-74 years) that attended to the Investigation Center of the ELSA study in Espírito Santo State. Images were obtained in the supine position with a Toshiba Aplio (model SSA-790A, version XG) ultrassonography platform by using a large band linear transducer with central frequency of 7.5 MHz (5.0-11.0 MHz). IMT was measured by using the dedicated software of the same equipment. Data were considered as following a normal distribution e the Pearson’s correlation coefficient ( r ) was used to determine the association between the IMT recorded at different sites of right and left common carotid arteries. The analysis were initially performed by the all group and then for the sub-groups without (<0.90 mm, 49% of the sample) a with (≥0.90 mm) subintimal thickening at least at one measured site. Statistical significance of associations was set at p<0.05. Results: A progressive increase in IMT was observed with age in all measured sites in the whole group and associations ranged from 0.56 to 0.69. An important decrease of association ( r ranging from 0.20 to 0.40) was observed in the group IMT≥0.90 mm suggesting low reproducibility of IMT when the thickness of the media-intima complex is increased. Conclusion: Despite the recent recommendations to measure the intima thickening in the distal region of the carotid artery, our data suggest that this recommendation should be restricted to epidemiological studies. The low correlations observed in the ≥0.90 mm group indicate that sub-intimal thickening is a focal process. Therefore, in the clinical practice, the whole extension of both common carotid arteries should be investigated to determine presence of IMT increase