RESUMO
OBJECTIVE: Leptin is an adipokine, known to be associated with oxidative stress, inflammation, and atherogenesis. Leptin plays an essential role in atheromatosis-associated inflammatory cascade through stimulation of inflammatory mediators such as soluble intracellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1). However, little is known about this association in patients with atherosclerosis and severe internal carotid artery (ICA) stenosis undergoing carotid endarterectomy (CEA). Our objective was to evaluate the variations of serum leptin levels, as well as sICAM-1 and sVCAM-1 levels in these patients during the process of CEA and 24 hours postoperatively. PATIENTS AND METHODS: The study group enrolled 50 patients undergoing CEA for ICA stenosis (> 70%). Serum leptin, sICAM-1 and sVCAM-1 plasma concentration measurements were performed at 4 distinct time points: before clamping of the ICA, 30 minutes after clamping of the ICA, 60 minutes after declamping of ICA and 24 hours postoperatively. RESULTS: Leptin was significantly decreased during CEA, but an overshooting in its levels was observed at 24 hours after the operation. Both sICAM-1 and sVCAM-1 initially followed the pattern of leptin changes but after completing CEA and up to 24 hours postoperatively a steep increase in their levels was not established. sVCAM-1 and sICAM-1 correlated with indices of oxidative stress at peak inflammatory burden. CONCLUSIONS: Leptin is a circulating marker of carotid atherosclerosis. Oxidative stress and expression of sVCAM-1 and sICAM-1 on vascular endothelial cells are key features in the pathophysiological process of atherosclerosis.
Assuntos
Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/métodos , Molécula 1 de Adesão Intercelular/sangue , Leptina/sangue , Molécula 1 de Adesão de Célula Vascular/sangue , Idoso , Estenose das Carótidas/sangue , Estudos de Casos e Controles , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Estudos ProspectivosRESUMO
Cerebrovascular reserve capacity (CVRC) is a hemodynamic parameter indicating the brain's capacity to overcome ischemia. Transcranial Doppler (TCD) is a useful device to measure CVRC, with high availability and low cost. The aim of the study is to investigate asymptomatic patients with affected CVRC, who could benefit from CEA. One hundred and forty five consecutive patients (60 symptomatic and 65 asymptomatic), with internal carotid artery (ICA) stenosis >70 % and 20 healthy individuals without internal carotid stenosis underwent TCD-inhalation CO(2) tests in order to measure the CVRC in both hemispheres of each patient. CVRC between asymptomatic and symptomatic patients were significantly different in the 95 % confidence interval (CI) as well as the mean CVRC value in contralateral carotid artery. The correlation between CVRC in the carotid artery with stenosis and the existence of symptoms is significant at the 0.01 level. Additionally, symptoms and CVRC of the contralateral carotid artery are also significant at the 0.05 level and CVRC values in asymptomatic patients and the control group at the 0.01 level. None of the covariant factors, except the age, are significantly correlated with CRVC. CVRC could be an early mark-index to evaluate the risk of stroke in this group of patients and to design their therapeutic approach.
Assuntos
Estenose das Carótidas/diagnóstico por imagem , Circulação Cerebrovascular , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Dióxido de Carbono , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/fisiopatologia , Artéria Carótida Interna/cirurgia , Estenose das Carótidas/fisiopatologia , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas , Feminino , Lateralidade Funcional , Humanos , Masculino , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Ultrassonografia Doppler TranscranianaRESUMO
AIM: Homocysteine (Hcy) has been identified as a potential risk factor for vascular disease. This study investigates the role of serum Hcy as clinical risk factor for restenosis after carotid endarterectomy (CEA). METHODS: In a prospective design, we studied patients who underwent carotid endarterectomy with venous patch closure technique with respect to alterations of Hcy levels pre and postoperatively. The patients studied were subjected to reevaluation for possible restenosis at time-points 3, 6, 9, 12, 18 and 24 months postoperatively. RESULTS: Fifty-three symptomatic and 37 asymptomatic patients with stenosis of internal carotid artery >70% were studied. Restenosis appeared in 7.25% of the patients within 24 months postoperatively. Hcy was the only parameter that correlated significantly with the presence of restenosis (P=0.010) and the presence of type VI (complicated) atheromatous plaque (P=0.005) within 24 months postoperatively. CONCLUSION: Hcy levels were found to be statistically significantly correlated with both the presence of complicated atheromatous plaque and the degree of internal carotid artery restenosis after CEA.