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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Fatores de risco para acidente vascular cerebral no pós-operatório de cirurgia de revascularização do miocárdio

Faccini, Felipe Puricelli January 2007 (has links)
Introdução: A indicação de endarterectomia carotídea (EAC) profilática em conjunto com revascularização miocárdica (CRM) permanece assunto indefinido. A cirurgia conjunta é amplamente difundida, mas seus resultados vêm sendo questionados. Método: Coorte retrospectiva de 691 pacientes submetidos à CRM, escolhidos aleatoriamente. Avaliação realizada para dados gerais, presença de lesão carotídea, ateromatose aórtica, desfechos neurológicos e óbito. Resultados: Dentre 691 pacientes submetidos à CRM, 16 pacientes apresentaram acidentes vasculares cerebrais (AVC). Dentre esses, 11 pacientes (68.75%) apresentaram AVC localizados em áreas não compatíveis com as lesões carotídeas, sendo três deles com lesões calcificadas na aorta ascendente. Os pacientes com estenose carotídea apresentaram taxa similar de eventos neurológicos totais, AVC e óbito, comparados com pacientes sem estenose carotídea. Um subgrupo de 35 pacientes com estenose carotídea foi submetido à cirurgia coronariana com (14 pacientes) ou sem (21 pacientes) cirurgia de carótida, obtendo-se taxa de eventos neurológicos totais, AVC e óbito estatisticamente semelhantes. Os pacientes com calcificações aórticas apresentaram risco maior de eventos neurológicos (14,58% versus 6.55%, p=0.011), AVC (3,12% versus 2,18%, p=0,47) e óbito (8,33% versus 4,37%, p=0.12). Discussão: Os eventos neurológicos após CRM correlacionam-se com ateromatose aórtica. Os AVC freqüentemente não têm relação linear com a estenose carotídea. Estratégias para minimizar embolia da aorta podem diminuir as taxas de intercorrências neurológicas. / Introduction: The management of patients with simultaneous disease of carotid and coronary arteries is controversial. Studies showed that aortic calcifications might play a role in postoperative stroke at coronary artery bypass graft (CABG), carotid lesions may not be as important as previously considered. Method: A retrospective cohort of a randomly selected group (including elective and emergency operations) of 691 patients submitted to CABG was reviewed for general data, neurological complications and mortality. Results: Among 691 CABGs 16 patients had postoperative stroke. Among these, 11 patients (68.75%) had strokes not matching carotid lesions and anatomic presentation, three of those had detectable aortic calcifications. The patients with critical carotid stenosis had similar rates of neurological events, stroke and death as compared to patients without. The patients with aortic calcifications presented a higher risk of neurological events (14.58% versus 6.55%, p=0.011), stroke (3.12% versus 2.18%, p=0.47) and death (8.33% versus 4.37%, p=0.12). Discussion: The postoperative neurological events after CABG can be related to aortic calcifications. The strokes after coronary bypass may occur independently of the carotid lesions. Strategies to prevent aortic emboli may help preventing many post-operative strokes.
12

Operative Versorgung von Karotisstenosen in Kombination mit herzchirurgischen Eingriffen an der extrakorporalen Zirkulation / Carotid Endarterectomy combined with Heart Surgery using Cardiopulmonary Bypass

Pölert, Nicolas 14 June 2017 (has links)
No description available.
13

Fatores de risco para acidente vascular cerebral no pós-operatório de cirurgia de revascularização do miocárdio

Faccini, Felipe Puricelli January 2007 (has links)
Introdução: A indicação de endarterectomia carotídea (EAC) profilática em conjunto com revascularização miocárdica (CRM) permanece assunto indefinido. A cirurgia conjunta é amplamente difundida, mas seus resultados vêm sendo questionados. Método: Coorte retrospectiva de 691 pacientes submetidos à CRM, escolhidos aleatoriamente. Avaliação realizada para dados gerais, presença de lesão carotídea, ateromatose aórtica, desfechos neurológicos e óbito. Resultados: Dentre 691 pacientes submetidos à CRM, 16 pacientes apresentaram acidentes vasculares cerebrais (AVC). Dentre esses, 11 pacientes (68.75%) apresentaram AVC localizados em áreas não compatíveis com as lesões carotídeas, sendo três deles com lesões calcificadas na aorta ascendente. Os pacientes com estenose carotídea apresentaram taxa similar de eventos neurológicos totais, AVC e óbito, comparados com pacientes sem estenose carotídea. Um subgrupo de 35 pacientes com estenose carotídea foi submetido à cirurgia coronariana com (14 pacientes) ou sem (21 pacientes) cirurgia de carótida, obtendo-se taxa de eventos neurológicos totais, AVC e óbito estatisticamente semelhantes. Os pacientes com calcificações aórticas apresentaram risco maior de eventos neurológicos (14,58% versus 6.55%, p=0.011), AVC (3,12% versus 2,18%, p=0,47) e óbito (8,33% versus 4,37%, p=0.12). Discussão: Os eventos neurológicos após CRM correlacionam-se com ateromatose aórtica. Os AVC freqüentemente não têm relação linear com a estenose carotídea. Estratégias para minimizar embolia da aorta podem diminuir as taxas de intercorrências neurológicas. / Introduction: The management of patients with simultaneous disease of carotid and coronary arteries is controversial. Studies showed that aortic calcifications might play a role in postoperative stroke at coronary artery bypass graft (CABG), carotid lesions may not be as important as previously considered. Method: A retrospective cohort of a randomly selected group (including elective and emergency operations) of 691 patients submitted to CABG was reviewed for general data, neurological complications and mortality. Results: Among 691 CABGs 16 patients had postoperative stroke. Among these, 11 patients (68.75%) had strokes not matching carotid lesions and anatomic presentation, three of those had detectable aortic calcifications. The patients with critical carotid stenosis had similar rates of neurological events, stroke and death as compared to patients without. The patients with aortic calcifications presented a higher risk of neurological events (14.58% versus 6.55%, p=0.011), stroke (3.12% versus 2.18%, p=0.47) and death (8.33% versus 4.37%, p=0.12). Discussion: The postoperative neurological events after CABG can be related to aortic calcifications. The strokes after coronary bypass may occur independently of the carotid lesions. Strategies to prevent aortic emboli may help preventing many post-operative strokes.
14

Avaliação das alterações da substância branca e cinzenta cerebral nos pacientes com doença carotídea assintomática / Evaluation of brain white and gray matter in patients with asymptomatic carotid disease

Avelar, Wagner Mauad, 1976- 21 August 2018 (has links)
Orientador: Fernando Cendes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T23:12:40Z (GMT). No. of bitstreams: 1 Avelar_WagnerMauad_D.pdf: 2966468 bytes, checksum: ae195d956adfc06599ce07aa216dbfcd (MD5) Previous issue date: 2013 / Resumo: A prevalência da estenose carotídea assintomática (>50%) aumenta com a idade, sendo 10% nos homens acima de 80 anos. A conduta, nesses pacientes, quanto ao tratamento clínico ou correção por angioplastia ou endarterectomia ainda gera discussões. Os primeiros estudos com endarterectomia indicavam um benefício em diminuir o risco de evento cerebrovascular em 5 anos. Com a melhora do tratamento clínico, em que o risco absoluto caiu de 2,5 em meados da década de 80 para 1% ano, a correção de tais estenoses se tornou motivo de discórdia, visto que existe um risco de 2,5% para angioplastia e 1,4% para endarterectomia, como mostrado no estudo CREST, publicado em 2010. Portanto, o uso indiscriminado do procedimento não parece justificado nesse grupo de pacientes. Desta forma, o procedimento cirúrgico somente é recomendado em pacientes selecionados com base na idade, fatores de risco, expectativa de vida e risco peri-procedimento. Entretanto, há estudos que evidenciaram declínio cognitivo em pacientes com estenoses assintomáticas >70%, os quais tiveram melhora após a angioplastia, além de casos de distúrbios do movimento, em especial hemicoreia, os quais reverteram após correção da mesma. Nosso trabalho avaliou 25 pacientes com estenose de carótida/oclusão, assintomáticos quanto às possíveis alterações de substância branca e cinzenta. A estenose/oclusão foi definida pela angiotomografia e então todos os pacientes foram submetidos à ressonância magnética de encéfalo e as imagens foram analisadas através do método de morfometria baseada em voxel (VMB) e através de imagens de tensor de difusão (DTI). Para comparação estatística, usamos imagens de 25 indivíduos saudáveis, pareados por idade. Neste estudo, ambas as análises, de VBM e DTI, demonstraram anormalidades significativas da substância branca quando comparado com ao grupo controle. Tais achados foram difusos e simétricos em ambos os hemisférios (ipsilateral e contralateral a estenose). Diferentemente, a análise de VBM da substância cinzenta demonstrou assimetria da atrofia, predominantemente em áreas correspondendo a circulação anterior do hemisfério ipsilateral à estenose. Nossos achados sugerem que as estenoses/oclusões carotídeas assintomáticas estão associadas a alterações (atrofia) da substância cinzenta do hemisfério ipsilateral à estenose. Esse achado está em concordância com os dados prévios da literatura, como a existência de declínio cognitivo e os distúrbios de movimento, uma vez que estabelece uma associação entre estenose carotídea e perda de substância cinzenta, provavelmente secundária à alteração hemodinâmica. É o primeiro trabalho que pode justificar tais achados / Abstract: The prevalence of asymptomatic carotid stenosis (>50%) increases with age, affecting 10% of men 80 years or older. However there is still no consensus whether clinical, angioplasty or endarterectomy is the best therapeutic option. In earlier studies, endarterectomy showed a benefit in reducing the risk of event in 5 years. The advances in medical treatment though, decreased the absolute risk of stroke to 1% per year and surgical treatment was put in check, since both angioplasty and endarterectomy carry a stroke risk of 2,5 and 1,4 % respectively, as shown in the CREST study. Therefore, the indiscriminate use of the procedure does not seem justified in this group of patients and it should only be recommended in selected patients based on age, risk factors, life expectancy and the risks associated with the procedure. However, studies have demonstrated cognitive decline in patients with asymptomatic carotid stenosis >70%, which showed improvement after angioplasty, and case reports described patients with hemichorea contralateral to the stenosis, which reversed after the surgical procedure. We studied the white and grey matter changes in 25 patients with asymptomatic carotid stenosis/occlusion. The stenosis/occlusion was defined by angiography and all patients underwent brain MRI. Images were analyzed by the method of voxel-based morphometry (VBM) and through diffusion tensor images. Our control group involved 25 healthy subjects, matched for sex and age. We found that both DTI and VBM analyze showed significant abnormalities of white matter compared to controls, and these findings were diffuse and symmetrical in both hemispheres (ipsilateral and contralateral stenosis). Unlike DTI, the VBM analysis showed gray matter atrophy predominantly in areas corresponding to the anterior circulation in the hemisphere ipsilateral to the stenosis. Our findings suggest that the stenosis/occlusion is associated with asymptomatic alterations (atrophy) of the gray matter in the hemisphere ipsilateral to the stenosis. This finding is in agreement with previous clinical data in the literature, such as the existence of cognitive decline and movement disorders, since it establishes an association between carotid stenosis and loss of gray mater, probably secondary to hemodynamic changes / Doutorado / Neurociencias / Doutor em Fisiopatologia Medica
15

Screening for asymptomatic carotid atherosclerosis

Högberg, Dominika January 2017 (has links)
Ischemic stroke is the most common cause of handicap in adults and the third most common cause of death in Sweden. Internal carotid artery atherosclerosis is an important cause and accounts for 20% of ischemic strokes. Screening for carotid atherosclerosis has been debated over the past two decades. The aims of this thesis were (I) to study the prevalence of and risk factors associated with carotid artery atherosclerosis among 65 year old men, (II) to evaluate a simplified ultrasound protocol (the grayscale/mosaic method) for the exclusion of significant carotid artery stenosis for screening purpose, (III) to evaluate the required effect of primary preventive therapy in reducing risk of stroke among patients with asymptomatic carotid disease in order for screening to be cost-effective and (IV) to study natural history of carotid atherosclerosis and outcome five years after screening in 65-year old men. The prevalence of atherosclerotic plaques was high (25%), while the prevalence of >50% stenosis was relatively low (2.0%). Smoking, hypertension, diabetes mellitus and coronary artery disease were independent risk factors and individuals with several risk factors had a higher prevalence of stenosis. Most of those at risk were not on any preventive medication. A simplified grayscale/mosaic method was found to have a high negative predictive value for significant carotid stenosis. The minimum stroke risk reduction effect required for preventive intervention to be cost effective was 22%. Carotid atherosclerotic plaque and stenosis 50-79% has a relatively benign development during five years if treated with BMT and risk factor adjustment. Very few progressed to symptomatic disease. More severe stenosis (80-99%) had higher rate of neurological events, and may benefit from additional intervention. In conclusion, prevalence of silent atherosclerotic disease in carotid arteries was common among 65-year-old men. Most of those at risk had no secondary prevention. There is a simple DUS method that could be used for screening purpose. Screening for carotid disease is only cost-effective if the preventive strategy lowers the risk of stroke by 22%. Men with plaques and moderate stenosis have a good prognosis, but among those with severe stenosis there is a need for further intervention. / Screening for asymptomatic carotid atherosclerosis
16

Análise comparativa dos parâmetros adquiridos com o US doppler transcraniano durante a endarterectomia carotídea por semi-eversão e a angioplastia carotídea / A comparative analysis of transcranial doppler parameters acquired during semi-eversion carotid endarterectomy and carotid stenting

Oliveira, Germano da Paz, 1982- 24 August 2018 (has links)
Orientador: Ana Terezinha Guillaumon / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-24T11:44:57Z (GMT). No. of bitstreams: 1 Oliveira_GermanodaPaz_M.pdf: 4750891 bytes, checksum: 517650637fcacb4ffebc12ad859189bb (MD5) Previous issue date: 2014 / Resumo: Objetivos: Analisar a distribuição temporal de sinais de microembolias (SM) ao longo de diferentes estágios da endarterectomia carotídea (EC) e da angioplastia carotídea (AC) e as variáveis associadas com a ocorrência destes sinais, além de avaliar as mudanças na velocidade média aferida na artéria cerebral média (ACM) durante os dois tipos de intervenção. Material e métodos: Trinta e três pacientes com estenose carotídea foram submetidos ou a EC (17) ou a AC (16). Os SM bem como as velocidades médias na ACM foram adquiridas utilizando o US doppler transcraniano (DTC) e esses dados então analisados e associados a diferentes estágios cirúrgicos (pré-proteção, durante a proteção e pós-proteção), tipos de intervenção (EC ou AC) e diferentes variáveis para encontrar potenciais fatores de risco para embolização. Para análise estatística, foram usados os testes de Qui-quadrado, de Fisher e de Mann-Whitney, além de análise por medidas repetidas das variâncias com transformação por postos (ANOVA), seguido de teste de perfil por contrastes e análise de regressão linear múltipla ajustada para o grupo. Resultados: Uma diferença significativa foi encontrada para o número de SM em ambos os grupos. Houve, em média, 89,8 (± 171,4) sinais por procedimento no grupo EC, enquanto a média no grupo AC foi de 597,5 (± 343,3) sinais por procedimento. A média da velocidade média na ACM foi, em ambos os grupos, significantemente menor no estágio durante a proteção. Anestesia local correlacionou-se positivamente (p=0,003) com aumento dos SM, e, associado a isso, o histórico de tabagismo importante (desde que houvesse a cessação do vício há mais de um ano) correlacionou-se negativamente (0,014) com a ocorrência de SM. Conclusão: EC por semi-eversão, à luz do DTC, provocou uma menor incidência de SM por procedimento do que AC com filtro distal, em todos os estágios cirúrgicos. A média da velocidade média na ACM se comportou de maneira similar em ambos os grupos (EC e AC). Anestesia geral e histórico de tabagismo importante (desde que o paciente houvesse cessado por menos um anos antes da intervenção) foram as únicas duas variáveis no estudo que se correlacionaram significativamente (negativamente) com a ocorrência de SM / Abstract: Objectives: To analyze the temporal distribution of microembolic signals throughout the different stages of both the semi-eversion carotid endarterectomy (CEA) and the carotid artery stenting (CAS) procedures and the variables associated with occurrence of them and to evaluate changes in mean blood flow velocity, for both CAS and CEA, within the ipsilateral middle cerebral artery (MCA). Methods: Thirty three patients with carotid stenosis underwent either a CEA (17) or a CAS (16). Microembolic signals, as well as mean blood flow velocity, were acquired using a Transcranial Doppler scan (TCD) and these data were then analyzed and associated to different surgical stages (pre-protection, during protection, and post-protection), types of procedure (CAS or CEA) and different variables to find potential risk factors. To statistical analysis, chi-squared test, Fisher test, Mann-Whitney test, repeated measures analysis of variance with rank transformation (ANOVA) followed by contrast test and multiple linear regression analysis were used. Results: A significant difference was found for the number of microembolic signals in both groups. There were, on average, 89.8 (± 171.4) signals per procedure in the CEA group, while the average in the CAS group was 597.5 (± 343.3) signals per procedure. The average blood flow in the MCA was, in both groups, significantly lower during the stage of protection. Local anesthesia correlated positively (p= .003) with increase in microembolic signals and history of prolonged tobacco use having dropped the addiction for over a year correlated negatively (p= -.014) with the frequency of microembolic signals. Conclusion: Semi-eversion CEA, in light of our TCD findings, evoked a smaller incidence of hyperintense microemboli per procedure than CAS with a distal filter in all the protection stages. The average of the mean blood flow velocity within the MCA has behaved similarly between both groups (CAS and CEA). General anesthesia and the history of tobacco use (as long as the patient had quit for a year or more prior to surgery) were the only two variables in the study that correlated significantly (negatively) with the frequency of microembolic signals / Mestrado / Fisiopatologia Cirúrgica / Mestre em Ciências
17

Design and Performance of a Localized Fiber Optic, Near-Infrared Spectroscopic Prototype Device for the Detection of the Metabolic Status of "Vulnerable Plaque": in-vitro Investigation of Human Carotid Plaque: a Dissertation

Khan, Tania N. 06 January 2003 (has links)
INTRODUCTION: The "vulnerable plaque" is defined as the "precursor lesion" that ultimately ends in acute coronary thrombi (clots) that create a heart attack. Macrophages and inflammatory cells, found preferentially in vulnerable plaque, sustain their activity in the plaque through anaerobic metabolism and lactate production. The ultimate goal is to assess anaerobic metabolism in-vivo by measuring tissue pH and lactate concentration in atherosclerotic plaques using optical spectroscopy. The proposed in-vitro optical probe design, experimental method, and spectroscopic data analysis methodology are established in this research. METHODS: A fiber optic probe was designed and built based on both Monte Carlo simulations and bench testing with the goal to collect light from a small volume of tissue. A simulation of the depth penetration of the proposed probe was performed on normal and atherosclerotic aortic tissue, and the final probe was bench tested using normal aorta. A method was developed to preserve plaque metabolic status of tissue harvested from patients. Human atherosclerotic tissue obtained immediately after carotid endarterectomy was placed in Minimum Essential Medium (MEM) with non-essential amino acids supplement, bubbled with 75%O2/20%N2/5%CO2 at 37°C. Tissue pH, pCO2, pO2 and temperature with (n=7) and without (n=2) the media preparation over time were reviewed to assess plaque viability and maintenance of physiological conditions. Additional plaques placed in media were used for development of chemometric methods to measure pH and lactate. Areas of each plaque were randomly chosen for analysis. Reflectance spectra were collected with a dispersive spectrometer (400-1100 nm) and a Fourier-transform near-infrared spectrometer (1100-2400 nm) using the fiber optic probe. Reference measurements for tissue pH and lactate were made with glass microelectrodes and micro-enzymatic assay, respectively. Partial least-squares (PLS) data analysis was used to develop multivariate calibration models on an initial set of 5-6 plaques relating the optical spectra to the reference tissue pH (n=20) or the lactate concentration (n=21) to assess data quality. The coefficient of multiple determination (R2), the standard error of cross-validation (SECV), and the number of factors were used to assess the model performance. Additional points were collected from ~14 plaques and added to preliminary data. Pre-processing techniques were then used to see if preliminary data results could be improved by reducing different sources of variability with the introduction of more points. RESULTS: Monte Carlo simulations and depth penetration tests with the final probe design showed light is collected from ~1 mm3 volume of tissue using a 50 micron source-receiver separation. Tissue pH, pCO2, pO2 and temperature values demonstrated that the plaques were viable and stable in the media preparation for a maximum of 4 hours. Data from the first six plaques collected for lactate analysis showed that for seventeen points, a six-factor model produced adequate results (R2=0.83 SECV=1.4 micromoles lactate/gram tissue). Data from the first five plaques collected for tissue pH analysis, showed for seventeen different points, a three-factor model produced adequate results (R2=0.75 SECV=0.09 pH units). When additional points were added to either data set, model results were degraded. CONCLUSIONS: The in-vitro optical probe design and experimental procedures was established and the feasibility of the optical method demonstrated with preliminary data. However, with the addition of more data points, different sources of tissue and spectral variability were observed to affect calibration. The gross pathology type and mismatched optical volume to reference measurement volume limited the tissue pH determination. The reference measurement precision, the spatial resolution of the reference lactate measurement, and unmodeled tissue variability (water and proteins) limited the lactate determination. Large variability in all optical measurements was observed. Additional in-vitro data collection would be required such that the variability due to the tissue is reduced and any spectrometer variability adequately compensated to be able to use the optical calibration in-vivo.
18

Calcium-Binding Protein S100A4 Is Upregulated in Carotid Atherosclerotic Plaques and Contributes to Expansive Remodeling / 頚動脈プラークにおいてS100A4発現が亢進し、陽性リモデリングと関連する

Nagata, Manabu 24 November 2022 (has links)
京都大学 / 新制・論文博士 / 博士(医学) / 乙第13515号 / 論医博第2265号 / 新制||医||1061(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 湊谷 謙司, 教授 石見 拓, 教授 江木 盛時 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
19

Korelacija ultrazvučnih karakteristika ateroskleroze karotidnih arterija i prisustva kardiometaboličkih faktora rizika kod bolesnika sa ishemijskim moždanim udarom / The correlation of ultrasound characteristics of carotid atherosclerosis and the presence of cardiometabolic risk factors in the patients with ischemic stroke

Živanović Željko 04 December 2015 (has links)
<p>UVOD: Ateroskleroza je najče&scaron;ća bolest karotidnih arterija i uzrok je oko 20% svih ishemijskih moždanih udara (IMU). Osim stepena stenoze i određene karakteristike karotidnog plaka označavaju povi&scaron;en rizik za IMU. Ultrazvukom je moguće pouzdano evaluirati aterosklerotske promene na karotidnim arterijama. Iako su faktori rizika (FR) za aterosklerozu istovremeno i FR za IMU, prisustvo identičnih FR kod pacijenata sa IMU, ne znači i prisustvo istog stepena ateroskleroze na karotidnim arterijama. CILJ: Utvrđivanje povezanosti pojedinih ultrazvučnih karakteristika karotidne ateroskleroze, sa prisustvom različitih kardiometaboličkih FR i njihovih biomarkera, kod pacijenata sa IMU. MATERIJAL I METODE: U istraživanje je uključeno 120 pacijenata sa nekardioembolijskim IMU u karotidnom slivu koji su podeljeni u dve grupe; 60 sa lakunarnim i 60 sa nelakunarnim infarktom mozga. Svim pacijentima je određivano prisustvo FR, kao &scaron;to su hipertenzija, dijabetes, hiperlipoproteinemija, pu&scaron;enje, gojaznost, metabolički sindrom, hiperhomocisteinemija i inflamacija. Beležene su vrednosti krvnog pritiska, glikemije, glikoliziranog hemoglobina, parametara lipidskog statusa, apolipoproteina (Apo) A-I i B, lipoproteina a, indeksa telesne mase (BMI), homocisteina, C reaktivnog proteina (CRP). Pomoću karotidnog dupleks ultrazvuka određivane su vrednosti intima-medijalnog zadebljanja (IMT), morfologija plaka, povr&scaron;ina plaka, stepen stenoze. Demografske karakteristike, FR i njihovi biomarkeri, te ultrazvučne karakteristike karotidne ateroskleroze, poređene su između dve grupe pacijenata. Kori&scaron;ćeni su hi-kvadrat test i t-test. Korelacije FR i vrednosti njihovih biomarkera sa različitim karakteristikama karotidnog plaka, određivane su upotrebom Pearsonovog koeficijenta korelacije r i Kramerovog V. Upotrebom regresionih analiza ispitivan je prediktivni značaj određenih FR i njihovih biomarkera u pojavi pojedinih karakteristika karotidnog plaka. REZULTATI: Vi&scaron;e pacijenata sa lakunarnim infarktom je imalo hipertenziju (98.3% naspram 85%; p=0.021). Pacijenti sa lakunarnim infarktom imali su veće vrednosti BMI (27.6 kg/m2 naspram 25.9 kg/m2; p=0.029), dok su pacijenti sa nelakunarnim infarktom imali veće vrednosti CRP (16.4 mg/l naspram 6.8 mg/l; p=0.001). Demografske karakteristike, ostali FR i njihovi biomarkeri, kao i vrednosti karotidnog IMT se nisu značajno razlikovali između dve grupe pacijenata. Pacijenti sa nelakunarnim infarktom su imali veći stepen karotidne stenoze (79.7% naspram 33.2%; p=0,0001), kao i če&scaron;će prisustvo heterogenog plaka (73.3% naspram 35%; p&lt;0,001), hipoehogenog plaka (51.7% naspram 16.7%; p&lt;0.001) i neravnog plaka (81.7% naspram 21.7%; p&lt;0,001). Sa vrednostima IMT značajno (p&lt;0.05) su korelirali životna dob pacijenata (r=0.276), dijabetes (Cramerovo V=0.236), metabolički sindrom (Cramerovo V=0.247), HDL holesterol (r=-0.254), LDL/HDL (r=0.306), ApoA-I (r=-0.386) i ApoB/ApoA-I (r=0.359). Sa prisustvom heterogenog plaka su korelirali metabolički sindrom (Cramerovo V=0.246), ApoB (r=0.213), ApoB/ApoA-I (r=0.207) i povi&scaron;en CRP (Cramerovo V=0.266). Sa neravnom povr&scaron;inom plaka značajno je korelirao povi&scaron;en CRP (Cramerovo V=0.283). Sa stepenom stenoze značajno su korelirali BMI (r=-0.180) i povi&scaron;en CRP (Cramerovo V=0.301). Nezavisni prediktori povi&scaron;enih vrednosti IMT bili su starija životna dob pacijenata (&beta;=0.230; p=0.006), ApoA-I (&beta;=-0.244; p=0.008) i ApoB/ApoA-I (&beta;=0.247; p=0.007). Prediktori prisustva heterogenog plaka bili su mu&scaron;ki pol (p=0.011; OR=3.425), ApoB (p=0.007; OR=8.972), BMI (p=0.0001; OR=0.380), metabolički sindrom (p=0.003; OR=4.555) i povi&scaron;en CRP (p=0.018; OR=2.800). Prediktori prisustva hipoehogenog plaka bili su ApoB (p&lt;0.001; OR=29.2), BMI (p=0.02; OR=0.514), metabolički sindrom (p&lt;0.001; OR=9.224) i povi&scaron;en CRP (p=0.046; OR=2.659). Povi&scaron;en CRP bio je jedini prediktor prisustva neravnog plaka (p=0.002; OR=3.203), kao i prisustva većeg stepene karotidne stenoze (&beta;=0.270; p=0.002). ZAKLJUČAK: Iako je karotidna stenoza znatno zastupljenija među pacijenatima sa nelakunarnim nego lakunarnim nekardioembolijskim IMU, prisustvo kardiometaboličkih FR, njihovih biomarkera i vrednosti IMT se bitno ne razlikuje između ove dve grupe pacijenata. Osim stenoze i prisustvo heterogenog, hipoehogenog i neravnog karotidnog plaka nosi povi&scaron;en rizik za IMU. Među FR i njihovim biomarkerima ApoA-I i ApoB su najbolji prediktori karotidne ateroskleroze. Apolipoprotein B i metabolički sindrom su najjače povezani sa prisustvom heterogenog i hipoehogenog plaka. Povi&scaron;en CRP kod pacijenata sa akutnim IMU može biti znak destabilizacije plaka i ukazivati na prisustvo signifikantne karotidne stenoze.</p> / <p>INTRODUCTION: Atherosclerosis is the most common disease of carotid arteries, causing 20% of all ischemic strokes. Besides the degree of stenosis, certain characteristics of carotid plaques indicate an increased risk for stroke. Carotid ultrasound can reliably evaluate atherosclerotic changes in carotid arteries. Although the risk factors for atherosclerosis are the same as the risk factors for stroke, the presence of identical risk factors in patients with stroke does not necessarily mean the presence of the same degree of carotid atherosclerosis. AIM: To determine correlation of certain characteristics of carotid atherosclerosis detected by ultrasound with the presence of various cardiometabolic risk factors in patients with ischemic stroke. METHODS: The study included 120 patients with noncardioembolic ischemic stroke in the anterior circulation, who were divided into two groups; 60 with lacunar and 60 with nonlacunar brain infarction. The presence of cardiometabolic risk factors, such as hypertension, diabetes, hyperlipoproteinemia, smoking, obesity, metabolic syndrome, hyperhomocysteinemia, and inflammation, was evaluated in all patients. Data regarding blood pressure, glycemia, glycated hemoglobin, lipid status parameters, apolipoprotein (ApoAI and ApoB), lipoprotein a, body mass index (BMI), homocysteine, and C-reactive protein (CRP) were collected. Intima-media thickness (IMT), carotid plaque characteristics (morphology, surface) and the degree of stenosis were determined by carotid duplex ultrasound. Demographic characteristics, risk factors, biomarkers, as well as ultrasound characteristics of carotid atherosclerosis, were compared between patients with lacunar and nonlacunar stroke. Two-sample student t-test and &chi;2 test were used for comparisons. In order to assess the correlation of various risk factors and their biomarkers with different characteristics of carotid plaques, we used the Pearson correlation coefficient r and Cramer&#39;s V. Regression analysis was used to evaluate the association of risk factors and their biomarkers with various carotid atherosclerosis characteristics. RESULTS: More patients with lacunar stroke had hypertension (98.3% vs. 85%; p=0.021). Patients with lacunar stroke had higher BMI values (27.6 kg/m2 vs. 25.9 kg/m2; p=0.029), while patients with nonlacunar stroke had higher CRP values (16.4 mg/l vs. 6.8 mg/l; p=0.001). Demographic characteristics, other risk factors and their biomarkers, as well as carotid IMT were not significantly different between the two groups of patients. Patients with nonlacunar stroke had a higher degree of carotid stenosis (79.7% vs. 33.2%; p=0.0001) and a higher prevalence of heterogeneous plaques (73.3% vs. 35%; p&lt;0.001), hypoechogenic plaques (51.7% vs. 16.7%; p&lt;0.001), and plaques with irregular surface (81.7% vs. 21.7%; p&lt;0,001). IMT was significantly (p&lt;0.05) correlated with the age of patients (r=0.276), diabetes (Cramer&rsquo;s V=0.236), metabolic syndrome (Cramer&rsquo;s V=0.247), HDL cholesterol (r=-0.254), LDL/HDL (r=0.306), ApoA-I (r=-0.386) and ApoB/ApoA-I (r=0.359). The presence of a heterogeneous plaque was correlated with metabolic syndrome (Cramer&rsquo;s V=0.246) ApoB (r=0.213), ApoB/ApoA-I (r=0.207) and elevated CRP (Cramer&rsquo;s V=0.266). A plaque with irregular surface was correlated with elevated CRP (Cramer&rsquo;s V=0.283). The degree of carotid stenosis was correlated with BMI (r=-0.180) and elevated CRP (Cramer&rsquo;s V=0.301). The independent predictors of higher values of IMT were older age (&beta;=0.230; p=0.006), ApoA-I (&beta;=-0.244; p=0.008), and ApoB/ApoA-I (&beta;=0.247; p=0.007). The predictors of the presence of a heterogeneous plaque were male gender (p=0.011; OR=3.425), ApoB (p=0.007; OR=8.972), BMI (p=0.0001; OR=0.380), metabolic syndrome (p=0.003; OR=4.555) and elevated CRP (p=0.018; OR=2.800). The predictors of the presence of a hypoechogenic plaque were ApoB (p&lt;0.001; OR=29.2), BMI (p=0.02; OR=0.514), metabolic syndrome (p&lt;0.001; OR=9.224) and elevated CRP (p=0.046; OR=2.659). Elevated CRP was the only independent predictor of a plaque with irregular surface (p=0.002; OR=3.203) and of a higher degree of carotid stenosis (&beta;=0.270; p=0.002). CONCULSIONS: Although carotid stenosis is significantly more pronounced in patients with nonlacunar than those with lacunar noncardioembolic ischemic stroke, cardiometabolic risk factors, their biomarkers and carotid IMT do not differ significantly between the two groups of patients. In addition to stenosis, a presence of heterogeneous, hypoechogenic and irregular-surface carotid plaques indicates an increased risk for ischemic nonlacunar stroke. Among the cardiometabolic risk factors and their biomarkers, ApoAI and ApoB have the strongest association with carotid atherosclerosis. Apolipoprotein B and metabolic syndrome have the strongest association with a heterogeneous and hypoechogenic carotid plaque. Elevated CRP in patients with acute ischemic stroke may be a sign of carotid plaque destabilization and can indicate a significant carotid stenosis.</p>
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Contraste por microbolhas em ultrassonografia no diagnóstico diferencial entre oclusão e pseudo-oclusão da artéria carótida interna: correlação com a  angiotomografia / Ultrasound microbubble contrast for distinguishing the diagnosis of cervical internal carotid artery occlusion from the one of pseudo-occlusion utilizing computerized angiotomography as the gold standard

Pinto, Carlos Augusto Ventura 27 October 2010 (has links)
Objetivo: Avaliar a eficácia da ultrassonografia com contraste (US com contraste) de segunda geração no diagnóstico diferencial entre oclusão e pseudo-oclusão de artéria carótida interna cervical (ACI) comparativamente à ultrassonografia com Doppler (US Doppler) utilizando a angiotomografia computadorizada (angio-TC) como padrão-ouro. Materiais e Métodos: Estudo prospectivo realizado entre junho de 2006 e junho de 2008 com 72 pacientes sintomáticos (57; 15) e 78 com ACIs aparentemente ocluídas pela US Doppler. Esses pacientes foram submetidos inicialmente à US Doppler e, em seguida, à US com contraste. Todos os pacientes realizaram posteriormente a angio-TC, utilizada como padrão-ouro. A correlação entre os métodos foi feita através de estudo duplo cego. Resultados: A sensibilidade, a especificidade e a acurácia da US com contraste foram respectivamente de 100%; 90,5% e 97,4%. Quando comparada à angio-TC, a quantidade de falsas oclusões pela US Doppler foi de 26,9% (21/78), (p < 0,001), enquanto que pela US com contraste foi de 2,6% (2/78) (p = 0,500). A US com contraste obteve melhor resultado que a US Doppler, com diferença estatisticamente significante (p < 0,001). Conclusão: A US com contraste é tão eficaz quanto a angio-TC e superior à US Doppler no diagnóstico diferencial entre oclusão e pseudo-oclusão da ACI / Purpose: Evaluate the efficacy of second-generation contrast ultrasound (CEUS) for distinguishing the diagnosis of cervical internal carotid artery (ICA) occlusion from the one of pseudo-occlusion when compared with Doppler Ultrasound (DUS) utilizing computerized angiotomography (CTA) as the gold standard. Material and Methods: A prospective study was performed between June 2006 and June 2008 with 72 symptomatic patients (57 males; 15 females) and 78 ICAs apparently occluded by DUS. These patients were initially subjected to DUS and then to CEUS. All patients went through CTA later on, used as the gold standard. Correlation between the methods was made by means of a double-blind study. Results: The sensitivity, specificity and accuracy of CEUS were taken as 100%, 90.5% and 97.4% respectively. When compared with CTA the amount of false occlusions by DUS was 26.9% (21/78), (p < 0.001) whereas by CEUS 2.6% (2/78) (p = 0.500) was seen. Far better results were obtained with CEUS than with DUS with a significant discrepancy (p < 0.001). Conclusion: CEUS shows to be as effective as CTA but better than DUS for distinguishing the diagnosis of ICA occlusion from the one of pseudo-occlusion

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