3 resultados para Doppler
Resumo:
Enthesitis is the hallmark of spondyloarthritis and is observed in all subtypes. Namely, a wide information on spondyloarthritis abnormalities, including synovitis, bursitis, tendinitis, enthesitis and cortical bone abnormalities (erosions and enthesophytes), can be efficiently perceived by ultrasound power Doppler. Furthermore, several studies on imaging of enthesis showed that imaging techniques are better than clinical examination to detect pathology at asymptomatic enthesis. Vascularized enthesitis detected by ultrasound power Doppler appears to be a valuable diagnostic tool to confirm spondyloarthritis diagnosis. This article focuses on the validity and reliability of ultrasound enthesitis assessment in the management of spondyloarthritis patients.
Resumo:
RESUMO: Este trabalho tentou contribuir para a caracterizao da fisiopatologia da microcirculao coronria em diferentes formas de patologia com o auxlio da ecocardiografia transtorcica. Com a aplicao da ecocardiografia Doppler transtorcica foi efectuado o estudo da reserva coronria da artria descendente anterior e com a ecocardiografia de contraste do miocrdio foram analisados parmetros de perfuso do miocrdio como a velocidade da microcirculao coronria, o volume de sangue miocrdico e a reserva de fluxo miocrdico. Estas tcnicas foram utilizadas em diferentes situaes fisiopatolgicas com particular interesse na hipertrofia ventricular esquerda de diferentes etiologias como a hipertenso arterial, estenose artica e cardiomiopatia hipertrfica. Tambm na diabetes mellitus tipo 2 e na doena coronria aterosclertica, estudmos as alteraes da microcirculao coronria. Com a mesma tcnica de ecocardiografia de contraste do miocrdio foi analisada a perfuso do miocrdio num modelo experimental animal sujeito a uma dieta aterognica. Alm das concluses especficas em relao a cada um dos trabalhos efectuados h a referir como concluses gerais a sua fcil aplicabilidade e exequibilidade em mbito clnico, a sua reprodutibilidade e preciso. Quando comparadas com tcnicas consideradas de referncia mostraram resultados com significativa correlao estatstica. Em todos os doentes e nos grupos controle foi possvel comprovar e quantificar o gradiente de perfuso transmural em repouso e durante a aco de stress vasodilatador, relevando a importncia da perfuso sub-endocrdica na funo do ventrculo esquerdo. O estudo da microcirculao coronria no grupo de doentes com hipertrofia ventricular esquerda revelou que no grupo com hipertenso arterial existe disfuno da microcirculao coronria ainda antes de se observar aumento de massa do ventrculo esquerdo, e que esta disfuno diferente em funo da geometria ventricular. Nos doentes com estenose artica foi demonstrado que alm da disfuno da microcirculao coronria, explicada pelo fenmeno de hipertrofia, existe outro componente extrnseco que depois de corrigido atravs de cirurgia de substituio valvular, conduziu a uma parcial normalizao dos valores de reserva coronria. Na cardiomiopatia hipertrfica observou-se uma grande heterogeneidade de perfuso transmural e foi documentado, em imagens de ecocardiografia de contraste do miocrdio e aps anlise paramtrica, a ausncia de perfuso do miocrdio na regio sub-endocrdica durante o stress vasodilatador de reserva coronria diminudos em fases precoces de evoluo da doena. Foi demonstrado que a reserva coronria na DM2 em fases mais avanadas estava significativamente diminuda. Descrevemos tambm em doentes com DM2 e sem doena coronria angiogrfica a existncia de disfuno da microcirculao coronria. Durante o stress vasodilatador, observmos e documentmos neste grupo de doentes, a existncia de defeitos de perfuso transitrios ou de diminuio da velocidade da microcirculao coronria. No grupo de doentes com doena coronria confirmmos o interesse da avaliao da reserva coronria aps interveno percutnea na definio de prognstico ps EAM, em termos de recuperao funcional do ventrculo esquerdo. Em doentes com BCRE e de difcil estratificao de risco, foi possvel calcular o valor de reserva coronria e estratificar o risco de doena coronria. Num modelo experimental animal demonstrmos a exequibilidade da tcnica de ECM, e verificmos que nessas condies experimentais, uma sobrecarga aterognica na dieta, ao fim de 6 semanas, comprometia severamente a reserva coronria. Estes resultados foram parcialmente reversveis quando dieta foi adicionada uma estatina. Estas tcnicas pela sua no invasibilidade, fcil acesso, repetibilidade e inocuidade perspectivam-se de grande utilidade na caracterizao de doentes com disfuno da microcirculao coronria, nas diferentes reas de diagnstico, teraputica e preveno. A possibilidade de adaptar a tcnica em modelos experimentais animais tambm nos parece poder vir a ter grande utilidade em investigao.----------------ABSTRACT: This work is intended to be a contribution to the study of coronary microcirculation applying new echocardiographic techniques as transthoracic Doppler echocardiography of coronary arteries and myocardial contrast echocardiography. Coronary flow reserve may be assessed by transthoracic Doppler echocardiography, and important functional microcirculation parameters as microcirculation flow velocity, myocardial blood volume and myocardial flow reserve may be evaluated through myocardial contrast echocardiography. Microcirculation was analysed in different pathophysiological settings. We addressed situations with increased left ventricular mass as systemic arterial hypertension, aortic stenosis and hypertrophic cardiomyopathy. Also coronary microcirculation was studied in type 2 Diabetes and in different clinical forms of atherosclerotic coronary artery disease. Specific and detailed conclusions were withdrawn from each experimental work. In the overall it was concluded that these two techniques were important tools to easily assess specific pathophysiological information about coronary microcirculation at bed side which would be difficult to get through other techniques. When compared with gold standard techniques, similar sensibility and specificity was found. Because of their better temporal and spatial resolution it was possible to analyse the importance of transmural perfusion gradients, both in basal and during vasodilatation, and their relation to ischemia, and mechanical wall kinetics, as wall thickening and motion. Coronary microcirculation dysfunction was found in systemic arterial hypertension early evolution stages, also related to different left ventricular geometric patterns. Different etiopathogenical explanations for aortic stenosis coronary microcirculation dysfunction were analysed and compared after aortic valve replacement. Transmural myocardial perfusion heterogeneity pattern was observed in hypertrophic cardiomyopathy which was aggravated during adenosine challenge. Coronary microcirculation dysfunction was diagnosed in type 2 diabetes both with coronary artery disease and with normal angiographic coronary arteries. Dynamic transitory subendocardial perfusion defects with adenosine vasodilatation were visualized in these patients.In patients with left branch block, transthoracic Doppler echocardiography was able to suggest a coronary reserve cut-off value for risk stratification. Also it was possible with this technique to calculate coronary flow reserve and predict restenosis after PTCA Again, in an experimental animal model, applying myocardial contrast echocardiography technique it was possible to study the consequences of an atherogenic diet and statins action on the coronary microcirculation function. Because these techniques are easily performed at bed side, are harmless, use no ionizing radiation and because of their repeatability, reproducibility and accuracythey are promissory tools to assess coronary microcirculation. Both in clinic and research areas these techniques will probably have a role in clinical diagnosis, prevention and therapeutically decision.
Resumo:
RESUMO: Enthesitis is the hallmark of spondyloarthritis (SpA), and is observed in all subtypes. Wide information on SpA abnormalities, including synovitis, tendinitis and enthesitis, can be efficiently perceived by Doppler ultrasound. Furthermore, several studies on imaging of enthesis showed that imaging techniques are better than clinical examination to detect enthesis alterations; and vascularized enthesitis detected by Doppler ultrasound appears to be a valuable diagnostic tool to confirm SpA diagnosis. However, data published until now concerning entheseal elementary alterations that characterize SpA enthesitis (enthesis inflammatory activity) or enthesopathy (permanent structural changes) reflect rather the authors empiric opinion than a methodological validation process. In this sense it seems crucial to identify elementary entheseal lesions associated with activity or damage, in order to improve monitoring and treatment response in SpA patients. The development of better assessment tools is today a challenge and a need in SpA. The first study of this thesis focused on the analysis of the reliability of inter-lector and inter-ultrasonography equipment of Madrid sonography enthesitis index (MASEI). Fundamental data for the remaining unrolling project validity. In the second and third studies we concerned about two entheseal elemental lesions: erosions and bursa. In literature erosions represent a permanent structural damage, being useful for monitoring joint injury, disease activity and therapeutic response in many rheumatic diseases; and to date, this concept has been mostly applied in rheumatoid arthritis (RA). Unquestionably, erosion is a tissue-related damage and a structural change. However, the hypothesis that we decided to test was if erosions represent a permanent structural change that can only grow and worsen over time, as occurs in RA, or a transitory alteration. A longitudinal study of early SpA patients was undertaken, and the Achilles enthesis was used as a model. Our results strongly suggested that previously detected erosions could disappear during the course of the disease, being consistent with the dynamic behavior of erosion over time. Based on these striking results it seems reasonable to suggest that the new-bone formation process in SpA could be associated with the resolution of cortical entheseal erosion over time. These results could also be in agreement with the apparent failure of anti-tumor necrosis factor (TNF) therapies to control bone proliferation in SpA; and with the relation of TNF-, Dickkopf-related protein 1 (Dkk-1) and the regulatory molecule of the Wnt signaling pathway in the bone proliferation in SpA. In the same model, we then proceeded to study the enthesis bursa. Interestingly, the Outcome Measures in Rheumatology Clinical Trials (OMERACT) enthesopathy definition does not include bursa as an elementary entheseal lesion. Nonetheless, bursa was included in 46% of the enthesis studies in a recently systematic literature review, being in agreement with the concept of synovio-entheseal complex that includes the link between enthesitis and osteitis in SpA. It has been clarified in recent data that there is not only a close functional integration of the enthesis with the neighboring bone, but also a connection between enthesitis and synovitis. Therefore, we tried to assess the prevalence and relevance of the bursa-synovial lesion in SpA. Our findings showed a significant increase of Achilles bursa presence and thickness in SpA patients compared to controls (healthy/mechanical controls and RA controls). These results raise awareness to the need to improve the enthesopathy ultrasonographic definition. In the final work of this thesis, we have explored new perspectives, not previously reported, about construct validity of enthesis ultrasound as a possible activity outcome in SpA. We performed a longitudinal Achilles enthesis ultrasound study in patients with early SpA. Achilles ultrasound examinations were performed at baseline, six- and twelve-month time periods and compared with clinical outcome measures collected at basal visit. Our results showed that basal erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are higher in patients with Doppler signal in enthesis, and even that higher basal ESR, CRP and Ankylosing Spondylitis Disease Activity Score (ASDAS) predicted a higher Doppler signal (an ultrasound alteration accepted as representative of inflammation) six months later. Patients with very high disease activity assessed by ASDAS (>3.5) at baseline had significantly higher Achilles total ultrasound score verified at the same time; and ASDAS <1.3 predicted no Doppler signal at six and twelve months. This seems to represent a connection between classical biomarkers and clinical outcomes associated with SpA activity and Doppler signal, not only at the same time, but also for the following months. Remarkably, patients with inactive disease (ASDAS < 1.3) at baseline had no Doppler signal at six and twelve months. These findings reinforce the potential use of ultrasound related techniques for disease progression assessment and prognosis purposes. Intriguingly, Ankylosing Spondylitis Disease Activity Index (BASDAI) didnt show significant differences between different cut-offs concerning ultrasound lesions or Doppler signal, while verified with ASDAS. These results seem to indicate that ASDAS reflects better than BASDAI what happens in the enthesis. The work herein discussed clearly shows the potential utility of ultrasound in enthesis assessment in SpA patients, and can be important for the development of ultrasound activity and structural damage scores for diagnosis and monitoring purposes. Therefore, local promotion of this technique constitutes a medical intervention that is worth being tested in SpA patients for diagnosis, monitoring and prognosis purposes.