Classification model based on Raman spectra of selected morphological and biochemical tissue constituents for identification of atherosclerosis in human coronary arteries.

This study presents the results of Raman spectroscopy applied to the classification of arterial tissue based on a simplified model using basal morphological and biochemical information extracted from the Raman spectra of arteries. The Raman spectrograph uses an 830-nm diode laser, imaging spectrograph, and a CCD camera. A total of 111 Raman spectra from arterial fragments were used to develop the model, and those spectra were compared to the spectra of collagen, fat cells, smooth muscle cells, calcification, and cholesterol in a linear fit model. Non-atherosclerotic (NA), fatty and fibrous-fatty atherosclerotic plaques (A) and calcified (C) arteries exhibited different spectral signatures related to different morphological structures presented in each tissue type. Discriminant analysis based on Mahalanobis distance was employed to classify the tissue type with respect to the relative intensity of each compound. This model was subsequently tested prospectively in a set of 55 spectra. The simplified diagnostic model showed that cholesterol, collagen, and adipocytes were the tissue constituents that gave the best classification capability and that those changes were correlated to histopathology. The simplified model, using spectra obtained from a few tissue morphological and biochemical constituents, showed feasibility by using a small amount of variables, easily extracted from gross samples.

Fatores de risco para cirurgia de revascularização miocárdica em pacientes com angioplastia coronariana prévia com stent / Risk factors for myocardial revascularization surgery in pacients with prior coronary angioplasty with stent

Este estudo analisou os fatores de risco que possam ter contribuído para a necessidade de cirurgia de revascularização miocárdica nos pacientes após angioplastia coronariana com stent convencional, em um serviço de alta complexidade em cardiologia no oeste de Santa Catarina. O estudo configura-se como caso-controle, não pareado, com variáveis coletadas através dos prontuários e via telefone. Os pacientes que realizaram cirurgia de revascularização miocárdica com angioplastia coronariana prévia com stent convencional, no período de 2009-2013, constituem os casos e os que efetuaram apenas angioplastia coronariana com stent convencional, no período de 2011-2012, os controles. Para cada caso foram selecionados quatro controles. Avaliou-se 175 pacientes, sendo 35 casos e 140 controles, sendo aproximadamente 60% da população homens. Dentre os fatores de risco analisados, a hipertensão arterial sistêmica e a dislipidemia foram mais frequentes nos casos que nos controles (100% vs. 72,9%, p< 0,01 e 97,1% vs. 66,4%, p< 0,01, respectivamente). A hipertensão arterial sistêmica e a dislipidemia são fatores de risco para necessidade de cirurgia de revascularização miocárdica após angioplastia coronariana com stent convencional. As demais variáveis não apresentaram significância para a evolução a cirurgia.

This study analyzed the risk factors that may have contributed to the need for myocardial revascularization surgery in patients after percutaneous transluminal coronary angioplasty with conventional stent, in a high complexity cardiology service in Western Santa Catarina. The study is characterized as a case-control study, unpaired, with variables collected through medical records and by telephone. The patients who underwent myocardial revascularization surgery with percutaneous transluminal coronary angioplasty with prior conventional stents in the period 2009-2013 constitute the cases, and the ones who have only percutaneous transluminal coronary angioplasty with conventional stent in the period of 2011-2012 constitute the controls. For each case it was selected four controls. It were assessed 175 patients, being that 35 were cases and 140 were controls, approximately 60% of the population men. Among the risk factors analyzed, systemic arterial hypertension and dyslipidemia were more frequent in cases than in controls (100 % vs. 72.9 %, p < 0.01 and 97.1 % vs. 66.4 %, p < 0.01, respectively). The systemic arterial hypertension and dyslipidemia are risk factors for the need of myocardial revascularization surgery after percutaneous transluminal coronary angioplasty with conventional stent. The other variables had no significance for the evolution to a surgery.