CARLOS ALEXANDRE WAINROBER SEGRE
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina - Médico
3 resultados
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- Hypotheses, rationale, design, and methods for evaluation of ischemic preconditioning assessed by sequential exercise tests in diabetic and non-diabetic patients with stable coronary artery disease - a prospective study(2013) REZENDE, Paulo Cury; GARCIA, Rosa Maria Rahmi; UCHIDA, Augusto Hiroshi; COSTA, Leandro Menezes Alves; SCUDELER, Thiago Luis; MELO, Rodrigo Morel Vieira; OIKAWA, Fernando Teiichi Costa; GARZILLO, Cibele Larrosa; LIMA, Eduardo Gomes; SEGRE, Carlos Alexandre Wainrober; FAVARATO, Desiderio; GIRARDI, Priscyla; TAKIUTI, Myrthes; STRUNZ, Celia Cassaro; HUEB, Whady; RAMIRES, Jose Antonio Franchini; KALIL FILHO, RobertoBackground: Ischemic preconditioning is a powerful mechanism of myocardial protection and in humans it can be evaluated by sequential exercise tests. Coronary Artery Disease in the presence of diabetes mellitus may be associated with worse outcomes. In addition, some studies have shown that diabetes interferes negatively with the development of ischemic preconditioning. However, it is still unknown whether diabetes may influence the expression of ischemic preconditioning in patients with stable multivessel coronary artery disease. Methods/Design: This study will include 140 diabetic and non-diabetic patients with chronic, stable coronary artery disease and preserved left ventricular systolic function. The patients will be submitted to two sequential exercise tests with 30-minutes interval between them. Ischemic parameters will be compared between diabetic and non-diabetic patients. Ischemic preconditioning will be considered present when time to 1.0 mm ST-segment deviation is greater in the second of two sequential exercise tests. Exercise tests will be analyzed by two independent cardiologists. Discussion: Ischemic preconditioning was first demonstrated by Murry et al. in dog's hearts. Its work was reproduced by other authors, clearly demonstrating that brief periods of myocardial ischemia followed by reperfusion triggers cardioprotective mechanisms against subsequent and severe ischemia. On the other hand, the demonstration of ischemic preconditioning in humans requires the presence of clinical symptoms or physiological changes difficult to be measured. One methodology largely accepted are the sequential exercise tests, in which, the improvement in the time to 1.0 mm ST depression in the second of two sequential tests is considered manifestation of ischemic preconditioning. Diabetes is an important and independent determinant of clinical prognosis. It's a major risk factor for coronary artery disease. Furthermore, the association of diabetes with stable coronary artery disease imposes worse prognosis, irrespective of treatment strategy. It's still not clearly known the mechanisms responsible by these worse outcomes. Impairment in the mechanisms of ischemic preconditioning may be one major cause of this worse prognosis, but, in the clinical setting, this is not known. The present study aims to evaluate how diabetes mellitus interferes with ischemic preconditioning in patients with stable, multivessel coronary artery disease and preserved systolic ventricular function.
- Troponin in diabetic patients with and without chronic coronary artery disease(2015) SEGRE, Carlos Alexandre Wainrober; HUEB, Whady; GARCIA, Rosa Maria Rahmi; REZENDE, Paulo Cury; FAVARATO, Desiderio; STRUNZ, Celia Maria Cassaro; SPRANDEL, Marilia da Costa Oliveira; ROGGERIO, Alessandra; CARVALHO, Ana Luiza de Oliveira; MARANHAO, Raul Cavalcante; RAMIRES, Jose Antonio Franchini; KALIL FILHO, RobertoBackground: Cardiac-specific troponin detected with the new high-sensitivity assays can be chronically elevated in response to cardiovascular comorbidities and confer important prognostic information, in the absence of unstable coronary syndromes. Both diabetes mellitus and coronary artery disease are known predictors of troponin elevation. It is not known whether diabetic patients with coronary artery disease have different levels of troponin compared with diabetic patients with normal coronary arteries. To investigate this question, we determined the concentrations of a level 1 troponin assay in two groups of diabetic patients: those with multivessel coronary artery disease and those with angiographically normal coronary arteries. Methods: We studied 95 diabetic patients and compared troponin in serum samples from 50 patients with coronary artery disease (mean age = 63.7, 58 % male) with 45 controls with angiographically normal coronary arteries. Brain natriuretic peptide and the oxidative stress biomarkers myeloperoxidase, nitrotyrosine and oxidized LDL were also determined. Results: Diabetic patients with coronary artery disease had higher levels of troponin than did controls (median values, 12.0 pg/mL (95 % CI:10-16) vs 7.0 pg/mL (95 % CI: 5.9-8.5), respectively; p = 0.0001). The area under the ROC curve for the diagnosis of CAD was 0.712 with a sensitivity of 70 % and a specificity of 66 %. Plasma BNP levels and oxidative stress variables (myeloperoxidase, nitrotyrosine, and oxidized LDL) were not different between the two groups. In a multivariate analysis, gender (p = 0.04), serum glucose (0.03) and Troponin I (p = 0.01) had independent statistical significance. Conclusion: Troponin elevation is related to the presence of chronic coronary artery disease in diabetic patients with multiple associated cardiovascular risk factors. Troponin may serve as a biomarker in this high-risk population.
- Hypotheses, rationale, design, and methods for prognostic evaluation of cardiac biomarker elevation after percutaneous and surgical revascularization in the absence of manifest myocardial infarction. A comparative analysis of biomarkers and cardiac magnetic resonance. The MASS-V Trial(2012) HUEB, Whady; GERSH, Bernard J.; REZENDE, Paulo Cury; GARZILLO, Cibele Larrosa; LIMA, Eduardo Gomes; VIEIRA, Ricardo D'Oliveira; GARCIA, Rosa Maria Rahmi; FAVARATO, Desiderio; SEGRE, Carlos Alexandre W.; PEREIRA, Alexandre Costa; SOARES, Paulo Rogerio; RIBEIRO, Expedito; LEMOS, Pedro; PERIN, Marco A.; STRUNZ, Celia Cassaro; DALLAN, Luis A. O.; JATENE, Fabio B.; STOLF, Noedir A. G.; HUEB, Alexandre Ciappina; DIAS, Ricardo; GAIOTTO, Fabio A.; COSTA, Leandro Menezes Alves da; OIKAWA, Fernando Teiichi Costa; MELO, Rodrigo Morel Vieira de; SERRANO JUNIOR, Carlos Vicente; AVILA, Luiz Francisco Rodrigues de; VILLA, Alexandre Volney; PARGA FILHO, Jose Rodrigues; NOMURA, Cesar; RAMIRES, Jose A. F.; KALIL FILHO, RobertoBackground: Although the release of cardiac biomarkers after percutaneous (PCI) or surgical revascularization (CABG) is common, its prognostic significance is not known. Questions remain about the mechanisms and degree of correlation between the release, the volume of myocardial tissue loss, and the long-term significance. Delayed-enhancement of cardiac magnetic resonance (CMR) consistently quantifies areas of irreversible myocardial injury. To investigate the quantitative relationship between irreversible injury and cardiac biomarkers, we will evaluate the extent of irreversible injury in patients undergoing PCI and CABG and relate it to postprocedural modifications in cardiac biomarkers and long-term prognosis. Methods/Design: The study will include 150 patients with multivessel coronary artery disease (CAD) with left ventricle ejection fraction (LVEF) and a formal indication for CABG; 50 patients will undergo CABG with cardiopulmonary bypass (CPB); 50 patients with the same arterial and ventricular condition indicated for myocardial revascularization will undergo CABG without CPB; and another 50 patients with CAD and preserved ventricular function will undergo PCI using stents. All patients will undergo CMR before and after surgery or PCI. We will also evaluate the release of cardiac markers of necrosis immediately before and after each procedure. Primary outcome considered is overall death in a 5-year follow-up. Secondary outcomes are levels of CK-MB isoenzyme and I-Troponin in association with presence of myocardial fibrosis and systolic left ventricle dysfunction assessed by CMR. Discussion: The MASS-V Trial aims to establish reliable values for parameters of enzyme markers of myocardial necrosis in the absence of manifest myocardial infarction after mechanical interventions. The establishments of these indices have diagnostic value and clinical prognosis and therefore require relevant and different therapeutic measures. In daily practice, the inappropriate use of these necrosis markers has led to misdiagnosis and therefore wrong treatment. The appearance of a more sensitive tool such as CMR provides an unprecedented diagnostic accuracy of myocardial damage when correlated with necrosis enzyme markers. We aim to correlate laboratory data with imaging, thereby establishing more refined data on the presence or absence of irreversible myocardial injury after the procedure, either percutaneous or surgical, and this, with or without the use of cardiopulmonary bypass.