Submitted by PPG Medicina e Ci?ncias da Sa?de (medicina-pg@pucrs.br) on 2018-05-15T11:37:17Z No. of bitstreams: 1 RICARDO_MEDEIROS_PIANT?.pdf: 4074123 bytes, checksum: 97d3d6422fb7d0e0e6563a995eea242c (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2018-05-28T14:35:12Z (GMT) No. of bitstreams: 1 RICARDO_MEDEIROS_PIANT?.pdf: 4074123 bytes, checksum: 97d3d6422fb7d0e0e6563a995eea242c (MD5) / Made available in DSpace on 2018-05-28T14:39:51Z (GMT). No. of bitstreams: 1 RICARDO_MEDEIROS_PIANT?.pdf: 4074123 bytes, checksum: 97d3d6422fb7d0e0e6563a995eea242c (MD5) Previous issue date: 2018-01-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Cardiovascular diseases are one of the most prevalent diseases worldwide and the main cause of mortality in Brazil. They are responsible for 34% of the deaths in America. The most prevalent cardiovascular disorder are ischemic heart disease, stroke, cardiac insufficiency and arterial systemic hypertension. The risk stratification for patients submitted to cardiac surgery comprehends pre operatory risks, mainly. However, during intraoperative period several factors, including surgical technique, myocardial protection and cardiopulmonary bypass may interfere in post-operative results. Thus, intraoperative monitoring and early intervention may improve cardiac surgery outcomes. The increase of serum biomarkers levels indicates myocardial lesion and even necrosis in subjects submitted to cardiac surgery. The biomarker concentration may be related to an adverse outcome. Blood level measures of lactate can also be used as a marker to assess adequate tissue perfusion; providing the magnitude of anaerobic metabolism and tissue oxygenation deficiency. The microRNAs (miRNAs) are part of a non-coding endogenous class of RNAs that act as potent post-transcriptional regulators of gene expression. Moreover, miRNAs present characteristics that make them good biomarkers with high levels of sensibility and specificity allowing early detection of pathological states. In addition, they also change in accordance to the disease course and have a long half-life in the sample enabling an easy laboratory detection. This study identified the profile of cardiac biomarkers such as CK-MB, troponin I and lactate in 115 patients submitted to cardiac surgery and its correlation with the outcome. It was analyzed the expression of miRNAs 1, 133a and 499 expression in 24 individuals as well as the correlation between the biochemical and molecular biomarkers. A correlation of miRNA-1 with troponin I (r = 0.4893, P = 0.0025) and lactate (r = 0.5689, P = 0.0002) was found, which pointed to the first evidence that a miRNA is related to the state of hypoperfusion and tissue oxygenation, monitored by serum lactate. These data will allow the potential of these complex nucleotides to be explored in future studies for the diagnosis, monitoring and therapy of the most diverse pathologies and cardiac surgeries. / As doen?as cardiovasculares s?o prevalentes mundialmente e, no Brasil, s?o respons?veis pela principal causa de mortalidade, superando as neoplasias e as doen?as pulmonares. Elas s?o respons?veis por 34% das causas de morte, com dados semelhantes em toda a Am?rica. As doen?as cardiovasculares mais significativas s?o a cardiopatia isqu?mica, o acidente vascular encef?lico, a insufici?ncia card?aca e a hipertens?o arterial sist?mica. A estratifica??o de risco dos pacientes submetidos ? cirurgia card?aca abrange principalmente os fatores de risco pr?-operat?rios. Entretanto, durante o transoperat?rio, v?rios fatores, incluindo a t?cnica cir?rgica, a prote??o mioc?rdica e a pr?pria circula??o extracorp?rea podem modificar o destino do p?s-operat?rio. Portanto, a monitoriza??o transoperat?ria desses fatores e uma interven??o precoce podem melhorar os resultados na cirurgia card?aca. Em pacientes que s?o submetidos ? cirurgia card?aca, a eleva??o de biomarcadores s?ricos indica les?o e at? mesmo necrose mioc?rdica, sendo que a magnitude do aumento da concentra??o do biomarcador provavelmente esteja relacionada com um desfecho desfavor?vel. A medida dos n?veis sangu?neos de lactato tamb?m pode ser usada como um marcador para avaliar a adequada perfus?o tecidual, fornecendo uma indica??o da magnitude do metabolismo anaer?bico e da defici?ncia de oxigena??o tecidual. Os microRNAs (miRNAs) fazem parte de uma classe de RNAs end?genos, n?o codificadores de prote?nas, que atuam como potentes reguladores p?s-transcricionais da express?o g?nica. Al?m disso, os miRNAs apresentam caracter?sticas que os tornam bons biomarcadores, como alto grau de sensibilidade e especificidade, permitindo a detec??o precoce de estados patol?gicos, al?m de se alterarem de acordo o curso da doen?a e t?m uma longa meia-vida na amostra, sendo rapidamente detectados em laborat?rio. O presente estudo identificou o comportamento dos biomarcadores card?acos CK-MB, troponina I e lactato em 115 pacientes submetidos ? cirurgia card?aca e sua correla??o com os desfechos desfavor?veis. Em 24 desses pacientes foi analisada a express?o dos miRNAs 1, 133a e 499 e estabelecida a correla??o entre esses dois grupos de marcadores. Foi identificada correla??o do miRNA-1 com a troponina I (r=0,4893, P=0,0025) e com o lactato (r=0,5689, P=0,0002), que apontou para a primeira evid?ncia de que um miRNA se relaciona com o estado de hipoperfus?o e oxigena??o tecidual, monitorados pelo lactato s?rico. Esses dados permitir?o que se explore, em futuros estudos, o potencial desses complexos nucleot?deos para o diagn?stico, monitoramento e terapia das mais diversas patologias e cirurgias card?acas.