Resumo Embora o modelo existente de classificação do infarto agudo do miocárdio (IAM) em IAMCSST e IAMSSST tenha sido benéfico, considera-se hoje que ele falha em abordar a complexidade das síndromes coronarianas agudas. O estudo tem como objetivo examinar o atual paradigma IAMCSST-IAMSSST e defender um modelo mais detalhado, chamado de oclusão coronariana aguda (OCA) e Ausência de Oclusão Coronária Aguda (NOCA), para um diagnóstico e um manejo do IAM mais precisos. Realizou-se uma análise abrangente da literatura médica existente, com foco nas limitações do modelo IAMCSST-IAMSSST. O estudo também descreve uma nova abordagem diagnóstica para pacientes apresentando do torácica nos departamentos de emergência. O modelo IAMCSST-IAMSSST tradicional falha em prover um diagnóstico preciso e um tratamento efetivo, principalmente na identificação de oclusões da artéria coronária. O modelo OCA-NOCA é mais preciso em termos anatômicos e fisiológicos, e apoiado por pesquisa clínica extensa e opiniões de especialistas. Ele destaca a necessidade de rápida realização de eletrocardiogramas (ECGs) e terapias de reperfusão para casos suspeitos de OCA, visando melhorar os desfechos dos pacientes. O modelo OCA-NOCA abre um novo caminho para pesquisas e aplicações clínicas futuras. Ele defende um entendimento mais abrangente dos mecanismos subjacentes das síndromes coronarianas agudas, levando a planos individualizados de tratamentos. Espera-se que essa nova abordagem incite novos debates e pesquisas acadêmicas, principalmente na área de cardiologia no Brasil, com o objetivo de aumentar a precisão diagnóstica e a eficácia do tratamento de pacientes com IAM. (IAM benéfico considerase considera se agudas IAMCSSTIAMSSST detalhado OCA (OCA NOCA, NOCA , (NOCA) precisos Realizouse Realizou IAMCSSTIAMSSST. IAMSSST. emergência efetivo coronária OCANOCA fisiológicos especialistas ECGs (ECGs futuras tratamentos Esperase Espera acadêmicas Brasil (NOCA

Abstract Although the existing framework for classifying acute myocardial infarction (AMI) into STEMI and NSTEMI has been beneficial, it is now considered to be falling short in addressing the complexity of acute coronary syndromes. The study aims to scrutinize the current STEMI-NSTEMI paradigm and advocate for a more nuanced framework, termed as occlusion myocardial infarction (OMI) and non-occlusion myocardial infarction (NOMI), for a more accurate diagnosis and management of AMI. A comprehensive analysis of existing medical literature was conducted, with a focus on the limitations of the STEMI-NSTEMI model. The study also outlines a new diagnostic approach for patients presenting with chest pain in emergency settings. The traditional STEMI-NSTEMI model falls short in diagnostic precision and effective treatment, especially in identifying acute coronary artery occlusions. The OMI-NOMI framework offers a more anatomically and physiologically accurate model, backed by a wealth of clinical research and expert opinion. It underscores the need for quick ECG assessments and immediate reperfusion therapies for suspected OMI cases, aiming to improve patient outcomes. The OMI-NOMI framework offers a new avenue for future research and clinical application. It advocates for a more comprehensive understanding of the underlying mechanisms of acute coronary syndromes, leading to individualized treatment plans. This novel approach is expected to ignite further scholarly debate and research, particularly in the Brazilian cardiology sector, with the goal of enhancing diagnostic accuracy and treatment effectiveness in AMI patients. (AMI beneficial syndromes STEMINSTEMI (OMI nonocclusion non NOMI, NOMI , (NOMI) conducted settings occlusions OMINOMI opinion cases outcomes application plans sector (NOMI

Ventricular hypertrophy is one of the major myocardial responses to pressure overload (PO). Most studies on early myocardial response focus on the days or even weeks after induction of hypertrophic stimuli. Since mechanotransduction pathways are immediately activated in hearts undergoing increased work load, it is reasonable to infer that the myocardial gene program may be regulated in the first few hours. In the present study, we monitored the expression of some genes previously described in the context of myocardial hypertrophic growth by using the Northern blot technique, to estimate the mRNA content of selected genes in rat myocardium for the periods 1, 3, 6, 12 and 48 h after PO stimuli. Results revealed an immediate switch in the expression of genes encoding alpha and beta isoforms of myosin heavy chain, and up-regulation of the cardiac isoform of alpha actin. We also detected transitory gene regulation as the increase in mitochondrial cytochrome c oxidase 1 gene expression, parallel to down-regulation of genes encoding sarco(endo)plasmic reticulum Ca+2 ATPase and sodium-calcium exchanger. Taken together, these results indicate that initial myocardial responses to increased work load include alterations in the contractile properties of sarcomeres and transitory adjustment of mitochondrial bioenergetics and calcium availability.