MicroRNAs are small non-coding RNAs that regulate gene and protein expression. MicroRNAs also regulate several cellular processes such as proliferation, differentiation, cell cycle, apoptosis, among others. In this context, they play important roles in the human body and in the pathogenesis of diseases such as cancer, diabetes, obesity and hypertension. In hypertension, microRNAs act on the renin–angiotensin–aldosterone system, sympathetic nervous system and left ventricular hypertrophy, however the signaling pathways that interact in these processes and are regulated by microRNAs inducing hypertension and the worsening of the disease still need to be elucidated. Thus, the aim of this review is to analyze the pattern of expression of microRNAs in these processes and the possible associated signaling pathways.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces coronavirus-19 disease , has affected many people in Brazil and worldwide. This disease predominantly affects the organs of the respiratory system, but it also damages the brain, liver, kidneys and especially the heart. In the heart, scientific evidence shows that this virus can damage the coronary arteries, generating microvascular dysfunction, favoring acute myocardial infarction. Furthermore, with the increased expression of pro-inflammatory cytokines, it can lead to myocarditis and cardiac fibrosis, inducing changes in the electrical conduction system of the heart, generating cardiac arrhythmias.All these factors mentioned are protagonists in promoting the increase in the mortality outcome. This outcome may be even higher if the individuals are elderly, or if they have other diseases such as type 2 diabetes mellitus or hypertension, because they may already have cardiomyopathy. In this context, this review focused on the impact that COVID-19 can have on the heart and cardiovascular system and the association of this impact with aging, type 2 diabetes mellitus, cardiac arrhythmias and arterial hypertension

Introduction: Chagas disease, an infection caused by the protozoan Trypanosoma cruzi, is an important health problem worldwide that causes cardiac dilation, arrhythmias, and death. Heart failure is a complex syndrome with high morbidity and mortality rates that progresses with similar complications. The New York Heart Association functional classification is used to categorize heart failure severity and stratify heart disease risks and therapies. A reduced left ventricular ejection fraction measured by echocardiography is directly related to a poor prognosis. Objective: To compare the relationship between New York Heart Association functional classification and left ventricular ejection fraction in Chagas versus no Chagas disease outpatients. Methods: Cross-sectional study in a cohort of patients followed at a heart failure clinic. Medical records, clinical interviews, functional classification, and left ventricular ejection fraction by echocardiography were analyzed. The data were filed in a database and analyzed using SPSS software. Results: A total of 127 patients with heart failure were selected from August 2018 to July 2019. Of them, 34 (26.8%) had Chagas disease and 93 (73.3%) had no Chagas disease. There was a predominance of men (53.5%) and patients aged > 60 years (61.4%). There was also a predominance of functional class II. Of the Chagas and no Chagas disease patients, 71% versus 93% had a reduced ejection fraction, 21% versus 6% had a mid-range ejection fraction, and 8% versus 1% had a preserved ejection fraction, respectively. Conclusion: There was an association between advanced functional class and reduced left ventricular ejection fraction, especially in Chagas patients, information that can be used for outpatient follow-up.