Profile of serum microRNAs in heart failure with reduced and preserved ejection fraction: Correlation with myocardial remodeling.

Background and aims: Cardiomyocyte hypertrophy and interstitial fibrosis are key components of myocardial remodeling in Heart Failure (HF) with preserved (HFpEF) or reduced ejection fraction (HFrEF). MicroRNAs (miRNAs) are non-coding, evolutionarily conserved RNA molecules that may offer novel insights into myocardial remodeling. This study aimed to characterize miRNA expression in HFpEF (LVEF ≥ 45%) and HFrEF (LVEF < 45%) and its association with myocardial remodeling. Methods: Prospectively enrolled symptomatic HF patients (HFpEF:n = 36; HFrEF:n = 31) and controls (n = 23) underwent cardiac magnetic resonance imaging with T1-mapping and circulating miRNA expression (OpenArray system). Results: 13 of 188 miRNAs were differentially expressed between HF groups (11 downregulated in HFpEF). Myocardial extracellular volume (ECV) was increased in both HF groups (HFpEF 30 ± 5%; HFrEF 30 ± 3%; controls 26 ± 2%, p < 0.001). miR-128a-3p, linked to cardiac hypertrophy, fibrosis, and dysfunction, correlated positively with ECV in HFpEF (r = 0.60, p = 0.01) and negatively in HFrEF (r = -0.51, p = 0.04). miR-423-5p overexpression, previously associated HF mortality, was inversely associated with LVEF (r = - 0.29, p = 0.04) and intracellular water lifetime (τic) (r = -0.45, p < 0.05) in both HF groups, and with NT-proBNP in HFpEF (r = -0.63, p < 0.01). Conclusions: miRNA expression profiles differed between HF phenotypes. The differential expression and association of miR-128a-3p with ECV may reflect the distinct vascular, interstitial, and cellular etiologies of HF phenotypes.

Increased Serum Mir-150-3p Expression Is Associated with Radiological Lung Injury Improvement in Patients with COVID-19.

Coronavirus disease 2019 (COVID-19) is caused by the SARS-CoV-2 virus, responsible for an atypical pneumonia that can progress to acute lung injury. MicroRNAs are small non-coding RNAs that control specific genes and pathways. This study evaluated the association between circulating miRNAs and lung injury associated with COVID-19. Methods: We evaluated lung injury by computed tomography at hospital admission and discharge and the serum expression of 754 miRNAs using the TaqMan OpenArray after hospital discharge in 27 patients with COVID-19. In addition, miR-150-3p was validated by qRT-PCR on serum samples collected at admission and after hospital discharge. Results: OpenArray analysis revealed that seven miRNAs were differentially expressed between groups of patients without radiological lung improvement compared to those with lung improvement at hospital discharge, with three miRNAs being upregulated (miR-548c-3p, miR-212-3p, and miR-548a-3p) and four downregulated (miR-191-5p, miR-151a-3p, miR-92a-3p, and miR-150-3p). Bioinformatics analysis revealed that five of these miRNAs had binding sites in the SARS-CoV-2 genome. Validation of miR-150-3p by qRT-PCR confirmed the OpenArray results. Conclusions: The present study shows the potential association between the serum expression of seven miRNAs and lung injury in patients with COVID-19. Furthermore, increased expression of miR-150 was associated with pulmonary improvement at hospital discharge.

Diffuse Myocardial Fibrosis and Cardiomyocyte Diameter Are Associated With Heart Failure Symptoms in Chagas Cardiomyopathy.

Background: Chronic Chagas cardiomyopathy (CCC) constitutes the most life-threatening consequence of the Trypanosoma cruzi infection. Our goal was to test in CCC the associations of the myocardial tissue phenotype with cardiac dysfunction, and heart failure (HF) severity, using cardiac magnetic resonance (CMR). Methods: We performed a prospective observational cohort of patients with consecutive CCC with a CMR protocol, including ventricular function, myocardial T1, and late gadolinium enhancement (LGE). Extracellular volume (ECV), and intracellular water lifetime, τic, a measure of cardiomyocyte diameter, were compared to CCC disease progression, including Rassi score and New York Heart Association (NYHA) class. An exploratory prognostic analysis was performed to investigate the association of both ECV and τic with CV death. Results: A total of 37 patients with intermediate-to-high-risk CCC were enrolled (Chagas Rassi score ≥7, mean left ventricle (LV) ejection fraction (EF) 32 ± 16%). Myocardial ECV (0.40 ± 0.07) was correlated with Rassi score (r = 0.43; P = 0.009), higher NYHA class, and LV EF (r = -0.51; P = 0.0015). τic decreased linearly with NYHA class (P = 0.007 for non-parametric test of linear trend) and showed a positive association with LV EF (r = 0.47; P = 0.004). Over a median follow-up of 734 days (range: 6-2,943 days), CV death or cardiac transplantation occurred in 10 patients. The Rassi score (heart rate [HR] = 1.3; 95% CI = [1.0, 1.8]; P = 0.028) and ECV (HR = 3.4 for 0.1 change, 95% CI = [1.1, 11.0], P = 0.039) were simultaneously associated with CV death. Conclusion: In patients with intermediate-to-high-risk CCC, an expanded ECV and regression of cardiomyocyte diameter were associated with worsening systolic function and HF severity, respectively. The exploratory analysis indicates that ECV may have a prognostic value to identify patients with CCC at a higher risk for cardiovascular events.