Achados ao ecocardiograma transtorácico em pacientes hospitalizados com COVID- 19: resultados do registro brasileiro de ecocardiografia durante a pandemia de COVID-19 (ECOVID) / Transthoracic echocardiography findings of hospitalized patients with COVID-19: results from the brazilian echocardiography registry during the COVID-19 Pandemic (ECOVID)

Fundamento: A ecocardiografia transtorácica (ETT) pode desempenhar um papel crucial na avaliação das manifestações cardíacas da COVID-19. Objetivo: Nosso objetivo foi relatar a prevalência das principais anormalidades ecocardiográficas em pacientes hospitalizados com COVID-19. Métodos: Realizou-se estudo observacional multicêntrico prospectivo com pacientes com COVID-19 submetidos a ETT durante a internação. Pacientes com insuficiência cardíaca prévia, doença arterial coronariana ou fibrilação atrial foram classificados como portadores de doença cardiovascular (DCV) prévia. Foram coletados dados clínicos e ecocardiográficos da estrutura e da função cardíaca. Resultados: Avaliamos 310 pacientes com COVID-19, com 62±16 anos de idade, 61% homens, 53% com hipertensão arterial, 33% com diabetes e 23% com DCV prévia. No total, 65% dos pacientes necessitaram de suporte em unidade de terapia intensiva. As alterações ecocardiográficas mais prevalentes foram hipertrofia do ventrículo esquerdo (VE) (29%), hipertensão pulmonar (25%), disfunção sistólida do VE (16,5%), disfunção sistólica do ventrículo direito (VD) (15,9%), disfunção diastólica do VE grau II/III (11%) e alteração da contratilidade regional do VE (11%). Derrame pericárdico foi incomum (7%). Hipertrofia do VE (25 vs. 45%, p=0,001), disfunção sistólica do VE (11 vs. 36%, p<0,001), alterações da contratilidade regional (6 vs. 29%, p<0,001), disfunção diastólica do VE grau II/III (9 vs. 19%, p=0,03) e hipertensão pulmonar (22 vs. 36%, p=0,019) foram menos comuns nos pacientes sem do que com DCV prévia. A disfunção sistólica do VD mostrou-se semelhante em pacientes sem e com DCV prévia (13 vs. 25%, p=0,07). Conclusões: Entre os pacientes hospitalizados com COVID-19, os achados ecocardiográficos anormais foram comuns, porém menos encontrados naqueles sem DCV. A disfunção sistólica do VD pareceu afetar de forma semelhante pacientes com e sem DCV prévia. (AU)

Background: Transthoracic echocardiography (TTE) may play a crucial role in the evaluation of cardiac manifestations of coronavirus disease 2019 (COVID-19). Objective: We aimed to report the prevalence of the main echocardiographic abnormalities of hospitalized COVID-19 patients. Methods: We performed a prospective multicenter observational study in patients with COVID-19 who underwent TTE during hospitalization. Patients with pre-existing heart failure, coronary artery disease, or atrial fibrillation were categorized as having previous cardiovascular disease (CVD). Clinical and echocardiographic data about cardiac structure and function were collected. Results: We evaluated 310 patients with COVID-19 (mean age, 62±16 years; 61% men; 53% with arterial hypertension; 33% with diabetes; and 23% with previous CVD). Overall, 65% of the patients required intensive care unit support. The most prevalent echocardiographic abnormalities were LV hypertrophy (29%), pulmonary hypertension (25%), left ventricular (LV) systolic dysfunction (16.5%), right ventricular (RV) systolic dysfunction (15.9%), grade II/III LV diastolic dysfunction (11%), and LV regional wall motion abnormality (11%). Pericardial effusion was uncommon (7% of cases). LV hypertrophy (25% vs. 45%, p=0.001), LV systolic dysfunction (11% vs. 36%, p<0.001), regional wall motion abnormalities (6% vs. 29%, p<0.001), grade II/III LV diastolic dysfunction (9% vs. 19%, p=0.03), and pulmonary hypertension (22% vs. 36%, p=0.019) were less common in patients without previous CVD. RV systolic dysfunction occurred at similar frequencies in patients with versus without previous CVD (13% vs. 25%, p=0.07). Conclusions: Among patients hospitalized with COVID-19, abnormal echocardiographic findings were common, but less so among those without previous CVD. RV systolic dysfunction appeared to affect similar proportions of patients with versus without previous CVD. (AU)

A fingerprint of amyloid plaques in a bitransgenic animal model of Alzheimer's disease obtained by statistical unmixing analysis of hyperspectral Raman data.

The global prevalence of Alzheimer's disease (AD) points to endemic levels, especially considering the increase of average life expectancy worldwide. AD diagnosis based on early biomarkers and better knowledge of related pathophysiology are both crucial in the search for medical interventions that are able to modify AD progression. In this study we used unsupervised spectral unmixing statistical techniques to identify the vibrational spectral signature of amyloid ß aggregation in neural tissues, as early biomarkers of AD in an animal model. We analyzed spectral images composed of a total of 55 051 Raman spectra obtained from the frontal cortex and hippocampus of five bitransgenic APPswePS1ΔE9 mice, and colocalized amyloid ß plaques by other fluorescence techniques. The Raman signatures provided a multifrequency fingerprint consistent with the results of synthesized amyloid ß fibrils. The fingerprint obtained from unmixed analysis in neural tissues is shown to provide a detailed image of amyloid plaques in the brain, with the potential to be used as biomarkers for non-invasive early diagnosis and pathophysiology studies in AD on the retina.

Probing Spatial Phonon Correlation Length in Post-Transition Metal Monochalcogenide GaS Using Tip-Enhanced Raman Spectroscopy.

The knowledge of the phonon coherence length is of great importance for two-dimensional-based materials since phonons can limit the lifetime of charge carriers and heat dissipation. Here we use tip-enhanced Raman spectroscopy (TERS) to measure the spatial correlation length Lc of the A1g1 and A1g2 phonons of monolayer and few-layer gallium sulfide (GaS). The differences in Lc values are responsible for different enhancements of the A1g modes, with A1g1 always enhancing more than the A1g2, independently of the number of GaS layers. For five layers, the results show an Lc of 64 and 47 nm for A1g1 and A1g2, respectively, and the coherence lengths decrease when decreasing the number of layers, indicating that scattering with the surface roughness plays an important role.