Symptoms in post-COVID-19 patients who require hospitalization can persist for months, significantly affecting their health-related quality of life (HRQoL). Thus, the present study aimed to discuss the main findings regarding HRQoL in post-COVID-19 patients who required hospitalization. An electronic search was performed in the MEDLINE, EMBASE, CINAHL, Web of Science, LILACS, and Scopus databases, without date and language restrictions, until July 2021. Twenty-four articles were included in the analysis. It seems that HRQoL partially improved soon after hospital discharge, although the negative impact on HRQoL may persist for months. The physical and mental aspects are affected because patients report pain, discomfort, anxiety, and depression. The HRQoL of COVID-19 infected patients was worse than that of uninfected patients. Additionally, HRQoL seemed worse in patients admitted to the intensive care unit than in those who remained in the ward. Improvements in HRQoL after hospital discharge are independent of imaging improvement, and there seems to be no association between HRQoL after hospital discharge and disease severity on hospital admission. Many factors have been identified as determinants of HRQoL, with women and advanced age being the most related to worse HRQOL, followed by the duration of invasive mechanical ventilation and the need for intensive care. Other factors included the presence and number of comorbidities, lower forced vital capacity, high body mass index, smoking history, undergraduate education, and unemployment. In conclusion, these findings may aid in clinical management and should be considered in the aftercare of patients.

Background: Chronic Chagas cardiomyopathy in humans is characterized by segmental left ventricular wall motion abnormalities ( WMA ), mainly in the early stages of disease. This study aimed at investigating the detection of WMA and its correlation with the underlying histopathological changes in a chronic Chagas cardiomyopathy model in hamsters. Methods and Results: Female Syrian hamsters (n=34) infected with 3.5×10 ⁴ or 10 ⁵ blood trypomastigote Trypanosoma cruzi (Y strain) forms and an uninfected control group (n=7) were investigated. After 6 or 10 months after the infection, the animals were submitted to in vivo evaluation of global and segmental left ventricular systolic function by echocardiography, followed by euthanasia and histological analysis for quantitative assessment of fibrosis and inflammation with tissue sampling in locations coinciding with the left ventricular wall segmentation employed at the in vivo echocardiographic evaluation. Ten of the 34 infected animals (29%) showed reduced left ventricular ejection fraction (<73%). Left ventricular ejection fraction was more negatively correlated with the intensity of inflammation ( r =−0.63; P <0.0001) than with the extent of fibrosis ( r =−0.36; P =0.036). Among the 24 animals with preserved left ventricular ejection fraction (82.9±5.5%), 8 (33%) showed segmental WMA predominating in the apical, inferior, and posterolateral segments. The segments exhibiting WMA , in comparison to those with normal wall motion, showed a greater extent of fibrosis (9.3±5.7% and 7±6.3%, P <0.0001) and an even greater intensity of inflammation (218.0±111.6 and 124.5±84.8 nuclei/mm², P <0.0001). Conclusions: Isolated WMA with preserved global systolic left ventricular function is frequently found in Syrian hamsters with experimental chronic Chagas cardiomyopathy whose underlying histopathological features are mainly inflammatory.

Altered myocardial perfusion is a common finding in chronic Chagas cardiomyopathy (CCC), but its underlying histologic changes have not been elucidated. We investigated the occurrence of myocardial perfusion defects (MPDs) and the correlated regional changes to histology in an experimental model of CCC in hamsters. Methods: Female Syrian hamsters (n = 34) were infected with 3.5 × 10⁴ to 10⁵ trypomastigote forms of Trypanosoma cruzi, Y strain, and 6–10 mo afterward underwent in vivo imaging including resting ^99mTc-sestamibi SPECT, segmental and global left ventricular function assessment using 2-dimensional echocardiography, and ¹⁸F-FDG PET for evaluation of myocardial viability. Histologic analysis included quantification of fibrosis, inflammatory infiltration, and the diameter and density of myocardial microcirculation. Results: MPDs were present in 17 (50%) of the infected animals. Histologic analysis revealed no transmural scar in segments with an MPD, and normal or mildly reduced ¹⁸F-FDG uptake, indicating viable myocardium. Infected animals with an MPD, in comparison to infected animals without an MPD and control animals, showed a lower left ventricular ejection fraction (P = 0.012), a higher wall motion score index (P = 0.004), and a higher extent of inflammatory infiltration (P = 0.018) but a similar extent of fibrosis (P = 0.15) and similar microvascular diameter and density (P > 0.05). Segments with an MPD (n = 65), as compared with normally perfused regions in the same animal (n = 156), showed a higher wall motion score index (P = 0.005) but a similar extent of inflammatory infiltration, a similar extent of fibrosis, and a similar microvascular diameter and density. Conclusion: Resting MPDs are frequent in experimental CCC and are associated with myocardial inflammation but do not designate scar tissue, corresponding to regions with metabolically viable myocardium.

Heart failure induced by myocardial infarct (MI) attenuates the heart rate variability (HRV) and baroreflex sensitivity, which are important risk factors for life-threatening cardiovascular events. Therapies with mesenchymal stem cells (MSCs) have shown promising results after MI. However, the effects of MSCs on hemodynamic (heart rate and arterial pressure) variability and baroreflex sensitivity in chronic heart failure (CHF) following MI have not been evaluated thus far. Male Wistar rats received MSCs or saline solution intravenously 1 week after ligation of the left coronary artery. Control (noninfarcted) rats were also evaluated. MI size was assessed using single-photon emission computed tomography (SPECT). The left ventricular ejection fraction (LVEF) was evaluated using radionuclide ventriculography. Four weeks after MSC injection, the animals were anesthetized and instrumented for chronic ECG recording and catheters were implanted in the femoral artery to record arterial pressure. Arterial pressure and HRVs were determined in time and frequency domain (spectral analysis) while HRV was also examined using nonlinear methods: DFA (detrended fluctuation analysis) and sample entropy. The initial MI size was the same among all infarcted rats but was reduced by MSCs. CHF rats exhibited increased myocardial interstitial collagen and sample entropy combined with the attenuation of the following cardiocirculatory parameters: DFA indices, LVEF, baroreflex sensitivity, and HRV. Nevertheless, MSCs hampered all these alterations, except the LVEF reduction. Therefore, 4 weeks after MSC therapy was applied to CHF rats, MI size and myocardial interstitial fibrosis decreased, while baroreflex sensitivity and HRV improved.