Since December 2019, coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in considerable morbidity and mortality in more than 30 countries worldwide. Recently, COVID-19–associated clusters of severe respiratory illness have been independently associated with risk of mortality, and mounting evidence substantiates the presence of cardiac injury in patients with COVID-19.^1,2 Although a recent study reported that 12% of patients had COVID-19–associated acute cardiac injury,¹ manifesting as an ejection fraction decline and troponin I elevation, and the American College of Cardiology clinical bulletin has highlighted the cardiac implications of COVID-19,³ the association between COVID-19–associated cardiac injury and risk of mortality remains unclear. The present study therefore retrospectively analyzed data from a single center in Wuhan, China, to examine the potential association between cardiac injury and mortality among patients with COVID-19.

Aims: To investigate the characteristics and clinical significance of myocardial injury in patients with severe coronavirus disease 2019 (COVID-19). Methods and results: We enrolled 671 eligible hospitalized patients with severe COVID-19 from 1 January to 23 February 2020, with a median age of 63 years. Clinical, laboratory, and treatment data were collected and compared between patients who died and survivors. Risk factors of death and myocardial injury were analysed using multivariable regression models. A total of 62 patients (9.2%) died, who more often had myocardial injury (75.8% vs. 9.7%; P < 0.001) than survivors. The area under the receiver operating characteristic curve of initial cardiac troponin I (cTnI) for predicting in-hospital mortality was 0.92 [95% confidence interval (CI), 0.87–0.96; sensitivity, 0.86; specificity, 0.86; P < 0.001]. The single cut-off point and high level of cTnI predicted risk of in-hospital death, hazard ratio (HR) was 4.56 (95% CI, 1.28–16.28; P = 0.019) and 1.25 (95% CI, 1.07–1.46; P = 0.004), respectively. In multivariable logistic regression, senior age, comorbidities (e.g. hypertension, coronary heart disease, chronic renal failure, and chronic obstructive pulmonary disease), and high level of C-reactive protein were predictors of myocardial injury. Conclusion: The risk of in-hospital death among patients with severe COVID-19 can be predicted by markers of myocardial injury, and was significantly associated with senior age, inflammatory response, and cardiovascular comorbidities.

Cardiac dysfunction is a common complication of sepsis, and is attributed to severe inflammatory responses. Ferroptosis is reported to be involved in sepsis-induced cardiac inflammation. Therefore, we speculated that ferrostatin-1 (Fer-1), a ferroptosis inhibitor, improves cardiac dysfunction caused by sepsis. An intraperitoneal injection of lipopolysaccharide (LPS) was performed to induce a rat cardiac dysfunction model. Echocardiography, cardiac histopathology, biochemical and western blot results were analyzed. Twelve hours after the LPS injection, LPS-treated rats exhibited deteriorating cardiac systolic function, increased levels of cardiac injury markers and levels of ferroptosis markers prostaglandin endoperoxide synthase 2 (PTGS2). Additionally, LPS increased iron deposition in the myocardium, with downregulating ferroportin (FPN, SLC40A1) and transferrin receptor (TfR)expression, and upregulating ferritin light chain (FTL) and ferritin heavy chain (FTH1) expression. Meanwhile, LPS also increased lipid peroxidation in the rat heart by decreasing the expression of glutathione peroxidase 4 (GPX4). Moreover, the expression of inflammatory cytokines, such as tumor necrosis-alpha (TNF-α), interleukin-1 (IL-1β), and interleukin-6 (IL-6), and inflammatory cell infiltration were also increased following LPS challenge. Finally, the abovementioned adverse effects of LPS were relieved by Fer-1 except for TfR expression. Mechanistically, Fer-1 significantly reduced the levels of toll-like receptor 4 (TLR4), phospho-nuclear factor kappa B (NF-κB), and phospho-inhibitor of kappa Bα (IκBα) in LPS-treated rats. In summary, these findings imply that Fer-1 improved sepsis-induced cardiac dysfunction at least partially via the TLR4/NF-κB signaling pathway.

Atrial fibrillation (AF) is the most common persistent cardiac arrhythmia. This study aimed to estimate its prevalence and explore associated factors in adults aged 18 years or older in China. Study data were derived from a national sample from July 2020 to September 2021. Participants were recruited using a multistage stratified sampling method from twenty-two provinces, autonomous regions, and municipalities in China. AF was determined based on a history of diagnosed AF or electrocardiogram results. A total of 114,039 respondents were included in the final analysis with a mean age of 55 years (standard deviation 17), 52·1% of whom were women. The crude prevalence of AF was 2·3% (95% confidence interval [CI] 1·7-2·8) and increased with age. The age-standardized AF prevalence was 1·6% (95% CI 1·6-1·7%) overall, and 1·7% (1·6-1·8%), 1·4% (1·3-1·5%), 1·6% (95% CI 1·5-1·7%), and 1·7% (1·6-1·9%) in men, women, urban areas, and rural areas, respectively. The prevalence was higher in the central regions (2·5%, 2·3-2·7%) than in the western regions (1·5%, 1·0-2·0%) and eastern regions (1·1%, 1·0-1·2%) in the overall population, either in the gender or residency subgroups. The associated factors for AF included age (per 10 years; odds ratio 1·41 [95% CI 1·38-1·46]; p < 0·001), men (1·34 [1·24-1·45]; p < 0·001), hypertension (1·22 [1·12-1·33]; p < 0·001), coronary heart disease (1·44 [1·28-1·62]; p < 0·001), chronic heart failure (3·70 [3·22-4·26]; p < 0·001), valvular heart disease (2·13 [1·72-2·63]; p < 0·001), and transient ischaemic attack/stroke (1·22 [1·04-1·43]; p = 0·013). The prevalence of AF was 1.6% in the Chinese adult population and increased with age, with significant geographic variation. Older age, male sex, and cardiovascular disease were potent factors associated with AF. It is crucial to increase the awareness of AF and disseminate standardized treatment in clinical settings to reduce the disease burden. This research was supported the Nature Science Foundation of Hubei province (No: 2017CFB204).

Cold-inducible RNA-binding protein (CIRP) is a cold-shock protein which can be induced after exposure to a moderate cold-shock in different species ranging from amphibians to humans. Expression of CIRP can also be regulated by hypoxia, UV radiation, glucose deprivation, heat stress and H2O2, suggesting that CIRP is a general stress-response protein. In response to stress, CIRP can migrate from the nucleus to the cytoplasm and regulate mRNA stability through its binding site on the 3′-UTR of its targeted mRNAs. Through the regulation of its targets, CIRP has been implicated in multiple cellular process such as cell proliferation, cell survival, circadian modulation, telomere maintenance and tumor formation and progression. In addition, CIRP can also exert its functions by directly interacting with intracellular signaling proteins. Moreover, CIRP can be secreted out of cells. Extracellular CIRP functions as a damage-associated molecular pattern to promote inflammatory responses and plays an important role i... Lay abstract Cold-inducible RNA-binding protein is a protein that can be be regulated by a variety of stress factors, such as cold temperature and UV radiation. Its response to stress is implicated in multiple cellular process such as cell proliferation, cell survival, circadian modulation, telomere maintenance and tumor formation and progression. It can also travel outside the cell where it can be involved in inflammatory diseases. This review summarizes our current knowledge of cold-inducible RNA-binding protein and its actions, what we have yet to understand and its potential for use in treatment of diseases ranging from cancer to diabetes.