The use of cardiac troponins and B-type natriuretic peptide in COVID-19.

Coronavirus disease 2019 (COVID-19) is still challenging health care systems worldwide. Over time, it has become clear that respiratory disease is not the only important entity as critically ill patients are also more prone to develop complications, such as acute cardiac injury. Despite extensive research, the mainstay of treatment still relies on supportive care and targeted therapy of these complications. The development of a prognostic model which helps clinicians to diverge patients to an appropriate level of care is thus crucial. As a result, several prognostic markers have been studied in the past few months. Among them are the cardiac biomarkers, especially cardiac troponins T/I and brain natriuretic peptide, which seem to have important prognostic values as several reports have confirmed their strong association with adverse clinical outcomes and death. The use of these biomarkers as part of a prognostic tool could potentially result in more precise risk stratification of COVID-19 patients and divergence to an adequate level of care. However, several caveats persist causing international guidelines to still recommend in favour of a more conservative approach to cardiac biomarker testing for prognostic purposes.

The TDs/aptamer cTnI biosensors based on HCR and Au/Ti3C2-MXene amplification for screening serious patient in COVID-19 pandemic.

The accurate assay of cardiac troponin I (cTnI) is very important for acute myocardial infarction (AMI), it also can be employed as an effective index for screening serious patients in COVID-19 pandemic before fatal heart injury to reduce the mortality. A ratiometric sensing strategy was proposed based on electrochemiluminescent (ECL) signal of doxorubicin (Dox)-luminol or the electrochemical (EC) signal of methylene blue (MB) vs. referable EC signal of Dox. The bio-recognitive Tro4-aptamer ensures the high specificity of the sensor by affinity binding to catch cTnI, and the tetrahedral DNA (TDs) on Au/Ti3C2-MXene built an excellent sensing matrix. An in situ hybrid chain reaction (HCR) amplification greatly improved the sensitivity. The ratiometric sensing responses ECLDox-luminol/CurrentDox or CurrentMB/CurrentDox linearly regressed to cTnI concentration in the range of 0.1 fM-1 pM or 0.1 fM-500 fM with the limit of detection (LOD) as 0.04 fM or 0.1 fM, respectively. Served as the reference signal, CurrentDox reflected the variation of sensor, it is very effective to ensure the accuracy of detection to obviate the false results. The proposed biosensors show good specificity, sensitivity, reproducibility and stability, have been applied to determine cTnI in real samples with satisfactory results. They are worth looking forward to be used for screening serious patient of COVID-19 to reduce the mortality, especially in mobile cabin hospital.

Prognostic value of right ventricular strain pattern on ECG in COVID-19 patients.

OBJECTIVE: COVID-19 spread worldwide, causing severe morbidity and mortality and this process still continues. The aim of this study to investigate the prognostic value of right ventricular (RV) strain in patients with COVID-19. METHODS: Consecutive adult patients admitted to the emergency room for COVID-19 between 1 and 30 April were included in this study. ECG was performed on hospital admission and was evaluated as blind. RV strain was defined as in the presence of one or more of the following ECG findings: complete or incomplete right ventricular branch block (RBBB), negative T wave in V1-V4 and presence of S1Q3T3. The main outcome measure was death during hospitalization. The relationship of variables to the main outcome was evaluated by multivariable Cox regression analysis. RESULTS: A total of 324 patients with COVID-19 were included in the study; majority of patients were male (187, 58%) and mean age was 64.2 ± 14.1. Ninety-five patients (29%) had right ventricular strain according to ECG and 66 patients (20%) had died. After a multivariable survival analysis, presence of RV strain on ECG (OR: 4.385, 95%CI: 2.226-8.638, p < 0.001), high-sensitivity troponin I (hs-TnI), d-dimer and age were independent predictors of mortality. CONCLUSION: Presence of right ventricular strain pattern on ECG is associated with in hospital mortality in patients with COVID-19.

Baseline characteristics and changes of biomarkers in disease course predict prognosis of patients with COVID-19.

The outbreak of coronavirus disease (COVID-19) has brought great challenges to the world. The objectives of this study were to describe the baseline characteristics and changes of biomarkers of these COVID-19 patients and identify predictive value of the above markers for patient death. Using patient death as the observational endpoints, clinical data of inpatients in a special ward for COVID-19 in Wuhan, China were retrospectively collected. Univariate and multivariate Cox regression analyses were used to evaluate prognostic value of baseline characteristics and laboratory data changes. This study included clinical data of 75 patients. Age, c-reactive protein (CRP) and interleukin-6 levels were independent predictors of patient death. Survivors were characterized as having declining neutrophil counts, D-dimer, N-terminal pronatriuretic peptide, troponin I (TnI) and c-reactive protein levels, while counts of lymphocyte gradually came back. Non-survivors were characterized with increasing white blood cell counts (WBC) and neutrophil counts. Changes of WBC, TnI and interleukin-6 were also independently associated with patient death. Older age, baseline CRP and IL-6 levels may be used as meaningful predictors to identify patients with poor prognosis. Changes of biomarkers should be closely monitored in the management of patients with COVID-19, while constantly increasing levels of WBC, TnI and interleukin-6 in the disease course also predict patient death.

Biomarkers and short-term prognosis in COVID-19.

PURPOSE: The aim of our study was to analyse the short-term prognostic value of different biomarkers in patients with COVID-19. METHODS: We included patients admitted to emergency department with COVID-19 and available concentrations of cardiac troponin I (cTnI), D-dimer, C-reactive protein (CRP) and lactate dehydrogenase (LDH). Patients were classified for each biomarker into two groups (low vs. high concentrations) according to their best cut-off point, and 30-day all-cause death was evaluated. RESULTS: After multivariate adjustment, cTnI ≥21 ng/L, D-dimer ≥1112 ng/mL, CRP ≥10 mg/dL and LDH ≥334 U/L at admission were associated with an increased risk of 30-day all-cause death (hazard ratio (HR) 4.30; 95% CI 1.74-10.58; p = 0.002; HR 3.35; 95% CI 1.58-7.13; p = 0.002; HR 2.25; 95% CI 1.13-4.50; p = 0.021; HR 2.00; 95% CI 1.04-3.84; p = 0.039, respectively). The area under the curve for cTnI was 0.825 (95% CI 0.759-0.892) and, in comparison, was significantly better than CRP (0.685; 95% CI 0.600-0.770; p = 0.009) and LDH (0.643; 95% CI 0.534-0.753; p = 0.006) but non-significantly better than D-dimer (0.756; 95% CI 0.674-0.837; p = 0.115). CONCLUSIONS: In patients with COVID-19, increased concentrations of cTnI, D-dimer, CRP and LDH are associated with short-term mortality. Of these, cTnI provides better mortality risk prediction. However, differences with D-dimer were non-significant.

De novo design of modular and tunable protein biosensors.

Naturally occurring protein switches have been repurposed for the development of biosensors and reporters for cellular and clinical applications1. However, the number of such switches is limited, and reengineering them is challenging. Here we show that a general class of protein-based biosensors can be created by inverting the flow of information through de novo designed protein switches in which the binding of a peptide key triggers biological outputs of interest2. The designed sensors are modular molecular devices with a closed dark state and an open luminescent state; analyte binding drives the switch from the closed to the open state. Because the sensor is based on the thermodynamic coupling of analyte binding to sensor activation, only one target binding domain is required, which simplifies sensor design and allows direct readout in solution. We create biosensors that can sensitively detect the anti-apoptosis protein BCL-2, the IgG1 Fc domain, the HER2 receptor, and Botulinum neurotoxin B, as well as biosensors for cardiac troponin I and an anti-hepatitis B virus antibody with the high sensitivity required to detect these molecules clinically. Given the need for diagnostic tools to track the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)3, we used the approach to design sensors for the SARS-CoV-2 spike protein and antibodies against the membrane and nucleocapsid proteins. The former, which incorporates a de novo designed spike receptor binding domain (RBD) binder4, has a limit of detection of 15 pM and a luminescence signal 50-fold higher than the background level. The modularity and sensitivity of the platform should enable the rapid construction of sensors for a wide range of analytes, and highlights the power of de novo protein design to create multi-state protein systems with new and useful functions.

Cardiac involvement at presentation in patients hospitalized with COVID-19 and their outcome in a tertiary referral hospital in Northern Italy.

The correlation between myocardial injury and clinical outcome in COVID-19 patients is gaining attention in the literature. The aim of the present study was to evaluate the role of cardiac involvement and of respiratory failure in a cohort of COVID-19 patients hospitalized in an academic hospital in Lombardy, one of the most affected Italian (and worldwide) regions by the epidemic. The study included 405 consecutive patients with confirmed COVID-19 admitted to a medical ward from February 25th to March 31st, 2020. Follow-up of surviving patients ended either at hospital discharge or by July 30th, 2020. Myocardial injury was defined on the basis of the presence of blood levels of hs-TnI above the 99th percentile upper reference limit. Respiratory function was assessed as PaO2/FiO2 (P/F) ratio. The primary end-point was death for any cause. During hospitalization, 124 patients died. Death rate increased from 7.9% in patients with normal hs-TnI plasma levels and no cardiac comorbidity to 61.5% in patients with elevated hs-TnI and cardiac involvement (p < 0.001). At multivariable analysis, older age, P/F ratio < 200 (both p < 0.001) and hs-TnI plasma levels were independent predictors of death. However, it must be emphasized that the median values of hs-TnI were within normal range in non-survivors. Cardiac involvement at presentation was associated with poor prognosis in COVID-19 patients, but, even in a population of COVID-19 patients who did not require invasive ventilation at hospital admission, mortality was mainly driven by older age and respiratory failure.