Cardioprotective effects of vaccination in hospitalized patients with COVID-19 (preprint)

Background COVID-19 vaccination has been shown to prevent and reduce the severity of COVID-19 disease. Aim The aim of this study was to explore the cardioprotective effect of COVID-19 vaccination in hospitalized COVID-19 patients. Methods In this retrospective, single-center cohort study, we included hospitalized COVID-19 patients with confirmed vaccination status from July 2021 to February 2022. We assessed outcomes such as acute cardiac events and cardiac biomarker levels through clinical and laboratory data. Results Our analysis covered 167 patients (69% male, mean age 58 years, 42% being fully vaccinated). After adjustment for confounders, vaccinated hospitalized COVID-19 patients displayed a reduced relative risk for acute cardiac events (RR: 0.33, 95% CI [0.07; 0.75]) and showed diminished troponin T levels (Cohen’s d: -0.52, 95% CI [-1.01; -0.14]), compared to their non-vaccinated peers. Type 2 diabetes (OR: 2.99, 95% CI [1.22; 7.35]) and existing cardiac diseases (OR: 4.31, 95% CI [1.83; 10.74]) were identified as significant risk factors for the emergence of acute cardiac events. Conclusion Our findings suggest that COVID-19 vaccination may confer both direct and indirect cardioprotective effects in hospitalized COVID-19 patients.

SARS-CoV-2 specific T cells induced by both SARS-CoV-2 infection and mRNA vaccination broadly cross-recognize omicron (preprint)

The SARS-CoV-2 variant of concern (VOC) omicron (B1.1.529) is associated with high infectivity and efficient evasion from humoral immunity induced by previous infection or vaccination. In omicron-infected individuals who have been vaccinated or infected before, severe disease seems to be relatively infrequent pointing towards protection by previously primed SARS-CoV-2-specific T cells that cross-recognize omicron. By performing a comprehensive in-depth comparison of the SARS-CoV-2-specific T cell epitope repertoire after natural infection versus after mRNA vaccination, we here demonstrate that spike-derived epitopes are not dominantly targeted in convalescents compared to non-spike epitopes. In vaccinees, however, we detected a broader spike-specific T cell response compared to convalescents reflected by a more diverse repertoire of dominantly targeted spike-specific T cell epitopes. Booster mRNA vaccination induced a broader spike-specific T cell response in convalescents but not in vaccinees with complete initial vaccination. In convalescents and vaccinees, the targeted T cell epitopes are broadly conserved between ancestral and omicron SARS-CoV-2 variants. Hence, our data emphasize the relevance of mRNA vaccine-induced spike-specific CD8+ T cell responses in combating emerging SARS-CoV-2 VOC including omicron and support the benefit of also boosting convalescent individuals with mRNA vaccines.

Combining lung ultrasound and wells score for diagnosing pulmonary embolism in critically ill COVID-19 patients (preprint)

Introduction: Subpleural consolidations have been found in lung ultrasound in patients with COVID-19, possibly deriving from pulmonary embolism (PE). The diagnostic utility of impact of lung ultrasound in critical-ill patients with COVID-19 for PE diagnostics however is unclear.Methods: We retrospectively evaluated all SARS-CoV2-associated ARDS patients admitted to our ICU between March 8th and May 31th 2020. They were enrolled in this study, when a lung ultrasound and a computed tomography pulmonary angiography (CTPA) were documented. In addition, wells score was calculated to estimate the probability of PE. The CTPA was used as the gold standard for the detection of PE. Results: Twenty patients met the inclusion criteria. In 12/20 patients (60%) (sub-) segmental PE were detected by CT-angiography. Lung ultrasound found subpleural consolidations in 90% of patients. PE-typical large supleural consolidations with a size ≥1cm were detectable in 65% of patients and were significant more frequent in patients with PE compared to those without (p=0.035). Large consolidations predicted PE with a sensitivity of 77% and a specificity of 71%. The Wells score was significantly higher in patients with PE compared to those without (2.7±0.8 and 1.7±0.5, respectively, p=0.042) and predicted PE with an AUC of 0.81. When combining the two modalities, comparing patients with considered/probable PE using LUS plus a Wells score ≥2 to patients with possible/unlikely PE in LUS plus a Wells score <2, PE could be predicted with a sensitivity of 100% and a specificity of 80%.Conclusion: Large consolidations detected in lung ultrasound were found frequently in COVID-19 ARDS patients with pulmonary embolism. In combination with a Wells score>2, this might indicate a high-risk for PE in COVID-19.

Intracerebral hemorrhage in COVID-19 patients with pulmonary failure – a propensity score matched registry study (preprint)

Background: Hypercoagulopathy in coronavirus disease 2019 (COVID-19) causing deep vein thrombosis and pulmonary artery embolism necessitate systemic anticoagulation. Case reports of intracerebral hemorrhages in ventilated COVID-19 patients warrant precaution. It is unclear however, if COVID-19 patients with acute respiratory distress syndrome (ARDS) with and without extracorporeal membrane oxygenation therapy (ECMO) have more intracerebral hemorrhages (ICH) compared to other ARDS patients.Methods: We conducted a retrospective observational single center study enrolling all patients with ARDS from 01/2018-05/2020. Patients with ARDS positive for SARS-CoV2 PCR were allocated to the COVID-19 group. Propensity score matching was performed for age, ECMO and risk of bleeding according to HAS-BLED score.Results: A total of 163, mostly severe ARDS patients were identified, 116 (71.2%) without COVID-19 and 47 (28.8%) positive for SARS-CoV-2. The two groups were comparable concerning the main confounders of ICH including age, HAS-BLED score, need for ECMO-therapy as well as anticoagulation levels reported. In 63/163 cases (38.7%), veno-venous ECMO therapy was required and ICU survival was 52.8%. Although HAS-BLED-score on admission was generally low (1.6±1.3), intracerebral hemorrhage was detected in 22 patients (13.5%) with no statistical difference between the groups (11.2 vs. 19.1% with and without SARS-CoV-2, respectively, p=0.21). Propensity score matching confirmed similar intracerebral bleeding rates in both groups (12.8 vs. 19.1% with and without SARS-CoV-2, respectively, p=0.57). Conclusions: Intracerebral hemorrhage was detectable in every tenth patient with ARDS. We found no statistically significant increased bleeding rate in patients with ARDS due to COVID-19 compared to other causes of ARDS.