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Background: Cardiac injury is common in hospitalized patients with COVID-19 and portends poorer prognosis. However, the mechanism and the type of myocardial damage associated with SARS-CoV-2 remain uncertain. Methods: We conducted a systematic pathologic analysis of 40 hearts from hospitalized patients dying of Coronavirus Disease 2019 (COVID-19) in Bergamo, Italy to determine the pathologic mechanisms of cardiac injury. We divided the hearts according to presence or absence of acute myocyte necrosis and then determined the underlying mechanisms of cardiac injury. Results: Of the 40 hearts examined, 14 (35%) had evidence of myocyte necrosis, predominantly of the left ventricle. As compared to subjects without necrosis, subjects with necrosis tended to be female, have chronic kidney disease, and shorter symptom onset to admission. The incidence of severe coronary artery disease (i.e., >75% cross sectional narrowing) was not significantly different between those with and without necrosis. 3/14 (21 .4%) subjects with myocyte necrosis showed evidence of acute myocardial infarction defined as ≥1 cm 2 area of necrosis while 11/14 (78.6%) showed evidence of focal (> 20 necrotic myocytes with an area of ≥ 0.05 mm 2 but <1 cm 2 ) myocyte necrosis. Cardiac thrombi were present in 11/14 (78.6%) cases with necrosis, with 2/14 (14.2%) having epicardial coronary artery thrombi while 9/14 (64.3%) had microthrombi in myocardial capillaries, arterioles, and small muscular arteries. We compared cardiac microthrombi from COVID-19 positive autopsy cases to intramyocardial thromboemboli from COVID-19 cases as well as to aspirated thrombi obtained during primary percutaneous coronary intervention from uninfected and COVID-19 infected patients presenting with ST-segment elevation myocardial infarction (STEMI). Microthrombi had significantly greater fibrin and terminal complement C5b-9 immunostaining as compared to intramyocardial thromboemboli from COVID-19 negative subjects and to aspirated thrombi. There were no significant differences between the constituents of thrombi aspirated from COVID-19 positive and negative STEMI patients. Conclusions: The most common pathologic cause of myocyte necrosis was microthrombi. Microthrombi were different in composition as compared to intramyocardial thromboemboli from COVID-19 negative subjects and to coronary thrombi retrieved from COVID-19 positive and negative STEMI patients. Tailored anti-thrombotic strategies may be useful to counteract the cardiac effects of COVID-19 infection.

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Highlights d Adipose tissue memory CD4 + T cells are frequently CD69 + in persons with diabetes d Persons with HIV and diabetes have more CX3CR1 + GPR56 + CD57 + (C-G-C +) CD4 + T cells d Adipose tissue C-G-C + CD4 + T cells and CD69 + CD4 + T cells are clonally expanded d C-G-C + CD4 + T cells are often CMV specific and have more inflammatory transcriptomes

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Objective: Persons with HIV have doubled the risk of developing cardiovascular disease compared with the general population. A persistent and heightened immune response to cytomegalovirus coinfection may be one contributing factor, but the relationship between cytomegalovirus replication, virus-specific immune cells, and plaque burden is unclear. Approach and Results: We assessed the relationship between CD4 + T-cell subsets and carotid plaque burden in a cohort of 70 HIV-positive participants with sustained viral suppression on a single antiretroviral regimen and without known cardiovascular disease. We evaluated the relationship between immune parameters, carotid plaque burden, soluble markers of endothelial activation, and brachial artery flow-mediated vasodilation using multivariable linear and logistic regression models. We found that participants with carotid plaque had increased circulating CX3CR1 + ~GPR56 + ~CD57 + (ie, C~G~C) + CD4 + T cells ( P =0.03), which is a marker combination associated with antiviral and cytotoxic responses. In addition, a median of 14.4% (IQR, 4.7%–32.7%) of the C~G~C + CD4 + T-cells expressed antigen receptors that recognized a single cytomegalovirus glycoprotein-B epitope. Notably, using immunofluorescence staining, we found that CX3CR1 + CD4 + T cells were present in coronary plaque from deceased HIV-positive persons. C-G-C + CD4 + T cells were also present in cells isolated from the aorta of HIV-negative donors. Conclusions: HIV-positive persons with carotid atheroma have a higher proportion of circulating CD4 + T-cells expressing the C~G~C surface marker combination associated with cytotoxic function. These cells can be cytomegalovirus-specific and are also present in the aorta.

Background Cytokine storm-related hypercoagulation may be important in the pathogenesis of stent thrombosis in patients with SARS-CoV-2. Whether stent polymers behave differently under such conditions has never been explored. Methods Fluorinated polymer-nanocoated and uncoated COBRA stents (CeloNova), BioLinx-polymer-coated Resolute Onyx stents (Medtronic), and Synergy stents (Boston Scientific), which are abluminally coated with a bioabsorbable polymer, were exposed to human blood from healthy donors which was supplemented with 400 pg/mL IL-6 and 100 pg/mL TNF-α, similar to what is seen in cytokine storm caused by SARS-CoV-2. Platelet adhesion and neutrophil activation, assessed by immunofluorescence, were compared under cytokine storm and control conditions (untreated blood) ( n = 4 experimental runs). Results Platelet adhesion values, defined as %platelet-covered area x staining intensity, were significantly lower in coated and uncoated COBRA and in Resolute Onyx than in Synergy under control conditions (1.28 × 10 7 ± 0.43 × 10 7 vs. 2.92 × 10 7 ± 0.49 × 10 7 vs. 3.57 × 10 7 ± 0.73 × 10 7 vs. 9.94 × 10 7 ± 0.99 × 10 7 ; p ≤0.0001). In cytokine storm, platelet adhesion values remained low in coated COBRA-PzF (1.78 × 10 7 ± 0.38 × 10 7 ) compared to all other devices (uncoated COBRA: 5.92 × 10 7 ± 0.96 × 10 7 ; Resolute Onyx: 7.27 × 10 7 ± 1.82 × 10 7 ; Synergy: 11.28 × 10 7 ± 1.08 × 10 7 ; p ≤ 0.0001). Although cytokine storm conditions significantly increased neutrophil activation in all stents, it was significantly less in coated and uncoated COBRA, and in Resolute Onyx than in Synergy. Conclusions Blood-biomaterials interactions may determine the thrombogenic potential of stents. Under simulated cytokine storm conditions, fluoropolymer-coated stents showed the most favorable anti-thrombogenic and anti-inflammatory properties.