Glycated ACE2 receptor in diabetes: open door for SARS-COV-2 entry in cardiomyocyte.

RATIONALE: About 50% of hospitalized coronavirus disease 2019 (COVID-19) patients with diabetes mellitus (DM) developed myocardial damage. The mechanisms of direct SARS-CoV-2 cardiomyocyte infection include viral invasion via ACE2-Spike glycoprotein-binding. In DM patients, the impact of glycation of ACE2 on cardiomyocyte invasion by SARS-CoV-2 can be of high importance. OBJECTIVE: To evaluate the presence of SARS-CoV-2 in cardiomyocytes from heart autopsy of DM cases compared to Non-DM; to investigate the role of DM in SARS-COV-2 entry in cardiomyocytes. METHODS AND RESULTS: We evaluated consecutive autopsy cases, deceased for COVID-19, from Italy between Apr 30, 2020 and Jan 18, 2021. We evaluated SARS-CoV-2 in cardiomyocytes, expression of ACE2 (total and glycosylated form), and transmembrane protease serine protease-2 (TMPRSS2) protein. In order to study the role of diabetes on cardiomyocyte alterations, independently of COVID-19, we investigated ACE2, glycosylated ACE2, and TMPRSS2 proteins in cardiomyocytes from DM and Non-DM explanted-hearts. Finally, to investigate the effects of DM on ACE2 protein modification, an in vitro glycation study of recombinant human ACE2 (hACE2) was performed to evaluate the effects on binding to SARS-CoV-2 Spike protein. The authors included cardiac tissue from 97 autopsies. DM was diagnosed in 37 patients (38%). Fourth-seven out of 97 autopsies (48%) had SARS-CoV-2 RNA in cardiomyocytes. Thirty out of 37 DM autopsy cases (81%) and 17 out of 60 Non-DM autopsy cases (28%) had SARS-CoV-2 RNA in cardiomyocytes. Total ACE2, glycosylated ACE2, and TMPRSS2 protein expressions were higher in cardiomyocytes from autopsied and explanted hearts of DM than Non-DM. In vitro exposure of monomeric hACE2 to 120 mM glucose for 12 days led to non-enzymatic glycation of four lysine residues in the neck domain affecting the protein oligomerization. CONCLUSIONS: The upregulation of ACE2 expression (total and glycosylated forms) in DM cardiomyocytes, along with non-enzymatic glycation, could increase the susceptibility to COVID-19 infection in DM patients by favouring the cellular entry of SARS-CoV2.

Effect of immunosuppression maintenance in solid organ transplant recipients with COVID-19: Systematic review and meta-analysis.

BACKGROUND: The aim of this study was to assess the effect of continuing immune suppressive therapy in solid organ transplant recipients (SOTR) with coronavirus disease 2019 (COVID-19). METHODS: Systematic review and meta-analysis of data on 202 SOTR with COVID-19, published as case reports or case series. We extracted clinical, hemato-chemical, imaging, treatment, and outcome data. RESULTS: Most patients were kidney recipients (61.9%), males (68.8%), with median age of 57 years. The majority was on tacrolimus (73.5%) and mycophenolate (65.8%). Mortality was 18.8%, but an equal proportion was still hospitalized at last follow up. Immune suppressive therapy was withheld in 77.2% of patients, either partially or completely. Tacrolimus was continued in 50%. One third of survivors that continued immunosuppressants were on dual therapy plus steroids. None of those who continued immunosuppressants developed critical COVID-19 disease. Age (OR 1.07, 95% CI 1-1.11, P = .001) and lopinavir/ritonavir use (OR 3.3, 95%CI 1.2-8.5, P = .013) were independent predictors of mortality while immunosuppression maintenance (OR 0.067, 95% CI 0.008-0.558, P = .012) and tacrolimus continuation (OR 0.3, 95% CI 0.1-0.7, P = .013) were independent predictors of survival. CONCLUSIONS: Our data suggest that maintaining immune suppression might be safe in SOTR with moderate and severe COVID-19. Specifically, receiving tacrolimus could be beneficial for COVID-19 SOTR. Because of the quality of the available evidence, no definitive guidance on how to manage SOTR with COVID-19 can be derived from our data.

Adult cardiovascular surgery and the coronavirus disease 2019 (COVID-19) pandemic: the Italian experience.

The coronavirus disease 2019 (COVID-19) pandemic has profoundly affected all health care professionals. The outbreak required a thorough reorganization of the Italian regional local health care system to preserve resources such as ventilators, beds in intensive care units and surgical and anaesthesiological staff. Levels of priority were created, together with a rigorous triage procedure for patients with COVID-19, which led to postponement of all elective procedures. Urgent cases were discussed with the local heart team and percutaneous approaches were selected as the first treatment option to reduce hospital stay. COVID-19 and COVID-19-free pathways were created, including adequate preparation of the operating room, management of anaesthesiological procedures, transportation of patients and disinfection. It was determined that patients with chronic diseases were at increased risk of adverse outcomes. Systemic inflammation, cytokine storm and hypercoagulability associated with COVID-19 increased the risk of heart failure and cardiac death. In this regard, the early use of extracorporeal membrane oxygenation could be life-saving in patients with severe forms of acute respiratory distress syndrome or refractory heart failure. The goal of this paper was to report the Italian experience during the COVID-19 pandemic in the setting of cardiovascular surgery.