COVID-19, Endothelium and the Cardiometabolic Patient: A Possible Role for Capillary Leak Syndrome.

Capillary leak syndrome is an under-diagnosed condition leading to serious hypoalbuminemia with diffuse edema, pulmonary edema, severe hypotension, and possibly death. Sepsis leading to hemophagocytic lymphohistiocytosis (HLH) is a major risk factor; however, capillary hyper-permeability is the core underlying pathophysiological mechanism. Endothelial dysfunction plays a major role in cardiometabolic disease through insulin resistance, lipotoxicity, and, eventually, oxidative stress and chronic inflammation. We review the literature concerning the aforementioned mechanisms as well-established risk factors for adverse COVID-19 outcomes. We especially focus on data regarding the underlying endothelial effects of SARS-CoV-2 infection, including direct damage and increased vascular leakage through a hyper-inflammatory cascade and diminished nitric oxide bioavailability. Interestingly, an increased incidence of hypoalbuminemia has been observed in patients with severe COVID-19, especially those with underlying cardiometabolic disease. Importantly, low albumin levels present a strong, positive association with poor disease outcomes. Therefore, in this review article, we highlight the important role of cardiovascular risk factors on endothelium integrity and the possible link of endothelial damage in the hypoalbuminemia-associated adverse prognosis of COVID-19 patients.

Diabetes and COVID-19; A Bidirectional Interplay.

There seems to be a bidirectional interplay between Diabetes mellitus (DM) and coronavirus disease 2019 (COVID-19). On the one hand, people with diabetes are at higher risk of fatal or critical care unit-treated COVID-19 as well as COVID-19 related health complications compared to individuals without diabetes. On the other hand, clinical data so far suggest that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may result in metabolic dysregulation and in impaired glucose homeostasis. In addition, emerging data on new onset DM in previously infected with SARS-CoV-2 patients, reinforce the hypothesis of a direct effect of SARS-CoV-2 on glucose metabolism. Attempting to find the culprit, we currently know that the pancreas and the endothelium have been found to express Angiotensin-converting enzyme 2 (ACE2) receptors, the main binding site of the virus. To move from bench to bedside, understanding the effects of COVID-19 on metabolism and glucose homeostasis is crucial to prevent and manage complications related to COVID-19 and support recovering patients. In this article we review the potential underlying pathophysiological mechanisms between COVID-19 and glucose dysregulation as well as the effects of antidiabetic treatment in patients with diabetes and COVID-19.

Apremilast Improves Endothelial Glycocalyx Integrity, Vascular and Left Ventricular Myocardial Function in Psoriasis.

The phosphodiesterase 4 inhibitor apremilast is used for the treatment of psoriasis. We investigated the effects of apremilast on endothelial glycocalyx, vascular and left ventricular (LV) myocardial function in psoriasis. One hundred and fifty psoriatic patients were randomized to apremilast (n = 50), anti-tumor necrosis factor-α (etanercept; n = 50), or cyclosporine (n = 50). At baseline and 4 months post-treatment, we measured: (1) Perfused boundary region (PBR), a marker of glycocalyx integrity, in sublingual microvessels with diameter 5-25 µm using a Sidestream Dark Field camera (GlycoCheck). Increased PBR indicates damaged glycocalyx. Functional microvascular density, an index of microvascular perfusion, was also measured. (2) Pulse wave velocity (PWV-Complior) and (3) LV global longitudinal strain (GLS) using speckle-tracking echocardiography. Compared with baseline, PBR5-25 µm decreased only after apremilast (-12% at 4 months, p < 0.05) whereas no significant changes in PBR5-25 µm were observed after etanercept or cyclosporine treatment. Compared with etanercept and cyclosporine, apremilast resulted in a greater increase of functional microvascular density (+14% versus +1% versus -1%) and in a higher reduction of PWV. Apremilast showed a greater increase of GLS (+13.5% versus +7% versus +2%) than etanercept and cyclosporine (p < 0.05). In conclusion, apremilast restores glycocalyx integrity and confers a greater improvement of vascular and myocardial function compared with etanercept or cyclosporine after 4 months.

Association of COVID-19 with impaired endothelial glycocalyx, vascular function and myocardial deformation 4 months after infection.

AIMS: SARS-CoV-2 infection may lead to endothelial and vascular dysfunction. We investigated alterations of arterial stiffness, endothelial coronary and myocardial function markers 4 months after COVID-19 infection. METHODS AND RESULTS: In a case-control prospective study, we included 70 patients 4 months after COVID-19 infection, 70 age- and sex-matched untreated hypertensive patients (positive control) and 70 healthy individuals. We measured (i) perfused boundary region (PBR) of the sublingual arterial microvessels (increased PBR indicates reduced endothelial glycocalyx thickness), (ii) flow-mediated dilatation (FMD), (iii) coronary flow reserve (CFR) by Doppler echocardiography, (iv) pulse wave velocity (PWV), (v) global left and right ventricular longitudinal strain (GLS), and (vi) malondialdehyde (MDA), an oxidative stress marker, thrombomodulin and von Willebrand factor as endothelial biomarkers. COVID-19 patients had similar CFR and FMD as hypertensives (2.48 ± 0.41 vs. 2.58 ± 0.88, P = 0.562, and 5.86 ± 2.82% vs. 5.80 ± 2.07%, P = 0.872, respectively) but lower values than controls (3.42 ± 0.65, P = 0.0135, and 9.06 ± 2.11%, P = 0.002, respectively). Compared to controls, both COVID-19 and hypertensives had greater PBR5-25 (2.07 ± 0.15 µm and 2.07 ± 0.26 µm, P = 0.8 vs. 1.89 ± 0.17 µm, P = 0.001), higher PWV (carotid-femoral PWV 12.09 ± 2.50 vs. 11.92 ± 2.94, P = 0.7 vs. 10.04 ± 1.80 m/s, P = 0.036) and impaired left and right ventricular GLS (-19.50 ± 2.56% vs. -19.23 ± 2.67%, P = 0.864 vs. -21.98 ± 1.51%, P = 0.020 and -16.99 ± 3.17% vs. -18.63 ± 3.20%, P = 0.002 vs. -20.51 ± 2.28%, P < 0.001). MDA and thrombomodulin were higher in COVID-19 patients than both hypertensives and controls (10.67 ± 0.32 vs 1.76 ± 0.03, P = 0.003 vs. 1.01 ± 0.05 nmol/L, P = 0.001 and 3716.63 ± 188.36 vs. 3114.46 ± 179.18 pg/mL, P = 0.017 vs. 2590.02 ± 156.51 pg/mL, P < 0.001). Residual cardiovascular symptoms at 4 months were associated with oxidative stress and endothelial dysfunction markers. CONCLUSIONS: SARS-CoV-2 may cause endothelial and vascular dysfunction linked to impaired cardiac performance 4 months after infection.

Type 1 Diabetes Mellitus in the SARS-CoV-2 Pandemic: Oxidative Stress as a Major Pathophysiological Mechanism Linked to Adverse Clinical Outcomes.

Recent reports have demonstrated the association between type 1 diabetes mellitus (T1DM) and increased morbidity and mortality rates during coronavirus disease (COVID-19) infection, setting a priority of these patients for vaccination. Impaired innate and adaptive immunity observed in T1DM seem to play a major role. Severe, life-threatening COVID-19 disease is characterized by the excessive release of pro-inflammatory cytokines, known as a "cytokine storm". Patients with T1DM present elevated levels of cytokines including interleukin-1a (IL), IL-1ß, IL-2, IL-6 and tumor necrosis factor alpha (TNF-α), suggesting the pre-existence of chronic inflammation, which, in turn, has been considered the major risk factor of adverse COVID-19 outcomes in many cohorts. Even more importantly, oxidative stress is a key player in COVID-19 pathogenesis and determines disease severity. It is well-known that extreme glucose excursions, the prominent feature of T1DM, are a potent mediator of oxidative stress through several pathways including the activation of protein kinase C (PKC) and the increased production of advanced glycation end products (AGEs). Additionally, chronic endothelial dysfunction and the hypercoagulant state observed in T1DM, in combination with the direct damage of endothelial cells by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), may result in endothelial and microcirculation impairment, which contribute to the pathogenesis of acute respiratory syndrome and multi-organ failure. The binding of SARS-CoV-2 to angiotensin converting enzyme 2 (ACE2) receptors in pancreatic b-cells permits the direct destruction of b-cells, which contributes to the development of new-onset diabetes and the induction of diabetic ketoacidosis (DKA) in patients with T1DM. Large clinical studies are required to clarify the exact pathways through which T1DM results in worse COVID-19 outcomes.

An indirect effect of covid-19 on the heart: A case report.

Covid-19 virus has been recognized to develop major cardiac complications. The indirect effect of the virus though, in terms of fear for hospital admissions, constitutes a greater threat. In this case we present a 69-year old male patient who suffered from a myocardial infarction that has not been given the proper attention due to the fear of in-hospital contact with covid patients. The result was the delayed revascularization and eventually the development of heart failure. This case presents the full range of covid-19 affection to the heart and raises the public awareness for not underestimating symptoms suggesting life-threatening conditions.

Tocilizumab improves oxidative stress and endothelial glycocalyx: A mechanism that may explain the effects of biological treatment on COVID-19.

We investigated the effects of tocilizumab on endothelial glycocalyx, a determinant of vascular permeability, and myocardial function in rheumatoid arthritis (RA). Eighty RA patients were randomized to tocilizumab (n = 40) or conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and glucocorticoids (GC) (n = 40) for 3 months. Forty healthy subjects with similar age and sex served as controls. We measured: (a)perfused boundary region (PBR) of the sublingual arterial microvessels (increased PBR indicates reduced glycocalyx thickness), (b)pulse wave velocity (PWV), (c)global LV longitudinal strain (GLS), (d)global work index (GWI) using speckle tracking echocardiography and e)C-reactive protein (CRP), malondialdehyde (MDA) and protein carbonyls (PCs) as oxidative stress markers at baseline and post-treatment. Compared to controls, RA patients had impaired glycocalyx and myocardial deformation markers (P < 0.05). Compared with baseline, tocilizumab reduced PBR(2.14 ± 0.2 versus 1.97 ± 0.2 µm; P < 0.05) while no significant differences were observed post-csDMARDs + GC(P > 0.05). Compared with csDMARDs + GC, tocilizumab achieved a greater increase of GLS, GWI and reduction of MDA, PCs and CRP(P < 0.05). The percent improvement of glycocalyx thickness (PBR) was associated with the percent decrease of PWV, MDA, PCs and the percent improvement of GLS and GWI(P < 0.05). Tocilizumab improves endothelial function leading to a greater increase of effective myocardial work than csDMARDs + GC through a profound reduction of inflammatory burden and oxidative stress. This mechanism may explain the effects of tocilizumab on COVID-19. CLINICAL TRIAL REGISTRATION: url: https://www.clinicaltrials.gov. Unique identifier: NCT03288584.

The Dual Role of Echocardiography in the Diagnosis of Acute Cardiac Complications and Treatment Monitoring for Coronavirus Disease 2019 (COVID-19).

The Coronavirus Disease 2019 (COVID-19) pandemic, being caused by an easily and rapidly spreading novel betacoronavirus, has created a state of emergency for people, the scientific community, healthcare systems and states, while the global financial consequences are still unfolding. Cardiovascular complications have been reported for COVID-19-infected patients and are associated with a worse prognosis. ECG and biomarkers may raise suspicion of cardiac involvement. However, transthoracic echocardiography is a fast and reliable bedside method to establish the diagnosis of cardiac complications, including acute coronary syndromes, pericarditis, myocarditis, and pulmonary embolism. Early detection of cardiac dysfunction by speckle tracking echocardiography during off-line analysis may be used to identify a high-risk population for development of heart failure in the acute setting. Precautionary measures are mandatory for operators and equipment to avoid viral dispersion. No specific treatment is yet available for severe acute respiratory syndrome coronavirus 2 (SARS-CoV 2), and a variety of antiviral, immune-modifying, and antioxidant agents are therefore under intense investigation. Echocardiography, including assessment of myocardial deformation, may provide a useful tool to monitor the effects of the various treatment regimens on cardiac function both acutely and in the midterm.

Obesity and COVID-19: immune and metabolic derangement as a possible link to adverse clinical outcomes.

Recent reports have shown a strong association between obesity and the severity of COVID-19 infection, even in the absence of other comorbidities. After infecting the host cells, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may cause a hyperinflammatory reaction through the excessive release of cytokines, a condition known as "cytokine storm," while inducing lymphopenia and a disrupted immune response. Obesity is associated with chronic low-grade inflammation and immune dysregulation, but the exact mechanisms through which it exacerbates COVID-19 infection are not fully clarified. The production of increased amounts of cytokines such as TNFα, IL-1, IL-6, and monocyte chemoattractant protein (MCP-1) lead to oxidative stress and defective function of innate and adaptive immunity, whereas the activation of NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome seems to play a crucial role in the pathogenesis of the infection. Endothelial dysfunction and arterial stiffness could favor the recently discovered infection of the endothelium by SARS-CoV-2, whereas alterations in cardiac structure and function and the prothrombotic microenvironment in obesity could provide a link for the increased cardiovascular events in these patients. The successful use of anti-inflammatory agents such as IL-1 and IL-6 blockers in similar hyperinflammatory settings, like that of rheumatoid arthritis, has triggered the discussion of whether such agents could be administrated in selected patients with COVID-19 disease.