Long COVID: The Nature of Thrombotic Sequelae Determines the Necessity of Early Anticoagulation

Molecular cross-talk between long COVID-19 and Alzheimer's disease

The long COVID (coronavirus disease), a multisystemic condition following severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, is one of the widespread problems. Some of its symptoms affect the nervous system and resemble symptoms of Alzheimer's disease (AD)-a neurodegenerative condition caused by the accumulation of amyloid beta and hyperphosphorylation of tau proteins. Multiple studies have found dependence between these two conditions. Patients with Alzheimer's disease have a greater risk of SARS-CoV-2 infection due to increased levels of angiotensin-converting enzyme 2 (ACE2), and the infection itself promotes amyloid beta generation which enhances the risk of AD. Also, the molecular pathways are alike-misregulations in folate-mediated one-carbon metabolism, a deficit of Cq10, and disease-associated microglia. Medical imaging in both of these diseases shows a decrease in the volume of gray matter, global brain size reduction, and hypometabolism in the parahippocampal gyrus, thalamus, and cingulate cortex. In some studies, a similar approach to applied medication can be seen, including the use of amino adamantanes and phenolic compounds of rosemary. The significance of these connections and their possible application in medical practice still needs further study but there is a possibility that they will help to better understand long COVID.

The Role of Heparin in Postural Orthostatic Tachycardia Syndrome and Other Post-Acute Sequelae of COVID-19

The therapeutic management and short-term consequences of the coronavirus disease 2019 (COVID-19) are well known. However, COVID-19 post-acute sequelae are less known and represent a public health problem worldwide. Patients with COVID-19 who present post-acute sequelae may display immune dysregulation, a procoagulant state, and persistent microvascular endotheliopathy that could trigger microvascular thrombosis. These elements have also been implicated in the physiopathology of postural orthostatic tachycardia syndrome, a frequent sequela in post-COVID-19 patients. These mechanisms, directly associated with post-acute sequelae, might determine the thrombotic consequences of COVID-19 and the need for early anticoagulation therapy. In this context, heparin has several potential benefits, including immunomodulatory, anticoagulant, antiviral, pro-endothelial, and vascular effects, that could be helpful in the treatment of COVID-19 post-acute sequelae. In this article, we review the evidence surrounding the post-acute sequelae of COVID-19 and the potential benefits of the use of heparin, with a special focus on the treatment of postural orthostatic tachycardia syndrome.

Long COVID-ACOEM Guidance Statement

ABSTRACT

Persistent symptoms are common after acute COVID-19, often referred to as long COVID. Long COVID may affect the ability to perform activities of daily living, including work. Long COVID occurs more frequently in those with severe acute COVID-19. This guidance statement reviews the pathophysiology of severe acute COVID-19 and long COVID and provides pragmatic approaches to long COVID symptoms, syndromes, and conditions in the occupational setting. Disability laws and workers' compensation are also addressed.

The knowns and unknowns of long COVID-19: from mechanisms to therapeutical approaches

The coronavirus disease 2019 (COVID-19) pandemic caused by SARS-CoV-2 has been defined as the greatest global health and socioeconomic crisis of modern times. While most people recover after being infected with the virus, a significant proportion of them continue to experience health issues weeks, months and even years after acute infection with SARS-CoV-2. This persistence of clinical symptoms in infected individuals for at least three months after the onset of the disease or the emergence of new symptoms lasting more than two months, without any other explanation and alternative diagnosis have been named long COVID, long-haul COVID, post-COVID-19 conditions, chronic COVID, or post-acute sequelae of SARS-CoV-2 (PASC). Long COVID has been characterized as a constellation of symptoms and disorders that vary widely in their manifestations. Further, the mechanisms underlying long COVID are not fully understood, which hamper efficient treatment options. This review describes predictors and the most common symptoms related to long COVID's effects on the central and peripheral nervous system and other organs and tissues. Furthermore, the transcriptional markers, molecular signaling pathways and risk factors for long COVID, such as sex, age, pre-existing condition, hospitalization during acute phase of COVID-19, vaccination, and lifestyle are presented. Finally, recommendations for patient rehabilitation and disease management, as well as alternative therapeutical approaches to long COVID sequelae are discussed. Understanding the complexity of this disease, its symptoms across multiple organ systems and overlapping pathologies and its possible mechanisms are paramount in developing diagnostic tools and treatments.

Increased Levels of Inflammatory and Endothelial Biomarkers in Blood of Long COVID Patients Point to Thrombotic Endothelialitis

The prevailing hypotheses for the persistent symptoms of Long COVID have been narrowed down to immune dysregulation and autoantibodies, widespread organ damage, viral persistence, and fibrinaloid microclots (entrapping numerous inflammatory molecules) together with platelet hyperactivation. Here we demonstrate significantly increased concentrations of von Willebrand factor (VWF), platelet factor 4 (PF4), serum amyloid A (SAA), α-2 antiplasmin (α-2AP), endothelial-leukocyte adhesion molecule 1 (E-selectin), and platelet endothelial cell adhesion molecule (PECAM-1) in the soluble part of the blood. It was noteworthy that the mean level of α-2 antiplasmin exceeded the upper limit of the laboratory reference range in Long COVID patients, and the other 5 were significantly elevated in Long COVID patients as compared to the controls. This is alarming if we take into consideration that a significant amount of the total burden of these inflammatory molecules has previously been shown to be entrapped inside fibrinolysis-resistant microclots (thus decreasing the apparent level of the soluble molecules). We conclude that presence of microclotting, together with relatively high levels of six biomarkers known to be key drivers of endothelial and clotting pathology, points to thrombotic endothelialitis as a key pathological process in Long COVID.

Pathophysiological, immunological, and inflammatory features of long COVID

The COVID-19 pandemic continues to cause severe global disruption, resulting in significant excess mortality, overwhelming healthcare systems, and imposing substantial social and economic burdens on nations. While most of the attention and therapeutic efforts have concentrated on the acute phase of the disease, a notable proportion of survivors experience persistent symptoms post-infection clearance. This diverse set of symptoms, loosely categorized as long COVID, presents a potential additional public health crisis. It is estimated that 1 in 5 COVID-19 survivors exhibit clinical manifestations consistent with long COVID. Despite this prevalence, the mechanisms and pathophysiology of long COVID remain poorly understood. Alarmingly, evidence suggests that a significant proportion of cases within this clinical condition develop debilitating or disabling symptoms. Hence, urgent priority should be given to further studies on this condition to equip global public health systems for its management. This review provides an overview of available information on this emerging clinical condition, focusing on the affected individuals' epidemiology, pathophysiological mechanisms, and immunological and inflammatory profiles.

Post-COVID-19 thrombotic sequelae: The potential role of persistent platelet hyperactivity

Postacute COVID-19 sequelae affect millions of individuals, and active research into the pathophysiological mechanisms and potential treatments is underway. The report by Nara and colleagues shows persistent platelet hyperactivity in the chronic phase of the infection, suggesting a possible role of platelets in post-COVID-19 complications and, consequently, a possible therapeutic target. Commentary on: Nara et al. Prolonged platelet hyperactivity after COVID-19 infection. Br J Haematol 2024;204:492-496.

The Multisystem Impact of Long COVID: A Comprehensive Review

(1) Background: COVID-19 was responsible for the latest pandemic, shaking and reshaping healthcare systems worldwide. Its late clinical manifestations make it linger in medical memory as a debilitating illness over extended periods. (2) Methods: the recent literature was systematically analyzed to categorize and examine the symptomatology and pathophysiology of Long COVID across various bodily systems, including pulmonary, cardiovascular, gastrointestinal, neuropsychiatric, dermatological, renal, hematological, and endocrinological aspects. (3) Results: The review outlines the diverse clinical manifestations of Long COVID across multiple systems, emphasizing its complexity and challenges in diagnosis and treatment. Factors such as pre-existing conditions, initial COVID-19 severity, vaccination status, gender, and age were identified as influential in the manifestation and persistence of Long COVID symptoms. This condition is highlighted as a debilitating disease capable of enduring over an extended period and presenting new symptoms over time. (4) Conclusions: Long COVID emerges as a condition with intricate multi-systemic involvement, complicating its diagnosis and treatment. The findings underscore the necessity for a nuanced understanding of its diverse manifestations to effectively manage and address the evolving nature of this condition over time.

Persistent complement dysregulation with signs of thromboinflammation in active Long Covid

Long Covid is a debilitating condition of unknown etiology. We performed multimodal proteomics analyses of blood serum from COVID-19 patients followed up to 12 months after confirmed severe acute respiratory syndrome coronavirus 2 infection. Analysis of >6500 proteins in 268 longitudinal samples revealed dysregulated activation of the complement system, an innate immune protection and homeostasis mechanism, in individuals experiencing Long Covid. Thus, active Long Covid was characterized by terminal complement system dysregulation and ongoing activation of the alternative and classical complement pathways, the latter associated with increased antibody titers against several herpesviruses possibly stimulating this pathway. Moreover, markers of hemolysis, tissue injury, platelet activation, and monocyte-platelet aggregates were increased in Long Covid. Machine learning confirmed complement and thromboinflammatory proteins as top biomarkers, warranting diagnostic and therapeutic interrogation of these systems.

AC-73 and Syrosingopine Inhibit SARS-CoV-2 Entry into Megakaryocytes by Targeting CD147 and MCT4

Coagulation disorders are described in COVID-19 and long COVID patients. In particular, SARS-CoV-2 infection in megakaryocytes, which are precursors of platelets involved in thrombotic events in COVID-19, long COVID and, in rare cases, in vaccinated individuals, requires further investigation, particularly with the emergence of new SARS-CoV-2 variants. CD147, involved in the regulation of inflammation and required to fight virus infection, can facilitate SARS-CoV-2 entry into megakaryocytes. MCT4, a co-binding protein of CD147 and a key player in the glycolytic metabolism, could also play a role in SARS-CoV-2 infection. Here, we investigated the susceptibility of megakaryocytes to SARS-CoV-2 infection via CD147 and MCT4. We performed infection of Dami cells and human CD34+ hematopoietic progenitor cells induced to megakaryocytic differentiation with SARS-CoV-2 pseudovirus in the presence of AC-73 and syrosingopine, respective inhibitors of CD147 and MCT4 and inducers of autophagy, a process essential in megakaryocyte differentiation. Both AC-73 and syrosingopine enhance autophagy during differentiation but only AC-73 enhances megakaryocytic maturation. Importantly, we found that AC-73 or syrosingopine significantly inhibits SARS-CoV-2 infection of megakaryocytes. Altogether, our data indicate AC-73 and syrosingopine as inhibitors of SARS-CoV-2 infection via CD147 and MCT4 that can be used to prevent SARS-CoV-2 binding and entry into megakaryocytes, which are precursors of platelets involved in COVID-19-associated coagulopathy.

Serum from COVID-19 patients promotes endothelial cell dysfunction through protease-activated receptor 2

BACKGROUND

Endothelial dysfunction plays a central role in the pathophysiology of COVID-19 and is closely linked to the severity and mortality of the disease. The inflammatory response to SARS-CoV-2 infection can alter the capacity of the endothelium to regulate vascular tone, immune responses, and the balance between anti-thrombotic and pro-thrombotic properties. However, the specific endothelial pathways altered during COVID-19 still need to be fully understood.

OBJECTIVE

In this study, we sought to identify molecular changes in endothelial cells induced by circulating factors characteristic of COVID-19.

METHODS AND RESULTS

To this aim, we cultured endothelial cells with sera from patients with COVID-19 or non-COVID-19 pneumonia. Through transcriptomic analysis, we were able to identify a distinctive endothelial phenotype that is induced by sera from COVID-19 patients. We confirmed and expanded this observation in vitro by showing that COVID-19 serum alters functional properties of endothelial cells leading to increased apoptosis, loss of barrier integrity, and hypercoagulability. Furthermore, we demonstrated that these endothelial dysfunctions are mediated by protease-activated receptor 2 (PAR-2), as predicted by transcriptome network analysis validated by in vitro functional assays.

CONCLUSION

Our findings provide the rationale for further studies to evaluate whether targeting PAR-2 may be a clinically effective strategy to counteract endothelial dysfunction in COVID-19.

Beyond the Acute Phase: Long-Term Impact of COVID-19 on Functional Capacity and Prothrombotic Risk-A Pilot Study

Background and Objectives: Assessment of the prothrombotic, proinflammatory, and functional status of a cohort of COVID-19 patients at least two years after the acute infection to identify parameters with potential therapeutic and prognostic value. Materials and Methods: We conducted a retrospective, descriptive study that included 117 consecutive patients admitted to Iasi Pulmonary Rehabilitation Clinic for reassessment and a rehabilitation program at least two years after a COVID-19 infection. The cohort was divided into two groups based on the presence (n = 49) or absence (n = 68) of pulmonary fibrosis, documented through high-resolution computer tomography. Results: The cohort comprises 117 patients, 69.23% females, with a mean age of 65.74 ± 10.19 years and abnormal body mass index (31.42 ± 5.71 kg/m2). Patients with pulmonary fibrosis have significantly higher levels of C-reactive protein (CRP) (p < 0.05), WBC (7.45 ± 7.86/mm3 vs. 9.18 ± 17.24/mm3, p = 0.053), neutrophils (4.68 ± 7.88/mm3 vs. 9.07 ± 17.44/mm3, p < 0.05), mean platelet volume (MPV) (7.22 ± 0.93 vs. 10.25 ± 0.86 fL, p < 0.05), lactate dehydrogenase (p < 0.05), and D-dimers (p < 0.05), but not ferritin (p = 0.470), reflecting the chronic proinflammatory and prothrombotic status. Additionally, patients with associated pulmonary fibrosis had a higher mean heart rate (p < 0.05) and corrected QT interval (p < 0.05). D-dimers were strongly and negatively correlated with diffusion capacity corrected for hemoglobin (DLCO corr), and ROC analysis showed that the persistence of high D-dimers values is a predictor for low DLCO values (ROC analysis: area under the curve of 0.772, p < 0.001). The results of pulmonary function tests (spirometry, body plethysmography) and the 6-minute walk test demonstrated no significant difference between groups, without notable impairment within either group. Conclusions: Patients with COVID-19-related pulmonary fibrosis have a persistent long-term proinflammatory, prothrombotic status, despite the functional recovery. The persistence of elevated D-dimer levels could emerge as a predictive factor associated with impaired DLCO.

All eyes on PCS: analysis of the retinal microvasculature in patients with post-COVID syndrome-study protocol of a 1 year prospective case-control study

Since widespread vaccination against COVID-19, the development of effective antiviral drugs, and the decreasing number of patients with COVID-19 in intensive care, the risk from SARS-CoV-2 infection appears less threatening. However, studies show that a significant number of patients suffer from long-term sequelae, even months after SARS-CoV-2 infection. The so-called post-COVID syndrome (PCS) often presents a diagnostic and treatment challenge for physicians. This study protocol describes the "All Eyes on PCS" study, which aims to investigate the retinal microvasculature in PCS patients and COVID-19-recovered patients to provide new insights into the pathophysiology of PCS. "All Eyes on PCS" is a prospective, case-control study with the primary objective of detecting endothelial dysfunction (ED) in patients with PCS. Therefore, we intend to recruit patients with PCS, fully SARS-CoV-2-infection-recovered (CR) participants, and SARS-CoV-2-infection-naïve (CN) participants. Baseline measurements will include: (1) patient-specific characteristics, (2) biochemistry, (3) retinal vessel analysis (RVA), (4) survey questionnaires as patient-reported outcomes measurements (PROMs), (5) optical coherence tomography (OCT), OCT angiography (OCTA), and adaptive optics (AO), (6) blood pressure recordings, (7) handgrip strength test. After 6 months, baseline measurements will be repeated in the PCS cohort, and after 1 year, a telephone query will be conducted to assess residual symptoms and treatment needs. The aim of this study is to gain insight into the pathophysiology of PCS and to provide an objective biomarker for diagnosis and treatment, while also creating a comprehensive clinical database of PCS patients.ClinicalTrials.gov Identifier: NCT05635552; Date: 2.12.2022.

Dihydroartemisinin-Ursodeoxycholic Bile Acid Hybrids in the Fight against SARS-CoV-2

Here, we propose the molecular hybridization of dihydroartemisinin (DHA) and ursodeoxycholic bile acid (UDCA), approved drugs, for the preparation of antiviral agents against SARS-CoV-2. DHA and UDCA were selected on the basis of their recently demonstrated in vitro activity against SARS-CoV-2. A selection of DHA-UDCA-based hybrids obtained by varying the nature of the linkage and the bile acid conjugation point as well as unconjugated DHA and UDCA were tested in vitro for cytotoxicity and anti-SARS-CoV-2 activity on Vero E6 and Calu-3 human lung cells. The hybrid DHA-t-UDCMe, obtained by conjugation via click chemistry on a gram scale, was identified as a potential candidate for SARS-CoV-2 infection treatment due to significant reduction of viral replication, possibly involving ACE2 downregulation, no cytotoxicity, and chemical stability.

Risk Factors for Long COVID in Older Adults

As time has passed following the COVID-19 pandemic, individuals infected with SARS-CoV-2 have gradually exhibited a variety of symptoms associated with long COVID in the postacute phase of infection. Simultaneously, in many countries worldwide, the process of population aging has been accelerating. Within this context, the elderly population has not only become susceptible and high-risk during the acute phase of COVID-19 but also has considerable risks when confronting long COVID. Elderly individuals possess specific immunological backgrounds, and during the process of aging, their immune systems can enter a state known as "immunosenescence". This further exacerbates "inflammaging" and the development of various comorbidities in elderly individuals, rendering them more susceptible to long COVID. Additionally, long COVID can inflict both physical and mental harm upon elderly people, thereby reducing their overall quality of life. Consequently, the impact of long COVID on elderly people should not be underestimated. This review seeks to summarize the infection characteristics and intrinsic factors of older adults during the COVID-19 pandemic, with a focus on the physical and mental impact of long COVID. Additionally, it aims to explore potential strategies to mitigate the risk of long COVID or other emerging infectious diseases among older adults in the future.

What Role Does Microthrombosis Play in Long COVID?

Soon after the outbreak of coronavirus disease 2019 (COVID-19), unexplained sustained fatigue, cognitive disturbance, and muscle ache/weakness were reported in patients who had recovered from acute COVID-19 infection. This abnormal condition has been recognized as "long COVID (postacute sequelae of COVID-19 [PASC])" with a prevalence estimated to be from 10 to 20% of convalescent patients. Although the pathophysiology of PASC has been studied, the exact mechanism remains obscure. Microclots in circulation can represent one of the possible causes of PASC. Although hypercoagulability and thrombosis are critical mechanisms of acute COVID-19, recent studies have reported that thromboinflammation continues in some patients, even after the virus has cleared. Viral spike proteins and RNA can be detected months after patients have recovered, findings that may be responsible for persistent thromboinflammation and the development of microclots. Despite this theory, long-term results of anticoagulation, antiplatelet therapy, and vascular endothelial protection are inconsistent, and could not always show beneficial treatment effects. In summary, PASC reflects a heterogeneous condition, and microclots cannot explain all the presenting symptoms. After clarification of the pathomechanisms of each symptom, a symptom- or biomarker-based stratified approach should be considered for future studies.

Epstein-Barr virus-acquired immunodeficiency in myalgic encephalomyelitis-Is it present in long COVID?

Both myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS) and long COVID (LC) are characterized by similar immunological alterations, persistence of chronic viral infection, autoimmunity, chronic inflammatory state, viral reactivation, hypocortisolism, and microclot formation. They also present with similar symptoms such as asthenia, exercise intolerance, sleep disorders, cognitive dysfunction, and neurological and gastrointestinal complaints. In addition, both pathologies present Epstein-Barr virus (EBV) reactivation, indicating the possibility of this virus being the link between both pathologies. Therefore, we propose that latency and recurrent EBV reactivation could generate an acquired immunodeficiency syndrome in three steps: first, an acquired EBV immunodeficiency develops in individuals with "weak" EBV HLA-II haplotypes, which prevents the control of latency I cells. Second, ectopic lymphoid structures with EBV latency form in different tissues (including the CNS), promoting inflammatory responses and further impairment of cell-mediated immunity. Finally, immune exhaustion occurs due to chronic exposure to viral antigens, with consolidation of the disease. In the case of LC, prior to the first step, there is the possibility of previous SARS-CoV-2 infection in individuals with "weak" HLA-II haplotypes against this virus and/or EBV.

Pulmonary embolism following an undiagnosed Paget-Schroetter syndrome: a case report and review of the literature

Paget-Schroetter Syndrome (PSS) is a rare condition characterized by spontaneous thrombosis of the axillary-subclavian vein that occurs predominantly in young athletes engaged in repetitive overhead upper extremity motion, for instance, weightlifting, swimming, baseball, and tennis. PSS is usually a consequence of chronic repetitive microtrauma to the vein intima due to compression of the axillary-subclavian vein by the thoracic outlet structures. This chronic injury can then be acutely exacerbated by vigorous exercise done over a brief period, accelerating thrombus formation. Lack of PSS awareness leads to underdiagnosis, misdiagnosis, or late diagnosis, which can pose life-threatening risks to patients, including pulmonary embolism (PE) and recurrent thrombosis. This case report of a 20-year-old male college athlete exposes a PE caused by PSS, potentially worsened by a delay in diagnosis. Early suspicion and proper management are crucial for optimizing long-term outcomes and facilitating limb rehabilitation. The recommended approach involves early catheter-directed thrombolysis followed by thoracic outlet decompression.

Viral anti-inflammatory serpin reduces immuno-coagulopathic pathology in SARS-CoV-2 mouse models of infection

SARS-CoV-2 acute respiratory distress syndrome (ARDS) induces uncontrolled lung inflammation and coagulopathy with high mortality. Anti-viral drugs and monoclonal antibodies reduce early COVID-19 severity, but treatments for late-stage immuno-thrombotic syndromes and long COVID are limited. Serine protease inhibitors (SERPINS) regulate activated proteases. The myxoma virus-derived Serp-1 protein is a secreted immunomodulatory serpin that targets activated thrombotic, thrombolytic, and complement proteases as a self-defense strategy to combat clearance. Serp-1 is effective in multiple animal models of inflammatory lung disease and vasculitis. Here, we describe systemic treatment with purified PEGylated Serp-1 as a therapy for immuno-coagulopathic complications during ARDS. Treatment with PEGSerp-1 in two mouse-adapted SARS-CoV-2 models in C57Bl/6 and BALB/c mice reduced lung and heart inflammation, with improved outcomes. PEGSerp-1 significantly reduced M1 macrophages in the lung and heart by modifying urokinase-type plasminogen activator receptor (uPAR), thrombotic proteases, and complement membrane attack complex (MAC). Sequential changes in gene expression for uPAR and serpins (complement and plasminogen inhibitors) were observed. PEGSerp-1 is a highly effective immune-modulator with therapeutic potential for severe viral ARDS, immuno-coagulopathic responses, and Long COVID.

The Potential Role of Hypothalamic Phospholipid Liposomes in the Supportive Therapy of Some Manifestations of Post-COVID-19 Condition: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Brain Fog

Post-COVID-19 condition (commonly known as Long COVID) is a heterogeneous clinical condition in which Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and brain fog stand out among the different clinical symptoms and syndromes. Cerebral metabolic alterations and neuroendocrine disorders seem to constitute an important part of the pathophysiology of Post-COVID-19 condition (PCC). Given the substantial lack of specific drugs and effective therapeutic strategies, hypothalamic phospholipid liposomes, which have been on the market for several years as adjuvant therapy for cerebral metabolic alterations resulting from neuroendocrine disorders, might represent a potential option in an overall therapeutic strategy that aims to control PCC-associated symptoms and syndromes. Their pharmacological mechanisms and clinical effects strongly support their potential effectiveness in PCC. Our initial clinical experience seems to corroborate this rationale. Further controlled clinical research is warranted in order to verify this hypothesis.

Role of Endothelium in Cardiovascular Sequelae of Long COVID

The global action against coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2 infection, shed light on endothelial dysfunction. Although SARS-CoV-2 primarily affects the pulmonary system, multiple studies have documented pan-vascular involvement in COVID-19. The virus is able to penetrate the endothelial barrier, damaging it directly or indirectly and causing endotheliitis and multi-organ injury. Several mechanisms cooperate to development of endothelial dysfunction, including endothelial cell injury and pyroptosis, hyperinflammation and cytokine storm syndrome, oxidative stress and reduced nitric oxide bioavailability, glycocalyx disruption, hypercoagulability, and thrombosis. After acute-phase infection, some patients reported signs and symptoms of a systemic disorder known as long COVID, in which a broad range of cardiovascular (CV) disorders emerged. To date, the exact pathophysiology of long COVID remains unclear: in addition to the persistence of acute-phase infection mechanisms, specific pathways of CV damage have been postulated, such as persistent viral reservoirs in the heart or an autoimmune response to cardiac antigens through molecular mimicry. The aim of this review is to provide an overview of the main molecular patterns of enduring endothelial activation following SARS-CoV-2 infection and to offer the latest summary of CV complications in long COVID.

Hematological alterations associated with long COVID-19

Long COVID-19 is a condition characterized by persistent symptoms lasting beyond the acute phase of COVID-19. Long COVID-19 produces diverse symptomatology and can impact organs and systems, including the hematological system. Several studies have reported, in COVID-19 patients, hematological abnormalities. Most of these alterations are associated with a higher risk of severe disease and poor outcomes. This literature review identified studies reporting hematological parameters in individuals with Long COVID-19. Findings suggest that Long COVID-19 is associated with a range of sustained hematological alterations, including alterations in red blood cells, anemia, lymphopenia, and elevated levels of inflammatory markers such as ferritin, D-dimer, and IL-6. These alterations may contribute to a better understanding of the pathophysiology of Long COVID-19 and its associated symptoms. However, further research is needed to elucidate the underlying mechanisms and potential treatments for these hematological changes in individuals with Long COVID-19.

Long COVID: An approach to clinical assessment and management in primary care

Long COVID is an emerging public health threat, following swiftly behind the surges of acute infection over the course of the COVID-19 pandemic. It is estimated that there are already approximately 100 million people suffering from Long COVID globally, 0.5 million of whom are South African, and for whom our incomplete understanding of the condition has forestalled appropriate diagnosis and clinical care. There are several leading postulates for the complex, multi-mechanistic pathogenesis of Long COVID. Patients with Long COVID may present with a diversity of clinical phenotypes, often with significant overlap, which may exhibit temporal heterogeneity and evolution. Post-acute care follow-up, targeted screening, diagnosis, a broad initial assessment and more directed subsequent assessments are necessary at the primary care level. Symptomatic treatment, self-management and rehabilitation are the mainstays of clinical care for Long COVID. However, evidence-based pharmacological interventions for the prevention and treatment of Long COVID are beginning to emerge. This article presents a rational approach for assessing and managing patients with Long COVID in the primary care setting.

Biological mechanisms underpinning the development of long COVID

As COVID-19 evolves from a pandemic to an endemic disease, the already staggering number of people that have been or will be infected with SARS-CoV-2 is only destined to increase, and the majority of humanity will be infected. It is well understood that COVID-19, like many other viral infections, leaves a significant fraction of the infected with prolonged consequences. Continued high number of SARS-CoV-2 infections, viral evolution with escape from post-infection and vaccinal immunity, and reinfections heighten the potential impact of Long COVID. Hence, the impact of COVID-19 on human health will be seen for years to come until more effective vaccines and pharmaceutical treatments become available. To that effect, it is imperative that the mechanisms underlying the clinical manifestations of Long COVID be elucidated. In this article, we provide an in-depth analysis of the evidence on several potential mechanisms of Long COVID and discuss their relevance to its pathogenesis.

Metabolic alterations upon SARS-CoV-2 infection and potential therapeutic targets against coronavirus infection

The coronavirus disease 2019 (COVID-19) caused by coronavirus SARS-CoV-2 infection has become a global pandemic due to the high viral transmissibility and pathogenesis, bringing enormous burden to our society. Most patients infected by SARS-CoV-2 are asymptomatic or have mild symptoms. Although only a small proportion of patients progressed to severe COVID-19 with symptoms including acute respiratory distress syndrome (ARDS), disseminated coagulopathy, and cardiovascular disorders, severe COVID-19 is accompanied by high mortality rates with near 7 million deaths. Nowadays, effective therapeutic patterns for severe COVID-19 are still lacking. It has been extensively reported that host metabolism plays essential roles in various physiological processes during virus infection. Many viruses manipulate host metabolism to avoid immunity, facilitate their own replication, or to initiate pathological response. Targeting the interaction between SARS-CoV-2 and host metabolism holds promise for developing therapeutic strategies. In this review, we summarize and discuss recent studies dedicated to uncovering the role of host metabolism during the life cycle of SARS-CoV-2 in aspects of entry, replication, assembly, and pathogenesis with an emphasis on glucose metabolism and lipid metabolism. Microbiota and long COVID-19 are also discussed. Ultimately, we recapitulate metabolism-modulating drugs repurposed for COVID-19 including statins, ASM inhibitors, NSAIDs, Montelukast, omega-3 fatty acids, 2-DG, and metformin.

Low avidity circulating SARS-CoV-2 reactive CD8+ T cells with proinflammatory TEMRA phenotype are associated with post-acute sequelae of COVID-19

The role of adaptive SARS-CoV-2 specific immunity in post-acute sequelae of COVID-19 (PASC) is not well explored, although a growing population of convalescent COVID-19 patients with manifestation of PASC is observed. We analyzed the SARS-CoV-2-specific immune response, via pseudovirus neutralizing assay and multiparametric flow cytometry in 40 post-acute sequelae of COVID-19 patients with non-specific PASC manifestation and 15 COVID-19 convalescent healthy donors. Although frequencies of SARS-CoV-2-reactive CD4+ T cells were similar between the studied cohorts, a stronger SARS-CoV-2 reactive CD8+ T cell response, characterized by IFNγ production and predominant T_EMRA phenotype but low functional TCR avidity was detected in PASC patients compared to controls. Of interest, high avidity SARS-CoV-2-reactive CD4+ and CD8+ T cells were comparable between the groups demonstrating sufficient cellular antiviral response in PASC. In line with the cellular immunity, neutralizing capacity in PASC patients was not inferior compared to controls. In conclusion, our data suggest that PASC may be driven by an inflammatory response triggered by an expanded population of low avidity SARS-CoV-2 reactive pro-inflammatory CD8+ T cells. These pro-inflammatory T cells with TEMRA phenotype are known to be activated by a low or even without TCR stimulation and lead to a tissue damage. Further studies including animal models are required for a better understanding of underlying immunopathogensis. Summary: A CD8+ driven persistent inflammatory response triggered by SARS-CoV-2 may be responsible for the observed sequelae in PASC patients.

Prophylactic rivaroxaban in the early post-discharge period reduces the rates of hospitalization for atrial fibrillation and incidence of sudden cardiac death during long-term follow-up in hospitalized COVID-19 survivors

Introduction: While acute Coronavirus disease 2019 (COVID-19) affects the cardiovascular (CV) system according to recent data, an increased CV risk has been reported also during long-term follow-up (FU). In addition to other CV pathologies in COVID-19 survivors, an enhanced risk for arrhythmic events and sudden cardiac death (SCD) has been observed. While recommendations on post-discharge thromboprophylaxis are conflicting in this population, prophylactic short-term rivaroxaban therapy after hospital discharge showed promising results. However, the impact of this regimen on the incidence of cardiac arrhythmias has not been evaluated to date. Methods: To investigate the efficacy of this therapy, we conducted a single center, retrospective analysis of 1804 consecutive, hospitalized COVID-19 survivors between April and December 2020. Patients received either a 30-day post-discharge thromboprophylaxis treatment regimen using rivaroxaban 10 mg every day (QD) (Rivaroxaban group (Riva); n = 996) or no thromboprophylaxis (Control group (Ctrl); n = 808). Hospitalization for new atrial fibrillation (AF), new higher-degree Atrioventricular-block (AVB) as well as incidence of SCD were investigated in 12-month FU [FU: 347 (310/449) days]. Results: No differences in baseline characteristics (Ctrl vs Riva: age: 59.0 (48.9/66.8) vs 57 (46.5/64.9) years, p = n.s.; male: 41.5% vs 43.7%, p = n.s.) and in the history of relevant CV-disease were observed between the two groups. While hospitalizations for AVB were not reported in either group, relevant rates of hospitalizations for new AF (0.99%, n = 8/808) as well as a high rate of SCD events (2.35%, n = 19/808) were seen in the Ctrl. These cardiac events were attenuated by early post-discharge prophylactic rivaroxaban therapy (AF: n = 2/996, 0.20%, p = 0.026 and SCD: n = 3/996, 0.30%, p < 0.001) which was also observed after applying a logistic regression model for propensity score matching (AF: χ ²-statistics = 6.45, p = 0.013 and SCD: χ ²-statistics = 9.33, p = 0.002). Of note, no major bleeding complications were observed in either group. Conclusion: Atrial arrhythmic and SCD events are present during the first 12 months after hospitalization for COVID-19. Extended prophylactic Rivaroxaban therapy after hospital discharge could reduce new onset of AF and SCD in hospitalized COVID-19 survivors.

Intrinsic factors behind long-COVID: I. Prevalence of the extracellular vesicles

It can be argued that the severity of COVID-19 has decreased in many countries. This could be a result of the broad coverage of the population by vaccination campaigns, which often reached an almost compulsory status in many places. Furthermore, significant roles were played by the multiple mutations in the body of the virus, which led to the emergence of several new SARS-CoV-2 variants with enhanced infectivity but dramatically reduced pathogenicity. However, the challenges associated with the development of various side effects and their persistence for long periods exceeding 20 months as a result of the SARS-CoV-2 infection, or taking available vaccines against it, are spreading horizontally and vertically in number and repercussions. For example, the World Health Organization announced that there are more than 17 million registered cases of long-COVID (also known as post-COVID syndrome) in the European Union countries alone. Furthermore, by using the PubMed search engine, one can find that more than 10 000 articles have been published focusing exclusively on long-COVID. In light of these enormous and ever-increasing numbers of cases and published articles, most of which are descriptive of the various long-COVID symptoms, the need to know the reasons behind this phenomenon raises several important questions. Is long-COVID caused by the continued presence of the virus or one/several of its components in the recovering individual body for long periods of time, which urges the body to respond in a way that leads to long-COVID development? Or are there some latent and limited reasons related to the recovering patients themselves? Or is it a sum of both? Many observations support a positive answer to the first question, whereas others back the second question but typically without releasing a fundamental reason/signal behind it. Whatever the answer is, it seems that the real reasons behind this widespread phenomenon remain unclear. This report opens a series of articles, in which we will try to shed light on the underlying causes that could be behind the long-COVID phenomenon.

Myocardial extracellular volume assessment at CT in hospitalized COVID-19 patients with regards to pulmonary embolism

Purpose

To evaluate myocardial status through the assessment of extracellular volume (ECV) calculated at computed tomography (CT) in patients hospitalized for novel coronavirus disease (COVID-19), with regards to the presence of pulmonary embolism (PE) as a risk factor for cardiac dysfunction.

Method

Hospitalized patients with COVID-19 who underwent contrast-enhanced CT at our institution were retrospectively included in this study and grouped with regards to the presence of PE. Unenhanced and portal venous phase scans were used to calculate ECV by placing regions of interest in the myocardial septum and left ventricular blood pool. ECV values were compared between patients with and without PE, and correlations between ECV values and clinical or technical variables were subsequently appraised.

Results

Ninety-four patients were included, 63/94 of whom males (67%), with a median age of 70 (IQR 56−76 years); 28/94 (30%) patients presented with PE. Patients with PE had a higher myocardial ECV than those without (33.5%, IQR 29.4−37.5% versus 29.8%, IQR 25.1−34.0%; p = 0.010). There were no correlations between ECV and patients’ age (p = 0.870) or sex (p = 0.122), unenhanced scan voltage (p = 0.822), portal phase scan voltage (p = 0.631), overall radiation dose (p = 0.569), portal phase scan timing (p = 0.460), and contrast agent dose (p = 0.563).

Conclusions

CT-derived ECV could help identify COVID-19 patients at higher risk of cardiac dysfunction, especially when related to PE, to potentially plan a dedicated, patient-tailored clinical approach.

Long COVID: major findings, mechanisms and recommendations

Long COVID is an often debilitating illness that occurs in at least 10% of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. More than 200 symptoms have been identified with impacts on multiple organ systems. At least 65 million individuals worldwide are estimated to have long COVID, with cases increasing daily. Biomedical research has made substantial progress in identifying various pathophysiological changes and risk factors and in characterizing the illness; further, similarities with other viral-onset illnesses such as myalgic encephalomyelitis/chronic fatigue syndrome and postural orthostatic tachycardia syndrome have laid the groundwork for research in the field. In this Review, we explore the current literature and highlight key findings, the overlap with other conditions, the variable onset of symptoms, long COVID in children and the impact of vaccinations. Although these key findings are critical to understanding long COVID, current diagnostic and treatment options are insufficient, and clinical trials must be prioritized that address leading hypotheses. Additionally, to strengthen long COVID research, future studies must account for biases and SARS-CoV-2 testing issues, build on viral-onset research, be inclusive of marginalized populations and meaningfully engage patients throughout the research process.

Post-COVID-19 Syndrome Comprehensive Assessment: From Clinical Diagnosis to Imaging and Biochemical-Guided Diagnosis and Management

The COVID-19 outbreak was first reported in 2019, causing massive morbidity and mortality. The majority of the COVID-19 patients survived and developed Post-COVID-19 Syndrome (PC19S) of varying severity. Currently, the diagnosis of PC19S is achieved through history and symptomatology that cannot be explained by an alternative diagnosis. However, the heavy reliance on subjective reporting is prone to reporting errors. Besides, there is no unified diagnostic assessment tool to classify the clinical severity of patients. This leads to significant difficulties when managing patients in terms of public resource utilization, clinical progression monitorization and rehabilitation plan formulation. This narrative review aims to review current evidence of diagnosis based on triple assessment: clinical symptomatology, biochemical analysis and imaging evidence. Further assessment tools can be developed based on triple assessment to monitor patient's clinical progression, prognosis and intervals of monitoring. It also highlights the high-risk features of patients for closer and earlier monitoring. Rehabilitation programs and related clinical trials are evaluated; however, most of them focus on cardiorespiratory fitness and psychiatric presentations such as anxiety and depression. Further research is required to establish an objective and comprehensive assessment tool to facilitate clinical management and rehabilitation plans.

A Prospect to Ameliorate Affective Symptoms and to Enhance Cognition in Long COVID Using Auricular Transcutaneous Vagus Nerve Stimulation

Long COVID, the postviral disorder caused by COVID-19, is expected to become one of the leading causes of disability in Europe. The cognitive consequences of long COVID have been described as "brain fog" and characterized by anxiety and depression, and by cognitive deficits. Long COVID is assumed to be a complex condition arising from multiple causes, including persistent brainstem dysfunction and disrupted vagal signaling. We recommend the potential application of auricular transcutaneous vagus nerve stimulation (atVNS) as an ADD-ON instrument to compensate for the cognitive decline and to ameliorate affective symptoms caused by long COVID. This technique enhances vagal signaling by directly activating the nuclei in the brainstem, which are hypoactive in long COVID to enhance mood and to promote attention, memory, and cognitive control-factors affected by long COVID. Considering that atVNS is a non-pharmacological intervention, its ADD-ON to standard pharmaceutical agents will be useful for non-responders, making of this method a suitable tool. Given that atVNS can be employed as an ecological momentary intervention (EMI), we outline the translational advantages of atVNS in the context of accelerating the cognitive and affective recovery from long COVID.

Long COVID: An inevitable sequela of SARS-CoV-2 infection

At present, there are more than 560 million confirmed cases of the coronavirus disease 2019 (COVID-19) worldwide. Although more than 98% of patients with severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection can survive acute COVID, a significant portion of survivors can develop residual health problems, which is termed as long COVID. Although severe COVID-19 is generally associated with a high risk of long COVID, patients with asymptomatic or mild disease can also show long COVID. The definition of long COVID is inconsistent and its clinical manifestations are protean. In addition to general symptoms, such as fatigue, long COVID can affect many organ systems, including the respiratory, neurological, psychosocial, cardiovascular, gastrointestinal, and metabolic systems. Moreover, patients with long COVID may experience exercise intolerance and impaired daily function and quality of life. Long COVID may be caused by SARS-CoV-2 direct injury or its associated immune/inflammatory response. Assessment of patients with long COVID requires comprehensive evaluation, including history taking, physical examination, laboratory tests, radiography, and functional tests. However, there is no known effective treatment for long COVID. Based on the limited evidence, vaccines may help to prevent the development of long COVID. As long COVID is a new clinical entity that is constantly evolving, there are still many unknowns, and further investigation is warranted to enhance our understanding of this disease.

Microvascular Thrombosis as a Critical Factor in Severe COVID-19

Platelet-endothelial interactions have a critical role in microcirculatory function, which maintains tissue homeostasis. The subtle equilibrium between platelets and the vessel wall is disturbed by the coronavirus disease 2019 (COVID-19), which affects all three components of Virchow's triad (endothelial injury, stasis and a hypercoagulable state). Endotheliitis, vasculitis, glycocalyx degradation, alterations in blood flow and viscosity, neutrophil extracellular trap formation and microparticle shedding are only few pathomechanisms contributing to endothelial damage and microthrombosis resulting in capillary plugging and tissue ischemia. In the following opinion paper, we discuss major pathological processes leading to microvascular endothelial activation and thrombosis formation as a possible major adverse factor driving the deterioration of patient disease course in severe COVID-19.

Long COVID Symptomatology and Associated Factors in Primary Care Patients: The EPICOVID-AP21 Study

Persistent COVID-19 condition includes a wide variety of symptoms and health problems of indeterminate duration. The present study examined the sociodemographic and clinical characteristics of the population with Long COVID seen in Primary Care using a questionnaire based on the existing scientific literature. It was an observational and descriptive study of the characteristics of the Spanish population with Long COVID over 14 years of age. The responses were analysed by means of a descriptive analysis of the variables recorded, in addition to a bivariate analysis to determine the existence of a relationship between persistent COVID-19 and variables such as gender, age, vaccination status or concomitant pathology. The results obtained clearly describe the sociodemographic characteristics of the population, highlighting the predominance of female gender and the prevalence of tiredness and fatigue. Furthermore, relevant information was obtained on the differences in symptomatology according to gender, age, previous pathologies and alterations derived from infection and/or vaccination. These data are important for better detection, diagnosis and treatment of Long COVID and the improvement of the quality of life of this population.

One-year cardiovascular outcomes after coronavirus disease 2019: The cardiovascular COVID-19 registry

BACKGROUND

The long-term cardiovascular (CV) outcomes of COVID-19 have not been fully explored.

METHODS

This was an international, multicenter, retrospective cohort study conducted between February and December 2020. Consecutive patients ≥18 years who underwent a real-time reverse transcriptase-polymerase chain reaction (RT-PCR) for SARS-CoV2 were included. Patients were classified into two cohorts depending on the nasopharyngeal swab result and clinical status: confirmed COVID-19 (positive RT-PCR) and control (without suggestive symptoms and negative RT-PCR). Data were obtained from electronic records, and clinical follow-up was performed at 1-year. The primary outcome was CV death at 1-year. Secondary outcomes included arterial thrombotic events (ATE), venous thromboembolism (VTE), and serious cardiac arrhythmias. An independent clinical event committee adjudicated events. A Cox proportional hazards model adjusted for all baseline characteristics was used for comparing outcomes between groups. A prespecified landmark analysis was performed to assess events during the post-acute phase (31-365 days).

RESULTS

A total of 4,427 patients were included: 3,578 (80.8%) in the COVID-19 and 849 (19.2%) control cohorts. At one year, there were no significant differences in the primary endpoint of CV death between the COVID-19 and control cohorts (1.4% vs. 0.8%; HRadj 1.28 [0.56-2.91]; p = 0.555), but there was a higher risk of all-cause death (17.8% vs. 4.0%; HRadj 2.82 [1.99-4.0]; p = 0.001). COVID-19 cohort had higher rates of ATE (2.5% vs. 0.8%, HRadj 2.26 [1.02-4.99]; p = 0.044), VTE (3.7% vs. 0.4%, HRadj 9.33 [2.93-29.70]; p = 0.001), and serious cardiac arrhythmias (2.5% vs. 0.6%, HRadj 3.37 [1.35-8.46]; p = 0.010). During the post-acute phase, there were no significant differences in CV death (0.6% vs. 0.7%; HRadj 0.67 [0.25-1.80]; p = 0.425), but there was a higher risk of deep vein thrombosis (0.6% vs. 0.0%; p = 0.028). Re-hospitalization rate was lower in the COVID-19 cohort compared to the control cohort (13.9% vs. 20.6%; p = 0.001).

CONCLUSIONS

At 1-year, patients with COVID-19 experienced an increased risk of all-cause death and adverse CV events, including ATE, VTE, and serious cardiac arrhythmias, but not CV death.

STUDY REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT04359927.

Dysregulated haemostasis in thrombo-inflammatory disease

Inflammatory disease is often associated with an increased incidence of venous thromboembolism in affected patients, although in most instances, the mechanistic basis for this increased thrombogenicity remains poorly understood. Acute infection, as exemplified by sepsis, malaria and most recently, COVID-19, drives 'immunothrombosis', where the immune defence response to capture and neutralise invading pathogens causes concurrent activation of deleterious prothrombotic cellular and biological responses. Moreover, dysregulated innate and adaptive immune responses in patients with chronic inflammatory conditions, such as inflammatory bowel disease, allergies, and neurodegenerative disorders, are now recognised to occur in parallel with activation of coagulation. In this review, we describe the detailed cellular and biochemical mechanisms that cause inflammation-driven haemostatic dysregulation, including aberrant contact pathway activation, increased tissue factor activity and release, innate immune cell activation and programmed cell death, and T cell-mediated changes in thrombus resolution. In addition, we consider how lifestyle changes increasingly associated with modern life, such as circadian rhythm disruption, chronic stress and old age, are increasingly implicated in unbalancing haemostasis. Finally, we describe the emergence of potential therapies with broad-ranging immunothrombotic functions, and how drug development in this area is challenged by our nascent understanding of the key molecular and cellular parameters that control the shared nodes of proinflammatory and procoagulant pathways. Despite the increasing recognition and understanding of the prothrombotic nature of inflammatory disease, significant challenges remain in effectively managing affected patients, and new therapeutic approaches to curtail the key pathogenic steps in immune response-driven thrombosis are urgently required.

Mondor's disease of the breast: A cutaneous thromboembolic manifestation of Covid-19?

BACKGROUND

Mondor's disease is a rare disorder characterised by thrombosis of superficial veins within the subcutaneous tissue of the breast and other organs. While factors such as trauma, infection, physical exertion, breast cancer and breast surgery have been implicated, in the majority no cause is identified.

PATIENTS

Twenty patients presented with a clinical diagnosis of Mondor's disease to the Edinburgh Breast Services in 2020. We present the etiopathogenic data as well as clinical and imaging diagnostic findings.

RESULTS

During 2020, the annual incidence of Mondor's disease, in the UK's largest breast unit, increased five-fold compared to data from the previous year. This variation in the frequency of cases corresponded to trends in the frequency of Covid-19 infection during the pandemic. None of the patients had diagnosed COVID and few had any known etiopathogenic causes for their Mondor's.

CONCLUSION

Several recent studies have provided evidence for links between Covid-19 and thromboembolic events. Isolated reports have proposed a link between Covid-19 and Mondor's disease of the penis. Here we present data on a large series of Mondor's disease of the breast supporting a link between breast Mondor's and Covid-19.

The Challenge of Long COVID-19 Management: From Disease Molecular Hallmarks to the Proposal of Exercise as Therapy

Long coronavirus disease 19 (COVID-19) is the designation given to a novel syndrome that develops within a few months after infection by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and that is presenting with increasing incidence because of the numerous cases of infection. Long COVID-19 is characterized by a sequela of clinical symptoms that concern different organs and tissues, from nervous, respiratory, gastrointestinal, and renal systems to skeletal muscle and cardiovascular apparatus. The main common molecular cause for all long COVID-19 facets appears to be related to immune dysregulations, the persistence of inflammatory status, epigenetic modifications, and alterations of neurotrophin release. The prevention and management of long COVID-19 are still inappropriate because many aspects need further clarification. Exercise is known to exert a deep action on molecular dysfunctions elicited by long COVID-19 depending on training intensity, duration, and continuity. Evidence suggests that it could improve the quality of life of long COVID-19 patients. This review explores the main clinical features and the known molecular mechanisms underlying long COVID-19 in the perspective of considering exercise as a co-medication in long COVID-19 management.

The rationale for the treatment of long-Covid symptoms – A cardiologist's view

The ongoing coronavirus disease 2019 pandemic left us with thousands of patients suffering from neurological, cardiovascular, and psychiatric disorders named post-acute sequelae of COVID-19 or just long-Covid. In parallel, the vaccination campaigns against SARS-CoV-2 spike protein saved millions of lives worldwide but long-Covid symptoms also appeared rarely following vaccination with a strong overlap to the “canonical” long-Covid symptoms. A therapeutic strategy targeting both, post-VAC and post-SARS-CoV-2 long-Covid symptoms is warranted since exposure to the S-protein either by vaccination or SARS-CoV-2 infection may trigger identical immuno-inflammatory cascades resulting in long-Covid symptoms.

Venous Thromboembolic Disease in COVID-19, Pathophysiology, Therapy and Prophylaxis

For over two years, the world has been facing the epidemiological and health challenge of the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Growing problems are also complications after the development of COVID-19 in the form of post and long- COVID syndromes, posing a challenge for the medical community, both for clinicians and the scientific world. SARS-CoV-2 infection is associated with an increased risk of cardiovascular complications, especially thromboembolic complications, which are associated with both thrombosis of small and very small vessels due to immunothrombosis, and the development of venous thromboembolism. Low molecular wight heparin (LMHW) are the basic agents used in the prevention and treatment of thromboembolic complications in COVID-19. There is still a great deal of controversy regarding both the prevention and treatment of thromboembolic complications, including the prophylaxis dose or the optimal duration of anticoagulant treatment in patients with an episode of venous thromboembolism.

Combining L-Arginine with vitamin C improves long-COVID symptoms: The LINCOLN Survey

INTRODUCTION

Recent evidence suggests that oxidative stress and endothelial dysfunction play critical roles in the pathophysiology of COVID-19 and Long-COVID. We hypothesized that a supplementation combining L-Arginine (to improve endothelial function) and Vitamin C (to reduce oxidation) could have favorable effects on Long-COVID symptoms.

METHODS

We designed a survey (LINCOLN: L-Arginine and Vitamin C improves Long-COVID), assessing several symptoms that have been associated with Long-COVID to be administered nationwide to COVID-19 survivors; the survey also included effort perception, measured using the Borg scale. Patients receiving the survey were divided in two groups, with a 2:1 ratio: the first group included patients that received L-Arginine + Vitamin C, whereas the second group received a multivitamin combination (alternative treatment).

RESULTS

1390 patients successfully completed the survey. Following a 30-day treatment in both groups, the survey revealed that patients in the L-Arginine + Vitamin C treatment arm had significantly lower scores compared to patients who had received the multivitamin combination. There were no other significant differences between the two groups. When examining effort perception, we observed a significantly lower value (p < 0.0001) in patients receiving L-Arginine + Vitamin C compared to the alternative-treatment arm.

CONCLUSIONS

Our survey indicates that the supplementation with L-Arginine + Vitamin C has beneficial effects in Long-COVID, in terms of attenuating its typical symptoms and improving effort perception.

Risk of Pulmonary Fibrosis and Persistent Symptoms Post-COVID-19 in a Cohort of Outpatient Health Workers

Background: Infection by SARS-CoV-2 has been associated with multiple symptoms; however, still, little is known about persistent symptoms and their probable association with the risk of developing pulmonary fibrosis in patients post-COVID-19. Methods: A longitudinal prospective study on health workers infected by SARS-CoV-2 was conducted. In this work, signs and symptoms were recorded of 149 health workers with a positive PCR test for SARS-CoV-2 at the beginning of the diagnosis, during the active infection, and during post-COVID-19 follow-up. The McNemar chi-square test was used to compare the proportions and percentages of symptoms between the baseline and each follow-up period. Results: The signs and symptoms after follow-up were cardiorespiratory, neurological, and inflammatory. Gastrointestinal symptoms were unusual at the disease onset, but unexpectedly, their frequency was higher in the post-infection stage. The multivariate analysis showed that pneumonia (HR 2.4, IC95%: 1.5−3.8, p < 0.001) and positive PCR tests still after four weeks (HR 5.3, IC95%: 2.3-12.3, p < 0.001) were factors associated with the diagnosis of post-COVID-19 pulmonary fibrosis in this study group. Conclusions: Our results showed that pneumonia and virus infection persistence were risk factors for developing pulmonary fibrosis post-COVID-19, after months of initial infection.

Pulmonary Embolism in Post-CoviD-19 Patients, a Literature Review: Red Flag for Increased Awareness?

Although COVID-19 was primarily considered a respiratory illness, rapidly accumulating data suggest that COVID-19 is associated with a high incidence of venous thromboembolic complications. The primary objective of this review article was to reveal whether we need to increase awareness of pulmonary embolism in the period following the COVID-19 infection given that the epidemiologic facts are still poor. A literature search and a critical review of the collected studies were conducted. An electronic search of PubMed, Science Direct Scopus, Google Scholar, and Excerpta Medica Database (EMBASE) from June 2020 until June 2022. The long-term health consequences of COVID-19 remain largely unclear. This review highlights the importance of awareness of the potentially increased incidence of venous thromboembolism in post-COVID-19 patients, even those with mild or asymptomatic disease. Further research is required to establish appropriate clinical management guidelines for the prevention of thromboembolic complications in the post-COVID-19 period.