COVID-19 Associated Coagulopathy and Thrombotic Complications

Roles of spectral dual-layer CT, D-dimer concentration, and COVID-19 pneumonia in diagnosis of pulmonary embolism

Purpose

To demonstrate advantages of spectral dual-layer computed tomography (CT) in diagnosing pulmonary embolism (PE). To compare D-dimer values in patients with PE and concomitant COVID-19 pneumonia to those in patients without PE and COVID-19 pneumonia. To compare D-dimer values in cases of minor versus extensive PE.

Methods

A monocentric retrospective study of 1500 CT pulmonary angiographies (CTPAs). Three groups of 500 consecutive examinations: 1) using conventional multidetector CT (CTC), 2) using spectral dual-layer CT (CTS), and 3) of COVID-19 pneumonia patients using spectral dual-layer CT (COV). Only patients with known D-dimer levels were enrolled in the study.

Results

Prevalence of inconclusive PE findings differed significantly between CTS and CTC (0.8 % vs. 5.4 %, p < 0.001). In all groups, D-dimer levels were significantly higher in PE positive patients than in patients without PE (CTC, 8.04 vs. 3.05 mg/L; CTS, 6.92 vs. 2.57 mg/L; COV, 10.26 vs. 2.72 mg/L, p < 0.001). There were also statistically significant differences in D-dimer values between minor and extensive PE in the groups negative for COVID-19 (CTC, 5.16 vs. 8.98 mg/L; CTS 3.52 vs. 9.27 mg/L, p < 0.001). The lowest recorded D-dimer value for proven PE in patients with COVID-19 pneumonia was 1.19 mg/L.

Conclusion

CTPAs using spectral dual-layer CT reduce the number of inconclusive PE findings. Plasma D-dimer concentration increases with extent of PE. Cut-off value of D-dimer with 100 % sensitivity for patients with COVID-19 pneumonia could be doubled to 1.0 mg/L. This threshold would have saved 110 (22 %) examinations in our cohort.

Spectrum of Thrombotic Complications in Fatal Cases of COVID-19: Focus on Pulmonary Artery Thrombosis In Situ

COVID-19-related thrombosis affects the venous and arterial systems. Data from 156 autopsies of COVID-19 patients were retrospectively analyzed to investigate the pattern of thrombotic complications and factors associated with pulmonary artery thrombosis and thromboembolism. Thrombotic complications were observed in a significant proportion (n = 68, 44%), with pulmonary artery thrombosis the most frequently identified thrombotic event (42, 27%). Multivariate analysis revealed that the length of hospital stay (OR 1.1, p = 0.004), neutrophil infiltration in the alveolar spaces (OR 3.6, p = 0.002), and the absence of hyaline membranes (OR 0.1, p = 0.01) were associated with thrombotic complications. Neutrophil infiltration in the alveolar spaces (OR 8, p < 0.001) and the absence of hyaline membranes (OR 0.1, p = 0.003) were also independent predictors of pulmonary artery thrombosis. The association of pulmonary artery thrombosis with an absence of hyaline membranes suggests it occurs later in the course of COVID-19 infection. As neutrophil infiltration in the alveolar spaces may indicate bacterial infection, our studies suggest the consideration of bacterial infections in these critically ill patients.

Coagulation Profile of COVID-19 Patients

Coronavirus disease is a viral infection that can affect multiple systems and be expressed with many-or no-symptoms. The viral infection begins when the virus binds to the host's receptor and from that point on, it is transmitted to the rest of the body, where it causes inflammatory reactions. Among other tissues and systems, SARS-CoV-2 impacts the coagulation system, where it triggers the immunothrombotic response. Its effects are rather intense and can lead to many complications. COVID-19-associated coagulopathy is frequently observed in hospitalized patients, especially ICU patients, and can be proven detrimental. It is usually accompanied by other complications, such as sepsis-induced coagulopathy, disseminated intravascular coagulation and venous thromboembolism. Since all these conditions lead to poor prognosis for severely ill patients, thromboprophylaxis and coagulopathy prognosis are just as important as the therapeutic handling of these patients. Since the beginning of the pandemic, many biomarkers have been considered useful when trying to assess the thrombotic risk of hospitalized patients or evaluate the severity of their situation. At the same time, many drugs have already been tested-while others are still being trialed-in order to find the optimal therapy for each urgent situation.

Early-stage COVID-19 pandemic observations on pulmonary embolism using nationwide multi-institutional data harvesting

We introduce a multi-institutional data harvesting (MIDH) method for longitudinal observation of medical imaging utilization and reporting. By tracking both large-scale utilization and clinical imaging results data, the MIDH approach is targeted at measuring surrogates for important disease-related observational quantities over time. To quantitatively investigate its clinical applicability, we performed a retrospective multi-institutional study encompassing 13 healthcare systems throughout the United States before and after the 2020 COVID-19 pandemic. Using repurposed software infrastructure of a commercial AI-based image analysis service, we harvested data on medical imaging service requests and radiology reports for 40,037 computed tomography pulmonary angiograms (CTPA) to evaluate for pulmonary embolism (PE). Specifically, we compared two 70-day observational periods, namely (i) a pre-pandemic control period from 11/25/2019 through 2/2/2020, and (ii) a period during the early COVID-19 pandemic from 3/8/2020 through 5/16/2020. Natural language processing (NLP) on final radiology reports served as the ground truth for identifying positive PE cases, where we found an NLP accuracy of 98% for classifying radiology reports as positive or negative for PE based on a manual review of 2,400 radiology reports. Fewer CTPA exams were performed during the early COVID-19 pandemic than during the pre-pandemic period (9806 vs. 12,106). However, the PE positivity rate was significantly higher (11.6 vs. 9.9%, p < 10^-4) with an excess of 92 PE cases during the early COVID-19 outbreak, i.e., ~1.3 daily PE cases more than statistically expected. Our results suggest that MIDH can contribute value as an exploratory tool, aiming at a better understanding of pandemic-related effects on healthcare.

Comorbidities and clinical complications associated with SARS-CoV-2 infection: an overview

The novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes major challenges to the healthcare system. SARS-CoV-2 infection leads to millions of deaths worldwide and the mortality rate is found to be greatly associated with pre-existing clinical conditions. The existing dataset strongly suggests that cardiometabolic diseases including hypertension, coronary artery disease, diabetes and obesity serve as strong comorbidities in coronavirus disease (COVID-19). Studies have also shown the poor outcome of COVID-19 in patients associated with angiotensin-converting enzyme-2 polymorphism, cancer chemotherapy, chronic kidney disease, thyroid disorder, or coagulation dysfunction. A severe complication of COVID-19 is mostly seen in people with compromised medical history. SARS-CoV-2 appears to attack the respiratory system causing pneumonia, acute respiratory distress syndrome, which lead to induction of severe systemic inflammation, multi-organ dysfunction, and death mostly in the patients who are associated with pre-existing comorbidity factors. In this article, we highlighted the key comorbidities and a variety of clinical complications associated with COVID-19 for a better understanding of the etiopathogenesis of COVID-19.

Pathological effects of SARS-CoV-2 on hematological and immunological cells: Alterations in count, morphology, and function

The novel Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), the causative agent of COVID-19 outbreak, spread rapidly and infected more than 140 million people with more than three million victims worldwide. The SARS-CoV-2 causes destructive changes in the immunological and hematological system of the host. These alterations appear to play a critical role in disease pathology and the emerging of clinical manifestations. In this review, we aimed to discuss the effect of COVID-19 on the count, function and morphology of immune and blood cells and the role of these changes in the pathophysiology of the disease. Knowledge of these changes may help with better management and treatment of COVID-19 patients.

Two Different Clinical Presentations of Acute Limb Ischemia Caused by Acute Thrombotic Events in COVID-19

Coronavirus disease 2019 (COVID-19) is a global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Coagulopathy is frequently found in severe cases of COVID-19 and is usually manifested as a prothrombotic state. Hyperinflammation, endotheliitis, and immobilization during illness are hypothesized to play a role. Acute limb ischemia (ALI) is one of the presentations of arterial thrombosis in COVID-19. We present two cases of middle-aged men with COVID-19 infection, who developed ALI. The first patient developed ALI after 16 days from the initial COVID-19 diagnosis, and the second patient was admitted to the emergency ward due to sudden discoloration of his right lower limb, and COVID-19 was diagnosed during the evaluation.

Case of right ventricular and aortic thrombi in a patient with severe COVID-19

Emerging evidence suggests that novel COVID-19 is associated with increased prothrombotic state and risk of thromboembolic complications, particularly in severe disease. COVID-19 is known to predispose to both venous and arterial thrombotic disease. We describe a case of a 61-year-old woman with history of type II diabetes, hypertension and hyperlipidaemia who presented with dry cough and acute abdominal pain. She was found to have a significantly elevated D-dimer, prompting imaging that showed thrombi in her right ventricle and aorta. She had rapid clinical deterioration and eventually required tissue plasminogen activator with subsequent durable clinical improvement. This case highlights a rare co-occurrence of venous and arterial thrombi in a patient with severe COVID-19. Further studies are needed to clarify the molecular mechanism of COVID-19 coagulopathy, the utility of D-dimer to predict and stratify risk of thrombosis in COVID-19, and the use of fibrinolytic therapy in patients with COVID-19.

The Impact of COVID-19 on Vascular Surgery Practice: A Systematic Review

BACKGROUND

COVID-19 is characterized by a pulmonary interstitial compromise which can require intensive care unit (ICU) and mechanical ventilation. Covid patients develop a wide range of pathologies. This study aims to identify the impact of COVID-19 in diseases commonly treated by vascular surgeons.

METHODS

Four conditions were selected: venous thromboembolism (VTE), pulmonary embolism (PE), peripheral arterial disease (PAD), and microangiopathy. A systematic review of the literature using PRISMA guidelines was.

RESULTS

Out of 1195 papers reviewed for conditions in COVID-19 patients relevant to routine vascular surgery practice, 43 papers were included and analyzed. Venous thrombosis was found to be the most common COVID-19 associated pathology with a cumulative incidence of 25% at 7 days and 48% at 14 days. Additionally, D-dimer levels proved to be a good predictor, even in the early stages of the disease with a sensitivity of 85%, specificity of 88.5% and a negative predictive value of 94.7%. Patients in the ICU demonstrated a significantly higher risk of developing VTE, even when receiving pharmacologic thromboprophylaxis. Although evidence of arterial thrombosis was less common (1% to 16.3%), its consequences were typically more serious, including limb loss and death even in young individuals (OR = 25, 95% CI). Finally, microangiopathy has a wide spectrum of clinical presentations from retinal microangiopathy to other more severe manifestations such as myocardial injury, pulmonary compromise and potential multiple organ dysfunction syndrome.

CONCLUSIONS

Although the pathophysiological pathway by which COVID-19 produces thrombosis is not completely clear, the incidence of both arterial and venous thrombosis is increased. D-dimer screening should be done in all COVID-19 patients, as a predictor of thrombotic complications.

Systemic arterio-venous thrombosis in COVID-19: A pictorial review

Coronavirus disease 2019 (COVID-19) is caused by the novel coronavirus severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Systemic complications include cardiovascular, neurological, hepatic, renal and altered coagulation. Derangements in haemostasis with SARS-CoV-2 infection have been termed COVID-19 associated coagulopathy (CAC). CAC is postulated to be one of the significant causes for sudden deaths in this pandemic, with infection of endothelial cells and subsequent endotheliitis through angiotensin-converting enzyme-2 receptors playing a key role in the pathogenesis. In this pictorial review, we describe the imaging findings in a multitude of extrapulmonary arterial (aorta, cerebral, mesenteric, renal and peripheral arterial system) and venous thrombotic phenomena detected on contrast-enhanced computed tomography and magnetic resonance imaging of COVID-19 patients which could not be attributed to any other causes. Knowledge of incidence of these complications, lowering the threshold for diagnostic imaging in symptomatic patients and timely radiological detection can play a vital role in subsequent management of these critically ill patients.

Flavonols as potential antiviral drugs targeting SARS-CoV-2 proteases (3CLpro and PLpro), spike protein, RNA-dependent RNA polymerase (RdRp) and angiotensin-converting enzyme II receptor (ACE2)

The novel coronavirus outbreak (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents the actual greatest global public health crisis. The lack of efficacious drugs and vaccines against this viral infection created a challenge for scientific researchers in order to find effective solutions. One of the promising therapeutic approaches is the search for bioactive molecules with few side effects that display antiviral properties in natural sources like medicinal plants and vegetables. Several computational and experimental studies indicated that flavonoids especially flavonols and their derivatives constitute effective viral enzyme inhibitors and possess interesting antiviral activities. In this context, the present study reviews the efficacy of many dietary flavonols as potential antiviral drugs targeting the SARS-CoV-2 enzymes and proteins including Chymotrypsin-Like Protease (3CLpro), Papain Like protease (PLpro), Spike protein (S protein) and RNA-dependent RNA polymerase (RdRp), and also their ability to interact with the angiotensin-converting enzyme II (ACE2) receptor. The relationship between flavonol structures and their SARS-CoV-2 antiviral effects were discussed. On the other hand, the immunomodulatory, the anti-inflammatory and the antiviral effects of secondary metabolites from this class of flavonoids were reported. Also, their bioavailability limitations and toxicity were predicted.

Extensive Arterial Thrombus Following Discharge after a Covid-19 Infection

The novel coronavirus pandemic is associated with coagulopathy and an increased risk of thromboembolic events. A case of an extensive arterial thrombus in the left leg of a patient that occurred after discharge from Covid-19 pneumonia is described. Some patients may be under continued risk of thromboembolism after discharge and the value of extended thromboprophylaxis should be investigated.

Current state of vaccine development and targeted therapies for COVID-19: impact of basic science discoveries

Coronavirus disease-19 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 is closely related to two other coronaviruses that caused disease epidemic breakouts in humans in the last 2 decades, namely, severe acute respiratory distress syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). The similarities have enabled the scientists to apply the basic scientific discoveries garnered from studying the structure and modus operandi of SARS-CoV and MERS-CoV to develop therapies that specifically target SARS-CoV-2 and to develop vaccines to prevent COVID-19. Targeted therapies including the use of antibodies to prevent virus entry, nucleotide analogues to prevent viral replication, and inhibitors of proteases to prevent virion formation, among others, are being tested for their clinical efficacy. Likewise, complete sequencing of the SARS-CoV-2 and identification of its structural and nonstructural proteins have enabled development of RNA-, DNA-, and peptide-based vaccines as well attenuated viral vaccines to instigate the host-immune responses. The clinical impacts of the basic science discoveries are amply evident on the rapid pace of progress in developing specific antiviral therapies and vaccines against SARS-CoV-2. The progress emphasizes the merit of discovering the fundamental scientific elements, regardless of whether or not they have apparent or immediate clinical applications.

A case report of multisite arterial thrombosis in a patient with coronavirus disease 2019 (COVID-19)

Background

A systemic coagulation dysfunction has been associated with COVID-19. In this case report, we describe a COVID-19-positive patient with multisite arterial thrombosis, presenting with acute limb ischaemia and concomitant ST-elevation myocardial infarction and oligo-symptomatic lung disease.

Case summary

An 83-year-old lady with history of hypertension and chronic kidney disease presented to the Emergency Department with acute-onset left leg pain, pulselessness, and partial loss of motor function. Acute limb ischaemia was diagnosed. At the same time, a routine ECG showed ST-segment elevation, diagnostic for inferior myocardial infarction. On admission, a nasopharyngeal swab was performed to assess the presence of SARS-CoV-2, as per hospital protocol during the current COVID-19 pandemic. A total-body CT angiography was performed to investigate the cause of acute limb ischaemia and to rule out aortic dissection; the examination showed a total occlusion of the left common iliac artery and a non-obstructive thrombosis of a subsegmental pulmonary artery branch in the right basal lobe. Lung CT scan confirmed a typical pattern of interstitial COVID-19 pneumonia. Coronary angiography showed a thrombotic occlusion of the proximal segment of the right coronary artery. Percutaneous coronary intervention was performed, with manual thrombectomy, followed by deployment of two stents. The patient was subsequently transferred to the operating room, where a Fogarty thrombectomy was performed. The patient was then admitted to the COVID area of our hospital. Seven hours later, the swab returned positive for COVID-19.

Discussion

COVID-19 can have an atypical presentation with thrombosis at multiple sites.

More Severe Hypercoagulable State in Acute COVID-19 Pneumonia as Compared With Other Pneumonia

Objective

To conduct a comprehensive evaluation of coagulation profiles—via traditional and whole blood thromboelastometry tests—in coronavirus disease 2019 (COVID-19)–positive vs COVID-19–negative patients admitted to medical wards for acute pneumonia.

Patients and Methods

We enrolled all consecutive patients admitted to internal medicine wards of Padova University Hospital between 7 March and 30 April, 2020, for COVID-19–related pneumonia (cases) vs non–COVID-19 pneumonia (controls). A group of healthy individuals acted as baseline for thromboelastometry parameters.

Results

Fifty-six cases (mean age, 64±15 years; male/female, 37/19) and 56 controls (mean age, 76±11 years; male/female, 35/21) were enrolled. Cases and controls exhibited markedly hypercoagulable thromboelastometry profiles vs healthy individuals, mainly characterized by a significantly shorter propagation phase of coagulation (clot formation time) and significantly increased maximum clot firmness (P<.001 for all comparisons). Patients with COVID-19 pneumonia had significantly shorter clot formation time and higher maximum clot firmness (P<.01 and P<.05, respectively, for all comparisons) than did controls.

Conclusion

Patients admitted to internal medicine wards for COVID-19 pneumonia presented a markedly prothrombotic state, which seems peculiar to COVID-19 rather than pneumonia itself.