Acute pulmonary embolism in times of SARS-CoV-2: Diagnostic and therapeutic management / Tromboembolismo pulmonar agudo en tiempos de SARS-CoV-2: diagnóstico y tratamiento

There is a clear association between novel coronavirus 2 infection and the diagnosis of venous thromboembolic disease, as a cosequence of the development of a systemic inflammatory response syndrome due to the activation of the coagulation cascade. It occurs in 90% of patients with severe forms of the infection, evidencing the presence of pulmonary endovascular micro and macro thrombosis. This suggests a possible clinical benefit of thromboprophylaxis according to the patient's clinical risk. The suspicion of venous thromboembolic disease in the context of this pandemic represents a diagnostic challenge due to the co-existence of similarities between both conditions in several different aspects. It should be noted that the diagnosis of acute pulmonary embolism does not exclude the possibility of simultaneous viral infection. The evaluation of patients with suspected acute pulmonary embolism in the context of the pandemic should be optimized in order to implement a rapid diagnosis and treatment to reduce the associated morbidity and mortality. This will help reducing infectious risk for health-care professionals and other patients.

Existe una clara relación entre la infección por el nuevo coronavirus 2 y el diagnóstico de enfermedad tromboembólica venosa, como consecuencia del desarrollo de un síndrome de respuesta inflamatoria sistémica debido a la activación de la cascada de la coagulación. Se presenta en el 90% de los pacientes con formas graves de la infección, lo que revela la presencia de microtrombosis y macrotrombosis intravascular pulmonar. Esto sugiere un posible beneficio clínico de la aplicación de una tromboprofilaxis adecuada al riesgo clínico de cada paciente. Asimismo, la sospecha de enfermedad tromboembólica venosa en el contexto de esta pandemia representa un reto diagnóstico debido a la existencia de similitudes entre ambas alteraciones en varios aspectos. Debe tenerse en cuenta que el diagnóstico de tromboembolismo pulmonar agudo no excluye la posibilidad de infección viral. La valoración de pacientes con sospecha de tromboembolismo pulmonar agudo en el contexto de la pandemia debe ser eficaz para establecer un diagnóstico y tratamiento con rapidez, a fin de reducir la morbilidad y mortalidad adjuntas, sin que ello eleve el riesgo de infección para los profesionales de la salud y otros pacientes.

Pulmonary artery angiomatoid fibrous histiocytoma mimicking pulmonary embolism.

A young man presented to the emergency department with pleuritic chest pain and shortness of breath. Of note, he recently went on a long-distance flight of about 9 hours. Given his recent long-distance travel and clinical symptoms, a pulmonary embolism was suspected. However, pathological examination of the excised pulmonary artery intraluminal mass demonstrated an angiomatoid fibrous histiocytoma. This case describes the clinicopathological and immunohistochemical features and molecular profile of a rare type of pulmonary artery tumour, a pulmonary artery angiomatoid fibrous histiocytoma.

Pulmonary hypertension, pulmonary embolism and COVID-19: A district general hospital experience from the UK.

BACKGROUND: Preliminary data suggest that the prevalence of pulmonary hypertension (PH) in patients with COVID-19 is around 13%, but its prognostic role remains unclear. Approximately 3% of patients develop chronic thrombo-embolic pulmonary hypertension (CTEPH) following diagnosis of acute pulmonary embolism (PE). It is recommended that patients are screened for CTEPH if they remain symptomatic 3 months following diagnosis of PE. The primary aim of the study was to assess the chances of persistent PH following PE secondary to COVID-19. METHODS: We conducted a retrospective cohort study at a District General Hospital (DGH) in the United Kingdom. All patients diagnosed with COVID-19 and PE between April 2020 and October 2021 were examined. Patients were divided into two groups:·COVID-19 and PE with comorbidities (excluding pre-existing PH) and·COVID-19 and PE without comorbidities. We compared the ECHO features suggestive of PH between the two groups at the time of diagnosis of PE and at 3 months following treatment. RESULTS: 80 patients were included in the study (49 with comorbidities and 31 with no comorbidities). Average age of comorbidities and no comorbidities groups were 73 years and 70 years, respectively. Average PaO2/FiO2 ratio for comorbidities and no comorbidities groups were 170 and 195, respectively. Fourteen patients (13 with comorbidities and 1 with no comorbidities) died in total. Results showed that risk of persistent PH and subsequent mortality following PE in COVID-19 is 4.17 times and 1.32 times more in comorbidity group as compared to no comorbidity group, respectively (p < 0.001). CONCLUSION: Patients with comorbidities are at high risk of persistent PH and mortality due to PE secondary to COVID-19.

Pulmonary embolism in COVID-19, risk factors and association with inflammatory biomarkers.

The coronavirus disease 2019 (COVID-19) pandemic affected millions of people worldwide resulting in a substantial number of hospitalizations. Venous thromboembolism including pulmonary embolism is a known complication of COVID-19 pneumonia although its incidence in such patients is unclear. In this multicenter retrospective cohort study, we looked at the incidence of pulmonary embolism in COVID-19 patients and its associations with various risk factors including demographics, comorbidities, inflammatory markers and coagulation profiles. We analyzed data from 193 patients of mixed ethnicity with a mean age of 51, mostly South Asians (62%) and Arabs (29%). Diabetes and hypertension were the most prevalent comorbidities accounting for 46% (N = 88) and 36% (N = 71) respectively. Critical COVID-19 illness was diagnosed in 67% of patients. The frequency of COVID-19 related pulmonary embolism was 21.8% (N = 42). We found no association of pulmonary embolism with demographic, comorbid or inflammatory variables. Only a raised D-Dimer was found to be associated with pulmonary embolism. Having a pulmonary embolism had no impact on the length of stay, critical illness, or mortality. Receiving steroids or being on standard thromboprophylaxis or weight/D-Dimer adjusted thromboprophylaxis also had no impact on the frequency of pulmonary embolism. Nine incidents of major bleeding were recorded independent of therapeutic anticoagulation. Patients admitted to the hospital for COVID-19 pneumonia had a relatively high incidence of pulmonary embolism. D-dimer was the only associated laboratory parameter associated with pulmonary embolism. However, further research is needed to evaluate its predictive and prognostic utility, particularly in an older population.

Isolated pulmonary embolism - a specific clinical entity?

Pulmonary embolism in classical meaning is a complication of deep vein thrombosis (usually in the leg veins), developing after a part of the thrombus dislodged and got wedged in pulmonary arteries. However, in half of the patients with pulmonary embolism, deep vein thrombosis is not found. One potential explanation is a different, less common location of the thrombus or previous complete embolization of the whole thrombotic mass. Another possibility is pulmonary artery thrombosis in situ, which is a specific clinical entity associated with some typical risk factors. It develops in the place of vascular injury, as a consequence of hypoxia, inflammatory changes, endothelial dysfunction and injury. Pulmonary artery thrombosis in situ can be a complication after lung resection, radiation therapy, chest trauma, in the patients with Behçet´s disease, sickle cell anemia, chronic obstructive pulmonary disease, tuberculosis or covid pneumonia. Pulmonary artery thrombosis in situ may differ from classical pulmonary embolism in prognosis as well as in therapeutic approach.

Predictors and outcomes of acute pulmonary embolism in COVID-19; insights from US National COVID cohort collaborative.

OBJECTIVES: To investigate whether COVID-19 patients with pulmonary embolism had higher mortality and assess the utility of D-dimer in predicting acute pulmonary embolism. PATIENTS AND METHODS: Using the National Collaborative COVID-19 retrospective cohort, a cohort of hospitalized COVID-19 patients was studied to compare 90-day mortality and intubation outcomes in patients with and without pulmonary embolism in a multivariable cox regression analysis. The secondary measured outcomes in 1:4 propensity score-matched analysis included length of stay, chest pain incidence, heart rate, history of pulmonary embolism or DVT, and admission laboratory parameters. RESULTS: Among 31,500 hospitalized COVID-19 patients, 1117 (3.5%) patients were diagnosed with acute pulmonary embolism. Patients with acute pulmonary embolism were noted to have higher mortality (23.6% vs.12.8%; adjusted Hazard Ratio (aHR) = 1.36, 95% CI [1.20-1.55]), and intubation rates (17.6% vs. 9.3%, aHR = 1.38[1.18-1.61]). Pulmonary embolism patients had higher admission D-dimer FEU (Odds Ratio(OR) = 1.13; 95%CI [1.1-1.15]). As the D-dimer value increased, the specificity, positive predictive value, and accuracy of the test increased; however, sensitivity decreased (AUC 0.70). At cut-off D-dimer FEU 1.8 mcg/ml, the test had clinical utility (accuracy 70%) in predicting pulmonary embolism. Patients with acute pulmonary embolism had a higher incidence of chest pain and history of pulmonary embolism or deep vein thrombosis. CONCLUSIONS: Acute pulmonary embolism is associated with worse mortality and morbidity outcomes in COVID-19. We present D-dimer as a predictive risk tool in the form of a clinical calculator for the diagnosis of acute pulmonary embolism in COVID-19.

Giant haematoma of the posterior compartment of thigh in a patient with coronavirus disease 19 pneumonia and pulmonary embolism - Case Report.

Introduction. During the Coronavirus-19 (Covid-19) pandemic, a significant increase in the frequency of complications in the form of venous thrombosis was observed. However, there is also the other side of the coin - an increase in the tendency to bleeding in the course of COVID19. Case Report. We present the case of a patient hospitalised in the COVID-19 Isolation Ward due to severe pneumonia in the course of SARS-CoV2 infection. She developed respiratory failure requiring a non-invasive mechanical ventilation. In addition, pulmonary embolism was diagnosed, the treatment with low molecule heparin was initiated. Soon, the patient developed a huge haematoma of the posterior compartment of the thigh causing deformation and dysfunction of the limb and resulting with acute haemorrhagic anaemia. Conclusion. Our article is a contribution to the discussion on the need to pay attention to the possibility of haemorrhagic complications in the course of anticoagulant treatment due to venous thrombosis in COVID-19 patients.

Diagnosis of COVID-19 in Patients with Acute Pulmonary Embolism.

Acute pulmonary embolism (PE) and coronavirus disease -2019 (COVID-19) are life-threatening diseases associated with significant morbidity and mortality. Yet little is known about their co-existence.This study explored clinical and laboratory differences between PE patients who tested positive with real-time reverse-transcription polymerase chain reaction (PCR+) and those who tested negative (PCR-) for SARS-CoV-2. Also, to determine whether ferritin D-dimer ratio (FDR) and platelet D-dimer ratio (PDR) can be used to predict COVID-19 in patients with PE. Files of 556 patients who underwent a computed tomography pulmonary angography (CTPA) examination were retrospectively investigated. Out of them, 197 were tested positive and 188 negative for SARS-CoV-2. One hundred thirteen patients (57.36%) in the PCR+ group and 113 (60.11%) in the PCR- group had a diagnosis of PE. Complaints, respiratory rate, and oxygen saturation level in the blood (SpO2) were recorded at the first admission. Monocyte and eosinophil levels remained low, whereas FDR and PDR were higher in the PCR+ group. No difference was detected in ferritin, D-dimer levels, comorbidities, SpO2, and death rates between the two groups. Cough, fever, joint pain, and higher respiratory rate were more common in the PCR+ group. A decrease in white blood cell, monocyte, and eosinophil levels, whereas an increase in FDR and PDR levels may predict COVID-19 in patients with PE. PE patients complaining of cough, fever, and fatigue should undergo PCR testing as common symptoms. COVID-19 does not seem to increase the risk of mortality in patients with PE.

Impact of COVID-19 Infection on the Clinical Outcomes of Pulmonary Embolism Hospitalizations : A Nationwide Analysis.

There is an increased risk of venous thromboembolism among patients with COVID-19 infection, with the risk being higher among those needing the intensive level of care. Existing data is, however, limited regarding the outcomes of patients admitted with concurrent COVID-19 infection and pulmonary embolism (PE). All acute PE admissions were identified from the National Inpatient Sample database during 2020 using ICD-10 codes. Patients were subsequently classified into those with and without COVID-19 infection. The primary outcome of interest was in-hospital mortality. Using multivariate logistic regression, the predictors of mortality were assessed for patients with concurrent acute PE and COVID-19. The database query generated 278,840 adult patients with a primary diagnosis of PE. Of these, 4580 patients had concurrent PE and COVID-19 infection. The concurrent PE and COVID-19 infection group had a higher proportion of Black-American and Hispanic patients, and those living in the zip codes associated with the lowest annualized income compared to the PE alone group. Furthermore, patients in the concurrent PE and COVID-19 infection group had an increased risk of in-hospital mortality (adjusted odds ratio [aOR]:1.62; 95% CI: 1.17-2.24; P = 0.004), septic shock (aOR: 1.66; 95% CI 1.10-2.52; P = 0.016), respiratory failure (aOR: 1.78; 95% CI 1.53-2.06; P = 0.001), and a longer hospital stay [5.5 days vs 4.59 days; P = 0.001). Concurrent COVID-19 and PE admissions is associated with an increased in-hospital mortality, risk of septic shock and respiratory failure, and a longer length of hospital stay.

Impact of COVID-19 on Patients Hospitalized With Deep Vein Thrombosis and/or Pulmonary Embolism: A Nationwide Analysis.

The Coronavirus disease 2019 (COVID-19) infection predisposes patients to develop deep vein thrombosis (DVT) and pulmonary embolism (PE). In this study, we compared the in-hospital outcomes of patients with DVT and/or PE with concurrent COVID-19 infection vs those with concurrent flu infection. The National Inpatient Sample from 2019 to 2020 was analyzed to identify all adult admissions diagnosed with DVT and PE. These patients were then stratified based on whether they had concomitant COVID-19 or flu. We identified 62,895 hospitalizations with the diagnosis of DVT and/or PE with concomitant COVID-19, and 8155 hospitalizations with DVT and/or PE with concomitant flu infection. After 1:1 propensity score match, the incidence of cardiac arrest and inpatient mortality were higher in the COVID-19 group. The incidence of cardiogenic shock was higher in the flu group. Increased age, Hispanic race, diabetes, chronic kidney disease, arrhythmia, liver disease, coagulopathy, and rheumatologic diseases were the independent predictors of mortality in patients with DVT and/or PE with concomitant COVID-19.

["Guiding lights" for the diagnosis of chronic thromboembolic pulmonary hypertension in the flow of patients with pulmonary embolism].

On December 13, 2021, an expert council was held to determine the position of experts of different specialties regarding the reasons for the low level of diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH) in real clinical practice in a pandemic of a new coronavirus infection and possible ways to improve detection in patients with pulmonary embolism (PE) ) in history. The reasons for the low level of diagnosis of CTEPH are the insufficient level of knowledge of specialists, especially primary care physicians; lack of clear regulatory documents and expert centers for the management of this category of patients. Primary diagnosis of CTEPH in a pandemic can be strengthened through the widespread use of telemedicine for consultations of primary care physicians with specialists from expert centers; to maximize the role of echocardiography and computed tomography (CT) as differential diagnostic tools for dyspnea, in particular in patients with COVID-19. To increase the detection rate of CTEPH, diagnostic vigilance is required in patients with risk factors and episodes of venous thromboembolism. To improve the screening of CTEPH, it is necessary to create an algorithm for monitoring patients who have had PE; provide educational activities, including through the media; create materials for patients with accessible information. The regulatory documents should designate the circle of responsible specialists who will be engaged in long-term monitoring of patients with PE. Educational programs are needed for primary care physicians, cardiologists, and other physicians who come into the field of view of patients with CTEPH; introduction of a program to create expert centers for monitoring and managing patients with the possibility of performing ventilation-perfusion lung scintigraphy, cardiopulmonary stress test, CT, right heart catheterization. It seems important to build cooperation with the Ministry of Health of Russia in order to create special protocols, procedures for managing patients with PE and CTEPH.

Prognostic association between d-dimer thresholds and 30-day pulmonary embolism diagnosis among emergency department patients with suspected SARS-CoV-2 infection: a Canadian COVID-19 Emergency Department Rapid Response Network study.

OBJECTIVE: The primary objective was to quantify the prognostic association between various D-dimer thresholds and 30-day PE diagnosis among emergency department (ED) patients with suspected SARS-CoV-2 infection. METHODS: This was a retrospective study of patients enrolled in the Canadian COVID-19 ED Rapid Response Network (CCEDRRN) registry from March 1, 2020 to July 2, 2021. We included consecutive adults (≥ 18 years) presenting to 49 EDs with chest pain, shortness of breath, hypoxia, syncope, presyncope, or hemoptysis who were tested for both SARS-CoV-2 and D-dimer at index ED visit. The primary outcome measure was the sensitivity, specificity, and negative predictive value of D-dimer test thresholds for the outcome of 30-day PE diagnosis. RESULTS: Among 10,837 patients included in our study, 404 (3.7%) were diagnosed with PE at 30-days. A standard D-Dimer threshold of 500 ng/mL had a sensitivity of 97.8% (95% confidence interval [CI] 95.8-99.0%), specificity of 40.9% (95% CI 39.9-41.8%), and negative predictive value of 99.8% (95% CI 99.6-99.9%). An age-adjusted D-dimer threshold had a sensitivity of 96.0% (95% CI 93.6-97.7%), specificity of 48.5% (95% CI 47.5-49.4%), and negative predictive value of 99.7% (95% CI 99.5-99.8%). D-dimer testing had slightly lower prognostic performance among SARS-CoV-2 positive compared to SARS-CoV-2 negative patients in predicting 30-day PE diagnosis. CONCLUSIONS: Among ED patients with suspected SARS-CoV-2, the standard 500 ng/mL and age-adjusted D-dimer thresholds were comparable for the prediction of PE at 30-days. The prognostic performance of D-dimer was lower among SARS-CoV-2 positive patients. TRIAL REGISTRATION: Clinicaltrials.gov, NCT04702945.

RéSUMé: OBJECTIF: L'objectif principal était de quantifier l'association pronostique entre différents seuils de D-dimères et le diagnostic d'EP à 30 jours chez les patients des services d'urgence suspectés d'être infectés par le SRAS-CoV-2. MéTHODES: Il s'agissait d'une étude rétrospective des patients inscrits au registre du réseau canadien de réponse rapide aux urgences COVID-19 (CCEDRRN) du 1er mars 2020 au 2 juillet 2021. Nous avons inclus des adultes consécutifs (>18 ans) se présentant dans 49 services d'urgence pour une douleur thoracique, un essoufflement, une hypoxie, une syncope, une présyncope ou une hémoptysie et qui ont été testés à la fois pour le SRAS-CoV-2 et les D-dimères lors de la visite de référence aux urgences. Le principal critère d'évaluation était la sensibilité, la spécificité et la valeur prédictive négative des seuils du test des D-dimères pour le diagnostic de l'EP à 30 jours. RéSULTATS: Parmi les 10 837 patients inclus dans notre étude, 404 (3,7 %) ont reçu un diagnostic d'EP à 30 jours. Un seuil standard de D-Dimer de 500 ng/mL avait une sensibilité de 97,8 % (intervalle de confiance [IC] à 95 % 95,8-99,0 %), une spécificité de 40,9 % (IC à 95 % 39,9-41,8 %) et une valeur prédictive négative de 99,8 % (IC à 95 % 99,6-99,9 %). Un seuil de D-dimères ajusté à l'âge avait une sensibilité de 96,0% (IC à 95 % 93,6-97,7 %), une spécificité de 48,5% (IC à 95 % 47,5-49,4 %) et une valeur prédictive négative de 99,7 % (IC à 95 % 99,5-99,8 %). Le test des D-dimères avait une performance pronostique légèrement inférieure chez les patients positifs pour le SRAS-CoV-2 par rapport aux patients négatifs pour le SRAS-CoV-2 en ce qui concerne la prédiction du diagnostic d'EP à 30 jours. CONCLUSIONS: Chez les patients des urgences suspectés d'être atteints du SRAS-CoV-2, les seuils standard de 500 ng/ml et les seuils de D-dimères ajustés à l'âge étaient comparables pour la prédiction de l'EP à 30 jours. La performance pronostique des D-dimères était plus faible chez les patients positifs pour le SRAS-CoV-2. ENREGISTREMENT DE L'ESSAI: Clinicaltrials.gov, NCT04702945.

Pulmonary Embolism in COVID-19 Patients Is Not Related to a Deterioration of Tissue Oxygenation.

BACKGROUND: COVID-19 induces robust systemic inflammation. One of the main complications is the increased coagulation due to endotheliitis. There is an increased incidence of pulmonary embolism (PE) in COVID-19 patients. However, clinical characteristics for a strict analysis are yet to be determined. AIM: We evaluated oxygenation and characteristics in patients with COVID-19 PE (CPE). MATERIAL AND METHODS: We evaluated 215 COVID-19 patients from 1 January to 30 April 2021. We found 18 patients affected by PE (CPE, 50.0% males, aged 67.00 ± 10.86 years). As controls, we used data from patients affected by PE evaluated in our ward between 1 January 2015 and 31 December 2019 (64 patients, 53.1% males, aged 70.88 ± 16.44 years). All patients underwent a complete physical examination, pulmonary computerised tomography, laboratory tests, D-dimers and blood gas analysis at the time of diagnosis. RESULTS: There were no differences in laboratory tests nor in D-dimers between the two groups. In the CPE group we found a significantly increased pO2 (92.83 ± 42.52 vs. 76.11 ± 32.58 mmHg; p < 0.05), difference of oxygen between alveoli and arteries (A-aDO2; 169.3 ± 171.9 vs. 52.97 ± 39.65 mmHg; p < 0.05), and oxygen saturation % (97.06 ± 2.59 vs. 93.77 ± 5.53%; p < 0.05) compared to controls. No difference was found in pCO2 and the ratio between pO2 and percentage of inspired oxygen (P/F). Finally, a significantly decreased urate (3.67 ± 1.49 vs. 5.60 ± 2.10; p < 0.05) was found in CPE compared to controls. In CPE, platelets count presents an inverse correlation to P/F (r = -0.389, p = 0.02) but a direct correlation to A-aDO2 (r = 0.699, p = 0.001). No similar findings were present in controls. DISCUSSION: COVID-19 PE appears to have a different clinical setting. Reduced oxygenation described in PE may not to be considered as a sign of disease. The increased A-aDO2 may indicate that COVID-19 PE involved smaller vessels compared to classical PE. A possible diffuse capillary thrombosis could explain these results.

Pulmonary embolism response teams: Changing the paradigm in the care for acute pulmonary embolism.

Pulmonary embolism response teams (PERTs) have emerged as a multidisciplinary, multispecialty team of experts in the care of highly complex symptomatic acute pulmonary embolism (PE), with a centralized unique activation process, providing rapid multimodality assessment and risk stratification, formulating the best individualized diagnostic and therapeutic approach, streamlining the care in challenging clinical case scenarios (e.g., intermediate-high risk and high-risk PE), and facilitating the implementation of the recommended therapeutic strategies on time. PERTs are currently changing how complex acute PE cases are approached. The structure, organization, and function of a given PERT may vary from hospital to hospital, depending on local expertise, specific resources, and infrastructure for a given academic hospital center. Current emerging data demonstrate the value of PERTs in improving time to PE diagnosis; shorter time to initiation of anticoagulation reducing hospital length of stay; increasing use of advanced therapies without an increase in bleeding; and in some reports, decreasing mortality. Importantly, PERTs are positively impacting outcomes by changing the paradigm of care for acute PE through global adoption by the health-care community.

Veno-Arterial Extracorporeal Membrane Oxygenation and Thrombectomy for Massive Pulmonary Embolism.

Massive pulmonary embolism (PE) is associated with high mortality rates. Pulmonary Embolism Response Team (PERT) collaboration with prompt access to veno-arterial extracorporeal membrane oxygenation (VA ECMO) during mechanical or aspiration thrombectomy for massive PE can be life-saving; ECMO stand-by should be considered for high-risk cases. We describe a case of massive PE treated with intraprocedural VA ECMO during the catheter-directed intervention.

Editorial COVID-19 and Thrombosis 2023: New Waves of SARS-CoV-2 Infection, Triage Organization in Emergency Department and the Association of VOCs/VOI with Pulmonary Embolism.

Nearly two years ago, the SARS-CoV-2 outbreak began, and our lives have changed significantly since then [...].

Venous thromboembolism in COVID-19: A meta-summary of cases.

OBJECTIVES: To summarize cases of venous thromboembolism (VTE), including pulmonary embolism (PE) and deep vein thrombosis (DVT) among coronavirus disease (COVID-19) patients and discuss their symptoms, diagnostic method, clinical features, and prognosis. METHODS: All major databases were searched for relevant studies published between December 1, 2019 and May 5, 2021. RESULTS: A total of 233 articles were identified, 22 describing 48 patients were included. A total of 79.1% had PE and 20.9% had DVT. Most patients were men, with a mean age of 56 years. Comorbidities were present in 70.8%, and 85.4% had at least one risk factor of VTE. 56.3% had received anticoagulation therapy. Most patients were treated in the general ward. Complications occurred in 27.1% of the patients, and recovery was achieved in 80.4%. CONCLUSION: Venous thromboembolism must be suspected even in patients who had received prior anticoagulant regimens or in stable cases, especially in males, the elderly, and patients with comorbidities and high D-dimer levels.

D-dimer Thresholds to Exclude Pulmonary Embolism among COVID-19 Patients in the Emergency Department: Derivation with Independent Validation.

OBJECTIVE: To derive and validate a D-dimer cutoff for ruling out pulmonary embolism (PE) in COVID-19 patients presenting to the emergency department (ED). METHODS: A retrospective cohort study was performed in an integrated healthcare system including 22 adult ED's between March 1, 2020, and January 31, 2021. Results were validated among patients enrolled in the RECOVER Registry, representing data from 154 ED's from 26 US states. Consecutive ED patients with laboratory confirmed COVID-19, a D-dimer performed within 48 h of ED arrival, and with objectively confirmed PE were compared to those without PE. After identifying a D-dimer threshold at which the 95% confidence lower bound of the negative predictive value for PE was higher than 98% in the derivation cohort, it was validated using RECOVER registry data. RESULTS: Among 3978 patients with a D-dimer result, 3583 with confirmed COVID-19 infection were included in the derivation cohort. Overall, PE incidence was 4.1% and a D-dimer cutoff of <2 µ/mL (2000 ng/mL) was associated with a NPV of 98.5% (95% CI = 98.0%-98.9%). In the validation cohort of 13,091 patients with a D-dimer, 7748 had confirmed COVID-19 infection, and the PE incidence was 1.14%. A D-dimer cutoff of <2 µ/mL was associated with a NPV of 99.5% (95% CI = 99.3%-99.7%). CONCLUSION: A D-dimer cutoff of <2 µ/ml was associated with a high negative predictive value for PE among patients with COVID-19. However, the resultant sensitivity for PE result at that threshold without pre-test probability assessment would be considered clinically unsafe.