A higher D-dimer threshold for predicting pulmonary embolism in patients with COVID-19: a retrospective study

Non-Invasive Ventilation Support during Hospitalization for SARS-CoV-2 and the Risk of Venous Thromboembolism

Background/Objectives: Although SARS-CoV-2 infection is a significant risk factor for venous thromboembolism (VTE), data on the impact of the use of non-invasive ventilation support (NIVS) to mitigate the risk of VTE during hospitalization are scarce. Methods: Data for 1471 SARS-CoV-2 patients, hospitalized in a single hub during the first pandemic wave, were collected from clinical records, including symptom duration and type, information on lung abnormalities on chest computed tomography (CT), laboratory parameters and the use of NIVS. Determining VTE occurrence during hospital stays was the main endpoint. Results: Patients with VTE (1.8%) had an increased prevalence of obesity (26% vs. 11%), diabetes (41% vs. 21%), higher CHA2DS2VASC score (4, IQR 2-5 vs. 3, IQR 1-4, age- and sex-adjusted, p = 0.021) and cough (65% vs. 44%) and experienced significantly higher rates of NIVS (44% vs. 8%). Using a stepwise multivariate logistic regression model, the prevalence of electrocardiogram abnormalities (odds ratio (OR) 2.722, 95% confidence interval (CI) 1.039-7.133, p = 0.042), cough (OR 3.019, 95% CI 1.265-7.202, p = 0.013), CHA2DS2-VASC score > 3 (OR 3.404, 95% CI 1.362-8.513, p = 0.009) and the use of NIVS (OR 15.530, 95% CI 6.244-38.627, p < 0.001) were independently associated with a risk of VTE during hospitalization. NIVS remained an independent risk factor for VTE even after adjustment for the period of admission within the pandemic wave. Conclusions: Our study suggests that NIVS is a risk factor for VTE during hospitalization in SARS-CoV-2 patients. Future studies should assess the optimal prophylactic strategy against VTE in patients with a SARS-CoV-2 infection candidate to non-invasive ventilatory support.

An optimized D-dimer cut-off value to predict pulmonary thromboembolism in COVID-19 patients

Pulmonary thromboembolism (PTE) is a common complication in coronavirus disease 2019 (COVID-19) patients. Elevated D-dimer levels are observed even in the absence of PTE, reducing its discriminative ability as a screening test. It is unknown whether conventional D-dimer cut-off values, as used in the YEARS algorithm, apply to COVID-19 patients. This study aimed to determine the optimal D-dimer cut-off value to predict PTE in COVID-19 patients. All confirmed COVID-19 patients with a computed tomography pulmonary angiography (CTPA) performed ≤5 days after admission due to suspicion of PTE between March 2020 and February 2021, at Medisch Spectrum Twente, The Netherlands, were retrospectively analyzed. The association between PTE and D-dimer levels prior to CTPA, and other potential predictors, was analyzed using logistic regression analyses. The optimal cut-off value was identified using receiver operating characteristic (ROC) curve analyses. In 142 patients, PTE prevalence was 20.4%. The optimal cut-off value was 750 ng/mL (sensitivity 100%; specificity 19.5%; negative predictive value 100%; positive predictive value 24.2%). In total, 15 of 113 (13%) patients without PTE had a D-dimer level ≥500 and <750 ng/mL. In our population of patients hospitalized with COVID-19, a D-dimer level <750 ng/mL safely excluded PTE. Compared to the YEARS 500 ng/mL cut-off value, 13% fewer patients are in need of a CTPA, with similar sensitivity. Future research is required for external validation.

Effect of Anticoagulants in Pulmonary Thromboembolism in Post-COVID-19 Patients

Background and objective COVID-19 may predispose to both venous and arterial thromboembolism (VTE and ATE) due to excessive inflammation, immobilization, and hypoxia. The purpose of this study is to evaluate clinical and laboratory risk factors, as well as related medications such as anticoagulants, to predict the risk of thromboembolic disease and/or death in COVID-19 patients. Methods Over a period of 14 months (from August 2020 to September 2021), a total of 145 consecutive patients with signs and symptoms suspicious of pulmonary embolism (PE) were referred for perfusion single-photon emission computed tomography/computed tomography (Q SPECT/CT). All patients had a history of SARS‑CoV‑2 infection, diagnosed with a positive real-time polymerase chain reaction (RT-PCR) test. Results Among the 145 patients included in the study, the risk of PE was found to be greater in elderly patients (odds ratio [OR] [95% CI]: 1.05 [1.02‑1.07]; p<0.001) and in patients with higher maximum d-dimer levels (OR [95% CI]: 1.14 [1.01‑1.3]; p=0.04). We also analyzed the utility of the maximum d-dimer level for predicting acute PE with receiver operating characteristic (ROC) curve analysis. For d‑dimer = 0.5 mg/dL, cut-off sensitivity is 91%, specificity is 23%, and for d-dimer = 1 mg/dL, cut-off sensitivity is 79%, specificity is 43% Conclusion D-dimer titers were higher in the PE group in our study. Another significant finding was that, possibly due to thromboinflammation, anticoagulants did not prevent the development of PE in COVID-19 patients.

Pulmonary CT angiography in the first wave of the COVID-19 pandemic: Comparison between patients with and without infection and with a pre-pandemic series

BACKGROUND AND AIMS

To analyze the diagnostic performance of pulmonary CT angiography and to compare different D-dimer cutoffs for the diagnosis of acute pulmonary embolism in patients with and without SARS-CoV-2 infections.

MATERIALS AND METHODS

We retrospectively analysed all consecutive pulmonary CT angiography studies done for suspected pulmonary embolism in a tertiary hospital during two time periods: the first December 2020 through February 2021 and the second December 2017 through February 2018. D-dimer levels were obtained less than 24 h before the pulmonary CT angiography studies. We analysed the sensitivity, specificity, positive and negative predictive values, area under the receiver operating curve (AUC), and pattern of pulmonary embolism for six different values of D-dimer and the extent of the embolism. During the pandemic period, we also analysed whether the patients had COVID-19.

RESULTS

After excluding 29 poor-quality studies, 492 studies were analysed; 352 of these were done during the pandemic, 180 in patients with COVID-19 and 172 in patients without COVID-19. The absolute frequency of pulmonary embolism diagnosed was higher during the pandemic period (34 cases during the prior period and 85 during the pandemic; 47 of these patients had COVID-19). No significant differences were found in comparing the AUCs for the D-dimer values. The optimum values calculated for the receiver operating characteristic curves differed between patients with COVID-19 (2200 mcg/l), without COVID-19 (4800 mcg/l), and diagnosed in the prepandemic period (3200 mcg/l). Peripheral distribution of the emboli was more common in patients with COVID-19 (72%) than in those without COVID-19 and than in those diagnosed before the pandemic [OR 6.6, 95% CI: 1.5-24.6, p < 0.05 when compared to central distribution].

CONCLUSIONS

The number of CT angiography studies and the number of pulmonary embolisms diagnosed during the pandemic increased due to SARS-CoV-2 infection. The optimal d-dimer cutoffs and the distribution of the pulmonary embolisms differed between the groups of patients with and without COVID-19.

Role of Combined CT Pulmonary Angiography and Indirect CT Venography in Diagnosing Venous Thromboembolism in COVID-19 Patients - Experience From an Indian Quaternary Centre

OBJECTIVES

To study the role of combined CTPA and indirect CT venogram to diagnose venous thromboembolism (VTE) in patients with COVID-19 pneumonia and to compare the clinical characteristics, laboratory parameters, CT findings and clinical outcomes between the VTE positive and negative groups.

METHODS

In this retrospective study, 131 patients with COVID-19 pneumonia who underwent CTPA and venogram between August 2020 and January 2021 were included. Relevant demographical, clinical and laboratory data and CT images were collected. Two thoracic radiologists independently reviewed the CTPA and venogram images.

RESULTS

VTE was identified in 29 patients (22% of the study population). CT venogram identified DVT in 9 patients. No statistical difference was observed between the two groups with respect to age, gender, BMI and presence of comorbidities. There was a significant difference in the hospital stay duration, which is increased in the VTE positive group. The number of patients who were dependent on oxygen and mortality were also high in the positive group. There was statistically significant difference in the mean D-dimer value and the mean Neutrophil/lymphocyte ratio, which were higher in the VTE positive group.

CONCLUSION

Combined CTPA and venogram can be used as a one-stop investigation for diagnosing PE and DVT of lower limbs in patients with COVID-19 pneumonia. CTPA with venogram should be performed in patients with D-dimer value in the range of 1000 - 1200 μg/L and above to rule out VTE as the hospital stay duration and final outcomes vary between the positive and negative groups.

Changing face of pulmonary embolism with COVID-19

AIM

This study aimed to describe the baseline characteristics of coronavirus disease 2019 (COVID-19) patients with pulmonary embolism, and to examine the Geneva score, pulmonary embolism severity index (PESI), radiological and biochemical findings.

METHODS

From March 2020 to June 2021, the files of 41 COVID-19 patients with pulmonary embolism were accessed.

RESULTS

Mean D-dimer value was 6.04 mg/dl and 61% of the patients received at least one dose of anticoagulant treatment. In patients receiving deep venous thrombosis prophlaxis, an optimal D-dimer cut-off point was calculated as 5.69 mg/dl. The area under the curve was 0.753 (p = 0.007; sensivity 64%; specificity 62.5%). The mean Geneva score was 4.31, mean PESI was 72.48 and mean Qanadli score was 11.29.

CONCLUSIONS

According to this study, traditional clinical predictive scores had little discriminatory power in these patients, and a higher D-dimer cut-off value should be considered to better diagnose patients for pulmonary embolism.

Systematic screening versus clinical gestalt in the diagnosis of pulmonary embolism in COVID-19 patients in the emergency department

BACKGROUND

Diagnosing concomitant pulmonary embolism (PE) in COVID-19 patients remains challenging. As such, PE may be overlooked. We compared the diagnostic yield of systematic PE-screening based on the YEARS-algorithm to PE-screening based on clinical gestalt in emergency department (ED) patients with COVID-19.

METHODS

We included all ED patients who were admitted because of COVID-19 between March 2020 and February 2021. Patients already receiving anticoagulant treatment were excluded. Up to April 7, 2020, the decision to perform CT-pulmonary angiography (CTPA) was based on physician's clinical gestalt (clinical gestalt cohort). From April 7 onwards, systematic PE-screening was performed by CTPA if D-dimer level was ≥1000 ug/L, or ≥500 ug/L in case of ≥1 YEARS-item (systematic screening cohort).

RESULTS

1095 ED patients with COVID-19 were admitted. After applying exclusion criteria, 289 were included in the clinical gestalt and 574 in the systematic screening cohort. The number of PE diagnoses was significantly higher in the systematic screening cohort compared to the clinical gestalt cohort: 8.2% vs. 1.0% (3/289 vs. 47/574; p<0.001), even after adjustment for differences in patient characteristics (adjusted OR 8.45 (95%CI 2.61-27.42, p<0.001) for PE diagnosis). In multivariate analysis, D-dimer (OR 1.09 per 1000 μg/L increase, 95%CI 1.06-1.13, p<0.001) and CRP >100 mg/L (OR 2.78, 95%CI 1.37-5.66, p = 0.005) were independently associated with PE.

CONCLUSION

In ED patients with COVID-19, the number of PE diagnosis was significantly higher in the cohort that underwent systematic PE screening based on the YEARS-algorithm in comparison with the clinical gestalt cohort, with a number needed to test of 7.1 CTPAs to detect one PE.

Advanced Imaging Supports the Mechanistic Role of Autoimmunity and Plaque Rupture in COVID-19 Heart Involvement

The cardiovascular system is frequently affected by coronavirus disease-19 (COVID-19), particularly in hospitalized cases, and these manifestations are associated with a worse prognosis. Most commonly, heart involvement is represented by myocarditis, myocardial infarction, and pulmonary embolism, while arrhythmias, heart valve damage, and pericarditis are less frequent. While the clinical suspicion is necessary for a prompt disease recognition, imaging allows the early detection of cardiovascular complications in patients with COVID-19. The combination of cardiothoracic approaches has been proposed for advanced imaging techniques, i.e., CT scan and MRI, for a simultaneous evaluation of cardiovascular structures, pulmonary arteries, and lung parenchyma. Several mechanisms have been proposed to explain the cardiovascular injury, and among these, it is established that the host immune system is responsible for the aberrant response characterizing severe COVID-19 and inducing organ-specific injury. We illustrate novel evidence to support the hypothesis that molecular mimicry may be the immunological mechanism for myocarditis in COVID-19. The present article provides a comprehensive review of the available evidence of the immune mechanisms of the COVID-19 cardiovascular injury and the imaging tools to be used in the diagnostic workup. As some of these techniques cannot be implemented for general screening of all cases, we critically discuss the need to maximize the sustainability and the specificity of the proposed tests while illustrating the findings of some paradigmatic cases.

COVID-19 and Pulmonary Thrombosis-An Unresolved Clinical Puzzle: A Single-Center Cohort Study

Pulmonary thrombosis (PT) is a frequent complication of COVID-19. However, the risk factors, predictive scores, and precise diagnostic guidelines on indications for CT pulmonary angiography (CTPA) are still lacking. This study aimed to analyze the clinical and laboratory characteristics associated with PT in patients with COVID-19. We conducted a cohort study of consecutively hospitalized adult patients with COVID-19 who underwent CTPA at the University Hospital for Infectious Diseases in Zagreb, Croatia between 1 April and 31 December 2021. Of 2078 hospitalized patients, 575 (27.6%) underwent CTPA. PT was diagnosed in 178 (30.9%) patients (69.6% males, median age of 61, IQR 50-69 years). The PT group had a higher CRP, LDH, D-dimer, platelets, and CHOD score. PT was more frequent in patients requiring ≥15 L O₂/min (25.0% vs. 39.7%). In multivariable analysis, only D-dimer ≥ 1.0 mg/L (OR 1.78, 95%CI 1.12-2.75) and O₂ ≥ 15 L (OR 1.89, 95%CI 1.26-2.84) were associated with PT. PT was not associated with in-hospital mortality. In conclusion, our data confirmed a high incidence of PT in hospitalized patients with COVID-19, however, no correlation with traditional risk factors and mortality was found. CTPA should be performed in patients requiring high-flow supplemental oxygen or those with increased D-dimer levels.

Risk factors and mortality of pulmonary embolism in COVID-19 patients: Evidence based on fifty observational studies

BACKGROUND

At present, many studies have described acute pulmonary embolism (PE) as a frequent and prognostically relevant complication of coronavirus disease 2019 (COVID-19) infection. Thus we performed the present analysis of 50 studies to evaluate the risk factors and mortality of PE in COVID-19 patients.

METHOD

Databases including PubMed, Embase, Cochrane Library and Web of Science were searched to October, 2021. Odds ratio (OR), mean difference (MD) or standard MD was used to evaluate the outcomes. The primary outcomes were the difference of mortality between PE and non-PE COVID-19 patients as well as relevant risk factors of PE in COVID-19 patients. All statistical analyses were performed using the standard statistical procedures provided in Review Manager 5.2.

RESULT

A total of 50 studies including 10053 patients were included in this meta-analysis. Our results indicated that COVID-19 patients with PE experienced significantly higher mortality than non-PE patients (21.9% vs. 10.7%), with a pooled OR of 2.21 (95% CI 1.30 - 3.76; P = .003). In addition, COVID-19 patients with PE also experienced more mechanical ventilation (MV) (OR 2.21; 95% CI 1.30 - 3.75; P = .003) and invasive mechanical ventilation (IMV) (OR 3.58; 95% CI 2.47 - 5.20; P < .0001) respectively. Univariate analysis (UVA) results indicated the Sequential Organ Failure Assessment (SOFA) score, time to deep venous thrombosis (DVT), nonintensive care unit (non-ICU) patients and no anticoagulation as risk factors of PE for COVID-19 patients. In addition, multivariate analysis also found that SOFA score, D-dimer, BMI > 30 kg/m2 and history of PE were risk factors of PE for COVID-19 patients.

CONCLUSION

The present analysis indicated that PE increased the mortality of COVID-19 patients. Mechanical ventilation, especially invasive mechanical ventilation, is correlated with an increased incidence of PE in patients with COVID-19. The incidence of PE for COVID-19 patients may be multifactorial and further researches focused on risk factors were needed in the future.

Pulmonary embolism in patients with COVID-19 and D-dimer diagnostic value: A retrospective study

BACKGROUND

D-dimer levels are significantly higher in COVID-19 patients with Pulmonary Thromboembolism (PTE) as compared to those without PTE, but its clinical utility is still uncertain.

PURPOSE

To determine the D-dimer performance for ruling out PTE in patients with COVID-19. We also assessed clinical and laboratory factors associated with the presence of PTE on CT Pulmonary Angiogram (CTPA).

METHODS

Retrospective study involving all patients who presented at a tertiary care hospital from March 2020 to May 2021 with severe acute respiratory syndrome from COVID-19, who underwent CTPA and had D-dimer collected within 48 hours from CTPA. The D-dimer ability to classify patients with or without PTE according to CTPA was evaluated.

RESULTS

A total of 697 patients [382 (54.8%) men; mean (SD) age, 59 (20.5) years] were included, of which 71.5% required intensive care admission, 32.4% had PTE, and 35.6% died during hospitalization. PTE was independently associated with mortality [42.5% vs. 32.3%; p = 0.038]. D-dimer levels were higher in patients with PTE [9.1 (3.9; 20) vs. 2.3 (1.2; 5.1); p < 0.001]. Using the D-dimer cutoff of 0.5 μg/mL or above, sensitivity was 98.2% and specificity 5.7%. The 0.3 μg/mL threshold was associated with 100% of sensitivity for the presence of PTE, with which 99.1% of patients had increased values. ROC curve AUC was 0.77, demonstrating moderate discriminative power of D-dimers to detect PTE.

CONCLUSIONS

D-dimer levels are higher among COVID-19 hospitalized patients with PTE as compared to those without PTE and have moderate discriminative power to detect PTE, but its use to exclude PTE in this population may have limited clinical utility.

Managing two waves of the COVID-19 pandemic in northern emergency departments in Paris: COVIDORG II

Context

Objective

Methods

Results

Conclusion

A systematic review of biomarkers among hospitalized patients with COVID-19 predictive of venous thromboembolism: A communication from the Predictive and Diagnostic Variables Scientific and Standardization Committee of the ISTH

Background

Thrombosis is reported to occur more often among patients with COVID‐19 than otherwise expected in the setting of viral pneumonia and sepsis. Systemic inflammatory biomarkers may be associated with venous thromboembolism (VTE) risk. The ISTH subcommittee on Predictive and Diagnostic Variables in Thrombotic Disease aimed to report the evidence on prognostic biomarkers for VTE in hospitalized patients with COVID‐19.

Methods

Using a standardized Preferred Reporting Items for Systematic Reviews and Meta‐analysis methodology, we conducted a systematic literature review to identify studies reporting prognostic biomarkers for VTE among hospitalized patients with COVID‐19. Eligible studies included adults hospitalized with COVID‐19 and reported the prognostic associations between any biomarker measured on admission, and the subsequent diagnosis of deep vein thrombosis or pulmonary embolism. Two authors reviewed titles and abstracts, and three authors extracted study data and performed review of bias. Results were displayed descriptively. Meta‐analysis was not possible.

Results

From the initial 196 identified studies, full‐text review was performed for 72 studies. Admission D‐dimer levels were associated with VTE during hospitalization in five studies, and elevated platelet count was associated with VTE during hospitalization in one study. The risk of bias ranged from low to high for included studies. Overall, there was a paucity of high‐quality prognostic studies. Studies on other biomarkers did not meet the systematic review inclusion criteria.

Conclusions

Admission D‐dimer was associated with VTE diagnosis during hospitalization for COVID‐19; however, prospective validation of this finding is needed to identify optimal D‐dimer thresholds to guide VTE prophylaxis measures.

Examining D-dimer and Empiric Anti-coagulation in COVID-19-Related Thrombosis

Objective

Thrombosis is thought to occur frequently in the setting of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We aimed to elucidate the relationship between macro/microvascular thrombosis, D-dimer levels, and empiric anticoagulation in coronavirus disease 2019 (COVID-19).

Methods

This was an exploratory prospective, single-site, observational study. Adult emergency department patients with COVID-19 requiring hospitalization received a point-of-care lower extremity venous duplex ultrasound. The primary endpoint was thromboembolism and associated D-dimer level. Secondary endpoints included rates of micro and macro thrombotic complications as well as empiric anticoagulant use.

Results

Between January 13^th and April 12^th 2021, 52 patients were enrolled. Median D-dimer at presentation was 650 ng/mL (range 250-10,000 ng/mL) among patients with negative duplex studies. During hospitalization, 18 patients underwent 20 additional studies assessing for venous thromboembolism (VTE). These studies yielded one deep vein thrombosis (DVT) diagnosis. Among patients with negative studies median D-dimer was 1,246 ng/mL (range 329-10,000 ng/mL). Two patients experienced microvascular complications. Seven patients were started on empiric full dose anticoagulation.

Conclusion

While VTE remains a major concern amongst patients with COVID-19, the normal D-dimer cut off of >500 ng/mL likely should not be used to initiate further VTE workup. Additionally, moderately elevated D-dimer did not correlate strongly with microvascular complications and may not be relevant in the decision to initiate empiric anticoagulation.

"Triple low" free-breathing CTPA protocol for patients with dyspnoea

AIM

To assess the performance of a "triple-low" free-breathing protocol for computed tomography pulmonary angiography (CTPA) evaluated on patients with dyspnoea and suspected pulmonary embolism and discuss its application in routine clinical practice for the study of the pulmonary parenchyma and vasculature.

MATERIAL AND METHODS

This study was conducted on a selected group of dyspnoeic patients referred for CTPA. The protocol was designed using fast free-breathing acquisition and a small, fixed volume (35 ml) of contrast agent in order to achieve a low-exposure dose. For each examination, radiodensity of the pulmonary trunk and ascending aorta, and the dose-length product (DLP) were recorded. A qualitative analysis was performed of pulmonary arterial enhancement and the pulmonary parenchyma.

RESULTS

This study included 134 patients. Contrast enhancement of the pulmonary arteries (409 ± 159 HU) was systematically >250 HU. The duration of acquisition ranged from 0.9 to 1.3 seconds for free-breathing imaging. The mean DLP was in the range of low-dose chest CT acquisitions (145 ± 73 mGy·cm). The analysis was deemed optimal in 90% (120/134) of cases for the pulmonary parenchyma. Sixty-nine per cent (92/134) of cases demonstrated homogeneous enhancement of the pulmonary arteries to the subsegmental level. Only 6% (8/134) of examinations were considered uninterpretable.

CONCLUSION

The present "triple-low" CTPA protocol allows convenient analysis of the pulmonary parenchyma and arteries without hindrance by respiratory motion artefacts in dyspnoeic patients.

Diagnostic Management of Acute Pulmonary Embolism in COVID-19 and Other Special Patient Populations

Venous thromboembolism (VTE), in particular acute pulmonary embolism (PE), has been shown to be a frequent and potentially fatal complication of coronavirus disease 2019 (COVID-19). In response to the observed thrombotic complications, a large number of studies has been devoted to the understanding and management of COVID-19-associated coagulopathy. Notably, only a limited number of mostly retrospective studies has focused on the optimal diagnostic strategy for suspected PE in COVID-19 patients. As in other special populations, the accuracy of diagnostic algorithms for PE-exclusion has been debated in this specific patient subgroup as the specificity of D-dimer assays and clinical decision rules (CDRs) may be lower than normal. From this viewpoint, we discuss the current state-of-the-art diagnostic algorithms for acute PE with a focus on patients with COVID-19 in the perspective of other special patient populations. Furthermore, we summarize current knowledge regarding the natural history of PE resolution with anticoagulant treatment in patients with COVID-19.

A retrospective review of CT pulmonary angiogram confirmed pulmonary emboli in COVID-19 patients admitted to Groote Schuur Hospital, Cape Town

Background

A high incidence of thromboembolic phenomena has been widely reported in patients with coronavirus disease 2019 (COVID-19) pneumonia. There is, however, a paucity of data detailing the incidence and characteristics of pulmonary emboli (PE) in COVID-19 patients in the South African setting.

Objectives

To describe the incidence and characteristics of PE confirmed by CT pulmonary angiogram (CTPA) in patients with COVID-19 pneumonia admitted to a tertiary hospital in the Western Cape, South Africa.

Methods

This was a retrospective-, descriptive study of all adult patients with COVID-19 pneumonia confirmed by polymerase chain reaction (PCR) undergoing CTPA for suspected PE while admitted to Groote Schuur Hospital. The study period was from 01 April 2020 to 30 September 2020.

Results

The study cohort consisted of 116 patients, 59% being female, of whom 29% were pregnant or in the postpartum period. The median age for both genders combined was 49.5 years. The overall incidence of PE was 19%, with 20% in our subset of pregnant and postpartum patients. The majority (64%) of PE’s were reported as being segmental in anatomical location.

Conclusion

The noteworthy cohort included patients with pulmonary tuberculosis (PTB), HIV as well as pregnant and postpartum patients. The overall incidence of PE was 19% with no significant differences in demographics, comorbidities or D-dimer levels between patients with or without PE. The importance of a high clinical index of suspicion together with the role of CTPA in diagnosing PE in hospitalised COVID-19 patients is emphasised.

Disseminated Intravascular Coagulation Score and Sepsis-induced Coagulopathy Score in Prediction of COVID-19 Severity: A Retrospective Analysis

Background

The novel disseminated intravascular coagulation (DIC) score (platelet count, prolonged prothrombin time, D-dimer, and fibrinogen) and sepsis-induced coagulopathy (SIC) score (platelet count, international normalized ratio, and sequential organ failure assessment score) are markers of coagulopathy, which, for the first time, are explored in line with the coronavirus disease-2019 (COVID-19) disease outcomes. The correlation of D-dimer with these findings is also studied.

Materials and methods

A retrospective analysis of hospital-based records of 168 COVID-19 patients was done. Data including D-dimer, routine investigations, DIC, and SIC scorings (all within 3 days of admission) were collected and correlated with the outcomes. The study was conducted in a tertiary care center catering to North India's population.

Results

Higher DIC score (1.59 ± 1.18 vs 0.96 ± 1.18), SIC score (1.60 ± 0.89 vs 0.63 ± 0.99), and D-dimer titers (1321.33 ± 1627.89 vs 583·66 ± 777.71 ng/mL) were significantly associated with severe COVID-19 disease (p <0.05). DIC score and SIC score ≥1, and D-dimer ≥1315 ng/mL for severe disease; DIC score ≥1, SIC score ≥2, and D-dimer ≥600 ng/mL for pulmonary embolism (PE); and DIC score and SIC score ≥1, and D-dimer level ≥990 ng/mL for mortality were the respective cutoff values we found from our study.

Conclusion

Higher DIC scores, SIC scores, and D-dimer values are associated with severe COVID-19 disease, inhospital mortality, and PE risk. They can serve as easily accessible early markers of severe disease and prioritize hospital admissions in the presently overburdened scenario and may be used to develop prognostic prediction models.

How to cite this article

Kapoor M, Panda PK, Saini LK, Bahurupi Y. Disseminated Intravascular Coagulation Score and Sepsis-induced Coagulopathy Score in Prediction of COVID-19 Severity: A Retrospective Analysis. Indian J Crit Care Med 2021;25(12):1357–1363.

What level of D-dimers can safely exclude pulmonary embolism in COVID-19 patients presenting to the emergency department?

OBJECTIVES

To identify which level of D-dimer would allow the safe exclusion of pulmonary embolism (PE) in COVID-19 patients presenting to the emergency department (ED).

METHODS

This retrospective study was conducted on the COVID database of Assistance Publique - Hôpitaux de Paris (AP-HP). COVID-19 patients who presented at the ED of AP-HP hospitals between March 1 and May 15, 2020, and had CTPA following D-dimer dosage within 48h of presentation were included. The D-dimer sensitivity, specificity, and positive and negative predictive values were calculated for different D-dimer thresholds, as well as the false-negative and failure rates, and the number of CTPAs potentially avoided.

RESULTS

A total of 781 patients (mean age 62.0 years, 53.8% men) with positive RT-PCR for SARS-Cov-2 were included and 60 of them (7.7%) had CTPA-confirmed PE. Their median D-dimer level was significantly higher than that of patients without PE (4,013 vs 1,198 ng·mL^-1, p < 0.001). Using 500 ng·mL^-1, or an age-adjusted cut-off for patients > 50 years, the sensitivity and the NPV were above 90%. With these thresholds, 17.1% and 31.5% of CTPAs could have been avoided, respectively. Four of the 178 patients who had a D-dimer below the age-adjusted cutoff had PE, leading to an acceptable failure rate of 2.2%. Using higher D-dimer cut-offs could have avoided more CTPAs, but would have lowered the sensitivity and increased the failure rate.

CONCLUSION

The same D-Dimer thresholds as those validated in non-COVID outpatients should be used to safely rule out PE.

KEY POINTS

• The median D-dimer level was significantly higher in COVID-19 patients with PE as compared to those without PE (4,013 ng·mL^-1 vs 1,198 ng·mL^-1 respectively, p < 0.001). • Using 500 ng·mL^-1, or an age-adjusted D-dimer cut-off to exclude pulmonary embolism, the sensitivity and negative predictive value were above 90%. • Higher cut-offs would lead to a reduction in the sensitivity below 85% and an increase in the failure rate, especially for patients under 50 years.

A 10-fold and greater increase in D-dimer at admission in COVID-19 patients is highly predictive of pulmonary embolism in a retrospective cohort study

Background:

COVID-19 patients present with both elevated D-dimer and a higher incidence of pulmonary embolism (PE). This single-centre retrospective observational study investigated the prevalence of early PE in COVID-19 patients and its relation to D-dimer at presentation.

Methods:

The study included 1038 COVID-19-positive patients, with 1222 emergency department (ED) attendances over 11 weeks (16 March to 31 May 2020). Computed tomography pulmonary angiogram (CTPA) for PE was performed in 123 patients within 48 h of ED presentation, of whom 118 had D-dimer results. The remaining 875 attendances had D-dimer performed.

Results:

CTPA performed in 11.8% of patients within 48 h of ED presentation confirmed PE in 37.4% (46/123). Thrombosis was observed at all levels of pulmonary vasculature with and without right ventricular strain. In the CTPA cohort, patients with PE had significantly higher D-dimer, prothrombin time, C-reactive protein, troponin, total bilirubin, neutrophils, white cell count and lower albumin compared with non-PE patients. However, there was no difference in the median duration of inpatient stay or mortality. A receiver operator curve analysis demonstrated that D-dimer could discriminate between PE and non-PE COVID-19 patients (area under the curve of 0.79, p < 0.0001). Furthermore, 43% (n = 62/145) of patients with D-dimer >5000 ng/ml had CTPA with PE confirmed in 61% (n = 38/62), that is, 26% of >5000 ng/ml cohort. The sensitivity and specificity were related to D-dimer level; cutoffs of 2000, 3000, 4000, and 5000 ng/ml, respectively, had a sensitivity of 93%, 90%, 90% and 86%, and a specificity of 38%, 54%, 59% and 68%, and if implemented, an additional 229, 141, 106 and 83 CTPAs would be required.

Conclusion:

Our data suggested an increased PE prevalence in COVID-19 patients attending ED with an elevated D-dimer, and patients with levels >5000 ng/ml might benefit from CTPA to exclude concomitant PE.

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.

Diagnostic Accuracy of D-Dimers for Predicting Pulmonary Embolism in COVID-19-Patients

IMPORTANCE

Proinflammatory and hypercoagulable states with marked elevation seen in D-Dimer levels have been accurately described in patients infected by the SARS- Cov2 even without pulmonary embolism (PE).

OBJECTIVES

To compare D-dimers values in patients infected by the novel Coronavirus 2019 (COVID-19) with and without PE and to establish an optimal D-dimer cut-off to predict the occurrence of PE, which guides pulmonary computed tomography angiography (CTPA) indication.

METHODS

We retrospectively enrolled all COVID-19-patients admitted between October first and November 22th, 2020, at the University Hospital Center of Mohammed VI, Oujda (Morocco), suspected to have PE and underwent a CTPA. Demographic characteristics and blood test results were compared between PE-positive and PE-negative. The receiver operating characteristics (ROC) curve was constructed to establish an optimal D-Dimer cut-off to predict the occurrence of PE.

RESULTS

The study population consisted of 84 confirmed COVID-19-patients. The mean age was 64.93 years (SD 14.19). PE was diagnosed on CTPA in 31 (36.9%) patients. Clinical symptoms and in-hospital outcomes were similar in both groups except that more men had PE (p = .025). The median value of D-dimers in the group of patients with PE was significantly higher (14 680[IQR 33620-3450]ng/mL compared to the group of patients without PE 2980[IQR 6870-1600]ng/mL [P < .001]. A D-dimer at 2600 ng/mL was the optimal cut-off for predicting PE with a sensitivity of 90.3%, and AUC was .773[CI 95%, .667 -.876).

CONCLUSION

A D-dimer cut-off value of 2600 ng/mL is a significant predictor of PE in COVID-19-patients with a sensitivity of 90.3%.

Clinical and operational impact of rapid point-of-care SARS-CoV-2 detection in an emergency department

Study objective

Rapid point-of-care (POC) SARS-CoV-2 detection with Abbott ID NOW™ COVID-19 test has been implemented in our Emergency Department (ED) for several months. We aimed to evaluate the operational impact and potential benefits of this innovative clinical pathway.

Methods

We conducted a prospective, descriptive, interventional, non-randomized study, before-after trial with the comparison of patient cohorts from two consecutive periods of seven weeks (observational pre-POC period vs interventional POC period).

Results

In 2020, throughout weeks 37 to 50, 3333 patients were assessed for eligibility and among them 331 (9.9%) were positive for SARS-CoV-2 infections. Among the included patients, 136 (9.2%) were positive for SARS-CoV-2 infection in the pre-POC period and 195 (10.5%) in the POC period. Among positive patients for SARS-CoV-2 related infection in-hospital mortality rate was similar between the two groups but the hospitalization rate was higher in the POC group (81.6% vs. 65.4%; p < 0.001). More patients in the POC period were able to leave the ED within 6 h. We examined rates of antibiotic, anticoagulant, and corticosteroid prescriptions among patients tested for SARS-CoV-2 in the ED. Only the rate of prescribed anticoagulants was found to be higher in the POC period (40% vs. 24.2%; p < 0.003).

Conclusion

We demonstrated that COVID-19 point-of-care testing speeds up clinical decision-making, improving use of recommended treatments for COVID-19, such as anticoagulants. Moreover, it improves the boarding time and significantly shortened the length of stay in the ED for patients requiring outpatient care.

Impact of persistent D-dimer elevation following recovery from COVID-19

BACKGROUND

Elevated D-dimer is known as predictor for severity of SARS-CoV2-infection. Increased D-dimer is associated with thromboembolic complications, but it is also a direct consequence of the acute lung injury seen in COVID-19 pneumonia.

OBJECTIVES

To evaluate the rate of persistent elevated D-dimer and its association with thromboembolic complications and persistent ground glass opacities (GGO) after recovery from COVID-19.

METHODS

In this post hoc analysis of a prospective multicenter trial, patients underwent blood sampling, measurement of diffusion capacity, blood gas analysis, and multidetector computed tomography (MDCT) scan following COVID-19. In case of increased D-dimer (>0,5 μg/ml), an additional contrast medium-enhanced CT was performed in absence of contraindications. Results were compared between patients with persistent D-dimer elevation and patients with normal D-dimer level.

RESULTS

129 patients (median age 48.8 years; range 19-91 years) underwent D-Dimer assessment after a median (IQR) of 94 days (64-130) following COVID-19. D-dimer elevation was found in 15% (19/129) and was significantly more common in patients who had experienced a severe SARS-CoV2 infection that had required hospitalisation compared to patients with mild disease (p = 0.049). Contrast-medium CT (n = 15) revealed an acute pulmonary embolism in one patient and CTEPH in another patient. A significant lower mean pO2 (p = 0.015) and AaDO2 (p = 0.043) were observed in patients with persistent D-Dimer elevation, but the rate of GGO were similar in both patient groups (p = 0.33).

CONCLUSION

In 15% of the patients recovered from COVID-19, persistent D-dimer elevation was observed after a median of 3 months following COVID-19. These patients had experienced a more severe COVID and still presented more frequently a lower mean pO2 and AaDO2.

Risk factors for pulmonary embolism in patients with COVID-19: a systemic review and meta-analysis

PURPOSE

To detect the risk factors for pulmonary embolism (PE) in patients with COVID-19.

METHODS

Studies were searched for in PubMed, Cochrane Library, Web of Science, and EMBASE. Two authors independently screened articles and extracted data. The data were pooled by meta-analysis and three subgroup analyses were performed.

RESULTS

Of the 2210 articles identified, 27 studies were included. Pooled analysis suggested that males (odds ratio (OR) 1.49, 95% confidence interval (CI) 1.26-1.75, P = 0.000), obesity (OR 1.37, 95% CI 1.03-1.82, P = 0.033), mechanical ventilation (OR 3.34, 95% CI 1.90-5.86, P = 0.000), severe parenchymal abnormalities (OR 1.92, 95% CI 1.43-2.58, P = 0.000), ICU admission (OR 2.44, 95% CI 1.48-4.03, P = 0.000), and elevated D-dimer and white blood cell values (at two time points: hospital admission or closest to computed tomography pulmonary angiography) (P = 0.000) correlated with a risk for PE occurrence in COVID-19 patients. However, age and common comorbidities had no association with PE occurrence. Computed tomography pulmonary angiography, unclear-ratio/low-ratio, and hospitalization subgroups had consistent risk factors with all studies; however, other subgroups had fewer risk factors for PE.

CONCLUSIONS

Risk factors for PE in COVID-19 were different from the classic risk factors for PE and are likely to differ in diverse study populations.

The impact of COVID-19 on the sensitivity of D-dimer for pulmonary embolism

Objective

This study seeks to evaluate the test characteristics of D‐dimer for pulmonary embolism (PE) in patients with a concurrent diagnosis of COVID‐19. We hypothesized that the sensitivity of D‐dimer for PE at current institutional cut points would be similar to those without COVID‐19.

Methods

This is a multicenter retrospective observational cohort study across five urban and suburban EDs in the same health care system. The electronic health record was queried for all computed tomography pulmonary angiography (CTPA) studies from December 1, 2019, to October 22, 2020. All ED patients who underwent CTPA had D‐dimer and COVID‐19 testing completed in a single encounter were included in the study. Baseline demographics were obtained. Test characteristics of D‐dimer for PE were calculated for patients with and without COVID‐19. Additionally, receiver operator characteristics (ROC) curves were constructed for two different D‐dimer assays.

Results

There were 1158 patient encounters that met criteria for analysis. Performance of D‐dimer testing for PE was similar between COVID‐19–positive and –negative patients. In COVID‐19–positive patients, the sensitivity was 100% (95% confidence interval [CI] = 87.6%–100%), specificity was 11.9% (95% CI = 7.9%–17.1%), and negative predictive value (NPV) was 100%. In COVID‐19–negative patients the sensitivity was 97.6% (95% CI = 91.5%–99.7%), specificity was 14.4% (95% CI = 12.1%–17%), and NPV was 98.3% (95% CI = 93.8%–99.6%). For assay 1 the area under the curve (AUC) for COVID‐19–positive patients was 0.76 (95% CI = 0.68–0.83), and for COVID‐19–negative patients, 0.73 (95% CI = 0.69–0.77). For assay 2, AUC for COVID‐19–positive patients was 0.85 (95% CI = 0.77–0.92), and for COVID‐19–negative patients, 0.80 (95% CI = 0.77–0.84). Inspection of the ROC curve for assay 1 revealed that 100% sensitivity was maintained up to a threshold of 0.67 FEU (fibrinogen equivalent units; from 0.50 FEU) with an increase in specificity to 29% (from 18.7%), and for assay 2, 100% sensitivity was maintained up to a threshold of 662 D‐dimer units (DDU; from 230 DDU) with an increased specificity to 59% (from 6.1%).

Conclusion

Results from this multicenter retrospective study did not find a significant difference in sensitivity of D‐dimer for PE due to concomitant COVID‐19 infection. Further study is required to determine if PE can safely be excluded based on D‐dimer results alone in patients with suspected or proven COVID‐19 or if adjusted D‐dimer levels could have a role in management.

Pulmonary embolism and COVID-19: A comparative analysis of different diagnostic models performance

OBJECTIVE

Pulmonary embolism (PE) is a common complication of SARS-CoV-2 infection. Several diagnostic prediction rules based on pretest probability and D-dimer have been validated in non-COVID patients, but it remains unclear if they can be safely applied in COVID-19 patients. We aimed to compare the diagnostic accuracy of the standard approach based on Wells and Geneva scores combined with a standard D-dimer cut-off of 500 ng/mL with three alternative strategies (age-adjusted, YEARS and PEGeD algorithms) in COVID-19 patients.

METHODS

This retrospective study included all COVID-19 patients admitted to the Emergency Department (ED) who underwent computed tomography pulmonary angiography (CTPA) due to PE suspicion. The diagnostic prediction rules for PE were compared between patients with and without PE.

RESULTS

We included 300 patients and PE was confirmed in 15%. No differences were found regarding comorbidities, traditional risk factors for PE and signs and symptoms between patients with and without PE. Wells and Geneva scores showed no predictive value for PE occurrence, whether a standard or an age-adjusted cut-off was considered. YEARS and PEGeD algorithms were associated with increased specificity (19% CTPA reduction) but raising non-diagnosed PE. Despite elevated in all patients, those with PE had higher D-dimer levels. However, incrementing thresholds to select patients for CTPA was also associated with a substantial decrease in sensitivity.

CONCLUSION

None of the diagnostic prediction rules are reliable predictors of PE in COVID-19. Our data favour the use of a D-dimer threshold of 500 ng/mL, considering that higher thresholds increase specificity but limits this strategy as a screening test.

Ruling out Pulmonary Embolism in Patients with (Suspected) COVID-19-A Prospective Cohort Study

Background  Diagnostic strategies for suspected pulmonary embolism (PE) have not been prospectively evaluated in COVID-19 patients.

Methods  Prospective, multicenter, outcome study in 707 patients with both (suspected) COVID-19 and suspected PE in 14 hospitals. Patients on chronic anticoagulant therapy were excluded. Informed consent was obtained by opt-out approach. Patients were managed by validated diagnostic strategies for suspected PE. We evaluated the safety (3-month failure rate) and efficiency (number of computed tomography pulmonary angiographies [CTPAs] avoided) of the applied strategies.

Results  Overall PE prevalence was 28%. YEARS was applied in 36%, Wells rule in 4.2%, and “CTPA only” in 52%; 7.4% was not tested because of hemodynamic or respiratory instability. Within YEARS, PE was considered excluded without CTPA in 29%, of which one patient developed nonfatal PE during follow-up (failure rate 1.4%, 95% CI 0.04–7.8). One-hundred seventeen patients (46%) managed according to YEARS had a negative CTPA, of whom 10 were diagnosed with nonfatal venous thromboembolism (VTE) during follow-up (failure rate 8.8%, 95% CI 4.3–16). In patients managed by CTPA only, 66% had an initial negative CTPA, of whom eight patients were diagnosed with a nonfatal VTE during follow-up (failure rate 3.6%, 95% CI 1.6–7.0).

Conclusion  Our results underline the applicability of YEARS in (suspected) COVID-19 patients with suspected PE. CTPA could be avoided in 29% of patients managed by YEARS, with a low failure rate. The failure rate after a negative CTPA, used as a sole test or within YEARS, was non-negligible and reflects the high thrombotic risk in these patients, warranting ongoing vigilance.

Mortality and risk factors associated with pulmonary embolism in coronavirus disease 2019 patients: a systematic review and meta-analysis

To determine, in patients with coronavirus disease 2019 (COVID-19) infection, the associations of pulmonary embolism (PE) with mortality and risk factors for PE as well as the therapeutic benefit of anticoagulant prophylaxis. Embase, PubMed, Cochrane controlled trials register, and Web of Science databases were searched from inception to October 10, 2020. We included all published trials on PE in patients diagnosed with COVID-19 with eligibility of the trials assessed following the PRISMA guidelines. Sixteen clinical trials with 5826 patients were eligible. There were significant associations of PE with the male gender [odd ratio (OR) = 1.59, 95% CI 1.28-1.97], mechanical ventilation (OR = 3.71, 95% CI 2.57-5.36), intensive care unit admission (OR = 2.99, 95% CI 2.11-4.23), circulating D-dimer [mean difference (MD) = 5.04 µg/mL, 95% CI 3.67-6.42) and CRP (MD = 1.97 mg/dL, 95% CI 0.58- 3.35) concentrations without significant correlation between PE and mortality (OR = 1.31, 95% CI 0.82-2.08) as well as other parameters or comorbidities. After omitting one trial with strict patient selection criteria for anticoagulant prophylaxis, significant prophylactic benefit was noted (OR = 0.31, 95% CI 0.1-0.91). Our findings identified the risk factors associated with PE in COVID-19 patients and supported the therapeutic benefit of anticoagulant prophylaxis against PE in this patient population.

Venous thromboembolism in COVID-19: A systematic review and meta-analysis

Severe coronavirus disease 2019 (COVID-19) is associated with increased risk of venous thromboembolism events (VTE). This study performed a systematic review in PubMed/EMBASE of studies reporting the prevalence of VTE in patients with COVID-19 who were totally screened/assessed for deep vein thrombosis (DVT) and/or for pulmonary embolism (PE). Among 47 candidate studies (n = 6459; 33 in Europe), 17 studies (n = 3973; weighted age 63.0 years, males 60%, intensive care unit (ICU) 16%) reported the prevalence of PE with a pooled estimate of 32% (95% CI: 25, 40%), and 32 studies (n = 2552; weighted age 62.6 years, males 57%, ICU 49%) reported the prevalence of DVT with a pooled estimate of 27% (95% CI: 21, 34%). A total of 36 studies reported the use of at least prophylactic antithrombotic treatment in the majority of their patients. Meta-regression analysis showed that the prevalence of VTE was higher across studies with a higher percentage of ICU patients and higher study population mean D-dimer values, and lower in studies with mixed dosing of anticoagulation in ⩾ 50% of the population compared to studies with standard prophylactic dosing of anticoagulation in < 50% of the population. The pooled odds ratio for death in patients with COVID-19 and VTE versus those without VTE (17 studies, n = 2882) was 2.1 (95% CI: 1.2, 3.6). Hospitalized patients with severe COVID-19 are at high VTE risk despite prophylactic anticoagulation. Further research should investigate the individualized VTE risk of patients with COVID-19 and the optimal preventive antithrombotic therapy. PROSPERO Registration No.: CRD42020185543.

Relationship of D-dimer and prediction of pulmonary embolism in hospitalized COVID-19 patients: a multicenter study

Aim: COVID-19 is a known risk factor for pulmonary embolism (PE). In this retrospective, multicenter study, we aimed to determine an optimal D-dimer cutoff to predict PE in hospitalized patients with COVID-19. Materials & methods: A total of 193 patients underwent computerized tomographic pulmonary angiography imaging and were classified into PE positive and negative groups. Physiological, radiological and biochemical parameters were compared and receiver operator curve analysis was conducted to determine a predictive D-dimer threshold. Results: An optimal D-dimer cutoff of 2494 ng/ml was selected (Youden index: 0.906), giving a sensitivity of 100% (95% CI: 100–100) and specificity of 90.62% (95% CI: 90.5–90.8) for predicting PE. Conclusion: We propose that in the absence of other clinical signs, a D-dimer threshold of 2495 ng/ml could be used with high sensitivity and specificity to predict PE in hospitalized patients with COVID-19.

Investigation of perfusion defects by Q-SPECT/CT in patients with mild-to-moderate course of COVID-19 and low clinical probability for pulmonary embolism

Objective

Pulmonary embolism is a severe source of mortality and morbidity in patients with severe and critical coronavirus disease 2019. It is not yet clear whether the tendency to thrombosis is increased in the mild-to-moderate course of COVID-19. Our research aims to show the clinical benefit of Q-SPECT/CT in diagnosing PD in outpatients treated with mild-to-moderate course of COVID-19 and to determine the frequency of perfusion defects in these patients having relatively lower risk.

Methods

All patients who underwent Q-SPECT/CT with suspicion of embolism were examined retrospectively. Only patients with low clinical probability and mild-to-moderate course of COVID-19 for PE were included in the study. The patients were evaluated comparatively as those with and without perfusion defects. Patients were divided into laboratory suspicion, clinical suspicion, or clinical and laboratory suspicion.

Results

In outpatients with mild-to-moderate COVID-19 with low clinical probability for PE, PD without CT abnormality was detected with a rate of 36.6% with Q-SPECT/CT performed for complaints of high d-dimer and/or dyspnea. None of the patients had PD at more proximal level than the segment level. PD with no concomitant CT abnormality was observed with a rate of 56.5% in patients with both clinical and laboratory suspicion. For d-dimer = 0.5 mg/dL cut-off sensitivity is 85%, for d-dimer = 1.5 mg/dL cut-off specificity 81%.

Conclusion

Thrombosis tendency is also present in outpatients with mild-to-moderate COVID-19, and these patients should also be offered anticoagulant prophylaxis during the COVID-19 period.

Routine screening for pulmonary embolism in COVID-19 patients at the emergency department: impact of D-dimer testing followed by CTPA

COVID-19 patients have increased risk of pulmonary embolism (PE), but symptoms of both conditions overlap. Because screening algorithms for PE in COVID-19 patients are currently lacking, PE might be underdiagnosed. We evaluated a screening algorithm in which all patients presenting to the ED with suspected or confirmed COVID-19 routinely undergo D-dimer testing, followed by CT pulmonary angiography (CTPA) if D-dimer is ≥ 1.00 mg/L. Consecutive adult patients presenting to the ED of two university hospitals in Amsterdam, The Netherlands, between 01-10-2020 and 31-12-2020, who had a final diagnosis of COVID-19, were retrospectively included. D-dimer and CTPA results were obtained. Of 541 patients with a final diagnosis of COVID-19 presenting to the ED, 25 (4.6%) were excluded because D-dimer was missing, and 71 (13.1%) because they used anticoagulation therapy. Of 445 included patients, 185 (41.6%; 95%CI 37.0–46.3) had a D-dimer ≥ 1.00 mg/L. CTPA was performed in 169 of them, which showed PE in 26 (15.4%; 95%CI 10.3–21.7), resulting in an overall detection rate of 5.8% (95%CI 3.9–8.4) in the complete study group. In patients with and without PE at CTPA, median D-dimer was 9.84 (IQR 3.90–29.38) and 1.64 (IQR 1.17–3.01), respectively (p < 0.001). PE prevalence increased with increasing D-dimer, ranging from 1.2% (95%CI 0.0–6.4) if D-dimer was 1.00–1.99 mg/L, to 48.6% (95%CI 31.4–66.0) if D-dimer was ≥ 5.00 mg/L. In conclusion, by applying this screening algorithm, PE was identified in a considerable proportion of COVID-19 patients. Prospective management studies should assess if this algorithm safely rules-out PE if D-dimer is < 1.00 mg/L.

Role of combining anticoagulant and antiplatelet agents in COVID-19 treatment: a rapid review

Although primarily affecting the respiratory system, COVID-19 causes multiple organ damage. One of its grave consequences is a prothrombotic state that manifests as thrombotic, microthrombotic and thromboembolic events. Therefore, understanding the effect of antiplatelet and anticoagulation therapy in the context of COVID-19 treatment is important. The aim of this rapid review was to highlight the role of thrombosis in COVID-19 and to provide new insights on the use of antithrombotic therapy in its management. A rapid systematic review was performed using preferred reporting items for systematic reviews. Papers published in English on antithrombotic agent use and COVID-19 complications were eligible. Results showed that the use of anticoagulants increased survival and reduced thromboembolic events in patients. However, despite the use of anticoagulants, patients still suffered thrombotic events likely due to heparin resistance. Data on antiplatelet use in combination with anticoagulants in the setting of COVID-19 are quite scarce. Current side effects of anticoagulation therapy emphasise the need to update treatment guidelines. In this rapid review, we address a possible modulatory role of antiplatelet and anticoagulant combination against COVID-19 pathogenesis. This combination may be an effective form of adjuvant therapy against COVID-19 infection. However, further studies are needed to elucidate potential risks and benefits associated with this combination.

Correlations Between Covid 19 Symptoms and Risk of Pulmonary Embolism

The World Health Organization (WHO) declares COVID 19 pandemic in March 2020. Each pandemic wave had different clinical and biological characteristics, the expression of the disease being correlated with the dominant viral variant. Patients with COVID 19 have a pro-coagulant status, which predisposes them to thromboembolic complications.

The current study aims to systematize the symptoms of COVID 19 and to highlight its relationship with the suspicion and confirmation of the diagnosis of pulmonary thromboembolism.

We performed a descriptive retrospective study on patients with COVID 19 for a period of 4 months (September-December 2021). During this period, 183 were hospitalized with COVID 19 and 53 were enrolled in the study. Incidence of COVID 19 was 63% (33) in men and 37% for women. The average age of women was 68 years compared to men where the average age was 61 years. We observed a higher incidence of the disease in men in the 41–60 age group (39% of all men), while, in women, the most affected age group was 61–80 years (60% of all women). Pulmonary thromboembolism (PE) was diagnosed by pulmonary artery angiography, with an incidence of 57% in the study group affecting 60% of women and 55% of men.

The symptoms are dominated by fever, cough and dyspnea. Fever was present in 65% of women and 55% of men, cough was present in 65% of women and 79% of men, while dyspnea involved 40% of women and 42% of men.

In conclusion, PE was a common complication in COVID patients that contributed to adverse outcome and higher mortality. The symptoms were not specific to minor forms of the disease.

D-Dimer Level and Neutrophils Count as Predictive and Prognostic Factors of Pulmonary Embolism in Severe Non-ICU COVID-19 Patients

The incidence of pulmonary embolism (PE) is high during severe Coronavirus Disease 2019 (COVID-19). We aimed to identify predictive and prognostic factors of PE in non-ICU hospitalized COVID-19 patients. In the retrospective multicenter observational CLOTVID cohort, we enrolled patients with confirmed RT-PCR COVID-19 who were hospitalized in a medicine ward and also underwent a CT pulmonary angiography for a PE suspicion. Baseline data, laboratory biomarkers, treatments, and outcomes were collected. Predictive and prognostics factors of PE were identified by using logistic multivariate and by Cox regression models, respectively. A total of 174 patients were enrolled, among whom 86 (median [IQR] age of 66 years [55–77]) had post-admission PE suspicion, with 30/86 (34.9%) PE being confirmed. PE occurrence was independently associated with the lack of long-term anticoagulation or thromboprophylaxis (OR [95%CI], 72.3 [3.6–4384.8]) D-dimers ≥ 2000 ng/mL (26.3 [4.1–537.8]) and neutrophils ≥ 7.0 G/L (5.8 [1.4–29.5]). The presence of these two biomarkers was associated with a higher risk of PE (p = 0.0002) and death or ICU transfer (HR [95%CI], 12.9 [2.5–67.8], p < 0.01). In hospitalized non-ICU severe COVID-19 patients with clinical PE suspicion, the lack of anticoagulation, D-dimers ≥ 2000 ng/mL, neutrophils ≥ 7.0 G/L, and these two biomarkers combined might be useful predictive markers of PE and prognosis, respectively.

Assessment of pulmonary arterial circulation 3 months after hospitalization for SARS-CoV-2 pneumonia: Dual-energy CT (DECT) angiographic study in 55 patients

BACKGROUND

During COVID-19, the main manifestations of the disease are not only pneumonia but also coagulation disorders. The purpose of this study was to evaluate pulmonary vascular abnormalities 3 months after hospitalization for SARS-CoV-2 pneumonia in patients with persistent respiratory symptoms.

METHODS

Among the 320 patients who participated in a systematic follow-up 3 months after hospitalization, 76 patients had residual symptoms justifying a specialized follow-up in the department of pulmonology. Among them, dual-energy CT angiography (DECTA) was obtained in 55 patients.

FINDINGS

The 55 patients had partial (n = 40; 72.7%) or complete (n = 15; 27.3%) resolution of COVID-19 lung infiltration. DECTA was normal in 52 patients (52/55; 94.6%) and showed endoluminal filling defects in 3 patients (3/55; 5.4%) at the level of one (n = 1) and two (n = 1) segmental arteries of a single lobe and within central and peripheral arteries (n = 1). DECT lung perfusion was rated as non-interpretable (n = 2;3.6%), normal (n = 17; 30.9%) and abnormal (n = 36; 65.5%), the latter group comprising 32 patients with residual COVID-19 opacities (32/36; 89%) and 4 patients with normal lung parenchyma (4/36; 11%). Perfusion abnormalities consisted of (a) patchy defects (30/36; 83%), (b) PE-type defects (6/36; 16.6%) with (n = 1) or without proximal thrombosis (n = 5); and (c) focal areas of hypoperfusion (2/36; 5.5%). Increased perfusion was seen in 15 patients, always matching GGOs, bands and/or vascular tree-in- bud patterns.

INTERPRETATION

DECT depicted proximal arterial thrombosis in 5.4% of patients and perfusion abnormalities suggestive of widespread microangiopathy in 65.5% of patients. Lung microcirculation was abnormal in 4 patients with normal lung parenchyma.

Clinical characteristics and outcomes of venous thromboembolism in patients hospitalized for COVID-19: Systematic review and meta-analysis

Venous thromboembolism is prevalent in hospitalized COVID-19 patients. Through systematic review and meta-analysis, we have investigated the differences in clinical characteristics and outcome of hospitalized COVID-19 patients with (+) and without (-) venous thromboembolism (VTE). 45 studies with a total of 8859 patients were included in the qualitative synthesis. Subsequently, 38 studies with a total of 7847 patients, were quantitatively analyzed. There was no mortality difference between the VTE (-) and VTE (+) hospitalized COVID-19 patients (RR1.32 (0.97, 1.79); 0.07; I2 64%, p ​< ​0.001). Patients with VTE (+) were more likely to get admitted to the intensive care unit (RR1.77 (1.26, 2.50); p ​< ​0.001; I2 63%, p ​= ​0.03) and mechanically ventilated (RR 2.35 (1.22, 4.53); p ​= ​0.01; I2 88%, p ​< ​0.001). Moreover, male gender (RR 1.19 (1.14,1.24), p ​< ​0.001; I2 0%, p ​= ​0.68), increased the risk of VTE. Regarding patients lab values', VTE (+) was significantly associated with higher white blood cell, neutrophil count, D-Dimer, alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and C-reactive protein (CRP), along with prolonged prothrombin time. On the contrary, VTE (+) was associated with lower albumin and neutrophil-lymphocyte ratio (NLR). This findings provide the initial framework for risk stratification of hospitalized COVID-19 patients with VTE.

Pulmonary embolism in patients with COVID-19 and value of D-dimer assessment: a meta-analysis

PURPOSE

To investigate, in a meta-analysis, the frequency of pulmonary embolism (PE) in patients with COVID-19 and whether D-dimer assessment may be useful to select patients for computed tomography pulmonary angiography (CTPA).

METHODS

A systematic literature search was performed for original studies which reported the frequency of PE on CTPA in patients with COVID-19. The frequency of PE, the location of PE, and the standardized mean difference (SMD) of D-dimer levels between patients with and without PE were pooled by random effects models.

RESULTS

Seventy-one studies were included. Pooled frequencies of PE in patients with COVID-19 at the emergency department (ED), general wards, and intensive care unit (ICU) were 17.9% (95% CI: 12.0-23.8%), 23.9% (95% CI: 15.2-32.7%), and 48.6% (95% CI: 41.0-56.1%), respectively. PE was more commonly located in peripheral than in main pulmonary arteries (pooled frequency of 65.3% [95% CI: 60.0-70.1%] vs. 32.9% [95% CI: 26.7-39.0%]; OR = 3.540 [95% CI: 2.308-5.431%]). Patients with PE had significantly higher D-dimer levels (pooled SMD of 1.096 [95% CI, 0.844-1.349]). D-dimer cutoff levels which have been used to identify patients with PE varied between 1000 and 4800 μg/L.

CONCLUSION

The frequency of PE in patients with COVID-19 is highest in the ICU, followed by general wards and the ED. PE in COVID-19 is more commonly located in peripheral than in central pulmonary arteries, which suggests local thrombosis to play a major role. D-dimer assessment may help to select patients with COVID-19 for CTPA, using D-dimer cutoff levels of at least 1000 μg/L.

KEY POINTS

• The frequency of PE in patients with COVID-19 is highest in the ICU, followed by general wards and the ED. • PE in COVID-19 is more commonly located in peripheral than in central pulmonary arteries. • D-dimer levels are significantly higher in patients with COVID-19 who have PE.