Development and Validation of a Simplified Probability Assessment Score Integrated With Age-Adjusted d-Dimer for Diagnosis of Acute Aortic Syndromes

Background

When acute aortic syndromes (AASs) are suspected, pretest clinical probability assessment and d‐dimer (DD) testing are diagnostic options allowing standardized care. Guidelines suggest use of a 12‐item/3‐category score (aortic dissection detection) and a DD cutoff of 500 ng/mL. However, a simplified assessment tool and a more specific DD cutoff could be advantageous.

Methods and Results

In a prospective derivation cohort (n=1848), 6 items identified by logistic regression (thoracic aortic aneurysm, severe pain, sudden pain, pulse deficit, neurologic deficit, hypotension), composed a simplified score (AORTAs) assigning 2 points to hypotension and 1 to the other items. AORTAs≤1 and ≥2 defined low and high clinical probability, respectively. Age‐adjusted DD was calculated as years/age × 10 ng/mL (minimum 500). The AORTAs score and AORTAs≤1/age‐adjusted DD rule were validated in 2 patient cohorts: a high‐prevalence retrospective cohort (n=1035; 22% AASs) and a low‐prevalence prospective cohort (n=447; 11% AASs) subjected to 30‐day follow‐up. The AUC of the AORTAs score was 0.729 versus 0.697 of the aortic dissection detection score (P=0.005). AORTAs score assessment reclassified 16.6% to 25.1% of patients, with significant net reclassification improvement of 10.3% to 32.7% for AASs and −8.6 to −17% for alternative diagnoses. In both cohorts, AORTAs≥2 had superior sensitivity and slightly lower specificity than aortic dissection detection ≥2. In the prospective validation cohort, AORTAs≤1/age‐adjusted DD had a sensitivity of 100%, a specificity of 48.6%, and an efficiency of 43.3%.

Conclusions

AORTAs is a simplified score with increased sensitivity, improved AAS classification, and minor trade‐off in specificity, amenable to integration with age‐adjusted DD for diagnostic rule‐out.

A case of non-severe COVID-19 complicated by pulmonary embolism

Novel coronavirus disease 2019 (COVID‐19) caused by severe acute respiratory syndrome coronavirus 2 is rapidly spreading worldwide. A typical clinical manifestation of COVID‐19 is pneumonia, which can progress to acute respiratory distress syndrome and respiratory failure. Recent studies have reported that COVID‐19 is often accompanied by coagulopathy, and a significant number of patients with severe or critical COVID‐19 develop concomitant thrombosis, including pulmonary embolism (PE). However, there are limited reports of the incidence of PE in non‐severe COVID‐19 patients. Here, we report a case of non‐severe COVID‐19 complicated by PE, which indicates that the possibility of PE should consistently be considered, even in non‐severe cases of COVID‐19 without any risk of thrombosis.

Clinical analysis of preoperative deep vein thrombosis risk factors in patients with colorectal cancer: Retrospective observational study

AIM

Deep vein thrombosis (DVT) is a major complication of cancer. The postoperative prevalence of DVT in colorectal cancer (CRC) surgery is high, but the preoperative prevalence and the risk factors have not been clarified in detail. The objective of this retrospective study was to investigate the preoperative prevalence and risk factors of DVT in patients admitted to hospital for CRC surgery.

METHODS

From January 2013 to March 2017, 1006 patients admitted for CRC surgery were deemed eligible for this retrospective study. Diagnosis of preoperative DVT was confirmed by compression ultrasonography. Prevalence of silent DVT in lower limbs in patients before CRC surgery was assessed, and the risk factors for preoperative DVT were investigated regarding the correlation of DVT with the patient's background.

RESULTS

Preoperative DVT and asymptomatic pulmonary thromboembolism were diagnosed in 136 (13.5%) and in 10 (1.0%) of 1006 patients overall, respectively. Multivariate analysis showed that increased age (≥75 years), female gender, and an elevated d-dimer level (>1.0 μg/mL) were independent risk factors for preoperative DVT in this study. Notably, the prevalence of preoperative DVT exceeded 50% in patients with all three predictors.

CONCLUSIONS

A high prevalence (13.5%) of preoperative DVT was found in patients admitted to the hospital for CRC surgery. The present results suggest that instrumental screening should be encouraged, at least in subgroups at a higher risk of preoperative DVT.

D-dimer levels over time and the risk of recurrent venous thromboembolism: an update of the Vienna prediction model

Background

Patients with unprovoked venous thromboembolism (VTE) can be stratified according to their recurrence risk based on their sex, the VTE location, and d‐dimer measured 3 weeks after anticoagulation by the Vienna Prediction Model. We aimed to expand the model to also assess the recurrence risk from later points on.

Methods and Results

Five hundred and fifty‐three patients with a first VTE were followed for a median of 68 months. We excluded patients with VTE provoked by a transient risk factor or female hormone intake, with a natural inhibitor deficiency, the lupus anticoagulant, or cancer. The study end point was recurrent VTE, which occurred in 150 patients. d‐Dimer levels did not substantially increase over time. Subdistribution hazard ratios (95% confidence intervals) dynamically changed from 2.43 (1.57 to 3.77) at 3 weeks to 2.27 (1.48 to 3.48), 1.98 (1.30 to 3.02) , and 1.73 (1.11 to 2.69) at 3, 9, and 15 months in men versus women, from 1.84 (1.00 to 3.43) to 1.68 (0.91 to 3.10), 1.49 (0.79 to 2.81) , and 1.44 (0.76 to 2.72) in patients with proximal deep vein thrombosis or pulmonary embolism compared with calf vein thrombosis, and from 1.30 (1.07 to 1.58) to 1.27 (1.06 to 1.51), 1.20 (1.02 to 1.41), and 1.13 (0.95 to 1.36) per doubling d‐dimer. Using a dynamic landmark competing risks regression approach, we generated nomograms and a web‐based calculator to calculate risk scores and recurrence rates from multiple times after anticoagulation.

Conclusions

Risk of recurrent VTE after discontinuation of anticoagulation can be predicted from multiple random time points by integrating the patient's sex, location of first VTE, and serial d‐dimer measurements.

D-dimer and its relationship to fibrinogen/fibrin degradation products (FDPs) in disorders associated with activation of coagulation or fibrinolytic systems

Levels of D-dimer and fibrinogen/fibrin degradation products (FDPs) are significantly elevated in patients with deep venous thrombosis, pulmonary embolism, disseminated intravascular coagulation, or other complications. The diagnosis of these disorders can be difficult, time-consuming, and expensive. Assays for the detection of FDPs and D-dimer are used in many laboratories to investigate these disorders. The aim of this study was to compare plasma D-dimer levels obtained by the immuno-turdimetric method (Liatest D-Dimer Diagnostica Stago, Asnières, France) with plasma FDPs were measured by latex agglutination to investigate the relationship between these parameters. These immunoassays were tested in 144 blood samples from patients with suspected disorders associated with activation of coagulation or fibrinolytic systems. D-dimer and FDPs assays were performed in plasma samples by the use of Liatest D-dimer and plasma FDPs (Diagnostica Stago), respectively. Patients were divided into four groups according to plasma D-dimer levels. In group 1, 47.4% had negative FDPs and 52.6% had positive FDPs. In group 2, 15.4% had negative FDPs and 84.6% had positive FDPs. In group 3, 10.3% had negative FDPs and 89.7% had positive FDPs. All of the patients in group 4 had positive FDPs. It was shown that plasma D-dimer levels measured by Liatest D-dimer have a relation to FDP levels measured by latex agglutination.