Serum D-Dimer is a Sensitive Test for the Detection of Acute Aortic Dissection: A Pooled Meta-Analysis

The combined use of serum Raman spectroscopy and D dimer testing for the early diagnosis of acute aortic dissection

Objectives

Acute aortic dissection (AAD) is an extremely life-threatening medical emergency, often misdiagnosed in its early stages, resulting in prolonged wait times for rescue. This study aims to identify potential serum biomarkers that can assist in the accurate diagnosis of AAD and effectively differentiate it from other conditions causing severe chest pain.

Methods

A total of 122 patients with AAD and 129 patients with other severe chest pain disorders were included in the study. Serum samples were analyzed by measuring the peak intensities of Raman spectra. For each measurement, the Raman spectrum was accumulated by two accumulations (3 s per acquisition). Logistic regression and nomogram models were developed using these peak intensities as well as D-dimer levels to predict the occurrence of AAD. The clinical utilities of these models were assessed through receiver operating characteristics (ROC) curve analysis, net reclassification improvement (NRI), integrated discrimination improvement (IDI), and decision curve analysis (DCA) in both training and internal test cohorts.

Results

The D-dimer levels of AAD patients were significantly increased, as well as higher intensities at specific Raman peaks, including 505 cm-1, 842 cm-1, 947 cm-1, 1254 cm-1, 1448 cm-1, and 1655 cm-1 when compared to non-AAD patients. Conversely, decreased intensities were observed at Raman peaks such as 750 cm-1, 1004 cm-1, 1153 cm-1, 1208 cm-1, and 1514 cm-1 in AAD patients. Least absolute shrinkage and selection operator regression analysis on the training cohort identified eight potential predictors: D-dimer along with intensity measurements at peaks such as 505 cm-1, 750 cm-1, 1153 cm-1, 1208 cm-1, 1254 cm-1, 1448 cm-1, and 1655 cm-1. The combination of these eight potential predictors demonstrated a good discriminatory performance, with an area under the curve (AUC) value of 0.928 in the training cohort and an AUC of 0.936 in the internal test cohort, outperforming the use of D-dimer alone. Furthermore, DCA curve analysis revealed that leveraging this combination of eight potential predictors would provide substantial net benefits for clinical application. Moreover, this combination significantly augmented discrimination power, as evidenced by a continuous NRI of 39.8 % and IDI of 9.95 % in the training cohort, as well as a continuous NRI of 27.1 % and IDI of 9.95 % in the internal test cohort.

Conclusions

The employment of this combination of eight potential predictors effectively rules out AAD to a greater extent. This study presents a promising diagnostic strategy for early detection using optical diagnostic techniques such as Raman spectroscopy.

Diagnostic Accuracy of D-Dimer for Acute Aortic Syndromes: Systematic Review and Meta-Analysis

STUDY OBJECTIVE

Acute aortic syndrome is a life-threatening emergency condition. Previous systematic reviews of D-dimer diagnostic accuracy for acute aortic syndrome have been contradictory and based on limited data, but recently published studies offer potential for a more definitive overview. We aimed to perform a systematic review and meta-analysis to determine the diagnostic accuracy of D-dimer for diagnosing acute aortic syndrome.

METHODS

We searched MEDLINE, EMBASE, and the Cochrane Library from inception to February 2024. Additionally, the reference lists of included studies and other systematic reviews were thoroughly searched. All diagnostic cohort studies (prospective or retrospective) that assessed the use of D-dimer for diagnosing acute aortic syndrome compared with a reference standard test (eg, computed tomographic angiography (CTA), ECG-gated CTA, echocardiography, magnetic resonance angiography, operation, or autopsy) were included. Two independent reviewers completed study selection, data extractions and quality assessment using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Data were synthesized using a bivariate meta-analysis model.

RESULTS

Of 2017 potentially relevant citations, 25 cohort studies met the inclusion criteria, and 18 reporting the 500 ng/mL threshold were included in the primary meta-analysis. Risk of bias domains were mostly unclear due to limited study reporting. The summary sensitivity was 96.5% (95% credible interval [CrI] 94.8% to 98%) and summary specificity was 56.2% (95% CrI, 48.3% to 63.9%). Study specificity varied markedly from 33% to 86%, indicating substantial heterogeneity. Sensitivity analysis including the 7 studies reporting other thresholds showed summary sensitivity of 95.7% (95% CrI, 93.2% to 97.5%) and summary specificity of 57.5% (95% CrI, 50.1% to 64.6%).

CONCLUSION

D-dimer concentration has high sensitivity (96.5%) and moderate specificity (56.2%) for acute aortic syndrome, with some uncertainty around estimates due to risk of bias and heterogeneity. Previous meta-analysis reporting higher specificity may be explained by inclusion of case-control studies that may overestimate accuracy.

Clinical significance of elevated D-dimer in emergency department patients: a retrospective single-center analysis

INTRODUCTION

D-dimer is a marker of coagulation and fibrinolysis widely used in clinical practice for assessing thrombotic activity. While it is commonly ordered in the Emergency Department (ED) for suspected venous thromboembolism (VTE), elevated D-dimer levels can occur due to various other disorders. The aim of this study was to find out the causes of elevated D-dimer in patients presenting to a large ED in Saudi Arabia and evaluate the accuracy of D-dimer in diagnosing these conditions.

METHODS

Data was collected from an electronic hospital information system of patients who visited the ED from January 2016 to December 2022. Demographic information, comorbidities, D-dimer levels, and diagnoses were analyzed. Statistical analysis was performed using the SPSS software. The different diagnoses associated with D-dimer levels were analyzed by plotting the median D-dimer levels for each diagnosis category and their interquartile ranges (IQR). The receiver operating characteristic (ROC) curves were calculated and their area under the curve (AUC) values were demonstrated. The optimal cut-off points for specific diseases were determined based on the ROC analysis, along with their corresponding sensitivities and specificities.

RESULTS

A total of 19,258 patients with D-dimer results were included in the study. The mean age of the participants was 50 years with a standard deviation of ± 18. Of the patients, 66% were female and 21.2% were aged 65 or above. Additionally, 21% had diabetes mellitus, 20.4% were hypertensive, and 15.1% had been diagnosed with dyslipidemia. The median D-dimer levels varied across different diagnoses, with the highest level observed in aortic aneurysm 5.46 g/L. Pulmonary embolism (PE) and deep vein thrombosis (DVT) were found in 729 patients (3.8%) of our study population and their median D-dimer levels 3.07 g/L (IQR: 1.35-7.05 g/L) and 3.36 g/L (IQR: 1.06-8.38 g/L) respectively. On the other hand, 1767 patients (9.2%) were diagnosed with respiratory infections and 936 patients (4.9%) were diagnosed with shortness of breath (not specified) with median D-dimer levels of 0.76 g/L (IQR: 0.40-1.47 g/L) and 0.51 g/L (IQR: 0.29-1.06 g/L), respectively. D-dimer levels showed superior or excellent discrimination for PE (AUC = 0.844), leukemia (AUC = 0.848), and aortic aneurysm (AUC = 0.963). DVT and aortic dissection demonstrated acceptable discrimination, with AUC values of 0.795 and 0.737, respectively. D-dimer levels in respiratory infections and shortness of breath (not specified) exhibited poor to discriminatory performance.

CONCLUSION

This is the first paper to identify multiple causes of elevated D-dimer levels in Saudi Arabia population within the ED and it clearly highlights their accurate and diagnostic values. These findings draw attention to the importance of considering the specific clinical context and utilizing additional diagnostic tools when evaluating patients with elevated D-dimer levels.

Aortic Dissection Detection Risk Score and D-Dimer for Acute Aortic Syndromes in the Chinese Population: Exploration of Optimal Thresholds and Integrated Diagnostic Value

This study aimed to assess the diagnostic performance of the aortic dissection detection risk score (ADD-RS) plus D-dimer for acute aortic syndrome (AAS) in Chinese patients. Two hundred and sixty-two and 200 patients with suspected AAS symptoms were enrolled as exploration cohort and validation cohort, respectively. In exploration cohort, ADD-RS plus D-dimer (AUC = 0.929, 95%CI: 0.887-0.971) presented a better diagnostic value for AAS than ADD-RS or D-dimer alone. Meanwhile, ADD-RS > 1 and D-dimer > 2000 ng/mL were the optimal thresholds. Then, a diagnostic model integrating ADD-RS > 1 plus D-dimer > 2000 ng/mL was established, presenting sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 92.5%, 70.3%, 34.9%, and 98.2%, respectively. In validation cohort, the established diagnostic model exhibited a sensitivity, specificity, PPV, and NPV of 93.1%, 70.2%, 34.6%, and 98.4%, respectively, for diagnosing AAS. Summarily, ADD-RS > 1 and D-dimer > 2000 ng/mL are optimal thresholds for diagnosing AAS in the Chinese population. However, confirmative MSCT results are necessary.

Prediction of in-hospital death following acute type A aortic dissection

Background

Our goal was to create a prediction model for in-hospital death in Chinese patients with acute type A aortic dissection (ATAAD).

Methods

A retrospective derivation cohort was made up of 340 patients with ATAAD from Tianjin, and the retrospective validation cohort was made up of 153 patients with ATAAD from Nanjing. For variable selection, we used least absolute shrinkage and selection operator analysis, and for risk scoring, we used logistic regression coefficients. We categorized the patients into low-, middle-, and high-risk groups and looked into the correlation with in-hospital fatalities. We established a risk classifier based on independent baseline data using a multivariable logistic model. The prediction performance was determined based on the receiver operating characteristic curve (ROC). Individualized clinical decision-making was conducted by weighing the net benefit in each patient by decision curve analysis (DCA).

Results

We created a risk prediction model using risk scores weighted by five preoperatively chosen variables [AUC: 0.7039 (95% CI, 0.643–0.765)]: serum creatinine (Scr), D-dimer, white blood cell (WBC) count, coronary heart disease (CHD), and blood urea nitrogen (BUN). Following that, we categorized the cohort's patients as low-, intermediate-, and high-risk groups. The intermediate- and high-risk groups significantly increased hospital death rates compared to the low-risk group [adjusted OR: 3.973 (95% CI, 1.496–10.552), P < 0.01; 8.280 (95% CI, 3.054–22.448), P < 0.01, respectively). The risk score classifier exhibited better prediction ability than the triple-risk categories classifier [AUC: 0.7039 (95% CI, 0.6425–0.7652) vs. 0.6605 (95% CI, 0.6013–0.7197); P = 0.0022]. The DCA showed relatively good performance for the model in terms of clinical application if the threshold probability in the clinical decision was more than 10%.

Conclusion

A risk classifier is an effective strategy for predicting in-hospital death in patients with ATAAD, but it might be affected by the small number of participants.

A Retrospective Analysis of Serum D-Dimer Levels for the Exclusion of Acute Aortic Dissection

Purpose

Acute aortic dissection (AAD) is a highly fatal disorder if not promptly diagnosed. Some international studies have suggested that serum d-dimer levels may be used to exclude AAD, but data are limited. We sought to confirm that d-dimer levels are elevated in American patients with AAD. Additionally, we sought to estimate the test characteristics of the d-dimer for AAD.

Patients and Methods

We performed a retrospective analysis of patients in the Hospital Corporation of America database who arrived at the hospital between 2015 and 2019. We queried the database to find patients who had a diagnosis of AAD or (nonspecific) chest pain, and who also had a d-dimer performed within 24 hours of arrival at the hospital. The median d-dimer was compared in those diagnosed with AAD versus chest pain. We estimated the test characteristics of d-dimer for AAD at the standard cutoff value of 500 ng/mL.

Results

In total, 48,902 patients met the criteria for analysis, including 572 with AAD and 48,330 with chest pain. The median d-dimers were 2455 ng/mL and 385 ng/mL for the AAD and chest pain groups, respectively (p < 0.0001). Using a cutoff of 500 ng/mL, the sensitivity of the d-dimer was 91.1% and the specificity was 71.4%.

Conclusion

Serum d-dimer values are higher in patients with AAD than in those with nonspecific chest pain. At the standard cutoff of 500 ng/mL, the serum d-dimer has a high sensitivity for AAD, but not high enough that d-dimer levels alone can be used in isolation to exclude AAD.

[Acute Aortic Dissection: A Life-Threatening Disease Also in Neurological Emergency Medicine]

Acute aortic dissection is rare but life-threatening. The symptoms depend on the localization and reduced perfusion of the downstream organs or limbs and are therefore variable. Neurological symptoms may occur that do not immediately lead to a diagnosis and thus delay the necessary therapy. Knowing the early symptoms and warning signs of aortic dissection is therefore also crucial in neurological emergency care for quickly identifying the affected patients and for providing acute therapy. A misdiagnosis with delayed initiation of therapy can significantly worsen the patient's outcome. This study aims to establish a standardized diagnostic and therapeutic algorithm for suspected acute aortic dissection in neurological emergency care. Close interdisciplinary cooperation is mandatory.

Diagnostic and Prognostic Value of Neutrophil Extracellular Trap Levels in Patients With Acute Aortic Dissection

Background

Acute aortic dissection (AAD) is a fatal disease demanding prompt diagnosis and proper treatment. There is a lack of serum markers that can effectively assist diagnosis and predict prognosis of AAD patients.

Methods

Ninety-six AAD patients were enrolled in this study, and 249 patients with chest pain due to acute myocardial infarction, pulmonary embolism, intramural hematoma, angina or other causes and 80 healthy controls were included as control group and healthy control group. Demographics, biochemical and hematological data and risk factors were recorded as baseline characteristics. The 1-year follow-up data were collected and analyzed. The diagnostic performance and ability to predict disease severity and prognosis of NET components in serum and aortic tissue were evaluated.

Results

Circulating NET markers, citH3 (citrullination of histone 3), cell-free DNA (cfDNA) and nucleosomes, had good diagnostic value for AAD, with superior diagnostic performance to D-dimer in discriminating patients with chest pain due to other reasons in the emergency department. Circulating NET marker levels (i.e., citH3, cfDNA and nucleosomes) of AAD patients were significantly higher than that of control group and healthy control group. In addition, circulating NET markers levels were closely associated with the disease severity, in-hospital death and 1-year survival of AAD patients. Systolic blood pressure < 90 mmHg and serum citH3 levels were identified as independent risk factors for 1-year survival of AAD patients. Excessive NET components (i.e., neutrophil elastase and citH3) in the aortic tissue of AAD patient were significantly higher than that of healthy donor aortic tissue. The expression levels of granules and nuclear NET components were significantly higher in aortic tissue from AAD patients than controls.

Conclusions

Circulating NET markers, citH3, cfDNA and nucleosomes, have significant diagnostic value and predictive value of disease severity and prognosis of AAD patients. The NETs components may constitute a useful diagnostic and prognostic marker in AAD patients.

The diagnostic value of D-dimer in acute aortic dissection: a meta-analysis

Objective

This study aims to evaluate the diagnostic value of D-dimer for acute aortic dissection (AAD) by the method of meta-analysis.

Methods

PubMed, Cochrane Library, Web of Science, Embase, China National Knowledge Infrastructure (CNKI), and Wanfang databases from the establishment of the databases to December 2020 were systematically searched, and the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) system was used to evaluate the quality of the literature. STATA 15.0 software was applied to calculate the pooled sensitivity, specificity, diagnostic odds ratio (DOR), positive likelihood ratio (+LR), negative likelihood ratio (−LR) to draw summary receiver operating characteristics (SROC) curve and calculate the area under the curve (AUC). Meta-regression and subgroup analyses were used to explore the source of heterogeneity.

Results

A total of 16 clinical studies were enrolled in this study, including 1135 patients. The results of the meta-analysis showed that the pooled sensitivity was 0.96 (95% CI 0.91–0.98), the pooled specificity was 0.70 (95% CI 0.57–0.81), and the pooled DOR was 56.57 (95% CI 25.11–127.44), the pooled +LR was 3.25 (95% CI 2.18–4.85), the pooled −LR was 0.06 (95% CI 0.03–0.12), and the AUC was 0.94 (95% CI 0.91–0.95). Meta-regression and subgroup analysis results showed that publication year, sample size and cutoff value might be sources of heterogeneity. When the concentration of D-dimer was less than or equal to 500 ng/ml, the sensitivity significantly increased.

Conclusion

D-dimer has an excellent diagnostic value for AAD. It is a useful tool for detecting suspected AAD because of the excellent pooled sensitivity. D-dimer ≤ 500 ng/ml increases the potential to identify the suspected patients with AAD.

Association of biomarkers related to preoperative inflammatory and coagulation with postoperative in-hospital deaths in patients with type A acute aortic dissection

The aim of this study was to analyze the role of blood biomarkers regarding preoperative inflammation and coagulation in predicting the postoperative in-hospital mortality of patients with type A acute aortic dissection (AAD). A total of 206 patients with type A AAD who had received surgical treatment were enrolled in this study. Patients were divided into two groups: the death group (28 patients who died during hospitalization) and the survival group (178 patients). Peripheral blood samples were collected before anesthesia induction. Preoperative levels of D-dimer, fibrinogen (FIB), platelet (PLT), white blood cells (WBC) and neutrophil (NEU) were compared between the two groups. Univariable and multivariable logistic regression analysis were utilized to identify the independent risk factors for postoperative in-hospital deaths of patients with type A AAD. Receiver operating characteristic (ROC) curve were used to analyze the predictive value of these indices in the postoperative in-hospital mortality of the patients. Univariable logistic regression analysis showed that the P values of the five parameters including D-dimer, FIB, PLT, WBC and NEU were all less than 0.1, which may be risk factors for postoperative in-hospital deaths of patients with type A AAD. Further multivariable logistic regression analysis indicated that higher preoperative D-dimer and WBC levels were independent risk factors for postoperative in-hospital mortality of patients with type A AAD. ROC curve analysis indicated that application of combining FIB and PLT could improve accuracy in prediction of postoperative in-hospital mortality in patients with type A AAD. Both preoperative D-dimer and WBC in patients with type A AAD may be used as independent risk factors for the postoperative in-hospital mortality of such patients. The combination of FIB and PLT may improve the accuracy of clinical prognostic assessment.

Diagnostic performance of D-dimer in predicting venous thromboembolism and acute aortic dissection

BACKGROUND

D-dimer is elevated in a variety of conditions. The purpose of this study was to assess the positive predictive value of D-dimer to rule in patients with confirmed pulmonary embolism, deep vein thrombosis, acute aortic dissection or thrombosis of the upper extremity in comparison to patients with elevated D-dimer for other reasons.

METHODS AND RESULTS

We studied 1334 patients presenting to the emergency department with pulmonary embolism (n=193), deep vein thrombosis (n=73), acute aortic dissection (n=22), thrombosis of the upper extremity (n=8) and 1038 controls. The positive predictive value was increased with higher D-dimer concentrations improving the ability to identify diseases with high thrombus burden. Patients with venous thromboembolism, acute aortic dissection and thrombosis of the upper extremity showed a maximum positive predictive value of 85.2% at a D-dimer level of 7.8 mg/L (95% confidence interval (CI) 78.1 to 90.4). The maximum positive predictive value was lower in cancer patients with venous thromboembolism, acute aortic dissection and thrombosis of the upper extremity, reaching 68.9% at a D-dimer level of 7.5 mg/L (95% CI 57.4 to 78.4). The positive likelihood ratio was very consistent with the positive predictive value. Using a cut-off level of 0.5 mg/L, D-dimer showed a high sensitivity of at least 93%, but a very low specificity of nearly 0%. Conversely, an optimised cut-off value of 4.6 mg/L increased specificity to 95% for the detection of life-threatening venous thromboembolism, acute aortic dissection or thrombosis of the upper extremity at the costs of moderate sensitivities (58% for pulmonary embolism, 41% for deep vein thrombosis, 65% for pulmonary embolism with co-existent deep vein thrombosis, 50% for acute aortic dissection and 13% for thrombosis of the upper extremity). Using the same cut-off in cancer patients, higher values were observed for sensitivity at a specificity level of more than 95%. The area under the curve for the discrimination of venous thromboembolism/acute aortic dissection/thrombosis of the upper extremity from controls was significantly higher in cancer versus non-cancer patients (area under the curve 0.905 in cancer patients, 95% CI 0.89 to 0.92, vs. area under the curve 0.857 in non-cancer patients, 95% CI 0.84 to 0.88; P=0.0349).

CONCLUSION

D-dimers are useful not only to rule out but also to rule in venous thromboembolism and acute aortic dissection with an at least moderate discriminatory ability, both in patients with and without cancer.

An early aortic dissection screening model and applied research based on ensemble learning

Background

As a particularly dangerous and rare cardiovascular disease, aortic dissection (AD) is characterized by complex and diverse symptoms and signs. In the early stage, the rate of misdiagnosis and missed diagnosis is relatively high. This study aimed to use machine learning technology to establish a fast and accurate screening model that requires only patients' routine examination data as input to obtain predictive results.

Methods

A retrospective analysis of the examination data and diagnosis results of 53,213 patients with cardiovascular disease was conducted. Among these samples, 802 samples had AD. Forty-two features were extracted from the patients' routine examination data to establish a prediction model. There were five ensemble learning models applied to explore the possibility of using machine learning methods to build screening models for AD, including AdaBoost, XGBoost, SmoteBagging, EasyEnsemble and XGBF. Among these, XGBF is an ensemble learning model that we propose to deal with the imbalance of the positive and negative samples. The seven-fold cross validation method was used to analyze and verify the performance of each model. Due to the imbalance of the samples, the evaluation indicators were sensitivity and specificity.

Results

Comparative experiments showed that the sensitivity of XGBF was 80.5%, which was better than the 16.1% of AdaBoost, 15.7% of XGBoost, 78.0% of SmoteBagging and 77.8% of EasyEnsemble. Additionally, XGBF had relatively high specificity, and the training time consumption was short. Based on these three indicators, XGBF performed best, and met the application requirements, which means through careful design, we can use machine learning technology to achieve early AD screening.

Conclusions

Through reasonable design, the ensemble learning method can be used to build an effective screening model. The XGBF has high practical application value for screening for AD.

The Value of d-Dimer Level in Predicting Contrast-Induced Acute Kidney Injury in Patients With Acute ST-Segment Elevation Myocardial Infarction After PCI

Contrast-induced acute kidney injury (CI-AKI) is a serious complication of percutaneous coronary intervention (PCI) in patients with acute ST-segment elevation myocardial infarction (STEMI). Early identification of high-risk patients has an essential role in preventing CI-AKI. This study was designed to evaluate the predictive value of d-dimer, a marker of thrombosis and hypercoagulable state, for CI-AKI and prognosis in patients with STEMI. We included 400 patients with STEMI who underwent PCI. The patients were subdivided into 4 groups according to d-dimer level using the 4-quantile method. Contrast-induced acute kidney injury occurred in 66 (16.5%) patients. The incidence of CI-AKI in the highest quartile of the d-dimer groups (29.0%) was higher than that in the other 3 groups. Multivariable logistic regression showed that a low d-dimer level was significantly associated with a decreased risk of CI-AKI independent of confounding factors, with an odds ratio (OR) of 0.487 (95% CI: 0.178-0.931, P = 0.041) for those in the first quartile compared with those in the highest quartile. Age (OR: 1.047, 95% CI: 1.003-1.092), diabetes mellitus (OR: 5.896, 95% CI: 2.496-13.927), anemia (OR: 3.488, 95% CI: 1.308-9.306), and total bilirubin (OR: 0.946, 95% CI: 0.904-0.992) were independent predictors of CI-AKI. The incidence of major adverse cardiovascular and cerebral events and all-cause mortality within 30 days, 6 months, and 1 year after PCI in the highest quartile of the d-dimer groups were higher than those in the other 3 groups. In conclusion, increasing d-dimer levels were independently associated with the incidence of CI-AKI and adverse outcomes in patients with STEMI after PCI.

Timely identification of atypical acute aortic dissection in the emergency department:a study from a tertiary hospital

Background/aim

Acute aortic dissection (AAD) is a rare but fatal disease if left untreated. Symptoms are often similar to common conditions; therefore, the diagnostic strategy is important. We aimed to identify the atypical symptoms in a timely manner without putting patients at greater risk for undetected AAD.

Materials and methods

We conducted a retrospective observational study of 59 AAD patients with both atypical and typical symptoms from January 2012 to December 2016. Patients with atypical symptoms continuing more than 30 min underwent a D-dimer test and computed tomography (CT) or computed tomographic angiography (CTA).

Results

Of the 59 AAD patients, 22 were atypical. In the atypical group, the median delay time in our hospital was 3.1 h; average delay time after July 2015 was shorter than average delay time before June 2015 (16.59 ± 24.70 vs. 1.90 ± 0.57 h, P = 0.076).

Conclusions

For patients in the emergency department who are suspected of having AAD, incorporating atypical symptoms with high levels of D-dimer into a triage strategy could improve the efficiency of clinical decision making. Furthermore, essential education directed towards the recognition of the atypical symptoms of AAD for front-line physicians may aid in a timely diagnosis, as compared with the usual assessments in the emergency department.

Characteristics and Treatment Outcomes of Acute Type A Aortic Dissection With Elevated D-Dimer Concentration

Background

Clinical characteristics and treatment outcomes of acute type A aortic dissection with D‐dimer elevation have not been clarified.

Methods and Results

D‐dimer was measured preoperatively within 24 hours of symptom onset in 262 patients with acute type A aortic dissection. The median (and interquartile range) admission D‐dimer concentration in our total patient group was 26.7 (8.3–85.9) μg/mL. Median (interquartile range) D‐dimer concentrations were 5.0 (2.6–18.0) μg/mL for complete false lumen thrombosis (n=33), 60.9 (19.4–160.4) μg/mL for partial thrombosis (n=81), 26.5 (10.0–70.6) μg/mL for a patent false lumen (n=131), and 8.7 (3.2–26.9) μg/mL for ulcerlike projection (n=17) (P<0.01). With a D‐dimer concentration of ≤8.3 μg/mL representing the lower quartile, we then investigated predictors of a low D‐dimer level. Multivariate analysis showed dissection limited to the ascending aorta (P<0.01; odds ratio, 9.81) or descending aorta (P<0.01; odds ratio, 7.68), a completely thrombosed false lumen (P<0.01; odds ratio, 4.02), and absence of brain ischemia (P=0.013; odds ratio, 4.74) to be predictors of the lower D‐dimer concentration. Compared with patients with a low D‐dimer concentration (≤8.3 μg/mL, n=66), patients with a D‐dimer concentration >8.3 μg/mL (n=196) had a reduced preoperative platelet count and increased operation time and transfusion volume. In‐hospital mortality was elevated in this group (1.5% versus 11.2%; P=0.031), although 7‐year survival did not differ for hospital survivors (lower versus higher, 93.1% versus 79.1%; P=0.21).

Conclusions

D‐dimer concentrations are strongly influenced by the extent of dissection and false lumen status. Operative risks are increased in patients with a relatively high D‐dimer concentration.

Clinical Examination for Acute Aortic Dissection: A Systematic Review and Meta-analysis

OBJECTIVES

Acute aortic dissection is a life-threatening condition due to a tear in the aortic wall. It is difficult to diagnose and if missed carries a significant mortality.

METHODS

We conducted a librarian-assisted systematic review of PubMed, MEDLINE, Embase, and the Cochrane database from 1968 to July 2016. Titles and abstracts were reviewed and data were extracted by two independent reviewers (agreement measured by kappa). Studies were combined if low clinical and statistical heterogeneity (I²  < 30%). Study quality was assessed using the QUADAS-2 tool. Bivariate random effects meta analyses using Revman 5 and SAS 9.3 were performed.

RESULTS

We identified 792 records: 60 were selected for full text review, nine studies with 2,400 participants were included (QUADAS-2 low risk of bias, κ = 0.89 [for full-text review]). Prevalence of aortic dissection ranged from 21.9% to 76.1% (mean ± SD = 39.1% ± 17.1%). The clinical findings increasing probability of aortic dissection were 1) neurologic deficit (n = 3, specificity = 95%, positive likelihood ratio [LR+] = 4.4, 95% confidence interval [CI] = 3.3-5.7, I²  = 0%) and 2) hypotension (n = 4, specificity = 95%, LR+ = 2.9 95% CI = 1.8-4.6, I²  = 42%), and decreasing probability were the absence of a widened mediastinum (n = 4, sensitivity = 76%-95%, negative likelihood ratio [LR-] = 0.14-0.60, I²  = 93%) and an American Heart Association aortic dissection detection (AHA ADD) risk score < 1 (n = 1, sensitivity = 91%, LR- = 0.22, 95% CI = 0.15-0.33).

CONCLUSIONS

Suspicion for acute aortic dissection should be raised with hypotension, pulse, or neurologic deficit. Conversely, a low AHA ADD score decreases suspicion. Clinical gestalt informed by high- and low-risk features together with an absence of an alternative diagnosis should drive investigation for acute aortic dissection.

Usefulness of Measuring the Serum Elastin Fragment Level in the Diagnosis of an Acute Aortic Dissection

Previous reports have shown that serum elastin fragments (SEFs) may be a useful biomarker for the diagnosis of an acute aortic dissection (AAD). However, because the reference interval of SEFs has not been established, it has not been determined whether SEFs are really useful for the diagnosis of AAD. The purpose of this study was to determine the usefulness of measuring SEFs for the diagnosis of AAD. A total of 42 consecutive patients aged 68 ± 18 years who were diagnosed with an AAD were studied. Patient background and SEF levels were examined on admission. SEF levels were also measured in patients undergoing a medical examination (n = 531, age 54 ± 17 years) to compare with those with an AAD. In the control group, SEF levels increased with age (R = 0.725, p <0.001). Then, we defined the upper limit of the reference interval of SEF levels as the 97.5th percentile of control SEF grouped by decade of life from the sixth to ninth decade. The overall risk of AAD exceeding the upper limit of the reference interval at each decade was 10% (4 of 42). For patients in their 60s and 70s, median SEF levels in the AAD group (89 [77 to 104], 93 [60 to 123] ng/ml, respectively) were not significantly higher than those in the control group (79 [68 to 92], 90 [79 to 106] ng/ml, respectively; p = 0.081 and 0.990, respectively). Our data suggest that measuring SEF levels may not be useful in the diagnosis of an AAD as the upper limit of the reference interval of the SEF level was unexpectedly higher.

How to use D-dimer in acute cardiovascular care

D-dimer testing is important to aid in the exclusion of venous thromboembolic events (VTEs), including deep venous thrombosis and pulmonary embolism, and it may be used to evaluate suspected aortic dissection. D-dimer is produced upon activation of the coagulation system with the generation and subsequent degradation of cross-linked fibrin by plasmin. Many different assays for D-dimer testing are currently used in routine care. However, these tests are neither standardized nor harmonized. Consequently, only clinically validated assays and assay specific decision limits should be used for routine testing. For the exclusion of pulmonary embolism/deep vein thrombosis, age-adjusted cut-offs are recommend. Clinicians must be aware of the validated use of their hospital's D-dimer assay to avoid inappropriate use of this biomarker in routine care.

Diagnostic test accuracy of D-dimer for acute aortic syndrome: systematic review and meta-analysis of 22 studies with 5000 subjects

Diagnostic test accuracy of D-dimer for acute aortic dissection (AAD) has not been evaluated by meta-analysis with the bivariate model methodology. Four databases were electrically searched. We included both case-control and cohort studies that could provide sufficient data concerning both sensitivity and specificity of D-dimer for AAD. Non-English language articles and conference abstract were allowed. Intramural hematoma and penetrating aortic ulcer were regarded as AAD. Based on 22 eligible articles consisting of 1140 AAD subjects and 3860 non-AAD subjects, the diagnostic odds ratio was 28.5 (95% CI 17.6-46.3, I(2) = 17.4%) and the area under curve was 0.946 (95% CI 0.903-0.994). Based on 833 AAD subjects and 1994 non-AAD subjects constituting 12 studies that used the cutoff value of 500 ng/ml, the sensitivity was 0.952 (95% CI 0.901-0.978), the specificity was 0.604 (95% CI 0.485-0.712), positive likelihood ratio was 2.4 (95% CI 1.8-3.3), and negative likelihood ratio was 0.079 (95% CI 0.036-0.172). Sensitivity analysis using data of three high-quality studies almost replicated these results. In conclusion, D-dimer has very good overall accuracy. D-dimer <500 ng/ml largely decreases the possibility of AAD. D-dimer >500 ng/ml moderately increases the possibility of AAD.

Predictive Value of D-Dimer Levels and Tissue Doppler Mitral Annular Systolic Velocity for Detection of Left Atrial Appendage Thrombus in Patients with Mitral Stenosis in Sinus Rhythm

BACKGROUND

Transesophageal echocardiogram (TEE) is a gold standard test for diagnosis of left atrial (LA) thrombus, but it has limited sensitivity for identification of small thrombi within side lobes. Thus, the absence of visualizing a left atrial appendage (LAA) thrombus does not equate with the absence of a LAA thrombus.

AIM

To assess the predictive value of mitral annular systolic velocity (Sa) and D-dimer for the detection of LA thrombus and spontaneous echocardiographic contrast (SEC) in mitral stenosis (MS) patients with sinus rhythm (SR).

METHODS

Transthoracic echocardiogram, TEE, and D-dimer analysis were performed in 104 severe MS patients and divided them into three groups: Group I:no LA thrombus or SEC; Group II:LA SEC only; and Group III:LA thrombus.

RESULTS

Group III had more severe New York Heart Association (NYHA) class (III-IV) dyspnea and lower Sa (6.9 ± 0.7 vs.10.0 ± 1.2 cm/sec), lower LAA late emptying velocity (17.7 ± 2.1 vs. 24.4 ± 4.2 cm/sec), larger LA transverse dimension, and LAA area (LAAA) than group I+II. Mean D-dimer levels were higher in groups III and II than in group I. In multivariate analysis Sa, D-dimer levels, LAAA, and NYHA class were independent predictors of LA thrombus. ROC curve analysis revealed that higher Sa >8 cm/sec and lower D-dimer levels <370 μg/L predict the absence of LA thrombus and lower Sa <8 cm/sec and higher D-dimer levels >510 μg/L predict the presence of LA thrombus.

CONCLUSION

Measurement of Sa and D-dimer levels is necessary for better assessment of LA thrombus and SEC, for identification of patients who are at high risk for LA thrombus formation and for initiation of prophylactic anticoagulation.

Aortic dissection associated with blunt chest trauma diagnosed by elevated D-dimer

INTRODUCTION

Similar to spontaneous aortic dissection, traumatic aortic dissection is diagnosed with a careful history and physical exam, chest radiograph, and ultimately, dedicated aortic imaging. The diagnosis of spontaneous aortic dissection may be aided by using the serum D-dimer test. The use of D-dimer for diagnosing aortic injury in the setting of blunt trauma has not previously been reported.

PRESENTATION OF CASE

We present a case of aortic dissection in a 61-year-old male diagnosed when the patient presented with chest pain after blunt chest trauma.

DISCUSSION

The patient had no known history or risk factors for aortic disease. None of the classic findings were present by history, physical examination or chest radiograph and the diagnosis was made as the result of an elevated D-dimer. We discuss how the D-dimer test fortuitously led to the diagnosis in this case, and the implications.

CONCLUSION

D-dimer could be helpful in diagnosing aortic injuries in low-risk chest trauma patients.

Aortic Dissection and Sudden Unexpected Deaths: A Retrospective Study of 31 Forensic Autopsy Cases

Acute aortic dissection (AAD) is the most common cause of sudden unexpected death related to aortic diseases. A retrospective study of 31 sudden unexpected deaths caused by AAD was conducted at Xi'an Jiaotong University Forensic Center from 2001 to 2012. We summarized the forensic characteristics of AAD and assessed the clinically diagnostic accuracy of AAD. The characteristics of sudden unexpected death due to AAD were male predominant (male: female=6.7:1), relatively young with the mean age of 44, and predominance of type A dissection (77.4%). Cardiac tamponade was the most frequent cause of sudden death (87.1%). Of the 31 cases, 26 (83.9%) patients were not recognized clinically and were misdiagnosed with acute myocardial infarction, coronary artery disease, cholecystitis, acute gastroenteritis, renal/urinary lithiasis, or acute pancreatitis. In summary, AAD can be difficult to recognize, diagnosis is therefore sometimes delayed or missed. The medicolegal death investigation can help physicians have a better understanding of AAD.

Consideration of two cases of ascending aortic dissection that began with stroke-like symptoms

We recently experienced two patients with stroke-like symptoms and ascending aortic dissection (AAD) in our outpatient department. Both patients were transferred to our hospital presenting with neurological deficit such as hemiparesis and conjugate deviation. They did not complain from any chest or abdominal pain. Their MRI did not show fresh infarction or main branch occlusion. A chest CT image showed AAD. The former patient was immediately transferred to a tertiary hospital and the latter received conservative management in the cardiovascular department. Discussion. As neither patient was experiencing any pain, we initially diagnosed them with ischemic stroke and began treatment. Fortunately, bleeding complications did not occur. In such cases, problems are caused when intravenous tissue plasminogen activator (t-PA) injection is administered with the aim of reopening the occluded intracranial arteries. In fact, patients with AAD undergoing t-PA injection have been reported to die from bleeding complications without any recognition of the dissection. These findings suggest that confirmation using carotid ultrasound, carotid MR angiography, and a D-dimer test is crucial and should be adopted in emergency departments.

D-dimer as a biomarker for acute aortic dissection: a systematic review and meta-analysis

To perform a meta-analysis and examine the use of D-dimer levels for diagnosing acute aortic dissection (AAD). Medline, Cochrane, EMBASE, and Google Scholar were searched until April 23, 2014, using the following search terms: biomarker, acute aortic dissection, diagnosis, and D-dimer. Inclusion criteria were diagnosis of acute aortic dissection, D-dimer levels obtained, 2-armed study. Outcome measures were the accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of D-dimer level for the diagnosis of AAD. Sensitivity analysis was performed using the leave-one-out approach. Of 34 articles identified, 5 met the inclusion criteria and were included in the analysis. The age of participants was similar between treatments within studies. The number of AAD patients ranged from 16 to 107 (total = 274), and the number of control group patients ranged from 32 to 206 (total = 469). The pooled sensitivity of D-dimer levels in AAD patients was 94.5% (95% confidence interval [CI] 78.1%-98.8%, P < 0.001), and the specificity was 69.1% (95% CI 43.7%-86.5%, P = 0.136). The pooled area under the receiver-operating characteristic curve for D-dimer levels in AAD patients was 0.916 (95% CI 0.863-0.970, P < 0.001). The direction and magnitude of the combined estimates did not change markedly with the exclusion of individual studies, indicating the meta-analysis had good reliability. D-dimer levels are best used for ruling out AAD in patients with low likelihood of the disease.

Year in review 2013: Critical Care--out-of-hospital cardiac arrest, traumatic injury, and other emergency care conditions

In this review, we discuss articles published in 2013 contributing to the existing literature on the management of out-of-hospital cardiac arrest and the evaluation and management of several other emergency conditions, including traumatic injury. The utility of intravenous medications, including epinephrine and amiodarone, in the management of cardiac arrest is questioned, as are cardiac arrest termination-of-resuscitation rules. Articles discussing mode of transportation in trauma are evaluated, and novel strategies for outcome prediction in traumatic injury are proposed. Diagnostic strategies, including computerized tomography scan for the diagnosis of smoke inhalation injury and serum biomarkers for the diagnosis of post-cardiac arrest syndrome and acute aortic dissection, are also explored. Although many of the articles discussed raise more questions than they answer, they nevertheless provide ample opportunity for further investigation.

The role of D-dimers in the diagnosis of acute aortic dissection

Acute aortic dissection (AAD) is a life threatening cardiovascular medical emergency with a poor prognosis. To explore the utility of D-dimers (DD) in the diagnosis of AAD, we performed a prospective study and conducted a meta-analysis of previous studies. 368 suspected patients were enrolled, including AAD n = 89, PE n = 12, AMI n = 167, normal controls n = 100. All patients had a DD test immediately after admission. We then performed a comprehensive computer search to identify studies investigating using DD as a screening tool for AAD. Finally, we pooled these data to estimate sensitivity, specificity, positive and negative likelihood ratios (LRs) by using DerSimonian-Laird random-effects models. The DD concentrations in the AAD group were significantly higher than those in the AMI and normal control groups. However, the DD level of 500 ng/ml had a poor sensitivity of 51.7 % and specificity of 89.2 % in the diagnosis of AAD. Subgroup analyses found that DD only showed a well discriminative ability of distinguishing AAD patients from normal controls (specificity and positive LR was 97 % and 17.2, respectively). The pooled sensitivity, specificity, positive and negative LR in our meta-analysis was 89, 68 %, 2.71, 0.07, respectively. In conclusion, our results suggest that plasma DD levels cannot add to the certainty of AAD diagnosis and it is not a good biomarker for AAD. In the future, prospective research on patients from many parts of the world is warranted to validate our findings. In addition, different controls, methods of plasma DD assays and other factors should be considered.

Early recognition of acute thoracic aortic dissection and aneurysm

BACKGROUND

Thoracic aortic dissection (TAD) and aneurysm (TAA) are rare but catastrophic. Prompt recognition of TAD/TAA and differentiation from acute coronary syndrome (ACS) is difficult yet crucial. Earlier identification of TAA/TAD based upon routine emergency department screening is necessary.

METHODS

A retrospective analysis of patients that presented with acute thoracic complaints to the ED from January 2007 through June 2012 was performed. Cases of TAA/TAD were compared to an equal number of controls which consisted of patients with the diagnosis of ACS. Demographics, physical findings, EKG, and the results of laboratory and radiological imaging were compared. P-value of > 0.05 was considered statistically significant.

RESULTS

In total, 136 patients were identified with TAA/TAD, 0.36% of patients that presented with chest complaints. Compared to ACS patients, TAA/TAD group was older (68.9 vs. 63.2 years), less likely to be diabetic (13% vs 32%), less likely to complain of chest pain (47% vs 85%) and head and neck pain (4% vs 17%). The pain for the TAA/TAD group was less likely characterized as tight/heavy in nature (5% vs 37%). TAA/TAD patients were also less likely to experience shortness of breath (42% vs. 51%), palpitations (2% vs 9%) and dizziness (2% vs 13%) and had a greater incidence of focal lower extremity neurological deficits (6% vs 1%), bradycardia (15% vs. 5%) and tachypnea (53% vs. 22%). On multivariate analysis, increasing heart rate, chest pain, diabetes, head & neck pain, dizziness, and history of myocardial infarction were independent predictors of ACS.

CONCLUSIONS

Increasing heart rate, chest pain, diabetes, head & neck pain, dizziness, and history of myocardial infarction can be used to differentiate acute coronary syndromes from thoracic aortic dissections/aneurysms.

Preliminary development of a clinical decision rule for acute aortic syndromes

OBJECTIVE

Patients with suspected acute aortic syndromes (AAS) often undergo computed tomography (CT) with negative results. We sought clinical and diagnostic criteria to identify low-risk patients, an initial step in developing a clinical decision rule.

METHODS

We retrospectively identified all adults presenting to our emergency department (ED) from January 1, 2006, to August 1, 2010, who underwent CT angiography for suspected AAS without prior trauma or AAS. A total of 1465 patients met inclusion criteria; a retrospective case-controlled review (ratio 1:4) was conducted. Cases were diagnosed with aortic dissection, intramural hematoma, penetrating atherosclerotic ulcer, or ruptured aneurysm.

RESULTS

Of the patients who underwent CT, 2.7% (40/1465) had an AAS; 2 additional cases were diagnosed after admission (ED miss rate, 5% [2/42]). Patients with AAS were significantly older than controls (66 vs 59 years; P = .008). Risk factors included abnormal chest radiograph (sensitivity, 79% [26/33]; specificity, 82% [113/137]) and acute chest pain (sensitivity, 83% [29/35]; specificity, 71% [111/157]). None of the 19 patients with resolved pain upon ED presentation had AAS. These data support a 2-step rule: first screen for ongoing pain; if present, screen for acute chest pain or an abnormal chest radiograph. This approach achieves a 54% (84/155) reduction in CT usage with a sensitivity for AAS of 96% (95% confidence interval, 89%-100%), negative predictive value of 99.8% (99.4%-100%), and a false-negative rate of 1.7% (1/84).

CONCLUSIONS

Our results demonstrate a need to safely identify patients at low risk for AAS who can forgo CT. We developed a preliminary 2-step clinical decision rule, which requires validation.

Rule out of acute aortic dissection with plasma matrix metalloproteinase 8 in the emergency department

Introduction

Matrix metalloproteinases (MMPs) are involved in aortic pathophysiology. Preliminary studies have detected increased plasma levels of MMP8 and MMP9 in patients with acute aortic dissection (AAD). However, the performance of plasma MMP8 and MMP9 for the diagnosis of AAD in the emergency department is at present unknown.

Methods

The levels of MMP8 and MMP9 were measured by ELISA on plasma samples obtained from 126 consecutive patients evaluated in the emergency department for suspected AAD. All patients were subjected to urgent computed tomography (CT) scan for final diagnosis.

Results

In the study cohort (N = 126), AAD was diagnosed in 52 patients and ruled out in 74 patients. Median plasma MMP8 levels were 36.4 (interquartile range 24.8 to 69.3) ng/ml in patients with AAD and 13.2 (8.1 to 31.8) ng/ml in patients receiving an alternative final diagnosis (P <0.0001). Median plasma MMP9 levels were 169.2 (93.0 to 261.8) ng/ml in patients with AAD and 80.5 (41.8 to 140.6) ng/ml in patients receiving an alternative final diagnosis (P = 0.001). The area under the curve (AUC) on receiver-operating characteristic (ROC) analysis of MMP8 and MMP9 for the diagnosis of AAD was respectively 0.75 and 0.70, as compared to 0.87 of D-dimer. At the cutoff of 3.6 ng/ml, plasma MMP8 had a sensitivity of 100.0% (95% CI, 93.2% to 100.0%) and a specificity of 9.5% (95% CI, 3.9% to 18.5%) and ruled out AAD in 5.6% of patients. Combination of plasma MMP8 with D-dimer increased the AUC on ROC analysis to 0.89. Presence of MMP8 <11.0 ng/ml and D-dimer <1.0 or <2.0 µg/ml provided a negative predictive value of 100% and ruled out AAD in 13.6% and 21.4% of patients respectively.

Conclusions

Low levels of plasma MMP8 can rule out AAD in a minority of patients. Combination of plasma MMP8 and D-dimer at individually suboptimal cutoffs could safely rule out AAD in a substantial proportion of patients evaluated in the emergency department.

Elevated plasma D-dimer and hypersensitive C-reactive protein levels may indicate aortic disorders

OBJECTIVE

D-dimer and C-reactive protein are of diagnostic and predictive values in patients have thrombotic tendency, such as vascular thrombosis, coronary artery disease and aortic dissection. However, the comparative study in these biomarkers between the patients with acute aortic dissection and coronary artery disease has not been sufficiently elucidated.

METHODS

Consecutive surgical patients for acute type A aortic dissection (20 patients), aortic aneurysm (nine patients) or coronary artery disease (20 patients) were selected into this study. Plasma from preoperative blood samples and supernatant of aortic homogenate of the surgical specimens were detected for D-dimer and hypersensitive C-reactive protein (hs-CRP).

RESULTS

Plasma D-dimer and hs-CRP values in type A aortic dissection or aortic aneurysm were much higher than in coronary artery disease patients or the healthy control (for D-dimer, aortic dissection: coronary artery disease, 0.4344 ± 0.2958 µg/ml vs. 0.0512 ± 0.0845 µg/ml, P < 0.0001; aortic dissection: healthy control, 0.4344 ± 0.2958 µg/ml vs. 0.1250 ± 0.1295 µg/ml, P = 0.0005; aortic aneurysm: coronary artery disease, 0.4200 ± 0.4039 µg/ml vs. 0.0512 ± 0.0845 µg/ml, P = 0.0013; and aortic aneurysm: healthy control, 0.4200 ± 0.4039 µg/ml vs. 0.1250 ± 0.1295 µg/ml, P = 0.0068; and for hs-CRP, aortic dissection: coronary artery disease, 4.400± 3.004 mg/L vs. 1.232±0.601 mg/L, P < 0.0001; aortic dissection:healthy control, 4.400 ± 3.004 mg/L vs. 0.790 ± 0.423 mg/L, P < 0.0001; aortic aneurysm: coronary artery disease, 2.314 ± 1.399 mg/L vs. 1.232 ± 0.601 mg/L, P = 0.0084; aortic aneurysm: healthy control, 2.314 ± 1.399 mg/L vs. 0.790 ± 0.423 mg/L, P = 0.0002; and coronary artery disease: healthy control, 1.232 ± 0.601 mg/L vs. 0.790 ± 0.423 mg/L, P = 0.0113). Besides, there were close correlations between plasma D-dimer and hs-CRP in overall (Y = 4.8798X + 0.8138, r² = 0.4497, r = 0.671, P < 0.001), aortic dissection (Y = 2.6298X + 1.2098, r² = 0.5762, r = 0.759, P < 0.001), and aortic aneurysm (Y = 7.1341X + 1.3006, r² = 0.4935, r = 0.7025, P = 0.048) groups rather than in the coronary artery disease or healthy control subjects. In addition, there were no significant differences between D-dimer and hs-CRP values of the aortic supernatant among groups except for undetectable D-dimer in the aortic supernatant of the coronary artery disease group.

CONCLUSIONS

The patients with acute aortic dissection and aortic aneurysm may reflect the extensive inflammatory reaction and severe coagulopathies in the patients with acute type A aortic dissection, and thoracic aortic aneurysm in comparison to the coronary patients and healthy control individuals. The detections after onset in the patients with acute chest pain may help making a differential diagnosis between the aortopathies and ischemic heart disease. The scanty significance of the tissue biomarkers may preclude their diagnostic value in clinical practice.

Meta-analysis of usefulness of d-dimer to diagnose acute aortic dissection

Numerous studies have examined whether plasma D-dimer (DD) can be used to identify patients with acute aortic dissection (AAD). These studies have been inconclusive because of their limited sample sizes and the different cut-off values employed. We aimed to conduct a systematic review and meta-analysis to examine the utility of plasma DD as a screening tool for AAD. We systematically searched EMBASE and MEDLINE and hand-searched relevant articles to identify studies investigating plasma DD as a screening tool for AAD. A value of 500 ng/ml was defined as the threshold for a positive plasma DD finding because it is widely used for ruling out pulmonary emboli. Using DerSimonian-Laird random-effects models we pooled data across studies to estimate sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios (LRs). We identified 7 studies involving 298 subjects with AAD and 436 without. When data were pooled across studies, sensitivity (0.97, 95% confidence interval [CI] 0.94 to 0.99) and negative predictive value (0.96, 95% CI 0.93 to 0.98) were high. Specificity (0.56, 95% CI 0.51 to 0.60) and positive predictive value (0.60, 95% CI 0.55 to 0.66) were low. Negative LR showed an excellent discriminative ability (0.06, 95% CI 0.03 to 0.12), whereas positive LR did not (2.43, 95% CI 1.89 to 3.12). In conclusion, our meta-analysis suggests that plasma DD <500 ng/ml is a useful screening tool to identify patients who do not have AAD. Plasma DD may thus be used to identify subjects who are unlikely to benefit from further aortic imaging.