Simple and Useful Tests for Discriminating Between Acute Aortic Dissection of the Ascending Aorta and Acute Myocardial Infarction in the Emergency Setting

Diagnostic accuracy of alternative biomarkers for acute aortic syndrome: a systematic review

BACKGROUND

D-dimer is the only biomarker currently recommended in guidelines for the diagnosis of acute aortic syndrome (AAS). We undertook a systematic review to determine whether any alternative biomarkers could be useful in AAS diagnosis.

METHODS

We searched electronic databases (including MEDLINE, EMBASE and the Cochrane Library) from inception to February 2024. Diagnostic studies were eligible if they examined biomarkers other than D-dimer for diagnosing AAS compared with a reference standard test in people presenting to the ED with symptoms of AAS. Case-control studies were identified but excluded due to high risk of bias. Selection of studies, data extraction and risk of bias assessments using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool were undertaken independently by at least two reviewers. We used narrative synthesis to summarise the findings.

RESULTS

We identified 2017 citations, included 13 cohort studies (n=76-999), and excluded 38 case-control studies. Methodological quality was variable, with most included studies having unclear or high risk of bias and applicability concerns in at least one item of the QUADAS-2 tool. Only two studies reported biomarkers with sensitivity and specificity comparable to D-dimer (ie, >90% and >50%, respectively). Wang et al reported 99.1% sensitivity and 84.9% specificity for soluble ST2; however, these findings conflicted with estimates of 58% sensitivity and 70.8% specificity reported in another study. Chun and Siu reported 95.6% sensitivity and 56.1% specificity for neutrophil count, but this has not been confirmed elsewhere.

CONCLUSION

There are many potential alternative biomarkers for AAS but few have been evaluated in more than one study, study designs are often weak and reported biomarker accuracy is modest or inconsistent between studies. Alternative biomarkers to D-dimer are not ready for routine clinical use.

PROSPERO REGISTRATION NUMBER

CRD42022252121.

Circulating biomarkers in acute aortic dissection versus acute myocardial infarction: a systematic review

INTRODUCTION

This systematic review aimed to discuss the current knowledge of possibly useful circulatory biomarkers (other than D-dimers) in the diagnosis of patients with an acute aortic dissection (AAD), to distinguish these patients from patients with Acute Myocardial Infarction (AMI).

EVIDENCE ACQUISITION

This study followed the PRISMA guidelines. The databases PubMed, EMBASE and Scopus were systematically searched from inception to May 2023. Studies were included if they presented measurements of biomarker(s) in the blood/plasma/serum samples from adult patients with AAD versus AMI. Articles were excluded if aortic dissection was subacute or chronic (>14 days), if they lack a control group (AMI), or if they were animal studies, revisions, or editorials. The main outcome was the identification of biomarkers that exhibited diagnostic potential to differentiate patients with AAD versus AMI.

EVIDENCE SYNTHESIS

The research query resulted in 1342 articles after the removal of duplicates, from which seven were included in the systematic review. The biomarkers identified included general blood assessment, metabolomics, products of the degradation of fibrin, extracellular matrix markers and an ischemia-associated molecule. Most studies lack diagnostic validity such as sensitivity and specificity. In six studies, the concentration of a total of six biomarkers showed significative differences between AAD and AMI group.

CONCLUSIONS

A great heterogeneity of molecules has been studied as putative diagnostic markers of AAD versus AMI. Studies of better quality are needed, presenting the diagnostic validity of the molecules under analysis and the putative synergic diagnostic value of the molecules identified so far.

D-dimer as a Rule-Out for Aortic Dissection

Introduction Acute aortic dissection (AAD) represents a significant diagnostic challenge with a high mortality rate if not treated promptly. This challenge arises from the diverse clinical presentations of AAD, and its symptom overlap with other medical conditions. Although both helical CT and transesophageal echocardiography are reliable diagnostic tools for AAD, they are not feasible for every suspected case. Furthermore, limited research on D-dimer's utility in ruling out AAD has been conducted due to the condition's rarity. Methods This study utilizes the TriNetX database (https://trinetx.com/), encompassing data from 54 healthcare organizations across the United States over the past two decades from 85 million patients. The objective is to evaluate the sensitivity of an elevated D-dimer level in diagnosing AAD across a much larger patient cohort than previously studied. Results Retrospectively analyzing this dataset, there were 1,319 patients identified with a confirmed AAD who had undergone D-dimer testing within a day of diagnosis. Of these, 1,252 patients exhibited D-dimer levels exceeding 400 ng/ml while 1,227 had levels surpassing 500 ng/ml. Notably, a D-dimer cutoff of 400 ng/ml demonstrated a sensitivity of 0.949 while a 500 ng/ml cutoff yielded a sensitivity of 0.930. Conclusion This large retrospective cohort study demonstrates that a blood D-dimer level is highly sensitive in assaying for AAD. The D-dimer levels analyzed showed a remarkable sensitivity in ruling out AAD, avoiding the need for more invasive testing in low-risk patients.

Diagnostic biomarkers and aortic dissection: a systematic review and meta-analysis

BACKGROUND

Aortic dissection (AD) is a serious and fatal vascular disease. The earlier the condition of AD patients can be assessed precisely, the more scientifically controlled the patient's condition will be. Therefore, timely and accurate diagnosis is significant for AD. Blood biomarker testing as a method of liquid biopsy can improve the diagnostic efficiency of AD. This study conducted a systematic review of the current blood diagnostic biomarkers of AD.

METHODS

The PubMed, Cochrane Library, Web of Science, and Embase electronic databases were systematically searched from inception to January 1, 2023, using the terms "aortic dissection", "serum", "plasma" and "diagnosis". Stata 12.0 software was used to perform Random effects meta-analysis was performed using Stata 12.0 software to determine the effect sizes and corresponding 95% confidence intervals. Then, a summary receiver operator characteristic (SROC) curve was drawn, and the area under the ROC curve (AUC) was calculated.

RESULTS

D-dimer had the best sensitivity and AUC for AD, with values of 0.96 (95% CI: 0.93-0.98) and 0.95 (95% CI: 0.93-0.97), respectively. The sensitivity and AUC values for D-dimer with a cut-off value of 500 ng/mL were 0.97 (95% CI: 0.95-0.99) and 0.94 (95% CI: 0.92-0.96), respectively. In contrast, microRNA had a better specificity value for AD, at 0.79 (95% CI: 0.73-0.83).

CONCLUSIONS

D-dimer and microRNA have good accuracy in the diagnosis of AD, but the specificity of D-dimer is worse, and studies of microRNA are insufficient. The combination of different biomarkers can improve the diagnostic accuracy. Other blood biomarkers are related to the pathological progression of AD and can be selected according to pathological progress.

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.

De Winter electrocardiogram pattern due to type A aortic dissection: a case report

Background

De Winter electrocardiograph (ECG) pattern is an atypical presentation of acute myocardial infarction (AMI) due to severe stenosis of the left anterior descending (LAD). Complications of acute aortic dissection (AD) in the setting of acute myocardial infarction (AMI) with de Winter sign are relatively rare and physicians may easily miss the diagnosis of AD. We report a case of patient with acute chest pain and de Winter ECG pattern due to AD involving the left main coronary artery (LM), LAD and left circumflex artery (LCX).

Case presentation

A 57-year-old male patient was initially diagnosed with AMI and then the diagnosis of acute AD was supported by transthoracic echocardiograph (TTE). After two stents were implanted respectively into the proximal LM-LAD and LM-LCX, he recovered from cardiogenic shock. Two months later, the patient underwent the surgery of ascending aorta replacement. After the surgery, there was no obvious chest discomfort during follow-up.

Conclusions

When an ECG shows a “de Winter pattern”, we should also consider the possibility of AD which result in LAD occlusion. TTE is a useful tool in screening for AD. Further research is needed to prove that percutaneous coronary intervention (PCI) may be a useful treatment strategy in the case of AD leading to severe LAD occlusion and unstable hemodynamics when there’s no condition to perform aortic replacement surgery immediately.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02596-8.

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.

Misdiagnosis of Thoracic Aortic Disease Occurs Commonly in Emergency Transfers

BACKGROUND

Acute aortic syndromes (AAS) are prone to misdiagnosis by facilities with limited diagnostic experience. We assessed long-term trends in misdiagnosis among patients transferred to a tertiary care facility with presumed AAS.

METHODS

Our institutional transfer center database was queried for emergency transfers in patients with a diagnosis of acute aortic syndromes or thoracic aortic aneurysm between January 2008 and May 2018. 784 patients were classified as emergency transfer for presumed AAS. Transferring diagnosis and actual diagnosis were compared through a review of physician notes and radiology reports from referring facilities and our center.

RESULTS

Mean age was 62 years, with 61% (n=478) men. Differences in transferring diagnosis and actual diagnosis were identified in 89 (11.4%) patients. Among misdiagnosed patients, the wrong classification of Stanford Type A or Type B dissections was identified among 24 (27%) patients. Twenty-three (26%) patients with a referring diagnosis of aortic dissection were found to have no dissection. Eighteen patients (20%) transferred for contained/impending rupture did not have signs of rupture. All misdiagnoses were secondary to misinterpretation of radiographic imaging, with motion artifacts (n=14, 16%) and post-surgical changes (n=22, 25%) being common sources of diagnostic error. Sixty-four (72%) patients underwent repeat scans at our facility due to limited access or sub-optimal quality of outside imaging.

CONCLUSIONS

While AAS misdiagnosis rates appear to be improving from the prior decade, there are opportunities for improved physician awareness through campaigns such as "Think Aorta." Centralized web-based imaging may prevent the costly hazards of unnecessary emergency transfer.

Nomogram to differentiate between aortic dissection and non-ST segment elevation acute coronary syndrome: a retrospective cohort study

Background

Aortic dissection (AD) and non-ST segment elevation acute coronary syndrome (ACS) are two of the most life-threatening diseases encountered in the emergency department (ED), but there are no rapid and reliable tools for differentiation. The purpose of this study is to develop and validate a nomogram that incorporates both the clinical characteristics and bedside laboratory tests available to differentiate between AD and non-ST segment elevation ACS (NSTE-ACS).

Methods

Between January 2016 and July 2018, patients with AD and NSTE-ACS were enrolled and divided into training and validation groups. The least absolute shrinkage and selection operator (LASSO) regression model was used to select the factors with significant value of predicting the diagnosis of AD. A nomogram was built on the basis of multivariable logistic regression analysis. Area under the curve (AUC) of receiver operating characteristic (ROC) curve and the calibration curve were used to assess the performance of the nomogram. Decision curve analysis was performed to assess the clinical utility of the nomogram.

Results

A final cohort of 263 patients (94 patients with AD and 169 patients with NSTE-ACS) were enrolled. Six variables were incorporated in the nomogram: pain severity, tearing pain, pulse asymmetry, electrocardiogram (ECG), D-dimer level and troponin I level. The AUC of the nomogram to predict the probability of AD was 0.919 (95% CI, 0.876-0.962) in the training group and 0.938 (95% CI, 0.888-0.989) in the validation group. The calibration curve demonstrated a good consistency between the actual clinical results and the predicted outcomes. The decision curve analysis indicated that the nomogram had higher overall net benefits in predicting AD in both the training group and the validation group.

Conclusions

We developed and validated a predictive nomogram that could be used as a tool to differentiate AD from NSTE-ACS rapidly and accurately.

Potential Utility of Non-gated Enhanced Computed Tomography for an Early Diagnosis of Myocardial Infarctions

The diagnosis of acute myocardial infarctions (MIs) is challenging when no significant ischemic ST-segment changes are noted on a 12-lead electrocardiogram (ECG). We herein report two patients suffering from chest pain in whom non-gated enhanced computed tomography (CT) images were used to rule out aortic dissection and pulmonary embolism, aiding in the early diagnosis of an acute MI. Subsequently, urgent revascularization was successfully performed in these patients. In non-gated enhanced CT imaging, the infarcted myocardium is initially visible as a focal myocardial perfusion defect.

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.

The diagnostic accuracy of the mediastinal width on supine anteroposterior chest radiographs with nontraumatic Stanford type A acute aortic dissection

Background

Nontraumatic Stanford type A acute aortic dissection is a life‐threatening condition; thus, the ability to make a precise diagnosis of nontraumatic Stanford type A acute aortic dissection is essential for the emergency physician. Several reports have shown that the mediastinal widening on a chest radiograph is useful for the diagnosis of nontraumatic Stanford type A acute aortic dissection; however, the exact cutoff value of the mediastinal width on plain radiographs is rarely defined.

Methods

A single‐center retrospective case‐control study was conducted between October 1, 2013, and March 31, 2015. We evaluated the maximal mediastinal width of the anteroposterior chest X‐ray at the level of the aortic knob in the supine position between patient groups with and without nontraumatic Stanford type A acute aortic dissection.

Results

We enrolled 72 patients (36 patients with nontraumatic Stanford type A acute aortic dissection and 36 patients without nontraumatic Stanford type A acute aortic dissection). The median mediastinal width of patients with nontraumatic Stanford type A acute aortic dissection was significantly larger than that of patients without nontraumatic Stanford type A acute aortic dissection (100.7 mm vs 77.7 mm, P < .01). The optimal cutoff level was 87 mm (sensitivity, 81%; specificity, 89%). Using multivariable logistic regression, the odds ratio of a mediastinal width of >87 mm for a diagnosis nontraumatic Stanford type A acute aortic dissection was 57.1 (95% confidence interval, 11.2‐290.2).

Conclusion

A mediastinal width of >87 mm showed high sensitivity in the diagnosis of probable nontraumatic Stanford type A acute aortic dissection.

Cardiovascular Disease in Ageing: An Overview on Thoracic Aortic Aneurysm as an Emerging Inflammatory Disease

Medial degeneration associated with thoracic aortic aneurysm and acute aortic dissection was originally described by Erdheim as a noninflammatory lesion related to the loss of smooth muscle cells and elastic fibre fragmentation in the media. Recent evidences propose the strong role of a chronic immune/inflammatory process in aneurysm evocation and progression. The coexistence of inflammatory cells with markers of apoptotic vascular cell death in the media of ascending aorta with aneurysms and type A dissections raises the possibility that activated T cells and macrophages may contribute to the elimination of smooth muscle cells and degradation of the matrix. On the other hand, several inflammatory pathways (including TGF-β, TLR-4 interferon-γ, chemokines, and interferon-γ) seem to be involved in the medial degeneration related to aged and dilated aorta. This is an overview on thoracic aortic aneurysm as an emerging inflammatory disease.

Admission D-dimer testing for differentiating acute aortic dissection from other causes of acute chest pain

INTRODUCTION

The present study aims to evaluate the utility of D-dimer testing for differentiating the causes of acute chest pain, including acute aortic dissection (AAD), pulmonary embolism (PE), acute myocardial infarction (AMI), unstable angina (UA), and other uncertain diagnoses of chest pain.

MATERIAL AND METHODS

Consecutive patients admitted for acute chest pain within 24 h from symptom onset were enrolled prospectively, and plasma D-dimer levels were measured on admission. Diagnoses of AAD, PE, AMI, and UA were confirmed by standard methods.

RESULTS

A total of 790 patients were enrolled, including 202 AAD, 43 PE, 315 AMI, 136 UA, and 94 cases of other uncertain diagnoses. D-dimer levels were significantly higher in patients with AAD and PE than in those with AMI, UA, and other uncertain diagnoses (p < 0.001), but they were comparable between patients with AAD and PE (p = 0.065). Moreover, patients with type A AAD had higher D-dimer levels than those with type B AAD (p = 0.022). Receiver operating characteristic (ROC) curve analysis showed that a D-dimer level < 0.5 µg/ml was a good predictor for ruling out AAD, with a sensitivity of 94.0% and a specificity of 56.8%. At a cut-off level of 0.5 µg/ml, the negative and positive likelihood ratios were 0.10 and 2.18, respectively, with a positive predictive value of 42.6% and a negative predictive value of 96.6%.

CONCLUSIONS

The D-dimer level within 24 h after symptom onset might be helpful for differentiating AAD from other causes of chest pain.

Biomarkers Investigation for In-Hospital Death in Patients With Stanford Type A Acute Aortic Dissection

This retrospective study aimed to investigate the predictive value of biomarkers for in-hospital mortality of patients with Stanford type A acute aortic dissection (AAD).AAD is a life-threatening disease with an incidence of about 2.6-3.6 cases per 100,000/year.A total of 67 consecutive Stanford type A AAD patients admitted to hospital were divided into a deceased group and survival group. The baseline information of the patients between two groups was systematically compared, followed by examination of the electrocardiograms (ECG). Based on the follow-up during hospitalization, we investigated the simultaneous assessment of indexes like fragmented QRS complex (fQRS), admission systolic blood pressure (SBP), aortic diameter, surgical management, troponin I (TnI), white blood cell (WBC) count, N-terminal pro-brain natriuretic peptide (NT-proBNP), and D-dimer.The levels of TnI and NT-proBNP, WBC counts, and rate of fQRS (+) in patients of the deceased group were significantly higher than those in the survival group. The male sex (hazard ratio, 10.88; P = 0.001), admission SBP (hazard ratio, 0.98; P = 0.012), NT-proBNP (hazard ratio, 1.00; P = 0.001), and WBC count (hazard ratio, 1.10; P = 0.033) were independently related with in-hospital death. As a single marker, WBC count had the highest sensitivity at 84.6% (specificity 65.9%).Admission SBP, NT-proBNP, and WBC count were potential independent risk factors of in-hospital death in Stanford type A AAD patients. WBC count may be a more accurate predictor of type A AAD than either alone.

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.

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.

[Risk evaluation of type B aortic dissection: importance for treatment of acute aortic syndrome]

Acute aortic syndrome (AAS) is a modern term used to describe interrelated emergency aortic conditions with similar clinical characteristics and challenges including aortic dissection, intramural hematoma (IMH) and penetrating aortic ulcer (PAU). Population-based studies suggest that the incidence of aortic dissection ranges from 2.6 to 3.5 cases per 100,000 inhabitants per year; hypertension and a variety of genetic disorders with altered connective tissue are the most prevalent risk conditions. In general, open surgical repair is recommended when dissection involves the ascending aorta, whereas medical management and endovascular stent graft repair is the best option when the ascending aorta is spared. Pathological conditions involving the aortic arch may be treated using a hybrid approach combining debranching of supra-aortic vessels and stent graft placement. Stent graft-induced remodeling of a dissected aorta seems to have long-term benefits in complicated and so-called uncomplicated type B dissections as almost every case reveals a risk profile and one in eight patients diagnosed with acute type B aortic dissection has either an IMH or a PAU. Pain is the most commonly presenting symptom of AAS and should prompt immediate attention including diagnostic imaging modalities, such as multislice computed tomography, transesophageal ultrasound and magnetic resonance imaging. A specific therapeutic approach is necessary for IMH and PAU because without treatment they have a very poor outcome, are unpredictable in evolution and can be more severe than acute aortic dissection. All patients must receive the best medical treatment available at admission. High-risk but asymptomatic patients with IMH and PAU can probably be monitored without interventions. All symptomatic patients will need treatment. In many of these patients a direct surgical approach is often prohibitive due to age and multiple comorbidities. Endovascular treatment offers superior results and is becoming a recognized indication for such patients. Irrespective of the treatment modality close surveillance is mandatory in order to monitor disease progression.

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.

Combined use of aortic dissection detection risk score and D-dimer in the diagnostic workup of suspected acute aortic dissection

BACKGROUND

Acute aortic dissection (AD) represents a diagnostic conundrum. Validated algorithms are particularly needed to identify patients where AD could be ruled out without aortic imaging. We evaluated the diagnostic accuracy of a strategy combining the aortic dissection detection (ADD) risk score with D-dimer, a sensitive biomarker of AD.

METHODS

Patients from two clinical centers with suspected AD were prospectively enrolled in a registry, from January 2008 to March 2013. The ADD risk score was calculated by retrospective blinded chart review. For D-dimer, a cutoff of 500 ng/ml was applied.

RESULTS

AD was diagnosed in 233 of 1035 (22.5%) patients. The ADD risk score was 0 in 322 (31.1%), 1 in 508 (49.1%) and >1 in 205 (19.8%) patients. The sensitivity and the failure rate of D-dimer were 100% and 0% in patients with ADD score 0, versus 97.5% (95% CI 91.4-99.6%) and 4.2% (95% CI 0.7-12.5%) in patients with ADD risk score >1. In patients with ADD risk score ≤ 1, the sensitivity and the failure rate of D-dimer were 98.7% (95% CI 95.3-99.8%) and 0.8% (95% CI 0.1-2.6%). The diagnostic efficiency of D-dimer in patients with ADD risk score 0 and ≤ 1 was 8.9% (95% CI 7.2-10.7%) and 23.6% (95% CI 21.1-26.2%) respectively.

CONCLUSIONS

In a large cohort of patients with suspected AD, the presence of ADD risk score 0 or ≤ 1 combined with a negative D-dimer accurately and efficiently ruled out AD.

The ratio of D-dimer to brain natriuretic peptide may help to differentiate between cerebral infarction with and without acute aortic dissection

BACKGROUND

Previous studies reported that the plasma d-dimer level reflects the activity of thrombus formation in the left atrium of patients with acute cerebral infarction and acute aortic dissection (AAD). Brain natriuretic peptide (BNP) is considered to be a marker of chronic heart failure. The differential diagnosis in the emergency room between stroke due to cardioembolism and AAD is difficult but important for early treatment especially in patients requiring intravenous thrombolysis with a recombinant tissue-type plasminogen activator. We aimed to investigate the association between the plasma d-dimer and BNP levels in patients with cerebral infarction and AAD.

METHODS

We identified 115 consecutive patients with ischemic stroke who were admitted within 72 h of symptom onset and 15 consecutive patients with AAD and measured the level of plasma d-dimer and BNP and the d-dimer:BNP ratio.

RESULTS

In patients with AAD the d-dimer level was significantly higher than that in patients with any other stroke subtypes and their BNP level was significantly lower than that in patients with cardioembolic stroke. The d-dimer:BNP ratio was significantly higher in patients with AAD than in those with any other stroke subtype. Compared to patients with a cardioembolic stroke subtype they manifested significantly higher d-dimer levels and d-dimer:BNP ratios suggesting that this ratio may help to diagnose cerebral infarction due to AAD (sensitivity 80%, specificity 93.5%, cut-off 0.074). When the population was limited to patients within 6h of onset, the ratio had higher sensitivity and specificity at the same cut-off value (sensitivity 81.8%, specificity 96.4%).

CONCLUSION

We found that the d-dimer:BNP ratio may be helpful in distinguishing between cerebral infarction with and without AAD.

Renal dysfunction on admission as a predictor for in-hospital mortality of patients with stanford type B acute aortic dissection

Stanford type A and open false lumen are accepted predictors for in-hospital mortality in patients with acute aortic dissection (AAD). However, the association of renal dysfunction on admission with in-hospital mortality is not well known. The aim of this study was to investigate the prognostic value of renal dysfunction in patients with AAD. A total of 250 patients with type B AAD admitted to our institution between January 2003 and August 2011 were enrolled in this study. In multivariate logistic regression analysis, the significant predictors of in-hospital mortality were age (odds ratio [OR] 1.575, 95% confidence interval [CI] 1.078-2.864, p = 0.024), maximum aortic diameter measured by an initial computed tomography (CT) (OR 1.740, 95% CI 1.029-2.940, p = 0.039), decreased enhancement of kidney (OR 7.716, 95% CI 2.335-25.501, p = 0.001) and estimated glomerular filtration rate (eGFR) <60 ml/min/1.73m(2) on admission (OR 2.782, 95% CI 1.062-7.283, p = 0.037). In conclusions the results identified a renal dysfunction on admission as the independent predictor of in-hospital mortality in type B AAD. Further investigations are needed to evaluate therapies and strategies for decreasing the deterioration of renal function to improve in-hospital mortality in patients with AAD.

Novel biomarkers for risk stratification and identification of life-threatening cardiovascular disease: troponin and beyond

Chest pain and other symptoms that may represent acute coronary syndromes (ACS) are common reasons for emergency department (ED) presentations, accounting for over six million visits annually in the United States [1]. Chest pain is the second most common ED presentation in the United States. Delays in diagnosis and inaccurate risk stratification of chest pain can result in serious morbidity and mortality from ACS, pulmonary embolism (PE), aortic dissection and other serious pathology.

Because of the high morbidity, mortality, and liability issues associated with both recognized and unrecognized cardiovascular pathology, an aggressive approach to the evaluation of this patient group has become the standard of care. Clinical history, physical examination and electrocardiography have a limited diagnostic and prognostic role in the evaluation of possible ACS, PE, and aortic dissection, so clinicians continue to seek more accurate means of risk stratification. Recent advances in diagnostic imaging techniques particularly computed-tomography of the coronary arteries and aorta, have significantly improved our ability to diagnose life-threatening cardiovascular disease.

In an era where health care utilization and cost are major considerations in how disease is managed, it is crucial to risk-stratify patients quickly and efficiently. Historically, biomarkers have played a significant role in the diagnosis and risk stratification of several cardiovascular disease states including myocardial infarction, congestive heart failure, and pulmonary embolus. Multiple biomarkers have shown early promise in answering questions of risk stratification and early diagnosis of cardiovascular pathology however many do not yet have wide clinical availability. The goal of this review will be to discuss these novel biomarkers and describe their potential role in direct patient care.

Biological features of thoracic aortic diseases. Where are we now, where are we heading to: established and emerging biomarkers and molecular pathways

Thoracic aortic aneurysms (TAAs) and aortic dissections (ADs) are among the main causes of mortality and morbidity in Western countries. For this reason, the diagnosis, prevention and prediction of TAAs and ADs have become a very active area of research; in fact, it is important to monitor and predict the evolution of these diseases over time. It is also critical, in cases of doubtful diagnosis, to receive some guidance from biochemical assays, particularly in the case of ADs. Although biological testing for disease prediction has already been discussed several times, the role of biomarkers in TAAs and ADs is still under discussion for routine patient screening, periodical follow-up or for prompt diagnosis in emergency conditions. In this review, we update the current knowledge and new trends regarding the role of biomarkers in thoracic aortic diseases, focusing on established and emerging biomarkers in the fields of genetics, inflammation, haemostasis and matrix remodelling as well as on substances released upon cell damage. Other than D-dimer, a sensitive but not a specific marker for the diagnosis of AD that has been widely tested by several authors and currently seems a viable option in ambiguous cases, the remaining markers have been most frequently assessed in limited or mixed patient populations. This currently precludes their widespread adoption as diagnostic or prognostic tools, even if many of these markers are conceptually promising. In years to come, we expect that future studies will further clarify the diagnostic and prognostic features of several established and emerging biomarkers that, to date, are still in the translational limbo separating biological discovery from a practical clinical role.

Current imaging techniques and potential biomarkers in the diagnosis of acute aortic dissection

Acute dissection of the thoracic aorta (AAD) is a potentially catastrophic disease, with significant morbidity and mortality, which remain unchanged over the last decade. Survival rate has been shown to be directly related to prompt diagnosis and precise management; however diagnosis of the disease remains time-consuming, not readily available, and lacking in sensitivity and specificity. The current approach when diagnosing AAD relies heavily on various imaging techniques, including chest radiograph, echocardiography, computed tomography and magnetic resonance imaging scans. Nevertheless, the door remains open for the incorporation of biochemical tests to aid in detecting AAD. This article will review the imaging modalities currently employed in the management of AAD, as well as a discussion of the potential role of several biomarkers in AAD. To date, imaging is the diagnostic tool for AAD however, technical and logistical limitations limit the use of imaging in various circumstances. Current available biomarkers such as D-dimer and C-reactive protein are under-utilized in many cases, mainly due to their non-specificity in diagnosing AAD. Over the last decade, many biomarkers have been proposed for use in AAD, with several showing promising results – including: smooth muscle myosin heavy chain, calponin, soluble elastin fragments and transforming growth factor β. Extensive research is being undertaken to define the roles of these novel biomarkers in the management of AAD.

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.

Biomarkers in aortic dissection

Aortic dissection (AD) is a severe cardiovascular disease with high mortality and morbidity, which is characterized by acute onset and rapid progress. Mechanically, it has been considered that circulating blood flows into the media of the aorta through the rupture of the intima forming true and false lumens. Generally, its pathologic process is considered as follows: initially, inflammatory reaction, inflammatory cells infiltration in aortic wall, and then apoptosis of vascular smooth muscle cells, degenerating of aortic media, elastin fracture, and degradation. At last, the ingredients of the aorta are destroyed and lead to aortic dilatation, aneurysm formation, dissection and rupture. Currently, several biomarkers in peripheral blood including C-reactive protein (CRP), matrix metalloproteinases (MMPs), soluble elastin fragments (sELAF), D-dimer, smooth muscle myosin heavy chain, calponin, N-terminal pro-brain natriuretic peptide (NT-proBNP), big endothelin-1 (Big ET-1), genetic markers and so on, have been demonstrated to play a major role in evaluation of AD, for example, making early diagnosis and classifying of AD. Additionally, those markers may also guide our treatment therapies and predict the prognosis. The aims of this review mainly focus on the clinical implications of the biomarkers in AD.

Diagnosing acute aortic syndromes: the role of specific biochemical markers

Acute aortic syndromes (AAS) remain one of the most challenging medical emergencies. Making a prompt and accurate diagnosis is a race against time, where delay may be disastrous for the patient's life. Prompt and accurate diagnosis using imaging modalities has been available for many years, but the major concern is how the clinician's suspicion should be aroused concerning the possibility of an acute aortic syndrome, especially in cases of atypical clinical presentation and/or poor signs during clinical examination. Since the first case report publication in 1995, novel biochemical markers have been used for the rapid diagnosis of AAS, such as smooth muscle myosin heavy chains, serum soluble elastin fragments, and d-dimers, with the latter being the most widely used in clinical trials. Despite their potential, all these substances need to be re-evaluated in large randomized trials before they can be included as biomarkers of high sensitivity and specificity in clinical practice.

Diagnosis of Acute Aortic Dissection by D-Dimer

Background— D-dimer has been reported to be elevated in acute aortic dissection. Potential use as a “rule-out” marker has been suggested, but concerns remain given that it is elevated in other acute chest diseases, including pulmonary embolism and ischemic heart disease. We evaluated the diagnostic performance of D-dimer testing in a study population of patients with suspected aortic dissection.

Methods and Results— In this prospective multicenter study, 220 patients with initial suspicion of having acute aortic dissection were enrolled, of whom 87 were diagnosed with acute aortic dissection and 133 with other final diagnoses, including myocardial infarction, angina, pulmonary embolism, and other uncertain diagnoses. D-dimer was markedly elevated in patients with acute aortic dissection. Analysis according to control disease, type of dissection, and time course showed that the widely used cutoff level of 500 ng/mL for ruling out pulmonary embolism also can reliably rule out aortic dissection, with a negative likelihood ratio of 0.07 throughout the first 24 hours.

Conclusion— D-dimer levels may be useful in risk stratifying patients with suspected aortic dissection to rule out aortic dissection if used within the first 24 hours after symptom onset.

The triple work-up for emergency department patients with acute chest pain: how often does it occur?

OBJECTIVES

To measure the degree of overlap and diagnostic yield for evaluations of acute coronary syndrome (ACS), pulmonary embolism (PE), and aortic dissection (AD) among Emergency Department (ED) patients.

METHODS

We conducted a cross-sectional descriptive study of consecutive adult patients seen in the ED of a 78,000-annual-visit urban academic medical center. Patients who had received at least one of eight of the tests used in our ED to diagnose these three diseases were identified through three methods, and a final study population list was created. Overlap of evaluations and diagnostic yields were calculated by simple descriptive statistics.

RESULTS

Over a 2-week period, 626 patient encounters among 622 unique patients were identified. Among these 626 visits, 139 (22%) included diagnostic tests for more than one of the three diagnoses of interest. The majority of these multiple tests were for ACS plus PE (n = 121, 87% of all multiple tests), whereas a minority of patients received tests for ACS plus AD (n = 14, 10% of all multiple tests) or for the "triple work-up" of ACS plus PE plus AD (n = 4, 2.9% of all multiple tests).

CONCLUSION

Although the "triple work-up" evaluation for ACS, PE, and AD is relatively uncommon, a significant number of ED patients who are evaluated for at least one of these three major chest pain syndromes receive simultaneous testing for one of the others.

Litigation in Nontraumatic Aortic Diseases – A Tempest in the Malpractice Maelstrom

OBJECTIVES

Physicians are vulnerable to highly litigated thoracic aortic diseases. On the basis of a review of litigated cases, we aim to determine legally protective strategies for physicians and methods to improve treatment.

METHODS

Thirty-three nontraumatic, thoracic aorta-related legal cases were analyzed.

RESULTS

Twenty-three patients (69.7%) had dissections (21 ascending, 2 descending), 8 (24.2%) had aneurysms and 2 had miscellaneous other phenomena (1 coarctation and 1 iatrogenic descending aortic rupture). The adverse event was death in 30 (90.9%) patients and paraplegia or stroke in 3 (9.1%). Allegations included: failure/delay in diagnosis (19), delay in surgery (4), error in surgical technique (5), failure to prevent paraplegia (2) and miscellaneous (3). Medical treatment was retrospectively judged suboptimal in 22 cases (66.6%) for reasons consonant with allegations.

CONCLUSIONS

Aortic disease can be diagnostically elusive, as 'the great masquerader'. Emergency physicians must maintain a high index of suspicion for aneurysm and dissection. The D-dimer test can effectively rule out aortic dissection. 'Triple rule-out' CT scans should be performed liberally. CT scan readers must remember to evaluate the aorta. Operating room administrators must be aware that postponing a scheduled thoracic aortic case may result in interim rupture and consequent litigation. With virulent thoracic aortic diseases, adverse outcome itself does not imply substandard care.