D-dimers are not always elevated in patients with acute aortic dissection

Analysis of clinical characteristics and imagological features of the aortic dissection patients with negative D-dimer results

Background

D-dimer (DD) is a vital biomarker to rule out the diagnosis of aortic dissection (AD). However, the DD level in some patients with AD is not high in clinical practice, which often leads to missed diagnosis; therefore, understanding the characteristics of patients with AD and negative DD is of great clinical value.

Methods

From May 2015 to October 2020, 286 patients with AD who visited the first medical contact (FMC) within 24 h of symptom onset and were hospitalized in the Xiamen Cardiovascular Hospital of Xiamen University were enrolled in this study. Clinical characteristics and outcomes of patients were assessed.

Results

Among them, 13 cases (approximately 4.5%) had negative DD results. Compared to patients with positive DD results, patients with negative DD results had significantly higher platelet counts and lower aortic dissection detection risk scores (ADD-RS). The imagological analysis showed that patients with AD and negative DD had lower extension scores and milder damage to the mesenteric artery and three branches of the aortic arch. Furthermore, the results of the multivariable analysis showed that white blood cell count (WBC) [odds ratio (OR): 1.379, P = 0.028], FMC (OR: 0.904, P = 0.028), and extension score (OR: 1.623, P = 0.046) were associated with negative DD result.

Conclusions

Patients with AD and negative DD results had longer FMC and lower WBC. Imaging showed a smaller tear extension range and less damage to the mesenteric artery and three branches of the aortic arch. A negative DD result could not completely rule out AD even if the ADD-RS was zero.

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.

Efficacy of CRP in combination with D-dimer in predicting adverse postoperative outcomes of patients with acute Stanford type A aortic dissection

Purpose

The present study evaluated the efficacy of C-reactive protein (CRP) and D-dimer and the combination of them as prognostic indicators for patients with acute type A aortic dissection (ATAAD).

Methods

This is a retrospective cohort study. From January 2019 to December 2021, patients with ATAAD admitted to the emergency medicine center of our hospital within 24 h after symptoms (chest pain, back pain, abdominal pain and so on) onset were enrolled in our study. Serum concentration of CRP and D-dimer were measured during hospitalization. Logistic regression was used to evaluate the association between these two biomarkers and in-hospital adverse outcomes (IAO) by adjusting confounding factors. Predictive efficacy was assessed by area under the curve (AUC) of receiver operating characteristic curve.

Results

A total of 199 patients with ATAAD were finally enrolled. They were categorized as Non-IAO group (n = 146) and IAO group (n = 53) according to postoperative outcomes. After controlling for potentially confounding variables, we found categorized variables that admission CRP > 54.28 mg/L, admission D-dimer > 8.45 mg/L and peak D-dimer > 24.89 mg/L were independent predictors of in-hospital adverse outcomes. Multiple Logistic regression analysis revealed that the odd ratios were 2.9 for admission D-dimer > 8.45 [95% Confidence Interval (CI) 1.11–7.5, p = 0.03], 4.9 for admission CRP > 54.28 (95% CI 1.6–14.9, p = 0.005) and 5.7 for peak D-dimer > 24.89 (95% CI 2.49–13, p < 0.001). The predictive accuracy of the combination of three categorized variables (AUC: 0.867, 95% CI 0.813–0.921, p < 0.001) was superior to that of any other one alone.

Conclusion

Admission D-dimer > 8.45 mg/L, peak D-dimer > 24.89 mg/L and admission CRP > 54.28 mg/L are independent predictors of in-hospital adverse outcomes in patients with ATAAD. Combination of these three markers will improve the predictive efficacy.

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.

Relationship of Platelet Counts and Inflammatory Markers to 30-Day Mortality Risk in Patients with Acute Type A Aortic Dissection

Markers of prothrombotic state and inflammation are associated with the prognosis of patients with acute type A aortic dissection (AAAD). However, it is unclear that the relationship between these biomarkers and their combined impact on risk stratification. The present study evaluated the prognostic value of platelet counts, lymphocyte to neutrophil ratio (LNR), and lymphocyte to monocyte ratio (LMR), alone and in combination. A retrospective analysis of clinical data of 744 AAAD patients was conducted to identify whether these biomarkers were related to the 30-day mortality risk. A Kaplan-Meier analysis and log-rank test were used to compare survival between groups. A Cox hazard regression multivariable analysis was performed for 30-day mortality. Individual biomarker (platelet count, LNR, or LMR) was unable to predict 30-day mortality. However, combinations of all three biomarkers provided additive predictive value over either marker alone, the receiver operating characteristic (ROC) model had a prediction probability of 0.739 when platelet counts, LNR, and LMR were included. Cox hazard regression multivariable analysis showed that combinations of all three biomarkers were the strongest predictor of 30-day mortality (p < 0.021). Combined with these three easily measurable biomarkers at admission, they could help identify AAAD patients with a high risk of 30-day mortality.

Impact of a negative D-dimer result on the initial assessment of acute aortic dissection

BACKGROUND

D-dimer shows high sensitivity but low specificity for the diagnosis of acute aortic dissection (AAD). Previous reports indicated that negative D-dimer patients have shorter dissection length. However, whether patients with negative D-dimer results have a good prognosis is unknown. This study aimed to elucidate the clinical characteristics and implications of a negative D-dimer result on AAD diagnosis.

METHODS

The study group comprised 126 patients (71 males, 55 females; mean age, 69 ± 11 years) with AAD admitted to our hospital between April 2009 and March 2015. Blood samples on presentation were used for D-dimer measurement. Clinical characteristics and outcomes were assessed.

RESULTS

Nine (7.1%) and 117 (92.9%) exhibited negative and positive D-dimer results, respectively. The negative group showed a significantly lower extension score and a higher platelet count than the positive group. Multivariate analysis demonstrated that platelet count (odds ratio, 1.31 (1.09-1.58), p = 0.003) and extension score (odds ratio, 0.56 (0.33-0.96), p = 0.03) were significantly related to a negative result. Notably, 44% of patients in the negative group had type A dissection and 33% underwent an emergency operation due to cardiac tamponade.

CONCLUSION

We found that high platelet count and low extension score were independent factors related to a negative D-dimer result. Even if the length of the dissection is short, an emergency operation is necessary in some patients with a negative D-dimer result. Physicians should recognize that a negative D-dimer result alone cannot exclude patients with fatal AAD conditions.

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.

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.

Plasma D-dimer and in-hospital mortality in patients with Stanford type A acute aortic dissection

Plasma D-dimer has been used as a complementary initial diagnostic marker for acute aortic dissection (AAD). However, its prognostic role in patients with Stanford type A AAD has not been clarified. We prospectively enrolled a consecutive series of patients with suspect AAD presented to our emergency department and measured the plasma D-dimer level (Stago-evolution, France) immediately following the admission. The diagnosis of type A AAD was confirmed by aorta angiography with multidetector computed tomography for each patient. Patients were divided into two groups: the deceased group, who died during hospitalization, and the survival group. The predictive value of D-dimer for in-hospital mortality was determined by using univariate and multivariate Cox proportional hazards analyses. A total of 133 patients with Stanford type A AAD were included. During hospitalization, death occurred in 19 (14.3%) patients. The average hospitalization period was 12.2 days. The plasma D-dimer level of the deceased group was significantly higher than that of the survival group (14.7 ± 8.1 vs. 9.0 ± 7.2 μg/ml, P = 0.003). The in-hospital mortality was significantly higher in patients with plasma D-dimer level of at least 20 μg/ml than in those with plasma D-dimer level less than 20 μg/ml (32.3 vs. 7.5%, log rank P < 0.001). In patients not receiving surgical treatment, the in-hospital mortality was significantly higher in patients with plasma D-dimer of at least 20 μg/ml than that in those with plasma D-dimer less than 20 μg/ml (52.4 vs. 16.7%, P = 0.007). After adjustment for age, systolic blood pressure, platelet counts, and intervals from symptom onset to hospital, a high admission D-dimer level (≥20 μg/ml) was still a powerful independent predictor of in-hospital mortality (hazard ratio 3.195, 95% confidence interval 1.110-9.196, P = 0.031). However, the predictive value of high admission D-dimer level disappeared when surgery was added to the Cox multivariate model. Our results suggest a high admission D-dimer level (≥20 μg/ml) might be a powerful predictor for increased in-hospital mortality in patients with Stanford type A AAD, and these patients may benefit more from surgical intervention.

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.

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.

Using fibrin degradation products level to facilitate diagnostic evaluation of potential acute aortic dissection

This study evaluated whether degradation products of plasma fibrin and fibrinogen (FDP) level can be used to differentiate acute aortic dissection (AAD) from acute myocardial infarction (AMI), angina pectoris, acute cerebral infarction, or transient cerebral ischemic attack (TIA). Ninety-six consecutive patients with definitive diagnosis of AAD by contrast-enhanced computed tomography scan underwent measurement of FDP on admission. Of these patients, 45 had a patent false lumen (patent-type), and 51 had complete thrombosis of the false lumen (thrombosed-type). Control groups were patients admitted during the same period for whom a diagnosis of either AMI (n = 187), angina pectoris (n = 142), cerebral infarction (n = 353), or TIA (n = 94) was confirmed. FDP was significantly higher in patients with patent-type AAD (median, 210 μg/mL; interquartile range, 70-358 μg/mL) than in those with thrombosed-type AAD (16.5, 7.2-50.1). Patients with patent-type AAD or thrombosed-type AAD had a significantly higher FDP than patients in any of the control groups. Receiver operating characteristic curve analysis indicated that FDP ≥ 12.6 μg/mL was the cutoff value that best differentiated patients with patent-type AAD from patients in any of the control groups (sensitivity, 100%; negative predictive value [NPV], 100%). And, this FDP cutoff level was associated with a high positive predictive value (PPV) (80-92%). The cutoff value to differentiate patients with thrombosed-type AAD from patients in any of the control groups was FDP ≥ 5.6 μg/mL (sensitivity, 100%; NPV, 100%). However, this FDP cutoff level was associated with a low PPV (36-81%). FDP and D-dimer were measured at the same time on admission in 30 patients with AAD and 41 patients in control groups. A simple liner regression, calculated using FDP and D-dimer values from a total of 71 patients, yielded a correlation coefficient (R2) of 0.95, indicating a strong correlation. In symptomatic patients with suspected AAD, a diagnosis of patent-type AAD should be considered if FDP ≥ 12.6 μg/mL. Patients with FDP ≥ 5.6 μg/mL have the possibility of thrombosed-type AAD.

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.

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.

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.