Biomarkers for diagnosis and prognostic stratification of aortic dissection: challenges and perspectives

Anti-inflammatory response-based risk assessment in acute type A aortic dissection: A national multicenter cohort study

Background

Early identification of patients at high risk of operative mortality is important for acute type A aortic dissection (TAAD). We aimed to investigate whether patients with distinct risk stratifications respond differently to anti-inflammatory pharmacotherapy.

Methods

From 13 cardiovascular hospitals, 3110 surgically repaired TAAD patients were randomly divided into a training set (70%) and a test set (30%) to develop and validate a risk model to predict operative mortality using extreme gradient boosting. Performance was measured by the area under the receiver operating characteristic curve (AUC). Subgroup analyses were performed by risk stratifications (low versus middle-high risk) and anti-inflammatory pharmacotherapy (absence versus presence of ulinastatin use).

Results

A simplified risk model was developed for predicting operative mortality, consisting of the top ten features of importance: platelet-leukocyte ratio, D-dimer, activated partial thromboplastin time, urea nitrogen, glucose, lactate, base excess, hemoglobin, albumin, and creatine kinase-MB, which displayed a superior discrimination ability (AUC: 0.943, 95 % CI 0.928-0.958 and 0.884, 95 % CI 0.836-0.932) in the derivation and validation cohorts, respectively. Ulinastatin use was not associated with decreased risk of operative mortality among each risk stratification, however, ulinastatin use was associated with a shorter mechanical ventilation duration among patients with middle-high risk (defined as risk probability >5.0 %) (β -1.6 h, 95 % CI [-3.1, -0.1] hours; P = 0.048).

Conclusion

This risk model reflecting inflammatory, coagulation, and metabolic pathways achieved acceptable predictive performances of operative mortality following TAAD surgery, which will contribute to individualized anti-inflammatory pharmacotherapy.

MiR-590-3p Promotes the Phenotypic Switching of Vascular Smooth Muscle Cells by Targeting Lysyl Oxidase

ABSTRACT

We investigated the clinical characteristics of patients with acute aortic dissection (AAD) and miR-590-3p levels in serum, tissue, and vascular smooth muscle cells. The effect of miR-590-3p on the vascular smooth muscle cell phenotype was assessed, and the regulation of lysyl oxidase by miR-5903p was determined. C57BL/6 mice were used to investigate the incidence of AAD and effects of miR-5903p on AAD. The miR-590-3p levels were measured in the aortae of mice, and hematoxylin and eosin staining and Masson staining were performed to identify the morphological features of the aorta. Comparative analysis revealed significant differences in clinical characteristics between patients with AAD and healthy control subjects, with most patients with AAD exhibiting concomitant hypertension and nearly 50% having atherosclerosis. Lysyl oxidase was a direct target of miR-590-3p. Lysyl oxidase overexpression inhibited switching of the vascular smooth muscle cell phenotype from contractile to synthetic, but miR-590-3p overexpression significantly reversed this change. In the mouse model, miR-590-3p upregulation increased the incidence of AAD to 93.3%, and its incidence decreased to 13.3% after miR-590-3p inhibition. Hematoxylin and eosin and Masson staining revealed that the miR-590-3p agomiR group had a greater loss of the contractile phenotype in the dissected aortic wall and an increased number of muscle fibers in the aortic wall, which contributed to thickening of the aortic wall and the formation of a false lumen in aortic dissection. miR-590-3p might be pivotal in the pathogenesis of AAD. Thus, targeting miR-590-3p or its downstream pathways could represent a therapeutic approach for AAD.

Longitudinal Assessment of Inflammatory Activity in Acute Type B Aortic Dissection with Integrated Fluorodeoxyglucose Positron Emission Tomography/Magnetic Resonance Imaging

OBJECTIVE

The significance of the inflammatory response in the natural course of acute type B aortic dissection (ATBAD) is unknown. The aim was to characterise inflammation and its transformation over time in ATBAD using 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) with contrast enhanced magnetic resonance imaging (MRI).

METHODS

Ten patients underwent FDG-PET/MRI within two weeks of ATBAD (acute phase), three to four months (subacute phase), nine to 12 months (early chronic phase), and 21 to 24 months (late chronic phase) after ATBAD. Target background ratios (TBRs) were measured in the ascending aorta, aortic arch, and descending aorta. MRI inflammatory markers were assessed in the descending aorta.

RESULTS

Ten patients were included: median age 69 years, median clinical follow up 32 months. In the acute phase there was increased FDG uptake in the descending aorta (maximum TBR 5.8, SD [standard deviation] 1.3) compared with the ascending aorta (TBR 3.3, SD 0.8, p < .010) and arch (TBR 4.2, SD 0.6, p = .010). The maximum TBR of the descending aorta decreased from the acute to subacute phase (TBR 3.5, SD 0.6, p = .010) and further to the early chronic phase (TBR 2.9, SD 0.4, p = .030) but was stable thereafter. The acute phase maximum TBR in the ascending aorta (TBR 3.3) and arch (TBR 4.2) decreased to the subacute phase (ascending: TBR 2.8, SD 0.6, p = .020; arch: TBR 2.7, SD 0.4, p = .010) and was stable thereafter. Four patients underwent surgical aortic repair (three for aortic dilatation at one, five, and 28 months and one for visceral ischaemia at three weeks). MRI signs of inflammation were present in all surgically treated patients vs. two of six of medically treated patients (p= .048).

CONCLUSION

ATBAD is associated with increased FDG uptake in the acute phase primarily in the descending aorta, but also involving the aortic arch and ascending aorta, indicating an inflammatory response in the whole aorta. Inflammation subsides early in the ascending aorta and arch (three months), whereas it stabilised later in the descending aorta (nine to 12 months). MRI signs of inflammation were more frequent in patients who later needed surgical treatment and merit further investigation.

High Serum VE-Cadherin and Vinculin Concentrations Are Markers of the Disruption of Vascular Integrity during Type B Acute Aortic Dissection

BACKGROUND

In the present study, we measured the serum vascular endothelial cadherin (VEC) and vinculin (Vcn) concentrations in patients with type B acute aortic dissection (TBAD) to evaluate their diagnostic value for this condition.

METHODS

A total of 100 patients with TBAD and 90 matched controls were included in the study. The serum concentrations of VEC and Vcn were measured using enzyme-linked immunosorbent assays.

RESULTS

The serum VEC and Vcn concentrations were significantly higher in participants with TBAD than in healthy controls. Compared with patients with acute myocardial infarction (AMI), the serum concentrations of VEC and Vcn in patients with TBAD were higher, and the Vcn showed significant difference, with statistical significance. Receiver operating characteristic analysis generated areas under the curves for VEC and Vcn that were diagnostic for TBAD (0.599 and 0.655, respectively). The optimal cut-off values were 3.975 ng/μL and 128.1 pg/mL, the sensitivities were 43.0% and 35.0%, and the specificities were 73.3% and 90.0%, respectively. In addition, the use of a combination of serum VEC and Vcn increased the AUC to 0.661, with a sensitivity of 33.0% and a specificity of 93.33%. A high serum Vcn concentration was associated with a higher risk of visceral malperfusion in participants with TBAD (odds ratio (OR) = 1.007, 95% confidence interval [CI]: 1.001-1.013, p = 0.014). In participants with refractory pain, the adjusted OR for the serum VEC concentration increased to 1.172 (95% CI: 1.010-1.361; p = 0.036), compared with participants without refractory pain.

CONCLUSION

This study is the first to show the diagnostic value of serum VEC and Vcn for AAD and their relationships with the clinical characteristics of patients with TBAD. Thus, VEC and Vcn are potential serum markers of TBAD.

Analysis of Inflammation-Related Genes in Patients with Stanford Type A Aortic Dissection

Background: Aortic dissection (AD) is a life-threatening cardiovascular disease. Pathophysiologically, it has been shown that aortic wall inflammation promotes the occurrence and development of aortic dissection. Thus, the aim of the current research was to determine the inflammation-related biomarkers in AD. Methods: In this study, we conducted differentially expressed genes (DEGs) analysis using the GSE153434 dataset containing 10 type A aortic dissection (TAAD) and 10 normal samples downloaded from the Gene Expression Omnibus (GEO) database. The intersection of DEGs and inflammation-related genes was identified as differential expressed inflammation-related genes (DEIRGs). Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed for DEIRGs. We then constructed the protein-protein interaction (PPI) network using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database and identified hub genes using the Cytoscape plugin MCODE. Finally, least absolute shrinkage and selection operator (LASSO) logistic regression was used to construct a diagnostic model. Results: A total of 1728 DEGs were identified between the TAAD and normal samples. Thereafter, 61 DEIRGs are obtained by taking the intersection of DEGs and inflammation-related genes. The GO indicated that DEIRGs were mainly enriched in response to lipopolysaccharide, in response to molecules of bacterial origin, secretory granule membrane, external side of plasma, receptor ligand activity, and signaling receptor activator activity. KEGG analysis indicated that DEIRGs were mainly enriched in cytokine-cytokine receptor interaction, TNF signaling pathway, and proteoglycans in cancer. We identified MYC, SELL, HIF1A, EDN1, SERPINE1, CCL20, IL1R1, NOD2, TLR2, CD69, PLAUR, MMP14, and HBEGF as hub genes using the MCODE plug-in. The ROC indicated these genes had a good diagnostic performance for TAAD. Conclusion: In conclusion, our study identified 13 hub genes in the TAAD. This study will be of significance for the future development of a preventive therapy of TAAD.

Pre-Test Probability Assessment and d-Dimer Based Evaluation in Patients with Previous Acute Aortic Syndrome

Background and Objectives. Acute aortic syndromes (AASs) are emergencies burdened by high morbidity and mortality. Guideline-recommended diagnostic workup is based on pre-test probability assessment (PPA) and d-dimer testing. However, the performance of PPA and d-dimer has never been studied in individuals with previous AAS (pAAS), which represent a challenging population. Materials and Methods. We analyzed a registry of patients with pAAS evaluated in two Emergency Departments (EDs) for suspected novel AAS (nAAS). Enrolment criteria were history of pAAS and the presence of truncal pain, syncope or perfusion deficit. All patients underwent advanced imaging. Clinical data were registered prospectively and PPA was performed by applying the aortic dissection detection (ADD) and an aorta simplified (AORTAs) score. Results. A total of 128 patients were enrolled, including 77 patients with previous Stanford type A aortic dissection and 45 patients with previous Stanford type B aortic dissection. The final diagnosis was nAAS in 40 (31%) patients. Clinical variables associated with nAAS were: aortic valve disease, thoracic aortic aneurysm, severe pain, sudden pain, ripping/tearing pain and hypotension/shock. ADD score ≥ 2 had a sensitivity of 65% and a specificity of 83% for nAAS; AORTAs score ≥ 2 had a sensitivity of 48% and a specificity of 88%. d-dimer (cutoff ≥ 500 ng/mL or age-adjusted cutoff) had a sensitivity of 97% and a specificity of 13%/14.7%, for diagnosis of nAAS. Patients that were candidates for guideline-compliant PPA/d-dimer integrated rule-out were: 5 (4.9%) with ADD ≤ 1/d-dimer and 8 (7.8%) with AORTAs ≤ 1/d-dimer < age-adjusted cutoff. None of them had a nAAS. Conclusions. Patients with pAAS evaluated in the ED for red-flag symptoms showed intermediate-to-high pre-test probability of nAAS. The ADD score had lower sensitivity and specificity than in unselected patients. d-dimer, alone and integrated with PPA, was highly sensitive for nAAS, but very unspecific. PPA/d-dimer integrated strategies are unlikely to significantly reduce the number of patients with pAAS undergoing advanced imaging.

The role of peripheral blood eosinophil counts in acute Stanford type A aortic dissection patients

Background

Acute Stanford-A aortic dissection (AAAD) is a devastating cardiovascular condition with high mortality, therefore identifying risk prognosis factors is vital for the risk stratification of patients with AAAD. Here, we investigated peripheral blood eosinophil (EOS) counts in patients with AAAD and their possible biological implications.

Methods

We performed a single center retrospective cohort study. From 2011 to 2021, a total of 1,190 patients underwent AAAD surgery. Patients were categorized first by death and then admission EOS counts (0.00 × 109/L or &gt;0.00 × 109/L). Demographics, laboratory data, and outcomes were analyzed using standard statistical analyses. Ascending aorta specimens were used for western blotting and histological assessments.

Results

Death group patients had lower EOS counts than the non-death group (P = 0.008). When patients were stratified using mean blood EOS counts: 681 patients had low (0.00 × 109/L) and 499 had high (&gt;0.00 × 109/L) counts. Patients with low EOS counts at admission were more likely to have a higher mortality risk (P = 0.017) and longer treatment in the intensive care unit (ICU) days (P = 0.033) than patients with normal EOS counts. Also, the five blood coagulation items between both groups showed significantly different (P &lt; 0.001). Hematoxylin &amp; eosin-stained cross-sections of the ascending aorta false lumen showed that EOSs were readily observed in thrombi in the false lumen of the aorta.

Conclusions

Peripheral blood EOS counts may be involved in thrombosis and could be an effective and efficient indicator for the diagnosis, evaluation, and prognosis monitoring of patients with AAAD.

The diagnostic and prognostic value of D-dimer in different types of aortic dissection

Objective

To evaluate the serum D-dimer level and its diagnostic and prognostic predictive value in patients with different types of aortic dissection.

Methods

Eighty-four aortic dissection patients who were diagnosed clinically in our hospital from January 2017 to January 2021 were selected for the study. All patients were divided into Stanford type A (39 cases) and Stanford type B (45 cases) groups. The serum D-dimer level was detected at 1 h, 6 h, 12 h, 24 h, and 72 h after admission to the hospital, and its expression level with different types of aortic dissection was analyzed. The relationship between D-dimer and the prognosis of patients was also analyzed.

Results

The serum D-dimer levels of patients in group A were significantly higher than those in group B at 6 h, 12 h, 24 h, and 72 h after admission, and the differences were statistically significant. In group A, 16 patients died, and 23 patients survived, while in group B, 18 patients died, and 27 patients survived. The serum D-dimer level of the dead and surviving patients in group A was significantly higher than that of group B, and the serum D-dimer level of dead patients in groups A and B was significantly higher than that of surviving patients. For diagnostic value, the AUC was 0.89, sensitivity was 76.92%, specificity was 90.00% in group A, and the AUC was 0.82, sensitivity was 71.11%, and specificity was 85.00% in group B. For the prognostic predicted value, the AUC was 0.74 in group A, while the AUC was 0.69 in group B.

Conclusions

D-dimer has different serum levels in different types of aortic dissection patients, with higher levels in Stanford A. Serum D-dimer levels may be used as a better biomarker to diagnose the two types of aortic dissection and play an important role in patient prognostic prediction, especially Stanford type A.

Tracking an Elusive Killer: State of the Art of Molecular-Genetic Knowledge and Laboratory Role in Diagnosis and Risk Stratification of Thoracic Aortic Aneurysm and Dissection

The main challenge in diagnosing and managing thoracic aortic aneurysm and dissection (TAA/D) is represented by the early detection of a disease that is both deadly and “elusive”, as it generally grows asymptomatically prior to rupture, leading to death in the majority of cases. Gender differences exist in aortic dissection in terms of incidence and treatment options. Efforts have been made to identify biomarkers that may help in early diagnosis and in detecting those patients at a higher risk of developing life-threatening complications. As soon as the hereditability of the TAA/D was demonstrated, several genetic factors were found to be associated with both the syndromic and non-syndromic forms of the disease, and they currently play a role in patient diagnosis/prognosis and management-guidance purposes. Likewise, circulating biomarker could represent a valuable resource in assisting the diagnosis, and several studies have attempted to identify specific molecules that may help with risk stratification outside the emergency department. Even if promising, those data lack specificity/sensitivity, and, in most cases, they need more testing before entering the “clinical arena”. This review summarizes the state of the art of the laboratory in TAA/D diagnostics, with particular reference to the current and future role of molecular-genetic testing.

Impacts of eosinophil percentage on prognosis acute type A aortic dissection patients

Background

Eosinophils are pro-inflammatory cells involved in thrombosis and have been proposed as a prognosis marker in acute ischemic stroke and ST-elevation myocardial Infarction. Here, we sought to clarify the prognostic value of eosinophil percentage (EOS%) in patients with acute type A aortic dissection (AAAD).

Methods

We examined 183 consecutive AAAD patients. Based on the optimum cut-off value of EOS% determined by X-tile software, patients were classified into the low EOS% (EOS% ≤ 0.1) and high EOS% groups (EOS% > 0.1). We performed multivariate regression analysis and Kaplan–Meier (KM) survival curves to assess the association between EOS% and mortality. Eosinophil accumulation in aortic dissection intraluminal thrombus was confirmed using hematoxylin–eosin (H&E) staining. An external cohort from Medical Information Mart for Intensive Care IV was performed to validate the results.

Results

Relative to surviving patients, those who died during hospitalization had significantly lower EOS% (p = 0.001) but significantly higher WBC (p = 0.002) and neutrophil (p = 0.001) counts. Multivariate regression analysis identified EOS% as an independent predictor of in-hospital and 1-year mortality. KM curves revealed that 1-year cumulative mortality was significantly higher in the low EOS% group, although it was mainly attributed to the higher 30-day mortality. H&E staining revealed massive infiltration of eosinophils in all 20 thrombus specimens. The external validation confirmed that relative to survivors, patients with in-hospital mortality (p = 0.010) had significantly lower EOS%. Moreover, multivariate regression analyses identified that decreased EOS% was independently significantly associated with in-hospital mortality.

Conclusions

Low EOS% is significantly related to increased mortality rates in AAAD patients.

Dysregulation of interaction between LOXhigh fibroblast and smooth muscle cells contributes to the pathogenesis of aortic dissection

Rationale: While cell-cell interaction plays a critical role in physiology and disease, a comprehensive understanding of its dynamics in vascular homeostasis and diseases is yet absent. Methods: Here, by use of single-cell RNA-sequencing and multi-color staining, we delineate the cellular composition and spatial characterization of human aorta with or without aortic dissection (AD). Results: Scrutinization of cell subtype alterations revealed significantly changed fibroblast (FB)-smooth muscle cell (SMC) interactions in AD. Of these cellular interactions, LOX^high fibroblast (fibroblast subtype 2, FB2) in diseased state exerted the most pronounced effects on pathological deterioration of SMCs in AD. In addition, pharmacologically targeting the BMP (bone morphogenetic protein) signaling pathway effectively suppressed FB2 state transition and reduced AD incidence in mice. Finally, COL5A1 (collagen type V alpha 1 chain), one of the secreted proteins released from FB2, was significantly higher in the plasma of AD patients than in control patients, suggesting its potential use as a biomarker for AD diagnosis. Conclusions: Our work not only identified a pivotal role of a specific FB subtype in AD progression, but also shed light on cell interaction dynamics in vascular diseases.

Association of Etoricoxib treatment and incident hypoxia in patients with aortic dissection undergoing endovascular aortic repair

OBJECTIVE

The current study was to evaluate the association of Etoricoxib treatment and incident hypoxia among type-B aortic dissection (AD) patients undergoing endovascular aortic repair (EVAR).

METHODS

Patients undergoing EVAR were retrospectively recruited. Based on Etoricoxib use, patients were divided into the non-treated and Etoricoxib-treated groups. Baseline characteristics including demographics, laboratory parameters, characteristics of aortic computer tomography and echocardiography, medications used, and procedural characteristics were collected from the electronic health record.

RESULTS

Compared to non-treated group (n = 36), prevalence of obesity and fever at baseline was higher in Etoricoxib-treated group (n = 24; P < 0.05). Mean number of neutrophils, and mean serum CRP and D-dimer levels were higher in Etoricoxib-treated group (P < 0.05). The overall incidence of hypoxia was lower in Etoricoxib-treated group (44.4% vs 33.4%, P < 0.05). Increase in neutrophils count, serum CRP and D-dimer levels was associated with incident hypoxia, with an odds ratio (OR) of 1.36 (95% confidence interval [CI] 1.07-1.65), 1.44 (95% CI 1.12-1.78) and 1.25 (95% CI 1.01-1.47) respectively. In unadjusted model, Etoricoxib use was associated with a 44% lower odds of incident hypoxia. After adjustment for inflammatory markers, the association between Etoricoxib and incident hypoxia was non-significant, with OR of 0.95% and 95% CI of 0.78-1.06.

CONCLUSION

Compared to patients who did not receive Etoricoxib during hospitalization, those treated with Etoricoxib had lower incidence of hypoxia, which might be attributed to its anti-inflammatory effects.

Diagnostic performances of neutrophil to lymphocyte ratio and lymphocyte to monocyte ratio in acute ischemic stroke caused by cervicocranial arterial dissection

BACKGROUND

Inflammation plays an important role in the initiation and progression of cervicocranial arterial dissection (CCAD). New inflammatory indices derived from full cell blood count may be associated with increased risk of acute ischemic stroke (AIS) caused by CCAD. The goal of this study is to evaluate the diagnostic performances of neutrophil to lymphocyte ratio (NLR) and lymphocyte to monocyte ratio (LMR) in CCAD.

METHOD

We retrospectively analyzed 52 patients with AIS caused by CCAD from emergency room (group I), 51 patients with CCAD from emergency room or clinic(group II) and 52 controls (group III), age and sex matched. Data were collected on the admission including NLR and LMR.

RESULTS

Neutrophil to lymphocyte ratio and LMR have significant differences among three groups, especially in group I vs both groups II and III (P < .001). There was a negative correlation between admission NLR and LMR. Low LMR level and high NLR level may be associated with severity of AIS caused by CCAD and significantly predict AIS in CCAD. The area under the curve of NLR and LMR were 0.77 and 0.71, respectively, on receiver operating characteristic curve analysis. The optimal cutoff values of NLR and LMR that best discriminated AIS were 2.35 (81% sensitivity and 63% specificity) and 3.67 (64% sensitivity and 77% specificity).

CONCLUSIONS

Neutrophil to lymphocyte ratio neutrophil to lymphocyte ratio and LMR may contribute to the diagnostic evaluation and prompt immediate therapy in patients with CCAD.

Non-coding RNAs in aortic dissection: From biomarkers to therapeutic targets

Aortic dissection (AD) is the rupture of the aortic intima, causing the blood in the cavity to enter the middle of the arterial wall. Without urgent and proper treatment, the mortality rate increases to 50% within 48 hours. Most patients present with acute onset of symptoms, including sudden severe pain and complex and variable clinical manifestations, which can be easily misdiagnosed. Despite this, the molecular mechanisms underlying AD are still unknown. Recently, non‐coding RNAs have emerged as novel regulators of gene expression. Previous studies have proven that ncRNAs can regulate several cardiovascular diseases; therefore, their potential as clinical biomarkers and novel therapeutic targets for AD has aroused widespread interest. To date, several studies have reported that microRNAs are crucially involved in AD progression. Additionally, several long non‐coding RNAs and circular RNAs have been found to be differentially expressed in AD samples, suggesting their potential roles in vascular physiology and disease. In this review, we discuss the functions of ncRNAs in AD pathophysiology and highlight their potential as biomarkers and therapeutic targets for AD. Meanwhile, we present the animal models previously used for AD research, as well as the specific methods for constructing mouse or rat AD models.

Identification of Serum Biomarker in Acute Aortic Dissection by Global and Targeted Metabolomics

BACKGROUND

Acute aortic dissection (AAD) is the most devastating aortic pathology, and the incidence is increasing worldwide. However, the occurrence and development of AAD are unpredictable. A thorough understanding of the serum metabolic landscape through metabolomic analysis may help identify new biomarkers for AAD and offers new insights into its prevention and evaluation.

METHODS

Nineteen patients with Stanford type A aortic dissection and 20 healthy individuals were enrolled in this study. We use global and targeted mass spectrometry-based metabolomics to investigate the serum metabolomics profiles, and the data were analyzed by principal component analysis and orthogonal partial least squares discriminant analysis.

RESULTS

Initial untargeted metabolomics analysis revealed significant changes of lipids and polar metabolites in patients with AAD. Alterations of the phosphatidylcholine metabolic pathway were further observed by targeted metabolomics. Trimethylamine N-oxide (TMAO) levels were obviously increased in patients with AAD compared with controls (P < 0.005), whereas the levels of carnitine (P < 0.005), choline, and betaine (P < 0.05) were decreased. Furthermore, TMAO levels were associated with disease severity in AAD and correlated positively with C-reactive protein levels (r = 0.537, P = 0.018), IL-6 levels (r = 0.546, P = 0.016), D-dimer levels (r = 0.694, P = 0.001), and maximum aortic diameter on admission (r = 0.748, P = 0.002).

CONCLUSIONS

Patients with AAD showed a predominant and consistent change of metabolites levels, especially the compounds in the phosphatidylcholine metabolic pathway. TMAO could potentially serve as a biomarker for the auxiliary diagnosis and evaluation of AAD.

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.

Prospective diagnostic accuracy study of plasma soluble ST2 for diagnosis of acute aortic syndromes

Acute aortic syndromes (AASs) are difficult to diagnose emergencies. Plasma soluble ST2 (sST2), a prognostic biomarker for heart failure, has been proposed as a diagnostic biomarker of AASs outperforming D-dimer, the current diagnostic standard. We performed a prospective diagnostic accuracy study of sST2 for AASs in the Emergency Department (ED). In 2017–2018, patients were enrolled if they had ≥1 red-flag symptoms (chest/abdominal/back pain, syncope, perfusion deficit) and a clinical suspicion of AAS. sST2 was detected with the Presage® assay. Adjudication was based on computed tomography angiography (CTA) or on diagnostic outcome inclusive of 30-day follow-up. 297 patients were enrolled, including 88 with AASs. The median age was 67 years. In 162 patients with CTA, the median sST2 level was 41.7 ng/mL (IQR 29.4–103.2) in AASs and 34.6 ng/mL (IQR 21.4–51.5) in alternative diagnoses (P = 0.005). In ROC analysis, the AUC of sST2 was 0.63, as compared to 0.82 of D-dimer (P < 0.001). Sensitivity and specificity values of sST2 associated with different cutoffs were: 95.5% and 10.8% (≥12 ng/mL), 84.1% and 29.7% (≥23.7 ng/mL), 35.2% and 85.1% (≥66.5 ng/mL). Results were similar in the full cohort. In conclusion, in patients from a European ED, plasma sST2 provided modest accuracy for diagnosis of AASs.

Prognostic Role of Admission C-Reactive Protein Level as a Predictor of In-Hospital Mortality in Type-A Acute Aortic Dissection: A Meta-Analysis

BACKGROUND

Acute aortic dissection (AD) is a lethal vascular disease, accounting for over 90% cases of acute aortic syndrome. Despite advances in understanding associated risk factors, the long-term prognosis for AD patients is still poor. Several prognostic biomarkers have been used for AD as per the IRAD, such as older age (>70 years), onset of chest pain and hypotension, but they are not effective in all patients. Instead, C-reactive protein (CRP) is a consistent inflammatory marker. CRP levels are abnormally increased in AD. However, the prognostic value of serum CRP level in AD remains unclear.

OBJECTIVE

To perform a systematic review and meta-analysis (registration no CRD42017056205) to evaluate whether CRP is a biomarker associated with in-hospital mortality in type-A AD.

METHODS

PubMed, Web of Science, CNKI, SciELO, and EMBASE were searched for papers published from January 2000 to October 2017 for studies on the prognostic role of CRP at admission in type-A AD patients. Outcome data were extracted and pooled hazard ratios (HRs) were calculated.

RESULTS

18 (N = 2875 patients) studies met the inclusion criteria. Elevated CRP level was associated with a significantly increased risk of in-hospital mortality in patients with type-A AD (HR = 1.15, 95% CI: 1.06-1.25, p = 0.001). The pooled sensitivity of CRP in type-A AD patients was 77% (95% CI 69%-84%, p < 0.001), and the specificity was 72% (95% CI 66%-78%, p < 0.001).

CONCLUSION

Elevated CRP level is significantly associated with increased risks of in-hospital mortality in patients with type-A AD. CRP is a convenient prognostic factor in type-A AD patients.

Eye Surface Temperature as a Potential Indicator of Physical Fitness in Ranch Horses

This study aimed to investigate the use of maximum eye surface temperature (EST_max), recorded by infrared thermography, as an indicator of physical fitness in ranch horses. Data collection was carried out with 16 horses by recording six physical fitness biomarkers (EST_max, respiratory rate, creatine kinase activity [CK], and concentrations of total serum protein, plasmatic cortisol, and lactate) before and after a regular working day. We also recorded heart rate during the exercise, exercise duration, average velocity, distance traveled, and air temperature and humidity. The variation between the sampling times was compared by using repeated measures ANOVA or Wilcoxon paired test. The t-test was used to compare EST_max means of dehydrated and nondehydrated horses. The differences (DIF-) between each variable's sampling times were calculated, and the Spearman's correlation coefficients between DIF-EST_max and DIF- of other variables were estimated. A hierarchical cluster analysis was used to classify the horses according to their physical fitness. All biomarkers increased after the workday, and the EST_max means of dehydrated and nondehydrated horses did not differ (P < .05). DIF-CK and DIF-EST_max were positively correlated (rs = 0.56, P < .05). The cluster analysis defined two groups of horses (LOW and HIGH), with DIF-EST_max and DIF-CK differing statistically between them. HIGH horses showed CK higher than 350 U/L, indicating some degree of muscle damage. These results suggest that EST_max has potential to predict changes in CK and, thus could be a useful indicator of physical fitness in ranch horses; although, its effectiveness has to be confirmed in future studies.

Serum levels of matrix metalloproteinase 9 and toll-like receptor 4 in acute aortic dissection: a case-control study

Background

Matrix metalloproteinase 9 (MMP9) and Toll-like receptor 4 (TLR4) play important roles in aortic pathophysiology. However, there is lacking research on serum TLR4 levels in acute aortic dissection (AAD) patients, and the performance of serum MMP9 and TLR4 for the diagnosis of AAD is still unknown. This study aimed to evaluate the serum levels of MMP9 and TLR4 in AAD patients, identify their associations with circulating C-reactive protein (CRP) and D-dimer, which are well-known classical biomarkers of AAD, and further explore the potential diagnostic role of MMP9 and TLR4 in AAD.

Methods

Serum levels of MMP9 and TLR4 were measured by enzyme-linked immunosorbent assay (ELISA) in 88 AAD patients and 88 controls. The clinical test related information was collected from patients’ electronic medical records.

Results

Serum MMP9 and TLR4 levels were significantly higher in AAD patients than those in healthy controls in the general and stratified comparisons. Either serum MMP9 or TLR4 was independently associated with the risk of AAD (all p < 0.001). There was a positive significant association between serum MMP9 and TLR4 (r = 0.518, p < 0.001). Both MMP9 and TLR4 levels were statistically correlated with circulating CRP, but not D-dimer. Based on receiver-operating characteristic (ROC) analysis, the area under the curves (AUCs) of MMP9 and TLR4 alone for the diagnosis of AAD were 0.810 and 0.799 with optimal cut-off points of 379.47 ng/ml and 7.83 ng/ml, respectively. Moreover, a combination of serum MMP9 and TLR4 increased the AUC to 0.89 with a sensitivity of 60.2% and specificity of 94.3%.

Conclusions

Serum MMP9 and TLR4 could be potential biomarkers for identifying AAD, while the combined diagnostic value was higher in safely ruling out AAD.

Prospective diagnostic and prognostic study of copeptin in suspected acute aortic syndromes

Acute aortic syndromes (AAS) are cardiovascular emergencies with unmet diagnostic needs. Copeptin is released upon stress conditions and is approved for rule-out of myocardial infarction (MI). As MI and AAS share presenting symptoms, stress mechanisms and necessity for rapid diagnosis, copeptin appears as an attractive biomarker also for AAS. We thus performed a diagnostic and observational study in Emergency Department (ED) outpatients. Inclusion criteria were chest/abdominal/back pain, syncope and/or perfusion deficit, plus AAS in differential diagnosis. Blood samples were obtained in the ED. 313 patients were analyzed and 105 (33.5%) were diagnosed with AAS. Median copeptin was 38.91 pmol/L (interquartile range, IQR, 16.33-173.4) in AAS and 7.51 pmol/L (IQR 3.58-15.08) in alternative diagnoses (P < 0.001). Copeptin (≥10 pmol/L) had a sensitivity of 80.8% (95% confidence interval, CI, 72.2-87.2) and a specificity of 63.6% (CI 56.9-69.9) for AAS. Within 6 hours, the sensitivity and specificity were 88.7% (CI 79.3-94.2) and 52.4% (CI 42.9-61.8) respectively. Combination with D-dimer did not increase the diagnostic yield. Furthermore, copeptin ≥25 pmol/L predicted mortality in patients with alternative diagnoses but not with AAS. In conclusion, copeptin increases in most patients with AAS within the first hours, but the accuracy of copeptin for diagnosis AAS is suboptimal.

Intense exercise and endurance-training program influence serum kinetics of muscle and cardiac biomarkers in dogs

Few data exist on the physiological consequences of an incremental exercise test (IET) and training in dogs. Here we evaluated the effect of an endurance-training program (ETP) on the kinetics of the serum biomarkers: creatine kinase (CK), aspartate aminotransferase (AST), myoglobin, cardiac troponin I (cTnI), and creatine kinase isoenzyme MB (CK-MB). Eighteen Beagle dogs were assigned to three groups: sedentary (S), untrained (U), and trained (T). The dogs from the groups T and U underwent IET, and their lactate threshold (LT) was determined. The LT and velocity corresponding to the LT (VLT) was determined by visual inspection. The VLT was utilized to determine the training intensity level. Thus, the dogs from group T underwent an eight-week aerobic conditioning program with the intensity training set to 70-80% of the VLT. Next, dogs from the groups T and U have submitted to IET again. The group S did not undergo IETs or training. The maximal velocity (Vmax) at which the dog achieves in the IET and heart rate were determined. For biomarkers, venous blood samples were collected before the experimental procedure (baseline) and before and 1, 6, 12, 24, 48, and 72 h after the IETs. VLT and Vmax increased in group T (P < .05), indicating an improvement in dogs' aerobic and anaerobic fitness. CK and AST rose (P < .05), peaking 6 h after both IETs and returning to baseline levels after 12-24 h. Levels of cTnI and myoglobin were unaltered. CK-MB peaked 1 h after the IETs and returned to baseline levels after 12 h (P < .05). We concluded that ETP improved the aerobic capacity of the dogs without any skeletal or cardiac muscle injury.

Post-Transcriptional Control of Tropoelastin in Aortic Smooth Muscle Cells Affects Aortic Dissection Onset

Aortic dissection (AD) is a catastrophic disease with high mortality and morbidity, characterized with fragmentation of elastin and loss of smooth muscle cells. Although AD has been largely attributable to polymorphisms defect in the elastin-coding gene, tropoelastin (TE), other undermined factors also appear to play roles in AD onset. Here, we investigated the effects of post-transcriptional control of TE by microRNAs (miRNAs) on elastin levels in aortic smooth muscle cells (ASMC). We found that miR-144-3p is a miRNA that targets TE mRNA in both human and mouse. Bioinformatics analyses and dual luciferase reporter assay showed that miR-144-3p inhibited protein translation of TE, through binding to the 3'-UTR of the TE mRNA. Interestingly, higher miR-144-3p levels and lower TE were detected in the ASMC obtained from AD patients, compared to those from non-AD controls. In a mouse model for human AD, infusion of adeno-associated viruses (serotype 6) carrying antisense for miR-144-3p (as-miR-144-3p) under CAG promoter significantly reduced the incidence and severity of AD, seemingly through enhancement of TE levels in ASMC. Thus, our data suggest an essential role of miR-144-3p on the pathogenesis of AD.

White blood cell and platelet count as adjuncts to standard clinical evaluation for risk assessment in patients at low probability of acute aortic syndrome

AIMS

Pre-test probability assessment is key in the approach to suspected acute aortic syndromes (AASs). However, most patients with AAS-compatible symptoms are classified at low probability, warranting further evaluation for decision on aortic imaging. White blood cell count, platelet count and fibrinogen explore pathophysiological pathways mobilized in AASs and are routinely assayed in the workup of AASs. However, the diagnostic performance of these variables for AASs, alone and as a bundle, is unknown. We tested the hypothesis that white blood cell count, platelet count and/or fibrinogen at presentation may be applied as additional tools to standard clinical evaluation for pre-test risk assessment in patients at low probability of AAS.

METHODS AND RESULTS

This was a retrospective observational study conducted on consecutive patients managed in our Emergency Department from 2009 to 2014 for suspected AAS. White blood cell count, platelet count and fibrinogen were assayed during evaluation in the Emergency Department. The final diagnosis was obtained by computed tomography angiography. The pre-test probability of AAS was defined according to guidelines. Of 1210 patients with suspected AAS, 1006 (83.1%) were classified at low probability, and 271 (22.4%) were diagnosed with AAS. Within patients at low probability, presence of at least one alteration among white blood cell count >9*10³/µl, platelet count <200*10³/µl and fibrinogen <350 mg/dl was associated with a sensitivity of 95.5% (89.7-98.5%) and a specificity of 18.3% (15.6-21.2%). In patients at low probability, white blood cell count >9*10³/µl and platelet count <200*10³/µl were found as independent predictors of AAS beyond established clinical risk markers. Within patients at low probability, the estimated risk of AAS based on the number of alterations amongst white blood cell count >9*10³/µl and platelet count <200*10³/µl was 2.7% (1.2-5.7%) with zero alterations, 11.3% (8.8-14.3%) with one alteration and 31.9% (24.8-40%) with two alterations ( p<0.001).

CONCLUSION

In addition to standard clinical evaluation, white blood cell count and platelet count may be used in patients at low pre-test probability to fine-tune risk assessment of AAS.