Prediction for future occurrence of type A aortic dissection using computational fluid dynamics.

Background:Acute type A aortic dissection (ATAAD) and acute type A intramural hematoma (ATAIMH) are life-threatening diseases with high mortality. To better understand their clinical features in the Chinese population, we analyzed the data from the first Registry of Aortic Dissection in China (Sino-RAD) to promote the understanding and management of the diseases.Methods:All patients with ATAAD and ATAIMH enrolled in Sino-RAD from January 1, 2012 to December 31, 2016 were involved. The data of patients’ selection, history, symptoms, management, outcomes, and postoperation complications were analyzed in the study. The continuous variables were compared using the Student's t test for normal distributions and the Mann-Whitney U test for non-normal distributions. Categorical variables were compared using the Chi-square test or Fisher exact test.Results:A total of 1582 patients with ATAAD and 130 patients with ATAIMH were included. The mean age of all patients was 48.4 years. Patients with ATAAD were significantly younger than patients with ATAIMH (48.9 years vs. 55.6 years, P < 0.001). For the total cohort, males were dominant, but the male ratio of patients with ATAAD was significantly higher compared to those with ATAIMH (P = 0.01). The time range from the onset of symptom to hospitalization was 2.0 days. More patients of ATAIMH had hypertension than that of ATAAD (82.3% vs. 67.6%, P < 0.05). Chest and back pain were the most common clinical symptoms. Computerized tomography (CT) was the most common initial diagnostic imaging modality. 84.7% received surgical treatment and in-hospital mortality was 5.3%. Patients with ATAAD mainly received surgical treatment (89.6%), while most patients with ATAIMH received medical treatment (39.2%) or endovascular repair (35.4%).Conclusions:Our study suggests that doctors should comprehensively use clinical examination and genetic background screening for patients with ATAAD and ATAIMH and further shorten the time range from symptoms onset to intervention, achieving early diagnosis and treatment, thereby reducing the mortality rate of patients with aortic dissection in China. We should standardize the procedures of aortic dissection treatment and improve people's understanding. Meanwhile, the curing and transferring efficiency should also be improved.

Background: Fractional flow reserve (FFR) is used to evaluate the need for percutaneous coronary intervention (PCI) in cases of moderate stenosis of the coronary artery. Recently, diagnostic imaging support with computational fluid dynamics (CFD) analysis has been garnering attention. This study defines the relationship between FFR conducted for cardiac catheterization and CFD analyses conducted using coronary computed tomography (CT) for moderate stenosis, in addition to considering whether wall pressure (WP) and wall shear stress (WSS) can be used to evaluate ischemia.Methods and Results: Cases in which FFR was measured via coronary CT and cardiac catheterization was performed within 3 months were collected retrospectively. In the CFD analysis, WP and WSS were calculated and compared with FFR. Three groups were created to compare results of CFD analysis and FFR values according to the location of the stenosis: the right coronary artery, the left anterior descending artery, and the left circumflex artery. There was a correlation between FFR and WSS according to CFD analysis for moderate stenosis of the coronary artery, with a cut-off value for treatment able to be calculated.Conclusions: The results of this study suggest that ischemia can be evaluated by conducting CFD analysis (WSS) using coronary CT.

Background:Coagulation disorders are potentially one of the most important pathogeneses of acute respiratory distress syndrome (ARDS) following acute type A aortic dissection (ATAAD). This study aimed to determine whether aortic dissection singularly and cardiopulmonary bypass (CPB) surgery can activate coagulation pathways, promoting ARDS development in patients with ATAAD.Methods:A total of 450 patients who received treatment at Beijing Anzhen Hospital, Capital Medical University, between March 2023 and February 2024 were consecutively enrolled in this prospective cohort study. We analyzed the clinical factors and measured serum coagulation biomarkers by enzyme-linked immunosorbent assay (ELISA) among patients with ATAAD, aortic aneurysm (AA), or unstable angina (UA). Logistic regression, two-way analysis of variance (ANOVA), and Spearman's correlation analysis were performed. Furthermore, the patients with ATAAD were divided into ARDS (based on chest radiographic findings and an oxygenation index ≤300 mmHg) and non-ARDS groups for subgroup comparisons.Results:The incidence of postoperative ARDS among patients with ATAAD was 20.7% (13.3% in the AA group and 7.3% in the UA group). Preoperatively, prothrombin time (PT) was longer in patients with ATAAD than in those with AA or UA ((odds ratio (OR): 12.0, 95% confidence interval (CI): 11.5–12.6) vs. (OR: 11.4, 95% CI: 10.9–12.1) vs. (OR: 11.2, 95% CI: 10.8–11.6), respectively; p < 0.001). The D-dimer levels, fibrin degradation products (FDPs), factor XIIa, and factor VIII-Ag (FVIII-Ag) were significantly elevated preoperatively and postoperatively in patients with ATAAD. The FDP levels in the ATAAD subgroup immediately after surgery were significantly higher in the ARDS group compared with those in the non-ARDS group (OR: 2.26, 95% CI: 1.13–4.54; p = 0.022). In addition, a negative correlation existed between the FXII level (correlation coefficient r = –0.682, p = 0.043) at 24 hours after surgery and the oxygenation index.Conclusion:Coagulation activation may be caused by aortic dissection singularly and CPB, which promotes postoperative ARDS in patients with ATAAD.

ObjectiveThe main aim of this study is to measure and calculate the ratio of sinotubular junction diameter to body surface area (RDA) in patients with acute type A aortic dissection (ATAAD) and normal subjects, and to analyze the relationship between RDA and ATAAD to provide guidance for primary prevention of ATAAD.MethodsThis retrospective observational study totally admitted consecutive 320 patients with acute type A aortic dissection diagnosed in Nanjing First Hospital from March 2017 to March 2021. Meanwhile, 608 healthy subjects who took echocardiography examination in outpatient was selected as controls. The diameter of sinotubular junction (D.STJ) was measured using echocardiography and direct vision (in some ATAAD patients). The differences in body surface area (BSA), D.STJ and RDA index in both groups were assessed. The association between D.STJ and demographic characteristics were established. RDA index was used to distinguish the ATAAD and healthy subjects.ResultsThe diameter of STJ (24.41 ± 2.16 mm versus 26.66 ± 2.60 mm) and RDA index (13.16 ± 1.67 versus 15.40 ± 1.59) were significantly different between dissection group and control group. The D.STJ were found a positive, linear correlation to BSA in the healthy subjects. Multivariate logistic regression showed that RDA index was one of the independent risk factors to associated with ATAAD as a continuous variable (odds ratio (OR), 0.403, 95% confidence interval (CI): 0.352–0.457, P < 0.001) or a categorical variable (RDA cut-off: 13.88 mm/m2, OR, 0.070, 95%CI: 0.050–0.098, P < 0.001).ConclusionsRDA index is an independent and key risk factor for ATAAD occurrence. Timely identification of high-risk patients using RDA index has the potential to become an optional guidance for primary prevention of ATAAD.

Malperfusion is a devastating complication afflicting 16–33% of acute type A aortic dissection (AAAD) [1]. It may result in myocardial, cerebral, spinal, extremity, renal and visceral ischaemia and is most common in extensive DeBakey type I dissection [2, 3]. In this issue of the Journal, Pacini et al. [4] report a cohort of 502 AAAD, of which 103 (20.5%) had a malperfusion syndrome (MPS). The presence of malperfusion increased hospital mortality three-fold and multivariable analysis identified mesenteric or cardiac malperfusion and shock (present in 39% of MPS cases) as independent predictors of early mortality. The Emilio-Romagna region of Italy has a population of 4.4 million and is served by six surgical cardiac centres [5]. If all diagnosed AAADs undergo surgery, the annual incidence of (operated) AAAD is 13 pmp and is comparable with the Swedish experience [6]; the real denominator is those reaching hospital alive and diagnosed AAAD but treated medically [16% as in International Registry of Acute Aortic Dissection (IRAD)]. The definition of malperfusion is important as was noted in the study. For MPS to occur, the patients in this Registry were required to have ‘signs and symptoms due to altered blood flow with clinical evidence of a lack of blood flow resulting in ischaemia with organ dysfunction’. While demonstration of radiological malperfusion may also be important, it is the ischaemic consequences of malperfusion and end organ dysfunction that compromise survival [7]. Thus, although a patient may have CT evidence of reduced true luminal innominate artery flow, the prognostic relevance of this is primarily determined by the presence of neurological ischaemia. The low preoperative brain malperfusion rate (7.8%) in this series may explain the lower postoperative stroke risk (8.8%) in 44 patients (9 with preoperative malperfusion) than in either the IRAD or the German Registry for Acute Aortic Dissection Type A (GERAADA) registries [8]. Within GERAADA, preoperative neurological deficit occurred in 20.3% of all patients prior to surgery, 12.6% of which resolved postoperatively and 7.7% persisted. New neurological deficit after AAAD surgery occurred in 9.5% of patients. In agreement with GERAADA, stroke was more common in any anatomical MPS. Approximately 30% of cases were undertaken without deep hypothermic circulatory arrest (DHCA), 16% with DHCA and 53% with antegrade selective cerebral perfusion (15% with axillary artery cannulation). No differences in the outcome were noted between these perfusion strategies. Similarly, GERAADA reported no differences in the outcome between cerebral protection strategies [9]. The victims of acute aortic dissection have poor long-term survival, in the reported series, of 65% at 5 years. This was lower in the MPS patients, but remained at 70% for non-MPS patients. The causes of these deaths have not been reported but need to be examined carefully if the attrition rate is to be attenuated. However, it was probably not due to dissection-related aneurysmal disease as actuarial freedom from reoperation was 96.6% at 5 years in a 100% follow-up study. This provides food for thought for those advocating a more aggressive approach in primary type A dissection repair. Thus, in keeping with other recent reports, the Emilia-Romagna Registry has given us more questions than answers. We can certainly say that malperfusion increases perioperative mortality and decreases long-term survival, but are we any closer to finding better ways of managing it?

Perioperative blood transfusions and postoperative drainage volume not only are the commonly recognized risk factors for acute kidney injury (AKI) but also are indirect indicators of coagulopathy in patients with acute type A aortic dissection (ATAAD). However, standard laboratory tests fail to accurately reflect and assess the overall coagulopathy profile in patients with ATAAD. Thus, this study aimed to explore the association between the hemostatic system and severe postoperative AKI (stage 3) in patients with ATAAD using thromboelastography (TEG). We selected 106 consecutive patients with ATAAD who underwent emergency aortic surgery at Beijing Anzhen Hospital. All participants were categorized into the stage 3 and non-stage 3 groups. The hemostatic system was evaluated using routine laboratory tests and TEG preoperatively. We undertook univariate and multivariate stepwise logistic regression analyses to determine the potential risk factors for severe postoperative AKI (stage 3), with a special investigation on the association between hemostatic system biomarkers and severe postoperative AKI (stage 3). The receiver operating characteristic (ROC) curves were generated to assess the predictive ability of hemostatic system biomarkers for severe postoperative AKI (stage 3). A total of 25 (23.6%) patients developed severe postoperative AKI (stage 3), including 21 patients (19.8%) who required continuous renal replacement therapy (RRT). Multivariate logistic regression analysis demonstrated that the preoperative fibrinogen level (OR, 2.02; 95% CI, 1.03 to 3.00; p = 0.04), platelet function (MA level) (OR, 1.23; 95% CI, 1.09 to 1.39; p = 0.001), and cardiopulmonary bypass (CPB) time (OR, 1.01; 95% CI, 1.00 to 1.02; p = 0.02) were independently associated with severe postoperative AKI (stage 3). The cutoff values of preoperative fibrinogen and platelet function (MA level) for predicting severe postoperative AKI (stage 3) were determined to be 2.56 g/L and 60.7 mm in the ROC curve [area under the curve (AUC): 0.824 and 0.829; p < 0.001]. The preoperative fibrinogen level and platelet function (measured by the MA level) were identified as potential predictive factors for developing severe postoperative AKI (stage 3) in patients with ATAAD. Thromboelastography could be considered a potentially valuable tool for real-time monitoring and rapid assessment of the hemostatic system to improve postoperative outcomes in patients.

Determinants of Operative Mortality in Patients With Ruptured Acute Type A Aortic Dissection

Introduction: Acute type A Aortic dissection (ATAAD) may require urgent surgical repair, and a major complication is acute ischemic stroke (AIS) post-surgery. Aim: To explore characteristics associated with AIS in ATAAD patients post-surgical repair (PSR). Hypothesis: We assessed the hypothesis that multiple factors influence events of AIS in ATAAD patients PSR. Method: Multivariate regression analysis for factors influencing AIS in adults with a principal diagnosis of ATAAD and undergoing surgical repair was performed via the 2016-2020 National Inpatient Sample. Results: Among the 20335 ATAAD cases with surgical repair, 14.7%(2985 cases) reported an event of AIS. Individuals ≥60 years (vs. ages 18-39 years, aOR 1.323, p=0.007) and presence of hypertension (aOR 1.228, P&lt;.001), acute kidney injury (AKI) (aOR 1.353, P&lt;.001), Charlson Comorbidity Index (CCI) ≥3 (aOR 15.129, p&lt;.001), and Private insurances (vs. Medicare, aOR 1.454, p&lt;.001) or Medicaid (vs. Medicare, aOR 1.673, p&lt;.001) showed higher odds of developing AIS. On the contrary, smoking (aOR 0.613, p&lt;.001), obesity (aOR 0.882, p=0.027), cirrhosis (aOR 0.309, p&lt;.001), dyslipidemia (aOR 0.732, p&lt;.001), diabetes (DM) (aOR 0.508, p&lt;.001), peripheral vascular disease (PVD) (aOR 0.615, p&lt;.001), Chronic Kidney Disease (CKD) (aOR 0.446, p&lt;.001), prior MI (aOR 0.461, p&lt;.001) and prior stroke (aOR 0.788, p=0.04) and Black race (aOR 0.736, p&lt;.001) indicated lower odds. No significant difference was seen in age 40-59 (aOR 1.06, p=0.545), drug abuse (aOR 1.093, p=0.451), alcohol abuse (aOR 0.925, p=0.476), Females (vs. Males, aOR 0.973, p=0.579), and Hispanics (vs. Whites, aOR 1.102, p=0.285). Conclusion: In conclusion, a 14.7% rate of AIS in ATAAD PSR was observed. Ages ≥60, hypertension, AKI, CCI ≥3, and Private and Medicaid insurance holders appeared prone to AIS following such events, while smoking, obesity, cirrhosis, dyslipidemia, DM, PVD, CKD, prior MI, prior stroke, and Blacks had reduced odds.

Atherosclerosis involves an inflammatory response due to plaque formation within the arteries, which can lead to ischemic stroke and heart disease. It is one of the leading causes of death worldwide, with various contributing factors such as hyperlipidemia, hypertension, obesity, diabetes, and smoking. Wall shear stress (WSS) is also known as a contributing factor of the formation of atherosclerotic plaques. Since the causes of atherosclerosis cannot be attributed to a single factor, clearly understanding the mechanisms and causes of its occurrence is crucial for preventing the disease and developing effective treatment strategies. To better understand atherosclerosis and define the correlation between various contributing factors, computational fluid dynamics (CFD) analysis is primarily used. CFD simulates WSS, the frictional force caused by blood flow on the vessel wall with various hemodynamic changes. Using apolipoprotein E knockout (ApoE-KO) mice subjected to partial ligation and a high-fat diet at 1-week, 2-week, and 4-week intervals as an atherosclerosis model, CFD analysis was conducted along with the reconstruction of carotid artery blood flow via magnetic resonance imaging (MRI) and compared to the inflammatory factors and pathological staining. In this experiment, a comparative analysis of the effects of high WSS and low WSS was conducted by comparing the standard deviation of time-averaged wall shear stress (TAWSS) at each point within the vessel wall. As a novel approach, the standard deviation of TAWSS within the vessel was analyzed with the staining results and pathological features. Since the onset of atherosclerosis cannot be explained by a single factor, the aim was to find the correlation between the thickness of atherosclerotic plaques and inflammatory factors through standard deviation analysis. As a result, the gap between low WSS and high WSS widened as the interval between weeks in the atherosclerosis mouse model increased. This finding not only linked the occurrence of atherosclerosis to WSS differences but also provided a connection to the causes of vulnerable plaques.

Acute type A aortic dissection (ATAAD) remains one of the most time-critical cardiovascular emergencies, with early mortality continuing to pose substantial clinical and organizational challenges. Large-scale observational registries offer valuable insights into real-world outcomes across healthcare systems. To synthesize and compare early mortality rates in patients with ATAAD as reported by national and multicentre registries. A structured search was conducted in PubMed, Google Scholar and the Cochrane Library for studies published within the last 10 years. We included registry-based studies reporting in-hospital, 30-day, operative or 48-hour mortality following ATAAD. Study characteristics, demographic profiles and preoperative risk factors were extracted. A total of 20 studies, comprising 77,267 patients, were included. In-hospital mortality was reported in 13 registries (n = 50,470), with rates ranging from 5% to 29%. Thirty-day mortality was reported in 5 registries (n = 19,521) and operative mortality in 2 registries (n = 14,825). Substantial variation in outcome definitions and case inclusion criteria limited direct comparability. Early mortality in ATAAD remains high and heterogeneous across registries. Strengthening global registry participation and adopting standardized reporting practices are essential steps toward improving risk stratification, guiding clinical decisions, and advancing equitable care in ATAAD.

Aortic dissection is characterized by the redirection of blood flow, which flows through an intimal tear into the aortic media. The purpose of this study was to find potential acute type A aortic dissection (AAAD)-related genes and molecular mechanisms by bioinformatics. The gene expression profiles of GSE52093 were obtained from Gene Expression Omnibus (GEO) database, including 7 AAAD samples and 5 normal samples. The differentially expressed genes (DEGs) were detected between AAAD and normal samples. The functional annotation and pathway enrichment analysis were conducted through the Database for Annotation, Visualization and Integration Discovery (DAVID). A protein-protein interaction network was established by the Search Tool for the Retrieval of Interacting Genes (STRING) software. The microRNAs (miRNAs) of these differentially expressed genes were predicted using <microRNA.org> database. Moreover, DEGs were analyzed in the comparative toxicogenomics (CTD) database to screen out the potential therapeutic small molecules. As a result, there were 172 DEGs identified in patients with AAAD. These DEGs were significantly enriched in 6 pathways, including cell cycle, oocyte meiosis, DNA replication, extracellular matrix-receptor interaction, and mineral absorption pathway. Notably, CDC20, CDK1, CHEK1, KIF20A, MCM10, PBK, PTTG1, RACGAP, and TOP2A were crucial genes with a high degree in the protein-protein interaction network. Furthermore, potential miRNAs (miR-301, miR-302 family, and miR-130 family) were identified. In addition, small molecules like azathioprine and zoledronic acid were identified to be potential drugs for AAAD.

Introduction: We examined the viability of pairing wire-obtained flow pressure data with computational fluid dynamic (CFD) analysis for accurate patient-specific 3D reconstruction of flow through cerebral vessels—an approach that provides comprehensive velocity data and other flow parameters to assist the preventative diagnosis of cerebral stenosis. Methods: Two physical phantom models of a cerebral stenosis—differing in regard to vascular morphology at and around the stenosis—were prepared, filled with physiological saline and connected individually to a flow pump (Vascular Simulations LLC Left Heart Replicator) applying pulsatile flow. Pressure measurements were taken upstream of the stenosis by microcatheter-guided wires to define an inlet boundary condition for CFD analysis. Pressure and velocity at 2 cm proximal to stenosis, the stenosis inlet, the stenosis outlet, and 2 cm distal to stenosis were measured to validate the CFD simulated flow. Results: Excellent agreement was observed between CFD and wire-measured time-dependent flow pressure, with the expected pulsatile behavior observed at each location. Between the two methods, differences in maximum systolic pressures ranged between |0.73±0.72|% and |3.90±0.74|%. Differences in minimum diastolic pressures ranged between |1.79±1.33|% and |9.08±1.42|%. Velocity data from wire measurements lacked pulsatile behavior and showed differences ranging between |2.93±5.20|% and |120.10±2.91|% from CFD-obtained measurements, which did show correct pulsatile behavior. Larger discrepancies were strongly associated with areas of higher CFD predicted velocities (r=0.86). Conclusion: Guidewire flow measurements provided CFD analysis with accurate inlet boundary conditions and validated CFD simulation results. CFD analysis allowed for detailed visualization of key flow parameters that may be difficult to physically measure—such as velocity—that are relevant for understanding risk factors associated with cerebral stenosis on a case-by-case basis.

Early mortality and morbidity after surgical treatment for acute type A aortic dissection (AAAD) has remained high over the last decades despite technical improvements and is still in the range of 10–30% [1–6]. The most important risk factor for this still high early mortality is the preoperative status of the patients [4, 7]. Especially end-organ malperfusion contributes significantly to perioperative death and is present in approximately one-third of all patients with acute aortic dissection [3, 7–9]. Coronary, cerebral, visceral and lower extremity malperfusion syndromes are most often associated with type A dissection. A significant surgical dilemma is the treatment of AAAD patients with preoperative cerebral malperfusion [7]. Intimal tears in the proximal aorta often up to 37% [10] result in the involvement of the supra-aortic branches. Consequently, the impaired flow in the brainsupplying arteries is, besides coronary arteries, the most frequent form of malperfusion [7]. The reported incidence of neurological deficit before surgery in AAAD varies between 14% [7] and 20% [11]. The general surgical strategy in AAAD patients is directed towards (i) cannulation and perfusion of the true lumen, (ii) perfusion of all body regions intraoperatively, (iii) a certain degree of hypothermia, (iv) avoiding aortic cross-clamp during distal repair (open distal anastomosis), (v) avoiding changing arterial cannulation site and uncertain de-airing manoeuvres when resuming total body perfusion after distal aortic repair and (vi) unrestricted global perfusion postoperatively. To develop an individual surgical plan for those patients with supra-aortic malperfusion, preoperative assessment of the extent of dissection and type of malperfusion is of utmost importance. This assessment is usually done with computed tomography angiography (CTA) preoperatively, which translates to only a few minutes of delay on the way to the operating theatre and is just as important for the surgical outcome as surgical experience [6, 12]. Malperfusion can be further validated intraoperatively by using transoesophageal echocardiography (TEE), orbital Doppler and near-infrared spectroscopy (NIRS) [9]. One has to keep in mind, however, that NIRS does not provide information in the basilar artery region [9]. There is an ongoing debate about the best surgical strategy for AAAD in general and even more for the high-risk subgroup of patients with cerebral malperfusion [9]. Despite a consensus that the true lumen of the arterial system should be cannulated [13], the approaches vary considerably. This lack of evidence to enable any recommendations for the choice of surgical methods is related to the fact that randomized studies in AAAD (with wide variations of pathologies) are very unlikely to be performed. Even though a meta-analysis of 14 papers between axillary artery and femoral artery perfusion has shown that axillary arterial perfusion had a significantly lower complication rate [14], routes that are currently advocated for AAAD include subclavian (right and left) cannulation, common carotid artery (right and left) cannulation [15, 16], cannulation of the innominate artery, peripheral cannulation of a non-dissected artery (femoral), ascending aortic cannulation (Fig. 1) [17] or apex of the left ventricle (transapical). There is also no agreement about optimal protection (e.g. temperature) during circulatory arrest; however, even the best method of protection would be useless if the cerebral perfusion and other end-organ perfusion have not been restored during cardiopulmonary bypass (CPB) and aortic repair. In this ‘Great Debate’, different approaches are being described and the rationale for doing so is explained by world-known experts in this field. Special emphasis will be placed on common carotid, subclavian and innominate artery cannulation for antegrade cerebral perfusion (ACP). The rationale of retrograde cerebral perfusion (RCP) during selective cerebral perfusion is also described.

D-dimer has been proven to be an excellent rule-out marker for acute type A aortic dissection (ATAAD) with a sensitivity exceeding 95% while specificity remains low. We hypothesized that the addition of fibrinogen, which is decreased in ATAAD patients due to consumption coagulopathy, would increase predictive ability. This was an exploratory, retrospective, single-region, observational study comparing ATAAD patients with available preoperative D-dimer and fibrinogen values who underwent surgery at our department between 2008 and 2023 (93 patients) to all patients who visited an emergency department (ED) in a region of southern Sweden during 2017 and 2018 and whose D-dimer and fibrinogen values were obtained within 24 h (202 patients). The discriminative capacity of ATAAD was evaluated by comparing the area under the curve (AUC) from receiver operating characteristics (ROC) curves calculated for each biomarker alone and for the D-dimer/fibrinogen ratio. The AUC for the ability of D-dimer and fibrinogen to discriminate ATAAD from other diagnoses was 0.784 (95% CI 0.733–0.836) and 0.756 (95% CI 0.701–0.811), respectively. The AUC for the D-dimer/fibrinogen ratio was 0.812 (95% CI 0.764–0.860). In this exploratory study, we could show that the D-dimer/fibrinogen ratio increased the ability to predict ATAAD compared to the biomarkers alone. The improvement in discriminative ability was small, however, and needs further validation to be clinically useful.

Preoperative coronary angiography and outcomes in acute type A aortic dissection with coronary malperfusion: A retrospective cohort study.