A decrease in integrin α5ß1/FAK is associated with increased apoptosis of aortic smooth muscle cells in acute type a aortic dissection.

BACKGROUND: Acute type A aortic dissection (AAAD) is a devastating disease. Human aortic smooth muscle cells (HASMCs) exhibit decreased proliferation and increased apoptosis, and integrin α5ß1 and FAK are important proangiogenic factors involved in regulating angiogenesis. The aim of this study was to investigate the role of integrin α5ß1 and FAK in patients with AAAD and the potential underlying mechanisms. METHODS: Aortic tissue samples were obtained from 8 patients with AAAD and 4 organ donors at Zhongshan Hospital of Fudan University. The level of apoptosis in the aortic tissues was assessed by immunohistochemical (IHC) staining and terminal-deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) assays. The expression of integrin α5ß1 and FAK was determined. Integrin α5ß1 was found to be significantly expressed in HASMCs, and its interaction with FAK was assessed via coimmunoprecipitation (Co-IP) analysis. Proliferation and apoptosis were assessed by Cell Counting Kit-8 (CCK-8) assays and flow cytometry after integrin α5ß1 deficiency. RESULTS: The levels of integrin α5ß1 and FAK were both significantly decreased in patients with AAAD. Downregulating the expression of integrin α5ß1-FAK strongly increased apoptosis and decreased proliferation in HASMCs, indicating that integrin α5ß1-FAK might play an important role in the development of AAAD. CONCLUSIONS: Downregulation of integrin α5ß1-FAK is associated with increased apoptosis and decreased proliferation in aortic smooth muscle cells and may be a potential therapeutic strategy for AAAD.

Derivation of a HEAR Pathway for Emergency Department Chest Pain Patients to Safely Avoid a Second Troponin Test.

The study aims to develop a decision pathway based on HEAR score and 0 h high-sensitivity cardiac troponin T (hs-cTnT) to safely avoid a second troponin test for suspected non-ST elevation myocardial infarction (NSTEMI) in emergency departments. A HEAR score consists of history, electrocardiogram, age, and risk factors. A HEAR pathway is established using a Bayesian approach based on a predefined safety threshold of NSTEMI prevalence in the rule-out group. In total, 7131 patients were retrospectively enrolled, 582 (8.2%) with index visit NSTEMI and 940 (13.2%) with 180-day major adverse cardiovascular events (MACE). For patients with a low-risk HEAR score (0 to 2) and low 0 h hs-cTnT (<14 ng/L), the HEAR pathway recommends early discharge without further testing. After the HEAR pathway had been applied to rule out NSTEMI, the negative predictive value of index visit NSTEMI was 100.0% (95% CI, 99.8% to 100.0%) and false-negative rate of 180-day MACE was 0.40% (95% CI, 0.18% to 0.87%). Compared with the 0 h hs-cTnT < limit of detection (LoD) strategy (<5 ng/L), the HEAR pathway could correctly reclassify 1298 patients without MACE as low risk and lead to a 18.2% decrease (95% CI, 17.4-19.1%) in the need for a second troponin test. The HEAR pathway may lead to a substantial and safe reduction in repeated troponin test for emergency department patients with suspected NSTEMI.

Simple Death Risk Models to Predict In-hospital Outcomes in Acute Aortic Dissection in Emergency Department.

Objective: We sought to find a bedside prognosis prediction model based on clinical and image parameters to determine the in-hospital outcomes of acute aortic dissection (AAD) in the emergency department. Methods: Patients who presented with AAD from January 2010 to December 2019 were retrospectively recruited in our derivation cohort. Then we prospectively collected patients with AAD from January 2020 to December 2021 as the validation cohort. We collected the demographics, medical history, treatment options, and in-hospital outcomes. All enrolled patients underwent computed tomography angiography. The image data were systematically reviewed for anatomic criteria in a retrospective fashion by three professional radiologists. A series of radiological parameters, including the extent of dissection, the site of the intimal tear, entry tear diameter, aortic diameter at each level, maximum false lumen diameter, and presence of pericardial effusion were collected. Results: Of the 449 patients in the derivation cohort, 345 (76.8%) were male, the mean age was 61 years, and 298 (66.4%) had a history of hypertension. Surgical repair was performed in 327 (72.8%) cases in the derivation cohort, and the overall crude in-hospital mortality of AAD was 10.9%. Multivariate logistic regression analysis showed that predictors of in-hospital mortality in AAD included age, Marfan syndrome, type A aortic dissection, surgical repair, and maximum false lumen diameter. A final prognostic model incorporating these five predictors showed good calibration and discrimination in the derivation and validation cohorts. As for type A aortic dissection, 3-level type A aortic dissection clinical prognosis score (3ADPS) including 5 clinical and image variables scored from -2 to 5 was established: (1) moderate risk of death if 3ADPS is <0; (2) high risk of death if 3ADPS is 1-2; (3) very high risk of death if 3ADPS is more than 3. The area under the receiver operator characteristic curves in the validation cohorts was 0.833 (95% CI, 0.700-0.967). Conclusion: Age, Marfan syndrome, type A aortic dissection, surgical repair, and maximum false lumen diameter can significantly affect the in-hospital outcomes of AAD. And 3ADPS contributes to the prediction of in-hospital prognosis of type A aortic dissection rapidly and effectively. As multivariable risk prediction tools, the risk models were readily available for emergency doctors to predict in-hospital mortality of patients with AAD in extreme clinical risk.