Acute aortic dissection

SP2509 functions as a novel ferroptosis inhibitor by reducing intracellular iron level in vascular smooth muscle cells

Previous studies have shown that ferroptosis of vascular smooth muscle cells (VSMCs) is involved in the development of aortic dissection (AD) and that histone methylation regulates this process. SP2509 acts as a specific inhibitor of lysine-specific demethylase 1 (LSD1), which governs a variety of biological processes. However, the effect of SP2509 on VSMC ferroptosis and AD remains to be elucidated. This aim of this study was to investigate the role and underlying mechanism of SP2509-mediated histone methylation on VSMC ferroptosis. Here, a mouse model of AD was established, and significantly reduced levels of H3K4me1 and H3K4me2 (target of SP2509) were found in the aortas of AD mice. In VSMCs, SP2509 treatment led to a dose-dependent increase in H3K4me2 levels. Furthermore, we found that SP2509 provided equivalent protection to ferrostatin-1 against VSMC ferroptosis, as evidenced by increased cell viability, decreased cell death and lipid peroxidation. RNA-sequencing analysis and subsequent experiments revealed that SP2509 counteracted cystine deficiency-induced response to inflammation and oxidative stress. More importantly, we demonstrated that SP2509 inhibited the expression of TFR and ferritin to reduce intracellular iron levels, thereby effectively blocking the process of ferroptosis. Therefore, our findings indicate that SP2509 protects VSMCs from multiple stimulus-induced ferroptosis by reducing intracellular iron levels, thereby preventing lipid peroxidation and cell death. These findings suggest that SP2509 may be a promising drug to alleviate AD by reducing iron deposition and VSMC ferroptosis.

Admission Left-Arm Systolic Blood Pressure and In-Hospital Mortality After Acute Type A Aortic Dissection Repair

AIM

Admission systolic blood pressure is a significant predictor of in-hospital mortality in patients with acute type A aortic dissection (ATAAD). While previous studies have focussed on recording the highest blood pressure value from both arms, this study aimed to evaluate the associations between blood pressure in bilateral arms and in-hospital mortality.

METHODS

Data were analysed from 262 patients with ATAAD treated at a single centre. The relationship between bilateral arm blood pressure upon admission and in-hospital mortality was assessed in a logistic regression model. To comprehensively evaluate potential non-linear relationships, the association between admission bilateral systolic blood pressure (SBP) and the risk of in-hospital mortality was analysed using restricted cubic splines on a continuous scale.

RESULTS

Mean age was 53.6±12.5 years and 194 (74.0%) were male. Baseline and operative data showed that ages, body mass index, smoking, left-arm SBP, left-arm diastolic blood pressure (DBP), right-arm SBP, right-arm DBP, syncope, cerebral/cardiac ischaemia, retrograde brain perfusion, Bentall procedure, coronary artery bypass grafting, and aortic valve replacement significantly differed among the left-arm SBP tertiles. In-hospital mortality was 17.6% (46 of 262). Restricted cubic splines demonstrated that the relationship between presenting left-arm SBP and in-hospital mortality followed a U-shaped curve, whereas non-linearity was not detected in the right arm.

CONCLUSION

This study found a U-shaped association between admission left-arm SBP and in-hospital mortality in ATAAD surgery patients, whereas a non-linearity relationship was not detected for right-arm SBP. Low left-arm SBP independently correlated with increased in-hospital mortality, underscoring the significance of bilateral blood pressure differences in ATAAD prognosis.

Elucidating thoracic aortic dissection pathogenesis: The interplay of m1A-related gene expressions and miR-16-5p/YTHDC1 Axis in NLRP3-dependent pyroptosis

The underlying molecular mechanisms of thoracic aortic dissection (TAD) remain incompletely understood. Recent insights into RNA methylation and microRNA-mediated gene regulation offer new avenues for exploring how these processes contribute to the pathophysiology of TAD, particularly through the modulation of pyroptosis and smooth muscle cell viability. This research aimed to elucidate the interplay of m1A-related gene expressions and miR-16-5p/YTHDC1 Axis in NLRP3-dependent pyroptosis, a mechanism implicated in the pathogenesis of TAD. We collected tissue samples from 28 human TAD patients and 8 healthy aortic group, as well as utilized a mouse model to replicate the disease. A combination of computational, in vitro, and in vivo methods was applied, including CIBERSORTx analysis, Pearson correlation, gene transfection using antagomiR-16-5p, siRNA, and several staining as well as cell culture techniques. Our analysis indicated two differentially expressed genes, ALKBH2 and YTHDC1. We found significant upregulation of has-miR-16-5p and downregulation of YTHDC1 at mRNA level in AD samples. Immune cell infiltration in TAD samples was examined using the CIBERSORTx database. We confirmed that YTHDC1 was a target of miR-16-5p, as evidenced by an inhibitory effect on luciferase activity. Inhibition of miR-16-5p enhanced SMC proliferation and promoted cell viability whilst downregulating NLRP3-pyroptosis. YTHDC1 expression was increased, and NLRP3-pyroptosis expressions were inhibited, suggesting miR-16-5p/YTHDC1 axis may involve the NLRP3-pyroptosis of the SMC. In vivo analyses confirmed the prevention of NLRP3-pyroptosis in middle layer of the thoracic aorta, implying that the miR-16-5p/YTHDC1 axis regulated SMC proliferation via NLRP3-pyroptosis signaling. Our findings underscored the anti-pyroptotic role of miR-16-5p/YTHDC1 axis in the pathogenesis of TAD, suggesting a potential therapeutic strategy via targeting YTHDC1 and suppressing miR-16-5p to inhibit NLRP3-dependent pyroptosis. Although further investigation is needed, these results relating to SMC proliferation are a significant step forward in understanding TAD.

Aortic mineralization triggers the risk of acute type B aortic dissection

BACKGROUND AND AIMS

The role of aortic mineralization in the pathogenesis of acute type B aortic dissection (TBAD) is unclear. Whether thoracic aortic calcification (TAC) and circulating alkaline phosphatase (ALP) activity are associated with acute TBAD risk remains elusive.

METHODS

Observational and Mendelian randomization (MR) studies were conducted sequentially. Using propensity score matching (1:1) by age and sex, patients with acute TBAD (n = 125) were compared with control patients (n = 125). Qualitative (score) and quantitative (volume) analyses of the TAC burden on different thoracic aortic segments were conducted using non-enhanced computed tomography. Univariate and multivariate analyses were used to identify significant independent risk factors for TBAD and TAC burden, respectively. MR was finally used to determine the causal relationship between elevated ALP activity and TBAD risk.

RESULTS

The qualitative and quantitative analyses revealed that TAC burden was significantly higher in the TBAD group, except for in the ascending aortic segment (both p < 0.05). Preoperative circulating ALP was significantly elevated in the TBAD group (p < 0.001). The elevated TAC burden score on the descending thoracic aortic segment (odds ratio [OR] 3.31, 95% confidence interval [CI] 1.31-8.37) and increased ALP activity (OR 1.03, 95% CI 1.01-1.06) was independently associated with TBAD risk. Interestingly, ALP was significantly positively associated with TAC burden, and MR analyses confirmed that ALP genetically predicted TBAD risk.

CONCLUSIONS

Elevated ALP may trigger TBAD risk via the increased volume of TAC. Aortic mineralization may not protect the aorta itself.

Dietary vitamin C and vitamin E with the risk of aortic aneurysm and dissection: A prospective population-based cohort study

BACKGROUND AND AIMS

The associations between dietary vitamin C (VC), vitamin E (VE) intake and aortic aneurysm and dissection (AAD) remain unclear. This study aimed to prospectively investigate the associations between dietary VC and VE with the incident risk of AAD.

METHODS AND RESULTS

A total of 139 477 participants of UK Biobank cohort were included in the analysis. Dietary VC and VE consumptions were acquired through a 24-h recall questionnaire. Cox proportional regression models were used to examine the associations between VC, VE intake and the risk of AAD. Incident AAD was ascertained through hospital inpatient records and death registers. During a median follow-up of 12.5 years, 962 incident AAD events were documented. Both dietary VC [adjusted hazard ratio (HR), 0.77; 95 % confidence intervals (CI), 0.63-0.93; P-trend = 0.008] and VE (adjusted HR, 0.70; 95 % CI, 0.57-0.87; P-trend = 0.002) were inversely associated with incident AAD when comparing the participants in the highest quartile with those in the lowest. In subgroup analyses, the associations were more pronounced in participants who were over 60 years old, participants with smoking history, hypertension or hyperlipidemia, who were under the high risk of AAD.

CONCLUSION

Higher dietary VC and VE intakes are associated with reduced risk of AAD. Our study emphasizes the importance of diet adjustment strategies targeted on VC and VE to lower the incidence rate of AAD especially in the high-risk population.

Prognostic implication of residual inflammatory trajectories in acute type I aortic dissection: dual-center prospective cohort study

BACKGROUND

Peripheral platelet-white blood cell ratio (PWR) integrating systemic inflammatory and coagulopathic pathways is a key residual inflammatory measurement in the management of acute DeBakey type I aortic dissection (AAD); however, trajectories of PWR in AAD is poorly defined.

METHODS

Two AAD cohorts were included in two cardiovascular centers (2020-2022) if patients underwent emergency total arch replacement with frozen elephant trunk implantation. PWR data were collected over time at baseline and five consecutive days after surgery. Trajectory patterns of PWR were determined using the latent class mixed modelling (LCMM). Cox regression was used to determine independent risk factors. By adding PWR Trajectory, a user-friendly nomogram was developed for predicting mortality after surgery.

RESULTS

Two hundred forty-six patients with AAD were included with a median follow-up of 26 (IRQ 20-37) months. Three trajectories of PWR were identified [cluster α 45(18.3%), β105 (42.7%), and γ 96 (39.0%)]. Cluster γ was associated with higher risk of mortality at follow-up (crude HR, 3.763; 95% CI: 1.126-12.574; P =0.031) than cluster α. By the addition of PWR trajectories, an inflammatory nomogram, composed of age, hemoglobin, estimated glomerular filtration rate, and cardiopulmonary time was developed and internally validated, with adequate discrimination [the area under the receiver-operating characteristic curve 0.765, 95% CI: 0.660-0.869)], calibration, and clinical utility.

CONCLUSION

Based on PWR trajectories, three distinct clusters were identified with short-term outcomes, and longitudinal residual inflammatory shed some light to individualize treatment strategies for AAD.

Uncovering Druggable Targets in Aortic Dissection: An Association Study Integrating Mendelian Randomization, pQTL, and Protein-Protein Interaction Network

Aortic dissection (AD) is a life-threatening acute aortic syndrome. There are limitations and challenges in the discovery and application of biomarkers and drug targets for AD. Mendelian randomization (MR) analysis is a reliable analytical method to identify effective therapeutic targets. We aimed to identify novel therapeutic targets for AD and investigate their potential side-effects based on MR analysis. Data from protein quantitative trait loci (pQTLs) were used for MR analyses to identify potential therapeutic targets. We probed druggable proteins involved in the pathogenesis of aortic dissection from deCODE. In this study, a two-sample MR analysis was conducted, with druggable proteins as the exposure factor and data on genome-wide association studies (GWAS) of AD as the outcome. After conducting a two-sample MR, summary data-based Mendelian randomization (SMR) analysis and colocalization analysis were performed. A protein-protein interaction (PPI) network was also constructed to delve into the interactions between identified proteins. After MR analysis and the Steiger test, we identified five proteins as potential therapeutic targets for AD. SMR analysis and colocalization analysis also confirmed our findings. Finally, we identified ASPN (OR = 1.36, 95% CI: 1.20, 1.54, p = 4.22 × 10-5) and SPOCK2 (OR = 0.57, 95% CI: 0.41, 0.78, p = 4.52 × 10-4) as the core therapeutic targets. Through PPI network analysis, we identified six druggable targets, enabling the subsequent identification of six promising drugs from DrugBank for treating AD. This discovery of specific proteins as novel therapeutic targets represents a significant advancement in AD treatment. These findings provide more effective treatment options for AD.

Investigation of the Association between Bilateral Selective Anterograde Cerebral Perfusion and Postoperative Ischemic Stroke in Obese Patients with Emergency Surgery for Acute Type A Aortic Dissection

Background and objectives: The relationship between cerebral perfusion and new postoperative ischemic stroke in obese patients is not well defined. The aim of this study was to investigate the association between selective bilateral anterograde cerebral perfusion and new postoperative ischemic stroke in obese patients with emergency surgery for acute type A aortic dissection. Materials and methods: A total of 292 patients with emergency surgery for acute type A aortic dissection were included in this study. Patients with hemorrhagic stroke or ischemic stroke with severe neurological dysfunction at admission that were not candidates for surgery; patients who died in the first 48 h after intensive care admission and patients with incomplete medical records were excluded. Results: The mean age was 59.42 ± 10.68 years and the mean Euroscore was 9.12 ± 1.63. Obesity was present in 76.4%, the incidence of new postoperative ischemic stroke was 27.5%, and the postoperative mortality rate was 26.7%. The mean cardiopulmonary bypass time was 206.81 ± 75.48 min, the aortic cross-clamp time was 118.2 ± 46.42 min, and 90% of cases required cerebral perfusion. The mean cerebral perfusion time was 30.8 ± 24.41 min. Obese patients had a higher frequency of in-hospital death (p = 0.009), smoking (p = 0.036), hypertension (p = 0.023), left common carotid artery dissection (p < 0.001), right common carotid artery dissection (p = 0.029), femoral artery cannulation (p = 0.026), aortic root replacement (p = 0.009), aortic valve replacement (p = 0.005) and early reintervention for bleeding (p = 0.004). Using logistic regression, selective bilateral anterograde cerebral perfusion over 40 min in obese patients was independently associated with new postoperative ischemic stroke (OR = 2.35; 95%CI = 1.36-4.86; p = 0.021). Conclusions: A patient-tailored strategy for cerebral perfusion should be considered in obese patients, considering the high atheromatous burden of the supra-aortic vessels in these patients and the potential risk of atheromatous embolization associated with this technique.

A predictive model of 30-day mortality in patients with acute type A aortic dissection

OBJECTIVE

Acute type A aortic dissection (ATAAD) is a life-threatening cardiovascular disease that requires an effective predictive model to predict and assess a patient's risk of death. Our study aimed to construct a model for predicting the risk of 30-day death in patients with ATAAD and the prediction accuracy of the German Registry of Acute Aortic Dissection Type A (GERAADA) Score and the European System for Cardiac Operative Risk Evaluation (EuroSCORE II) was verified.

MATERIALS AND METHODS

Between June 2019 and June 2023, 109 patients with ATAAD underwent surgical treatment at our hospital (35 in the death group and 74 in the survival group). The differences in image parameters between the two groups were compared. Search for independent predictors and develop models that predict 30-day mortality in patients with ATAAD. GERAADA Score and EuroSCORE II were retrospectively calculated and indicated mortality was assessed using the receiver operating characteristic (ROC) curve.

RESULTS

Logistic regression analysis showed that ascending aortic length and pericardial effusion were independent predictors of death within 30 days in patients with ATAAD. We constructed four models, GERAADA Score (Model 1), EuroSCORE II (Model 2), Model 1, ascending aorta length, and pericardial effusion (Model 3), and Model 2, ascending aorta length, and pericardial effusion (Model 4). The area under the curve (AUC = 0.832) of Model 3 was significantly different from those of Models 1 (AUC = 0.683) and 2 (AUC = 0.599), respectively (p < 0.05, DeLong test).

CONCLUSIONS

Adding ascending aorta length and pericardial effusion to the GERAADA Score can improve the predictive power of 30-day mortality in patients with ATAAD.

Air Pollutants and Mortality Risk in Patients with Aortic Dissection: Evidence from a Clinical Cohort, Single-Cell Sequencing, and Proteomics

We aimed to evaluate the association between air pollutants and mortality risk in patients with acute aortic dissection (AAD) in a longitudinal cohort and to explore the potential mechanisms of adverse prognosis induced by fine particulate matter (PM2.5). Air pollutants data, including PM2.5, PM10.0, nitrogen dioxide (NO2), carbon monoxide (CO), sulfur dioxide (SO2), and ozone (O3), were collected from official monitoring stations, and multivariable Cox regression models were applied. Single-cell sequencing and proteomics of aortic tissue were conducted to explore the potential mechanisms. In total, 1,267 patients with AAD were included. Exposure to higher concentrations of air pollutants was independently associated with an increased mortality risk. The high-PM2.5 group carried approximately 2 times increased mortality risk. There were linear associations of PM10, NO2, CO, and SO2 exposures with long-term mortality risk. Single-cell sequencing revealed an increase in mast cells in aortic tissue in the high-PM2.5 exposure group. Enrichment analysis of the differentially expressed genes identified the inflammatory response as one of the main pathways, with IL-17 and TNF signaling pathways being among the top pathways. Analysis of proteomics also identified these pathways. This study suggests that exposure to higher PM2.5, PM10, NO2, CO, and SO2 are associated with increased mortality risk in patients with AAD. PM2.5-related activation and degranulation of mast cells may be involved in this process.

The elephant's Achilles' heel: a case report of acute obstruction of frozen elephant trunk after proximal aortic dissection repair

Background

The frozen elephant trunk (FET) technique as a hybrid combining surgical and endovascular repair is an emerging concept to treat complex aortic dissection. Early experience showed technical feasibility and promising clinical outcomes. However, unsuspected complications still arise.

Case summary

A 25-year-old male presented to the emergency department with a 2-day history of chest pain. After exclusion of acute coronary syndrome, a computed tomography angiography (CTA) revealed Type A (DeBakey Type I) aortic dissection. The patient underwent median stenotomy for complete replacement of the ascending aorta, the aortic arch, and FET. Early after rewarming, the patient became unstable due to severe left ventricular dysfunction. Soon veno-arterial extracorporal membrane oxygenation (VA-ECMO) was required for circulatory support. The cause of deterioration remained unclear until repeated CTA showed acute obstruction of the FET. Invasive exploration confirmed a trans-FET gradient of 100 mmHg, successfully managed by repeated balloon inflation with resolution of both obstruction and gradient. The patient recovered completely without any sequela.

Discussion

While the mechanism of acute obstruction after FET remains subject to speculation, the rescue intervention of ballooning the obliteration on VA-ECMO was life-saving. Intraoperative ultrasound and videoscopic inspection may be instrumental before chest closure to avoid such critical events.

Cannabidiol protects against acute aortic dissection by inhibiting macrophage infiltration and PMAIP1-induced vascular smooth muscle cell apoptosis

Acute aortic dissection (AAD) progresses rapidly and is associated with high mortality; therefore, there remains an urgent need for pharmacological agents that can protect against AAD. Herein, we examined the therapeutic effects of cannabidiol (CBD) in AAD by establishing a suitable mouse model. In addition, we performed human AAD single-cell RNA sequencing and mouse AAD bulk RNA sequencing to elucidate the potential underlying mechanism of CBD. Pathological assays and in vitro studies were performed to verify the results of the bioinformatic analysis and explore the pharmacological function of CBD. In a β-aminopropionitrile (BAPN)-induced AAD mouse model, CBD reduced AAD-associated morbidity and mortality, alleviated abnormal enlargement of the ascending aorta and aortic arch, and suppressed macrophage infiltration and vascular smooth muscle cell (VSMC) apoptosis. Bioinformatic analysis revealed that the pro-apoptotic gene PMAIP1 was highly expressed in human and mouse AAD samples, and CBD could inhibit Pmaip1 expression in AAD mice. Using human aortic VSMCs (HAVSMCs) co-cultured with M1 macrophages, we revealed that CBD alleviated HAVSMCs mitochondrial-dependent apoptosis by suppressing the BAPN-induced overexpression of PMAIP1 in M1 macrophages. PMAIP1 potentially mediates HAVSMCs apoptosis by regulating Bax and Bcl2 expression. Accordingly, CBD reduced AAD-associated morbidity and mortality and mitigated the progression of AAD in a mouse model. The CBD-induced effects were potentially mediated by suppressing macrophage infiltration and PMAIP1 (primarily expressed in macrophages)-induced VSMC apoptosis. Our findings offer novel insights into M1 macrophages and HAVSMCs interaction during AAD progression, highlighting the potential of CBD as a therapeutic candidate for AAD treatment.

Double-branched stent graft and four-stage deployment in total arch repair: safety and feasibility evaluation in porcine models

OBJECTIVES

The primary objective of this research was to evaluate the safety and feasibility of an innovative double-branched stent graft system employing four-stage deployment technology for aortic arch repair in porcine models.

METHODS

The double-branched stent graft system consisted of a proximal polyester artificial blood vessel, the main and double-branched stent grafts and a delivery system. We utilized 12 healthy pigs as experimental animals (6 per group). Postimplantation, samples were collected at 90 and 180 days after the operations. Preoperative and postoperative imaging and intraoperative arterial blood gas analyses were performed. After the pigs were euthanized, the implanted product, surrounding tissue and major organs were collected for pathological analysis.

RESULTS

The technical success rate of the stent graft implants was 100% (12/12). All animals survived to the experimental end point. Perioperative assessments showed intact stent grafts, and imaging features at the end of the follow-up period revealed neither endoleak nor device migration. No major adverse cardiovascular events were observed during the postoperative follow-up period. Pathological examinations confirmed the satisfactory biocompatibility of the stent graft.

CONCLUSIONS

This innovative double-branched stent graft system with four-stage deployment technology was affirmed as a safe and feasible option for aortic arch repair in accordance with our preclinical evaluation with porcine models.

Chinese Additive Anti-inflammatory Action for Aortopathy & Arteriopathy (5A) Registry protocol: rationale, design and methodology

BACKGROUND

Acute aortic syndrome (AAS) is a life-threatening condition. Inflammation plays a key role in the pathogenesis, development and progression of AAS, and is associated with significant mortality and morbidity. Understanding the inflammatory responses and inflammation resolutions is essential for an appropriate management of AAS.

METHOD

Thirty Chinese cardiovascular centers have collaborated to create a multicenter observational registry (named Chinese Additive Anti-inflammatory Action for Aortopathy & Arteriopathy [5A] registry), with consecutive enrollment of adult patients who underwent surgery for AAS that was started on Jan 1, 2016 and will be ended on December 31, 2040. Specially, the impact of inflammation and anti-inflammatory strategies on the early and late adverse events are investigated. Primary outcomes are severe systemic inflammatory response syndrome (SIRS), multiple organ dysfunction syndrome (MODS), Sequential Organ Failure Assessment (SOFA) scores at 7 days following this current surgery. Secondary outcomes are SISR, 30-day mortality, operative mortality, hospital mortality, new-onset stroke, acute kidney injury, surgical site infection, reoperation for bleeding, blood transfusion and length of stay in the intensive care unit.

DISCUSSION

The analysis of this multicenter registry will allow our better knowledge of the prognostic importance of preoperative inflammation and different anti-inflammatory strategies in adverse events after surgery for AAS. This registry is expected to provide insights into novel different inflammatory resolutions in management of AAS beyond conventional surgical repair.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04398992 (Initial Release: 05/19/2020).

Causal association between uric acid levels and the risk of aortic aneurysm and aortic dissection: A two-sample Mendelian randomization study

BACKGROUND AND AIMS

Increasing numbers of studies have sought to uncover the relationship between serum uric acid (UA) levels and the risk of aortic aneurysm (AA) or aortic dissection (AD), but the causality of the associations has not been established yet. To assess this potential relationship, we conducted a two-sample Mendelian randomization (MR) analysis.

METHODS AND RESULTS

We performed two-sample Mendelian randomization (MR) analysis using independent genetic variants for UA levels from a published genome-wide association study (GWAS). Summary statistics for instrument-outcome associations from FinnGen database for AA and AD. Various sensitivity analyses were performed using different MR methods including random effects inverse variance weighting, fix effects inverse variance weighting, MR-Egger, weighted median/mode, and the contamination mixture method. Genetically predicted UA levels was associated with a higher AA risk (odds ratio (OR), 1.223; 95 % confidence interval (CI), 1.058-1.388; p = 0.017) in a simple size of 209,366 individuals. No association was found between uric acid levels and the risk of AD (OR,0.812; 95 % CI, 0.423-1.200; p = 0.293).

CONCLUSION

Our study suggests a significant and robust causal association between UA levels and risk of AA but did not support such a relationship between UA levels and AD risk, which might be interpreted with caution and further confirmed. These findings support a clinically relevant causal effect of serum urate levels on the risk of AA.

Improved detection of aortic dissection in non-contrast-enhanced chest CT using an attention-based deep learning model

Rationale and objectives

This study investigated the effects of implementing an attention-based deep learning model for the detection of aortic dissection (AD) using non-contrast-enhanced chest computed tomography (CT).

Materials and methods

We analysed the records of 1300 patients who underwent contrast-enhanced chest CT at 2 medical centres between January 2015 and February 2023. We considered an internal cohort of 200 patients with AD and 200 patients without AD and an external test cohort of 40 patients with AD and 40 patients without AD. The internal cohort was divided into training and test sets, and a deep learning model was trained using 9600 CT images. A convolutional block attention module (CBAM) and a traditional deep learning architecture (namely, You Only Look Once version 5 [YOLOv5]) were combined into an attention-based model (i.e., YOLOv5-CBAM). Its performance was measured against the unmodified YOLOv5 model, and the accuracy, sensitivity, and specificity of the algorithm were evaluated by two independent radiologists.

Results

The CBAM-based model outperformed the traditional deep learning model. In the external testing set, YOLOv5-CBAM achieved an area under the curve (AUC) of 0.938, accuracy of 91.5 %, sensitivity of 90.0 %, and specificity of 92.9 %, whereas the unmodified model achieved an AUC of 0.844, accuracy of 83.6 %, sensitivity of 71.2 %, and specificity of 96.0 %. The sensitivity results of the unmodified algorithms were not significantly different from those of the radiologists; however, the proposed YOLOv5-CBAM algorithm outperformed the unmodified algorithms in terms of detection.

Conclusions

Incorporating the CBAM attention mechanism into a deep learning model can significantly improve AD detection in non-contrast-enhanced chest CT. This approach may aid radiologists in the timely and accurate diagnosis of AD, which is important for improving patient outcomes.

Aortic arch branch-prioritized reconstruction for type A aortic dissection surgery

Background

Acute Stanford type A aortic dissection (STAAD) is a fatal condition requiring urgent surgical intervention. Owing to the complexity of the surgical process, various complications, such as neurological disorders, are common. In this study, we prioritized the reconstruction of aortic arch branches during surgery and investigated the association between prioritizing the branches and the postoperative outcomes of patients with STAAD.

Methods

Ninety-seven patients were included in the observational study and underwent total arch replacement and frozen elephant trunk technique between January 2018 and June 2021. Of these, 35 patients underwent the branch-priority technique, and 62 patients underwent the classic technique. By analyzing the perioperative outcomes, we compared the differences between the two techniques.

Results

The branch priority group had significantly shorter cardiopulmonary bypass and ventilator times and earlier postoperative wake-up times than the classic group. Additionally, the ICU stay time was shorter, with a significant decrease in neurological complications and 24 h drainage in the branch priority group compared to the classic group.

Conclusion

The branch priority technique can effectively provide better brain protection, resulting in earlier awakening of patients after surgery, reduced neurological complications, shorter ventilation time and decreased ICU hospitalization time. Therefore, it is recommended for use in aortic dissection surgeries.

Research progress in the management of vascular disease with cannabidiol: a review

The morbidity and mortality rates associated with vascular disease (VD) have been gradually increasing. Currently, the most common treatment for VD is surgery, with the progress in drug therapy remaining slow. Cannabidiol (CBD) is a natural extract of Cannabis sativa L. with sedative, analgesic, and nonaddictive properties. CBD binds to 56 cardiovascular-related receptors and exerts extensive regulatory effects on the cardiovascular system, making it a potential pharmacological agent for the management of VD. However, most CBD studies have focused on neurological and cardiac diseases, and research on the management of VD with CBD is still rare. In this review, we summarize the currently available data on CBD in the management of VD, addressing four aspects: the major molecular targets of CBD in VD management, pharmacokinetic properties, therapeutic effects of CBD on common VDs, and side effects. The findings indicate that CBD has anti-anxiety, anti-oxidation, and anti-inflammatory properties and can inhibit abnormal proliferation and apoptosis of vascular smooth muscle and endothelial cells; these effects suggest CBD as a therapeutic agent for atherosclerosis, stress-induced hypertension, diabetes-related vasculopathy, ischemia-reperfusion injury, and vascular damage caused by smoking and alcohol abuse. This study provides a theoretical basis for further research on CBD in the management of VD.

Branched-chain amino acid catabolic defect in vascular smooth muscle cells drives thoracic aortic dissection via mTOR hyperactivation

Metabolic reprogramming of vascular smooth muscle cell (VSMC) plays a critical role in the pathogenesis of thoracic aortic dissection (TAD). Previous researches have mainly focused on dysregulation of fatty acid or glucose metabolism, while the impact of amino acids catabolic disorder in VSMCs during the development of TAD remains elusive. Here, we identified branched-chain amino acid (BCAA) catabolic defect as a metabolic hallmark of TAD. The bioinformatics analysis and data from human aorta revealed impaired BCAA catabolism in TAD individuals. This was accompanied by upregulated branched-chain α-ketoacid dehydrogenase kinase (BCKDK) expression and BCKD E1 subunit alpha (BCKDHA) phosphorylation, enhanced vascular inflammation, and hyperactivation of mTOR signaling. Further in vivo experiments demonstrated that inhibition of BCKDK with BT2 (a BCKDK allosteric inhibitor) treatment dephosphorylated BCKDHA and re-activated BCAA catabolism, attenuated VSMCs phenotypic switching, alleviated aortic remodeling, mitochondrial reactive oxygen species (ROS) damage and vascular inflammation. Additionally, the beneficial actions of BT2 were validated in a TNF-α challenged murine VSMC cell line. Meanwhile, rapamycin conferred similar beneficial effects against VSMC phenotypic switching, cellular ROS damage as well as inflammatory response. However, co-treatment with MHY1485 (a classic mTOR activator) reversed the beneficial effects of BT2 by reactivating mTOR signaling. Taken together, the in vivo and in vitro evidence showed that impairment of BCAA catabolism resulted in aortic accumulation of BCAA and further caused VSMC phenotypic switching, mitochondrial ROS damage and inflammatory response via mTOR hyperactivation. BCKDK and mTOR signaling may serve as the potential drug targets for the prevention and treatment of TAD.

Postoperative thrombocytopenia and subsequent consequences in acute type A aortic dissection

OBJECTIVES

To ascertain if postoperative thrombocytopenia following open aortic surgery with a median sternotomy can predict early- and intermediate-term morbidity and mortality.

METHODS

From January 2018 to December 2022, a comparison was made between patients who had and didn't have postoperative thrombocytopenia (defined as a nadir < 75 × 103/μL after 72 h of open aortic surgery with median sternotomy). Intermediate-term mortality during follow-up was the main result, with cerebrovascular accident and acute renal injury requiring dialysis as secondary events. Inverse probability treatment weighting (IPTW) was used to account for selection bias between groups. The Kaplan-Meier method with the log-rank test was used to assess intermediate-term survivals following IPTW modification. To identify the nonlinear link between platelet nadir and mortality probability, a generalized additive mix model was applied. To help increase power in testing for the overall effect of platelet nadir on outcomes in the generalized additive mix model, the hazard ratios and 95% CIs for each subgroup and their interactions were examined.

RESULTS

The study included 457 patients, 347 male (75.9%), with mean age of 54 ± 12 years. The last follow-up was done on April 14th, 2023 and the median follow-up time was 16 (6-31) months. Following IPTW, patient characteristics were balanced among cohorts. Platelet nadir was found to be significantly inversely related to early-term mortality (IPTW-adjusted hazard ratio = 0.968 (0.960, 0.977), p < 0.001), and AKI requiring dialysis (IPTW-adjusted hazard ratio = 0.979 (0.971, 0.986), p < 0.001). A nonlinear relationship between platelet nadir and mortality risk probability during follow-up visually showed that the likelihood of mortality decreased with platelet nadir increased. In confounder-adjusted survival ('postoperative thrombocytopenia not acquired' vs 'postoperative thrombocytopenia'; HR: 0.086 [95% CI: 0.045-0.163]; p < 0.01) analysis, non-acquired postoperative thrombocytopenia was associated with a lower risk of mortality, and the treatment benefit was validated in IPTW-adjusted analysis, which showed an HR of 0.067.

CONCLUSIONS

Early postoperative thrombocytopenia following type A aortic dissection surgery is a risk factor for morbidity and mortality. Because postoperative thrombocytopenia can indicate a poor prognosis, monitoring early postoperative platelets helps identify individuals who may develop late postoperative problems, which is performed by this affordable biomarker.

H3.3B controls aortic dissection progression by regulating vascular smooth muscle cells phenotypic transition and vascular inflammation

Aortic dissection is a devastating cardiovascular disease with a high lethality. Histone variants maintain the genomic integrity and play important roles in development and diseases. However, the role of histone variants in aortic dissection has not been well identified. In the present study, H3f3b knockdown reduced the synthetic genes expression of VSMCs, while overexpressing H3f3b exacerbated the cellular immune response of VSMCs induced by inflammatory cytokines. Combined RNA-seq and ChIP-seq analyses revealed that histone variant H3.3B directly bound to the genes related to extracellular matrix, VSMC synthetic phenotype, cytokine responses and TGFβ signaling pathway, and regulated their expressions. In addition, VSMC-specific H3f3b knockin aggravated aortic dissection development in mice, while H3f3b knockout significantly reduced the incidence of aortic dissection. In term of mechanisms, H3.3B regulated Spp1 and Ccl2 genes, inducing the apoptosis of VSMCs and recruiting macrophages. This study demonstrated the vital roles of H3.3B in phenotypic transition of VSMCs, loss of media VSMCs, and vascular inflammation in aortic dissection.

Comparison of Short and Midterm Aortic Reinterventions in Acute Type A Aortic Dissection Treated by Frozen Elephant Trunk or Conventional Arch Repair

BACKGROUND

Long-term outcomes after acute type A aortic dissection (ATAAD) are related to remodelling of the descending thoracic aorta and aortic reinterventions. We compared the impact of an extensive repair at the index procedure using the Frozen Elephant Trunk (FET) technique, versus a conventional arch repair, on long-term remodelling of the descending thoracic and reintervention related to the aorta.

METHODS

Consecutive patients who underwent conventional arch repair (conventional group) or FET repair (FET group) for an ATAAD from September 2018 to November 2021 were included. Patients who died before discharge or were lost to follow-up prior to the first appointment were excluded from the analysis. Preoperative and postoperative computed tomography angiography was reconstructed and diameter of the true/false lumen of the remaining aorta was compared up to 1 year. Negative (increased total diameter ≥ 5 mm) aortic remodelling was collected for each computed tomography angiography, as well as aortic reinterventions. Comparison of demographic, anatomical, and perioperative complications data were performed using Wilcoxon test for continuous variables or Chi-square test for categorical covariates. The Kaplan-Meier method estimator was used to assess survival rates. The Log rank test was used to compare survival curves between the 2 groups.

RESULTS

Thirty nine patients were included, 22 in the conventional group and 17 in the FET group (82% males, mean age 60 ± 12 years). In the FET group, distal anastomosis was performed in zone 0 or 1 for 82% of patients using the simplified delivery technique. Median maximum preoperative descending aortic diameter was larger in the FET group (33 mm [30; 37] vs. 30 mm [28; 32] [P = 0.0172]). At 30 days, the rate of negative remodelling on the descending thoracic aorta was significantly higher in the conventional group (50%) than in the FET group (8%, P = 0.02). At 1 year, Kaplan-Meier analysis shown a freedom from descending aortic negative remodeling of 35.1% (95% confidence interval (CI) 18.7-66.1%) in conventional group and 44.9% (CI 95% 26.1-77.2%) in FET group with no significant difference. However, early negative remodelling was observed for the conventional group. Within a year, freedom from reintervention was observed for 74.4% (95% CI 57.1-97%) of patients in the conventional group and 75.5 (95% CI 57.1-99.7%) of patients in the FET group with no significant difference.

CONCLUSIONS

Negative evolution of descending aorta remains a challenge after ATAAD. An extensive repair using the FET technique during the index procedure seems to be associated with satisfying short-term remodelling of descending aorta.

Pleiotropic activities of succinate: The interplay between gut microbiota and cardiovascular diseases

Cardiovascular diseases (CVDs) continue to be a significant contributor to global mortality, imposing a substantial burden and emphasizing the urgent need for disease control to save lives and prevent disability. With advancements in technology and scientific research, novel mechanisms underlying CVDs have been uncovered, leading to the exploration of promising treatment targets aimed at reducing the global burden of the disease. One of the most intriguing findings is the relationship between CVDs and gut microbiota, challenging the traditional understanding of CVDs mechanisms and introducing the concept of the gut-heart axis. The gut microbiota, through changes in microbial compositions and functions, plays a crucial role in influencing local and systemic effects on host physiology and disease development, with its metabolites acting as key regulators. In previous studies, we have emphasized the importance of specific metabolites such as betaine, putrescine, trimethylamine oxide, and N,N,N-trimethyl-5-aminovaleric acid in the potential treatment of CVDs. Particularly noteworthy is the gut microbiota-associated metabolite succinate, which has garnered significant attention due to its involvement in various pathophysiological pathways closely related to CVDs pathogenesis, including immunoinflammatory responses, oxidative stress, and energy metabolism. Furthermore, we have identified succinate as a potential biomarker, highlighting its therapeutic feasibility in managing aortic dissection and aneurysm. This review aims to comprehensively outline the characteristics of succinate, including its biosynthetic process, summarize the current evidence linking it to CVDs causation, and emphasize the host-microbial crosstalk involved in modulating CVDs. The insights presented here offer a novel paradigm for future management and control of CVDs.

Risk assessment and disease burden of extreme precipitation on hospitalizations for acute aortic dissection in a subtropical coastal Chinese city

Background

Extreme precipitation events are becoming more frequent due to climate change. The present study aimed to explore the impacts of extreme precipitation on hospitalizations for acute aortic dissection (AAD) and to identify susceptible populations and quantify the corresponding disease burden.

Methods

The present study used a distributed lag nonlinear model (DLNM) with a quasi-Poisson function to investigate the association between extreme precipitation (≥95th percentile) and the risk of hospitalizations for AAD from 2015 to 2020 in Shantou, Guangdong Province, China.

Results

The significant adverse effects of extreme precipitation (relative to no precipitation) on daily AAD hospitalizations lasted from lag 5 [relative risk (RR): 1.0318, 95% confidence interval (CI): 1.0067-1.0575] to lag 9 (RR: 1.0297, 95% CI: 1.0045-1.0555) and reached its maximum at lag 7 (RR: 1.0382, 95% CI: 1.0105-1.0665). Males and older adult individuals (≥60 years) were more susceptible to extreme precipitation. A total of 3.68% (118 cases) of AAD hospitalizations were due to extreme precipitation.

Conclusion

Extreme precipitation was significantly correlated with AAD hospitalizations. Government departments should actively implement extreme precipitation intervention measures to strengthen the protection of males and the older adult (≥60 years) and effectively reduce AAD hospitalizations.

Aortic dissection induced by vascular endothelial growth factor inhibitors

Vascular endothelial growth factor (VEGF) contributes to angiogenesis and vasculogenesis. The occurrence and progression of tumors are accompanied by angiogenesis. Vascular endothelial growth factor inhibitors (VEGFI) have been used in anti-tumor treatment. However, aortic dissection (AD) is one of the VEGFI-associated adverse reactions with cute onset, rapid progression, and high case fatality rate. We collected case reports of VEGFI related to aortic dissection in PubMed and CNKI (China National Knowledge Infrastructure) from inception to 28 April 2022. Seventeen case reports were selected. The medication included sunitinib, sorafenib, pazopanib, axitinib, apatinib, anlotinib, bevacizumab, and ramucirumab. This review discusses the pathology, risk factors, diagnosis, and treatment of AD. Vascular endothelial growth factor inhibitors are related to aortic dissection. Although current literature lacks clear statistical evidence on the population, we offer points to encourage further confirmation of the best methods of care for these patients.

Thoracic aortic emergencies involving the aortic arch: An integrated cardiovascular surgical treatment approach

Thoracic aortic emergencies involving the aortic arch are potentially fatal conditions that require the entire surgical repertoire of conventional surgery, such as complete aortic arch replacement using the frozen-elephant-trunk technique, through hybrid procedures, to full surgical endovascular options with conventional or delivered/fenestrated stent-grafts. An interdisciplinary aortic team should choose the optimal treatment of the pathologies of the aortic arch, considering the morphology of the entire aorta, from the root to beyond the bifurcation, as well as the clinical comorbidities. The treatment goal is a complication-free postoperative result and lasting freedom from aortic reinterventions. Irrespective of the selected therapy method, patients should then be connected to a specialized aortic outpatient clinic. The aim of this review was to provide an overview of pathophysiology and current treatment options in emergencies of the thoracic aorta, also involving the aortic arch. We wanted to summarize the preoperative considerations, intraoperative settings, and strategies, as well the postoperative follow-up.

Genetic Association between the Levels of Plasma Lipids and the Risk of Aortic Aneurysm and Aortic Dissection: A Two-Sample Mendelian Randomization Study

Although a growing number of studies have attempted to uncover the relationship between plasma lipids and the risk of aortic aneurysm (AA), it remains controversial. Meanwhile, the relationship between plasma lipids and the risk of aortic dissection (AD) has not been reported on. We conducted a two-sample Mendelian randomization (MR) analysis to evaluate the potential relationship between genetically predicted plasma levels of lipids and the risk of AA and AD. Summary data on the relationship between genetic variants and plasma lipids were obtained from the UK Biobank and Global Lipids Genetics Consortium studies, and data on the association between genetic variants and AA or AD were taken from the FinnGen consortium study. Inverse-variance weighted (IVW) and four other MR analysis methods were used to evaluate effect estimates. Results showed that genetically predicted plasma levels of low-density lipoprotein cholesterol, total cholesterol, or triglycerides were positively correlated with the risk of AA, and plasma levels of high-density lipoprotein cholesterol were negatively correlated with the risk of AA. However, no causal relationship was found between elevated lipid levels and the risk of AD. Our study revealed a causal relationship between plasma lipids and the risk of AA, while plasma lipids had no effect on the risk of AD.