Acute aortic syndromes: a review of what we know and future considerations

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.

Anzhen Risk Evaluation System for Acute Aortic Syndrome (AZSCORE-AAS): protocol for a multicentre prospective cohort study in northern China

INTRODUCTION

Acute aortic syndrome (AAS) is a group of acute and critical conditions, including acute aortic dissection (AAD), acute intramural haematoma and penetrating aortic ulcer. High mortality and morbidity rates result in a poor patient prognosis. Prompt diagnoses and timely interventions are paramount for saving patients' lives. In recent years, risk models for AAD have been established worldwide; however, a risk evaluation system for AAS is still lacking in China. Therefore, this study aims to develop an early warning and risk scoring system in combination with the novel potential biomarker soluble ST2 (sST2) for AAS.

METHODS AND ANALYSIS

This multicentre, prospective, observational study will recruit patients diagnosed with AAS at three tertiary referral centres from 1 January 2020 to 31 December 2023. We will analyse the discrepancies in sST2 levels in patients with different AAS types and explore the accuracy of sST2 in distinguishing between them. We will also incorporate potential risk factors and sST2 into a logistic regression model to establish a logistic risk scoring system for predicting postoperative death and prolonged intensive care unit stay in patients with AAS.

ETHICS AND DISSEMINATION

This study was registered on the Chinese Clinical Trial Registry website (http://www. chictr. org. cn/). Ethical approval was obtained from the human research ethics committees of Beijing Anzhen Hospital (KS2019016). The ethics review board of each participating hospital agreed to participate. The final risk prediction model will be published in an appropriate journal and disseminated as a mobile application for clinical use. Approval and anonymised data will be shared.

TRIAL REGISTRATION NUMBER

ChiCTR1900027763.

Acute aortic syndromes: An internist's guide to the galaxy

Acute aortic syndromes (AASs) are severe conditions defined by dissection, hemorrhage, ulceration or rupture of the thoracic aorta. AASs share etiological and pathophysiological features, including long-term aortic tissue degeneration and mechanisms of acute aortic damage. The clinical signs and symptoms of AASs are unspecific and heterogeneous, requiring large differential diagnosis. When evaluating a patient with AAS-compatible symptoms, physicians need to integrate clinical probability assessment, bedside imaging techniques such as point-of-care ultrasound, and blood test results such as d-dimer. The natural history of AASs is dominated by engagement of ischemic, coagulative and inflammatory pathways at large, causing multiorgan damage. Medical treatment, multiorgan monitoring and outcome prognostication are therefore paramount, with internal medicine playing a key role in non-surgical management of AASs.

Ascending aortic intramural hematoma: current concepts

PURPOSE OF REVIEW

Type A intramural hematoma (TAIMH) is an acute aortic disease characterized by the presence of hematoma in the aortic media and involving the ascending aorta. Open repair seems to be the first treatment approach, although recent evidence highlights that the best management of TAIMH is controversial. This review will focus on the current concept for TAIMH management and factors affecting the decision making.

RECENT FINDINGS

Recent studies have evaluated the role of open and endovascular repair, as well as conservative management in patients with TAIMH. More specific imaging findings seem to affect decision making for urgent repair.

SUMMARY

Despite TAIMH's acute nature, conservative management seems to represent a valid option for urgent approach, presenting similar mortality to open and endovascular repair. Comparative data are limited, however, in experienced centers, any approach may be applied with encouraging results. Endovascular management, which is mainly applied to manage retrograde TAIMH, is related to lower mortality and morbidity compared to open repair in this group of patients while aortic remodeling seems beneficial with this approach. Imaging findings, as ulcer-like lesions, hematoma thickness, concomitant dissection and aortic diameter, related to higher complication rate, set the indication for interventional management. Further research, including prospective data and registries, and ideally, randomized data may further clarify the best approach and factors indicating urgent repair.

Oxidative Stress in the Pathogenesis of Aorta Diseases as a Source of Potential Biomarkers and Therapeutic Targets, with a Particular Focus on Ascending Aorta Aneurysms

Aorta diseases, such as ascending aorta aneurysm (AsAA), are complex pathologies, currently defined as inflammatory diseases with a strong genetic susceptibility. They are difficult to manage, being insidious and silent pathologies whose diagnosis is based only on imaging data. No diagnostic and prognostic biomarkers or markers of outcome have been known until now. Thus, their identification is imperative. Certainly, a deep understanding of the mechanisms and pathways involved in their pathogenesis might help in such research. Recently, the key role of oxidative stress (OS) on the pathophysiology of aorta disease has emerged. Here, we describe and discuss these aspects by revealing some OS pathways as potential biomarkers, their underlying limitations, and potential solutions and approaches, as well as some potential treatments.