Abdominal Aortic Aneurysm: Natural History, Pathophysiology and Translational Perspectives.

An abdominal aortic aneurysm (AAA) is a degenerative pathology that affects the infrarenal segment of the aorta, leading to its progressive dilatation and eventually rupture. The infrarenal segment is involved in 80% of the aortic aneurisms, and represents alone 30% of all aneurysms. The natural history of the disease is characterized by the progressive increase of the aortic diameter associated with proportionally higher risk of rupture, particularly for cases with diameter greater than 5.5 cm. In case of rupture the mortality rate is very high, independently from the endovascular or surgical treatment. The most important risk factors are older age, smoking, hypertension, dyslipidemia, and family history of AAA. The most frequent form is "atherosclerotic", but infectious, collagen disease-related, immune dysregulation-related, and post-traumatic AAA have also been described. Albeit multiple pathogenetic hypotheses have been proposed, the role of metallo-proteinases in the degeneration of the aortic wall seem to play a central role. Early detection of AAA is crucial for the identification and treatment before the onset of potentially life-threatening complications. Moreover, the individual risk stratification is fundamental for the clinical management and follow-up. The growing knowledge about the pathophysiology of AAA has the potential to lead to significant translational advances. The challenge for the next years is to employ bioinformatic and genetic models, also based on artificial intelligence and machine learning approach, to develop novel screening methods and to stratify individuals at higher-risk or in the early stages of AAA.

How the First Year of the COVID-19 Pandemic Impacted Patients' Hospital Admission and Care in the Vascular Surgery Divisions of the Southern Regions of the Italian Peninsula.

Background: To investigate the effects of the COVID-19 lockdowns on the vasculopathic population. Methods: The Divisions of Vascular Surgery of the southern Italian peninsula joined this multicenter retrospective study. Each received a 13-point questionnaire investigating the hospitalization rate of vascular patients in the first 11 months of the COVID-19 pandemic and in the preceding 11 months. Results: 27 out of 29 Centers were enrolled. April-December 2020 (7092 patients) vs. 2019 (9161 patients): post-EVAR surveillance, hospitalization for Rutherford category 3 peripheral arterial disease, and asymptomatic carotid stenosis revascularization significantly decreased (1484 (16.2%) vs. 1014 (14.3%), p = 0.0009; 1401 (15.29%) vs. 959 (13.52%), p = 0.0006; and 1558 (17.01%) vs. 934 (13.17%), p < 0.0001, respectively), while admissions for revascularization or major amputations for chronic limb-threatening ischemia and urgent revascularization for symptomatic carotid stenosis significantly increased (1204 (16.98%) vs. 1245 (13.59%), p < 0.0001; 355 (5.01%) vs. 358 (3.91%), p = 0.0007; and 153 (2.16%) vs. 140 (1.53%), p = 0.0009, respectively). Conclusions: The suspension of elective procedures during the COVID-19 pandemic caused a significant reduction in post-EVAR surveillance, and in the hospitalization of asymptomatic carotid stenosis revascularization and Rutherford 3 peripheral arterial disease. Consequentially, we observed a significant increase in admissions for urgent revascularization for symptomatic carotid stenosis, as well as for revascularization or major amputations for chronic limb-threatening ischemia.