A Novel Model of Tobacco Smoke–Mediated Aortic Injury

Objective Tobacco smoke exposure is a major risk factor for aortic aneurysm development. However, the initial aortic response to tobacco smoke, preceding aneurysm formation, is not well understood. We sought to create a model to determine the effect of solubilized tobacco smoke (STS) on the thoracic and abdominal aorta of mice as well as on cultured human aortic smooth muscle cells (HASMCs). Methods Tobacco smoke was solubilized and delivered to mice via implanted osmotic minipumps. Twenty male C57BL/6 mice received STS or vehicle infusion. The descending thoracic, suprarenal abdominal, and infrarenal abdominal segments of the aorta were assessed for elastic lamellar damage, smooth muscle cell phenotype, and infiltration of inflammatory cells. Cultured HASMCs grown in media containing STS were compared to cells grown in standard media in order to verify our in vivo findings. Results Tobacco smoke solution caused significantly more breaks in the elastic lamellae of the thoracic and abdominal aorta compared to control solution ( P< .0001) without inciting an inflammatory infiltrate. Elastin breaks occurred more frequently in the abdominal aorta than the thoracic aorta ( P < .01). Exposure to STS-induced aortic microdissections and downregulation of α-smooth muscle actin (α-SMA) by vascular smooth muscle cells (VSMCs). Treatment of cultured HASMCs with STS confirmed the decrease in α-SMA expression. Conclusion Delivery of STS via osmotic minipumps appears to be a promising model for investigating the early aortic response to tobacco smoke exposure. The initial effect of tobacco smoke exposure on the aorta is elastic lamellar damage and downregulation of (α-SMA) expression by VSMCs. Elastic lamellar damage occurs more frequently in the abdominal aorta than the thoracic aorta and does not seem to be mediated by the presence of macrophages or other inflammatory cells.

Thoracic Aorta Diameter Calculation by Artificial Intelligence Can Predict the Degree of Arterial Stiffness

Background: Arterial aging is characterized by decreased vascular function, caused by arterial stiffness (AS), and vascular morphological changes, caused by arterial dilatation. We analyzed the relationship of pre-AS and AS, as assessed by cardio ankle vascular index (CAVI), with arterial diameters (AD) at nine levels, from the aortic sinus to the abdominal aorta, as measured by artificial intelligence (AI) on non-enhanced chest computed tomography (CT) images.Methods: Overall, 801 patients who underwent both chest CT scan and arterial elasticity test were enrolled. Nine horizontal diameters of the thoracic aorta (from the aortic sinuses of Valsalva to the abdominal aorta at the celiac axis origin) were measured by AI using CT. Patients were divided into non-AS (mean value of the left and right CAVIs [M.CAVI] &lt; 8), pre-AS (8 ≤ M.CAVI &lt; 9), and AS (M.CAVI ≥ 9) groups. We compared AD differences among groups, analyzed the correlation of age, ADs, and M.CAVI or the mean pressure-independent CAVI (M.CAVI0), Furthermore, we evaluated the risk predictors and the diagnostic value of the nine ADs for pre-AS and AS.Results: The AD at mid descending aorta (MD) correlated strongest with CAVI (r = 0.46, p &lt; 0.001) or M.CAVI0 (r = 0.42, p &lt; 0.001). M.CAVI was most affected by the MD AD and by age. An increase in the MD AD independently predicted the occurrence of pre-AS or AS. For MD AD, every 4.37 mm increase caused a 14% increase in the pre-AS and AS risk and a 13% increase in the AS risk. With a cut-off value of 26.95 mm for the MD AD, the area under the curve (AUC) for identifying the risk of AS was 0.743. With a cut-off value of 25.15 mm, the AUC for identifying the risk of the stage after the prophase of AS is 0.739.Conclusions: Aging is associated with an increase in AD and a decrease in arterial elasticity. An increase in AD, particularly at the MD level is an independent predictor of AS development.

Long-term outcomes of endovascular treatment for aortic pseudoaneurysm in patients with Behçet’s disease

Objectives Behçet’s disease (BD) is a multisystem inflammatory disorder with unknown etiology, and its aneurysmal lesions are associated with high mortality due to the high risk of rupture. This study intended to further explore the long-term safety and efficacy of endovascular therapy for BD-related aortic pseudoaneurysm (BAP). Methods From January 2009 to May 2021, 17 BAP patients who underwent endovascular repair were retrospectively identified and enrolled. Adequate immunosuppressive treatment was instituted before and after endovascular treatment unless emergency surgery was required. The patients were followed up at 3, 6, and 12 months and yearly after the primary endovascular intervention by computed tomography angiography (CTA) examination. Results Nineteen BAPs were identified among 17 patients. BAPs located at the aortic arch were found in three patients (17.6%), descending thoracic aorta in 5 (29.4%), and abdominal aorta in 10 (58.8%; suprarenal abdominal aorta in 2 [11.8%], and infrarenal abdominal aorta in 8 [47.1%]). The mean ESR during admission was 56.5 ± 24.9 mm/h (range = 30.0–120.0 mm/h), which fell to 22.7 ± 18.4 mm/h (range = 2.0–74.0 mm/h) before the endovascular intervention ( p < 0.001). The rate of favorable immunosuppressive control before intervention is 76.5% (13/17). Technical success was achieved in all patients. Median follow-up time was 57.0 months (interquartile range [IQR] = 21.3–67.3 months). Pseudoaneurysm recurrence was observed in four patients, type I endoleak in one, pseudoaneurysms sac dilation in one, and external iliac artery occlusion in 1. Two patients died of pseudoaneurysm rupture. Five-year accumulated overall rate, recurrence-free rate, and reintervention-free survival rate of BAP patients were 92.8%, 75.4%, and 71.8%, respectively. Conclusion Endovascular treatment in BAP patients seemed to be associated with long-term safety and efficacy with a 5-year overall survival rate of 92.8%. Adequate immunosuppressive treatment was essential for BAP patients to prevent aortic pseudoaneurysm recurrence and improve the prognosis.

Vascular abnormalities visualized by multislice computed tomography of the abdomen: accidental findings or immediate causes of pain syndrome? (topic review)

Abnormalities of the abdominal aorta branches may cause chronic mesenteric ischemia, progressive pathological changes of the internal organs in this setting, and chronic pain syndrome. The causes of chronic mesenteric ischemia may be divided into atherosclerotic and non-atherosclerotic. Atherosclerosis of the unpaired branches of the abdominal aorta involves stenosis or occlusion. Other causes include fibromuscular dysplasia, vasculitis (Takayasu, segmental mediolytic arteriopathy), and median arcuate ligament syndrome. These syndromes, the pathogenesis of some of which remains controversial, lead to nonspecific complaints such as abdominal pain, weight loss, and others. Digital subtraction angiography or duplex ultrasound may provide hemodynamic information in cases of vascular disease in this area. However, multislice spiral computed tomography is in many cases the first choice because it allows for a comprehensive assessment of the state of blood vessels and associated morphological changes of internal organs. Structural changes accompanying these syndromes can also occur in patients who are undergoing a medical examination for other reasons. However, these syndromes should not be diagnosed solely on the basis of imaging; instead, the findings should be compared with the clinical presentation, which implies collaboration of radiologists and clinicians.

Association of Abdominal Aorta Calcium and Coronary Artery Calcium with Incident Cardiovascular and Coronary Heart Disease Events in Black and White Middle‐Aged People: The Coronary Artery Risk Development in Young Adults Study

Background Assessing coronary artery calcium (CAC) is among AHA/ACC prevention guidelines for people at least 40 years old at intermediate risk for coronary heart disease (CHD). To study enhanced risk stratification, we investigated the predictive value of abdominal aorta calcium (AAC) relative to CAC for cardiovascular disease (CVD) and CHD events in Black and White early middle‐aged participants, initially free of overt CVD. Methods and Results In the CARDIA (Coronary Artery Risk Development in Young Adults) study, a multi‐center, community‐based, longitudinal cohort study of CVD risk, the CAC and AAC scores were assessed in 3011 participants in 2010–2011 with follow‐up until 2019 for incident CVD and CHD events. Distributions and predictions, overall and by race, were computed. During the 8‐year follow‐up, 106 incident CVD events (55 were CHD) occurred. AAC scores tended to be much higher than CAC scores. AAC scores were higher in Black women than in White women. CAC predicted CVD with HR 1.77 (1.52–2.06) and similarly for AAC, while only CAC predicted CHD. After adjustment for risk factors and calcium in the other arterial bed, the association of CAC with CVD was independent of risk factors and AAC, while the association of AAC with CVD was greatly attenuated. However, AAC predicted incident CVD when CAC was 0. Prediction did not vary by race. Conclusions AAC predicted CVD nearly as strongly as CAC and could be especially useful as a diagnostic tool when it is an incidental finding or when no CAC is found.

Morphometric analysis of the lumbar vertebrae and intervertebral discs in relation to abdominal aorta: CT-based study

Purpose Although lumbar discectomy is the most common procedure in spine surgery, reports about anatomical relations between discs and prevertebral vessels are limited. Aim of this research was to investigate morphometric of the lumbar region and the relations between intervertebral discs (IVDs) and abdominal aorta. Methods 557 abdominal computed tomography scans were assessed. For each spinal column level from Th12/L1 down to L4/L5, we investigated: intervertebral disc’s and vertebra’s height, width, length, and distance from aorta or common iliac artery (CIA). Those arteries were also measured in two dimensions and classified based on location. Results 54.58% of patients were male. There was a significant difference in arterial-disc distances (ADDs) between genders at the levels: L1/L2 (1.32 ± 1.97 vs. 0.96 ± 1.78 mm; p = 0.0194), L2/L3 (1.97 ± 2.16 vs. 1.15 ± 2.01 mm; p < 0.0001), L3/L4 (2.54 ± 2.78 vs. 1.71 ± 2.61 mm; p = 0.0012), also for both CIAs (left CIA 3.64 ± 3.63 vs. 2.6 ± 3.06 mm; p = 0.0004 and right CIA: 7.96 ± 5.06 vs. 5.8 ± 4.57 mm; p < 0.001)—those ADDs were higher in men at all levels. The length and width of IVD increased alongside with disc level with the maximum at L4/L5. Conclusion Bifurcations of the aorta in most cases occurred at the L4 level. Collected data suggest that at the highest lumbar levels, there is a greater possibility to cause injury of the aorta due to its close anatomical relationship with discs. Females have limited, in comparison to males, ADD at L1/L2, L2/L3, and L3/L4 levels what should be taken into consideration during preoperative planning of surgical intervention.

AT2R stimulation with C21 prevents arterial stiffening and endothelial dysfunction in the abdominal aorta from mice fed a high-fat diet

The aim of this study was to evaluate the effect of Compound 21 (C21), a selective AT2R agonist, on the prevention of endothelial dysfunction, extracellular matrix (ECM) remodeling and arterial stiffness associated with diet-induced obesity (DIO). &#160;5-week-old male C57BL/6J mice were fed a standard (Chow) or high-fat diet (HF) for 6 weeks. Half of the animals of each group were simultaneously treated with C21 (1mg/kg/day, in the drinking water), generating 4 groups: Chow C, Chow C21, HF C, HF C21. Vascular function and mechanical properties were determined in the abdominal aorta. To evaluate ECM remodeling, collagen deposition, activity of metalloproteinases (MMP) 2 and 9 and TGF-b1 concentration were analyzed in the plasma. Abdominal aortas from HF C mice showed endothelial dysfunction as well as enhanced contractile but reduced relaxant responses to Ang II. This effect was abrogated with C21 treatment by preserving NO availability. A left-shift in the tension-stretch relationship, paralleled by an augmented β-index (marker of intrinsic arterial stiffness), and enhanced collagen deposition and MMP-2/-9 activities were also detected in HF mice. However, when treated with C21, HF mice exhibited lower TGF-b1 levels in abdominal aortas together with reduced MMP activities and collagen deposition compared with HF C mice.&lt;/p&gt; &#160;In conclusion, these data demonstrate that AT2R stimulation by C21 in obesity preserves NO availability and prevents unhealthy vascular remodeling, thus protecting the abdominal aorta in HF mice against the development of endothelial dysfunction, ECM remodeling and arterial stiffness.