Cysteine and glycine-rich protein 3 (Crp3) as a critical regulator of elastolysis, inflammation, and smooth muscle cell apoptosis in abdominal aortic aneurysm development.

Abdominal aortic aneurysm (AAA) is a life-threatening vascular disease for which surgical or endovascular repair are the only currently available therapeutic strategies. The development of AAA involves the breakdown of elastic fibers (elastolysis), infiltration of inflammatory cells, and apoptosis of smooth muscle cells (SMCs). However, the specific regulators governing these responses remain unknown. We previously demonstrated that Cysteine and glycine-rich protein 3 (Crp3) sensitizes SMCs to apoptosis induced by stretching. Building upon this finding, we aimed to investigate the influence of Crp3 on elastolysis and apoptosis during AAA development. Using the elastase-CaCl2 rat model, we observed an increase in Crp3 expression, aortic diameter, and a reduction in wall thickness in wild type rats. In contrast, Crp3-/- rats exhibited a decreased incidence of AAA, with minimal or no changes in aortic diameter and thickness. Histopathological analysis revealed the absence of SMC apoptosis and degradation of elastic fibers in Crp3-/- rats, accompanied by reduced inflammation and diminished proteolytic capacity in Crp3-/- SMCs and bone marrow-derived macrophages. Collectively, our findings provide evidence that Crp3 plays a crucial role in AAA development by modulating elastolysis, inflammation, and SMC apoptosis. These results underscore the potential significance of Crp3 in the context of AAA progression and offer new insights into therapeutic targets for this disease.

Biomechanical Analysis of Cadaveric Thoracic Aorta Zones: The Isthmus is the Weakest Region.

BACKGROUND: The thoracic aorta is a site of multiple pathological processes, such as aneurysms and dissections. When considering the development of endovascular devices, this vessel has been extensively manipulated because of aortic diseases, as well as to serve as a route for procedures involving the head and neck vessels. Therefore, the aim of the present study was to obtain biomechanical experimental information about the strength and deformability of this vessel. MATERIALS AND METHODS: Thirty-one thoracic aorta specimens were harvested during the autopsy procedure. They were carefully dissected and transversally sectioned according to Criado's aortic arch map landing zones (0 to 4). The supra-aortic trunks were removed, and the aortic rings were opened in their convexity, which resulted in flat tissue segments. Four millimeter-wide strips were prepared from each zone after which they were attached to a clip system connected to the INSTRON SPEC 2200 device, which was responsible for pulling the fragment up to its rupture during the uniaxial tension test. The INSPEC software was used to coordinate the test, and data management was conducted via the SERIES IX software. The biomechanical variables that were measured included failure stress, failure tension, and failure strain. RESULTS: When comparing the five segments from all 31 aortas, three different strength levels were observed. Zones 0 and 1 exhibited the highest failure stress and failure tension values, followed by Zones 2 and 4. Zone 3 (aortic isthmus) was the weakest segment that was tested when compared to the stress and tension of Zones 0 and 1 (P < 0.001), the stress and tension of Zone 2 (P = 0.005 and P = 0.002, respectively) and the stress and tension of Zone 4 (P = 0.023 and P = 0.006, respectively). Among donors > 65 years-old, women presented significantly weaker descending aortas than men in regards to stress (P = 0.049) and tension (P = 0.014). Among male donors, the elderly donors presented significantly stiffer aortic walls and weaker ascending (P = 0.029 for stress) and descending (P = 0.004 for stress; P = 0.031 for tension) aortas than younger men. CONCLUSIONS: Uniaxial tensile strength tests revealed that the thoracic aorta is a very heterogeneous vessel. Isthmus frailty may add to the understanding of the pathophysiology of some aortic diseases that commonly compromise this region. The lower strength that was verifiedin some aortic segments from elderly donors may contribute to the genesis of some thoracic aorta diseases among that group of donors. These data can contribute to the development of new endovascular devices that are specifically designed for this vessel.

Biomechanical and histological data from abdominal aortas harvested in autopsy.

This data article describes biomechanical and histological information of abdominal aortas harvested in autopsy. Eight abdominal aorta aneurysms (AAA) and 30 normal diameter abdominal aortas were collected and submitted to an inflation test up to their rupture. This inflation procedure was part of the research entitled "Experimental study of rupture pressure and elasticity of abdominal aortic aneurysms found at autopsy", submitted to Annals of Vascular Surgery. The rupture borders and control samples (harvested from places other than the rupture site) were submitted to uniaxial destructive tensile test and to histological analysis. The following variables were evaluated in the biomechanical test: failure stress, failure tension and failure strain. The histological processing of the samples enabled a quantitative analysis of the percentage of coverage of collagen fibers and elastic fibers in the samples. The present data could be reutilized because they are experimental evidence that cadaveric abdominal aortas, even when previously stressed by inflation, conserve significant resistance against tearing comparable to no previously stressed aortas described in the literature. Considering real whole cadaveric AAAs are especially scarce, this information would be a useful reference source for further in-depth research in the aortic biomechanics field.

Removal of Intravascular Foreign Bodies With a Simple Low-Cost Method: A Report of 5 Cases.

PURPOSE: Intravascular embolization of hemodialysis and central venous catheters is a rare but potentially serious complication. With the increasing use of catheters in medical practice, we are often faced with this type of complication. Novel, simple, and low-cost techniques are needed for foreign body extraction in order to reduce cardiovascular risks. CASE REPORT: We describe the approach of 5 foreign body embolization cases. Case 1: a 57-year-old woman with end-stage renal failure with a complete fracture and migration of the distal extremity of a hemodialysis catheter. Case 2: a 55-year-old man with an accidental embolization of the distal portion of a hemodialysis catheter. Case 3: a 76-year-old woman with stage IV breast cancer and an accidental embolization of a central venous catheter guidewire. Cases 4 and 5: a 71-year-old woman and a 2-year-old boy with a port-a-cath embolization. All the patients underwent successful minimally invasive removal of the foreign bodies from the thoracic site using 5Fr pigtail catheters. Additional surgery was not required. No further complications, such as damage to the vascular wall, were noted. CONCLUSION: Our experience with the interlacing and traction pigtail show that it is a simple, practical, and low-cost technical alternative and its benefits should be widespread.

Biomechanical Properties of the Periaortic Abdominal Tissue: It is Not as Fragile as It Seems.

BACKGROUND: The perivascular adipose tissue has been studied as a critical element that could influence physiological and disease processes of the vessel covered by it. In terms of anatomy, during the abdominal aorta's dissection, it is possible to identify the periaortic adipose tissue and the periaortic parietal peritoneum lying over it, sealing the retroperitoneal space. They seem to be fragile layers, with apparently no biomechanical role in the abdomen. However, it is well known that most cases of ruptured abdominal aortic aneurysms (AAAs) that reach the emergency department still alive present retroperitoneal bleeding contained by the previously mentioned two-layer combination, eventually allowing time for surgical treatment. In previous studies about aortic wall stress, tension, and AAA rupture prediction, only information concerning the vessel wall itself is highlighted. Therefore, the present work aims to study the biomechanical and histological properties of the periaortic tissue, comparing them to the same variables measured in aortic wall samples described in the medical literature. MATERIALS AND METHODS: Samples of periaortic tissue were harvested from 27 individuals during necropsy. Smoking status and the presence of AAAs were observed. Biomechanical uniaxial destructive tests were performed up to samples' rupture. Values of failure stress, tension, and strain were obtained. Samples were also harvested for histological analysis. RESULTS: Periaortic tissue presented less amount of collagen in smokers than in nonsmokers (P = 0.017). The periaortic tissue seems to be more elastic than aortic walls described in the literature (strain: 0.75 ± 0.37). Analyzing periaortic tissue failure stress (56.8 ± 101.26 N/cm2) and tension (7.65 ± 4.99 N/cm), it has at least 52% and 55%, respectively, of the stress and tension described in the medical literature for AAA walls. CONCLUSIONS: The periaortic tissue presents less collagen fibers in smokers than in nonsmokers. The periaortic tissue seemed very delicate during an autopsy, but the study of its biomechanical properties showed that it presents more than half of the resistance of an AAA wall. This information suggests this tissue might have a mechanical protective role against massive bleeding when it comes to an aortic rupture. Therefore this tissue's biomechanical information should be included in computational models on enlargement and rupture prediction of AAAs.

A randomized clinical trial of the effects of saphenous and perforating veins radiofrequency ablation on venous ulcer healing (VUERT trial).

OBJECTIVES: To investigate whether radiofrequency endovenous ablation (RFA) of saphenous and perforating veins increases venous leg ulcer (VLU) healing rates and prevents ulcer recurrence. METHOD: This prospective, open-label, randomized, controlled, single-center trial recruited 56 patients with VLU divided into: compression alone (CR, N = 29) and RFA plus compression (RF, N = 27). Primary endpoints were ulcer recurrence rate at 12 months; and ulcer healing rates at 6, 12, and 24 weeks. Secondary endpoints were ulcer healing velocity; and Venous Clinical Severity Score (VCSS). RESULTS: Recurrence was lower in the RF group (p < .001), as well as mean VCSS after treatment (p = .001). There were no significant between-group differences in healing rates. Healing velocity was faster in the RF group (p = 0.049). In the RF group, 2 participants had type 1 endovenous heat-induced thrombosis (EHIT). CONCLUSIONS: RFA plus compression is an excellent treatment for VLU because of its safety, effectiveness, and impact on ulcer recurrence reduction and clinical outcome.Registration: Clinicaltrials.gov, NCT03293836, clinicaltrials.gov.

Biomechanics data of human supra-aortic trunks and abdominal visceral arteries harvested during autopsy.

The present dataset describes the biomechanical properties of the supra-aortic trunks (brachiocephalic trunk, left common carotid artery, and left subclavian artery) and some of the visceral branches of the abdominal aorta (celiac trunk, superior mesenteric artery, and renal arteries). The specimens have been harvested from 27 adult donors during the autopsy procedure. The vessels were submitted to uniaxial biomechanical tensile tests, and values of failure stress, failure tension, and failure strain were obtained. As atherosclerosis could affect any of those vessels producing a significant reduction in their lumen, the data presented here could be of great interest to vascular surgeons, interventional cardiologists, and interventional neuroradiologists, who manipulate these arteries endovascularly. The observations gathered here are experimental evidence of the vessels' endurance against tearing and of their deformability. Therefore this data article could also help the medical industry dedicated to the production of endovascular devices. This dataset is related to the article entitled "Left Common Carotid Artery Biomechanical Properties in Individuals over 80 years: Women Have Stiffer Vessels" published in Annals of Vascular Surgery in August 2020 [1].

Study of the Biomechanical and Histological Properties of the Abdominal Aorta of Diabetic Rats Exposed to Cigarette Smoke.

INTRODUCTION: In spite of the great relevance of abdominal aortic aneurysm, its etiopathogenesis is not fully understood. The biomechanical and histological study of the aortic wall may contribute to this elucidation. METHODS: Seventy-five male Wistar rats were divided into 4 groups: control (CG), smoker (SG), diabetic (DG), and diabetic + smoker (DSG). The SG and DSG rats were exposed to cigarette smoke for 30 min/day, 5 days a week. Diabetes was induced by the intravenous injection of streptozotocin. After 16 weeks, the abdominal aorta was collected for biomechanical, histological, and matrix metalloproteinase 2 (MMP-2) activity analyses. RESULTS: The valid biomechanical tests of 52 specimens were analyzed: 11 in the CG, 10 in the DG, 16 in the SG, and 15 in the DSG. The biomechanical analysis of the fragments showed no differences between the control, DG, SG, and DSG. Collagen deposition also did not present a significant difference between the studied groups. The total count of elastic fibers was higher in diabetic rats (DG and DSG) than in the SG. The inflammatory response observed in all experimental groups was significantly more intense than in the CG. Compared to the DSG, MMP-2 activity showed a significant decrease in the DG. CONCLUSIONS: Resistance and elasticity did not present a difference between the CG and the DG, SG, and DSG. Compared to the CG, the total count of elastic fibers, fragmentation of the elastic lamina, pericellular matrix deposition, and cell loss/substitution in the tunica media showed significant alterations in the aortic walls of the DG, SG, and DSG. MMP-2 activity was lower in the DG aorta than in the DSG aorta.

Development of a Puncture Technique for Implanting Temporary Vascular Shunts in a Porcine Model.

BACKGROUND: Temporary vascular shunts (TVSs) are an effective tool for rapidly restoring blood flow to a limb or organ that has experienced vascular injury and ischemia and for which revascularization is not an immediate option. Usually, through an opening in the skin, the TVS is positioned within the proximal and distal stumps of the injured vessel, restoring perfusion and stopping the ischemia. The aim of this study is to compare standard TVS technique and a developed puncture technique for implanting TVS and to evaluate the utility and feasibility of this protocol after arterial lesions, in pigs. METHODS: Vascular injuries were inflicted in both hind limbs of 30 pigs, and vascular interventions were performed, using standard and puncture TVS. Because each pig was implanted with both types of TVSs, it was possible to simultaneously monitor, analyze, and compare parameters such as, the mean arterial pressure (MAP, in mm Hg), blood flow (mL/min), and insertion times, in the same animal. RESULTS: It was observed that the MAP in the limbs recovered and approached systemic MAP, in 100% of the experiments, in both groups. Analysis of the blood flow data showed that this parameter was significantly reduced in the puncture TVS group (110.36 ± 9.99 mL/min vs. 153.20 ± 18.57 mL/min, P = 0.001). On the other hand, the insertion time for the standard TVS was significantly greater than that of the puncture shunt (15.32 ± 3.08 min vs. 10.37 ± 1.7 min, P = 0.001). Furthermore, it was found that the primary and secondary patency and complication rates were similar for both TVS types. CONCLUSION: Thus, given the adequate MAP recovery and reduction in implantation time observed in this experimental and in an animal model study, the use of the puncture TVS technique is effective and feasible.

Investigation of the observed rupture lines in abdominal aortic aneurysms using crack propagation simulations.

OBJECTIVE: To use crack propagation simulation to study the rupture site characteristics in ruptured abdominal aortic aneurysms (AAA). METHODS: Rupture lines were precisely documented in four ruptured AAA harvested whole from cadavers. Wall thickness and material parameters were experimentally determined. Using subject-specific 3D geometry and subject-specific finite elastic model parameters, crack propagation simulations were conducted based on basic fracture mechanics principles to investigate if and how localized weak spots may have led to the observed rupture lines. RESULTS AND CONCLUSION: When an initial crack was imposed at the site of peak wall stress, the propagated path did not match the observed rupture line. This indicates that in this study population, the peak wall stress was unlikely to have caused the observed rupture. When cracks were initiated at random locations in the AAA along random orientations for random initial lengths, the orientation of the resulting propagated rupture line was consistently longitudinal. This suggests that the AAA morphology predisposes the AAA to rupture longitudinally, which is consistent with observations. It was found that, in this study population, rupture may have initiated at short segments of less than about 1 cm that then propagated to form the observed rupture lines. This suggests that ex vivo experimental and in vivo elastography studies should seek a spatial resolution (approx. 1 cm) to reliably identify weak spots in AAA. The small study population and lack of a reliable failure model for AAA tissue make these findings preliminary.

Medical Therapy for Asymptomatic Patients and Stent Placement for Symptomatic Patients Presenting with Carotid Artery Near-Occlusion with Full Collapse.

PURPOSE: To report long-term results of stent placement and medical therapy for symptomatic and asymptomatic patients, respectively, with carotid artery near-occlusion with full collapse. MATERIALS AND METHODS: Between January 2008 and December 2010, 204 carotid arteries diagnosed by duplex scanning as exhibiting complete occlusion were re-examined with CT angiography; 46 arteries in 46 patients were patent with threadlike lumens and were reclassified as exhibiting near-occlusion with full collapse. Asymptomatic patients (n = 22) received best medical therapy (BMT) alone, and symptomatic patients (n = 24) were referred for carotid artery stent (CAS) placement plus BMT. Patients underwent clinical follow-up for 63.9 months ± 23.6 and duplex surveillance. RESULTS: None of the 22 asymptomatic patients treated with BMT alone experienced neurologic events during the follow-up interval. Four died of unrelated causes, resulting in a cumulative survival rate of 81.8%. Technical failure occurred in 5 of 24 symptomatic patients, but none had perioperative complications related to inability to cross the near-occlusion. Of the 19 patients with procedural success, 1 developed immediate upper limb monoparesis; none had periprocedural myocardial infarction, and none died. At 60-month follow-up, patients who underwent successful CAS placement had neurologic event-free and cumulative survival rates of 89.4% and 89.4%; patients with failed recanalization had neurologic event-free and cumulative survival rates of 0% and 40.0% (P = .01). CONCLUSIONS: Asymptomatic patients with carotid near-occlusion with full collapse experienced good outcomes with BMT alone. Symptomatic patients who underwent CAS placement demonstrated long-term survival and freedom from neurologic event rates comparable to those of asymptomatic patients.

Endovascular Treatment of Penetrating Injury to the Vertebral Artery by a Stab Wound: Case Report and Literature Review.

BACKGROUND: We describe a unique case of a patient with penetration of the cervical region by a stab wound, who required emergency care for the controlled removal of the knife and for vertebral artery trauma (VAT) treatment. Although rare, VAT causes high morbidity and mortality. METHODS: A patient admitted for emergency care was diagnosed with traumatic complete section of the vertebral artery by a knife and underwent removal of the knife under radioscopic supervision and vertebral artery embolization with coils. RESULTS: The knife was removed successfully, the bleeding was controlled, and the patient did not present any sequelae. CONCLUSIONS: In the authors' experience, a patient in an emergent state due to VAT can be treated effectively and quickly with proximal embolization.

Carotid Plaque Morphology in Asymptomatic Patients with and without Metabolic Syndrome.

BACKGROUND: The aim of this study was to determine the impact of metabolic syndrome (MetS) on the morphology of carotid plaques, as evaluated using duplex ultrasound (DUS) with computer-assisted analysis. METHODS: In this cross-sectional observational study, we analyzed 148 carotid artery plaques in asymptomatic patients. Data were obtained via clinical and laboratory examinations, and DUS was performed by a single operator. All plaques were scanned in a longitudinal fashion, and the best segment was selected, recorded, and evaluated using dedicated software. The main software-based analyses included gray-scale median (GSM) measurements and carotid plaque morphology histograms. RESULTS: MetS was identified in 51.8% of patients. Comparisons of patients with MetS and patients without MetS indicated that the former patients used more classes of antihypertensive drugs (2.49 vs. 1.93; P = 0.004) and were treated with statins for a longer period (71.08 vs. 49.17 months; P = 0.003). Most patients of both types exhibited moderate carotid artery stenosis ranging from 50% to 69% (n = 62; 37.3%), and MetS was not associated with an increased prevalence of severe carotid artery stenosis. The mean GSM was greater in the MetS group than in the non-MetS group (74.18 vs. 61.63; P = 0.012). The histogram analysis revealed that there were lower quantities of blood and fat (2.91 vs. 3.88; P = 0.006; 10.21 vs. 15.08; P = 0.004, respectively) and more fibrous tissue (19.93 vs. 14.55; P = 0.015) in the carotid plaques of patients with MetS than in the carotid plaques of patients without MetS. CONCLUSIONS: The present study demonstrated that MetS did not affect the stenosis grade or did it lead to unstable carotid plaques.

Common Carotid Artery Occlusion: A Single-Center Experience in 40 Cases.

The incidence of common carotid artery occlusion (CCAO) is approximately 3% in patients who undergo angiography for symptomatic cerebrovascular disease; however, few studies have reported on management of this condition. The objective of this article was to analyze risk factors, therapeutic options, and clinical benefits of surgical treatment at a hospital in the city of São Paulo, Brazil. Data were collected from medical records of 40 patients with CCAO who were treated from June 2002 to October 2013. Results were analyzed retrospectively. Most of the patients were men (63.0%), who were significantly younger than women. Most of the participants had hypertension (90.0%), and more than half had a history of smoking (52.5%). The mean number of coexisting comorbidities/risk factors was 2.9 ± 1.0. Half of our sample had ipsilateral patent internal and external carotid artery, and 32.5% presented with an occluded internal carotid artery and a patent external artery. Patients with both an internal and an external occluded carotid artery (12.5%) were significantly older. Contralateral arteriosclerosis was observed in 65% of the patients, mainly represented by 50 to 90% stenosis. Most patients were symptomatic (67.5%), and hemiparesis was the most common symptom (55.0%) found. Most (77.5%) of the patients underwent the medical treatment; one out of three endovascular approaches failed. During the mean follow-up of 55 ± 43 months (range, 2-136 months), 17.5% of the patients died within 4 days after surgical repair and after along 123 months of clinical follow-up. Coexisting comorbidities/risk factors were significantly associated with fatal outcomes, such as acute myocardial infarction. This study provides scientific evidences on treatment and outcomes of CCAO.

Volumetry and biomechanical parameters detected by 3D and 2D ultrasound in patients with and without an abdominal aortic aneurysm.

The objective was to demonstrate the ability of ultrasound (US) with 3D properties to evaluate volumetry and biomechanical parameters of the aorta in patients with and without abdominal aortic aneurysm (AAA). Thirty-one patients with normal aortas (group 1), 46 patients with AAA measuring 3.0-5.5 cm (group 2) and 31 patients with AAA ⩾ 5.5 cm (group 3) underwent a 2D/3D-US examination of the infra-renal aorta, and the images were post-processed prior to being analyzed. In the maximum diameter, the global circumferential strain and the global maximum rotation assessed by 2D speckle-tracking algorithms were compared among the three groups. The volumetry data obtained using 3D-US from 40 AAA patients were compared with the volumetry data obtained by a contemporary computed tomography (CT) scan. The median global circumferential strain was 2.0% (interquartile range (IR): 1.0-3.0), 1.0% (IR: 1.0-2.0) and 1.0% (IR: 1.0-1.75) in groups 1, 2 and 3, respectively (p < 0.001). The median global maximum rotation decreased progressively from group 1 to group 3 (1.38º (IR: 0.77-2.13), 0.80º (IR: 0.57-1.0) and 0.50º (IR: 0.31-0.75), p < 0.001). AAA volume estimations by 3D-US correlated well with CT (R(2) = 0.76). In conclusion, US with 3D properties is non-invasive and has the potential to evaluate volumetry and biomechanical characteristics of AAA.

Analysis of risk factors and diseases associated with atherosclerosis in the progression of carotid artery stenosis.

OBJECTIVE: The objective of this study was to analyze the roles of demographic, clinical, and laboratory factors on the progression of atherosclerotic stenosis in carotid bifurcation. It was based on prospective information from records entered on a specific application form for follow-up outpatients at a tertiary university service. METHODS: Consecutive symptomatic and asymptomatic patients (n = 210) who had undergone more than one carotid duplex scan but no surgical intervention were selected for the analysis. The patients were divided into two groups: patients whose duplex scans did not show bilateral progression of carotid stenosis and patients with carotid stenosis progression of <50%, 50%-69%, or >70%. Clinical and demographic parameters were compared between groups. RESULTS: Group II levels of plasma urea (51.6 ± 27.8 mg/dl) and fibrinogen (493.2 ± 113.3 mg/dl) were higher than the Group I levels (43.0 ± 14.9 mg/dl and 441.3 ± 106.7 mg/dl, respectively) with statistical significance (p urea = 0.013 and p fibrinogen = 0.018). Paradoxically, the mean body mass index was higher in Group I (26.4 ± 4.6 kg/m(2)) than in Group II (24.6 ± 3.9 kg/m(2); p = 0.02). CONCLUSIONS: Traditional risk factors for the development of atherosclerosis in a carotid bifurcation are important but not unique. Metabolic and inflammatory factors can contribute to disease progression.

A prospective randomized study comparing polidocanol foam sclerotherapy with surgical treatment of patients with primary chronic venous insufficiency and ulcer.

BACKGROUND: To compare polidocanol foam sclerotherapy with surgical treatment of patients with primary chronic venous insufficiency and active ulcer treated at a single vascular center. METHODS: Fifty-eight limbs of 56 patients with active ulcers were prospectively randomized to undergo either surgical treatment or foam sclerotherapy. Patients completed the Aberdeen Varicose Veins Questionnaire (AVVQ), the Venous Clinical Severity Score (VCSS), and Venous Disability Score (VDS). The follow-up was 502 ± 220 days. RESULTS: The ulcer healed in 100% and 91.3% of patients treated with surgery or foam sclerotherapy, respectively (P > 0.05). There were no significant differences in AVVQ, VCSS, and VDS between the 2 groups after the procedures (P = 0.45, 0.58, and 0.66, respectively; Mann-Whitney U test). Complications occurred in 14.2% and 13.0% in the surgical and foam sclerotherapy groups, respectively. CONCLUSIONS: Surgical treatment and foam sclerotherapy achieved high rates of ulcer healing, without a statistically significant difference. Both treatments led to significant improvements in VCSS, VDS, AVVQ scores, demonstrating improvements in clinical outcomes and quality of life.

Biomechanical Properties and Microstructural Analysis of the Human Nonaneurysmal Aorta as a Function of Age, Gender and Location: An Autopsy Study.

INTRODUCTION: The biomechanical failure properties and histological composition of the human nonaneurysmal aorta were studied. METHODS: Twenty-six human aortas were harvested from fresh cadavers at autopsy. A total of 153 circumferentially oriented strips were obtained from the aortas for biomechanical and histological studies. RESULTS: The failure load (6.18 ± 2.03 vs. 4.85 ± 2.04 N; p = 0.001), failure tension (19.88 ± 9.05 vs. 14.53 ± 7 N/cm; p = 0.001), failure strain (0.66 ± 0.31 vs. 0.49 ± 0.25; p = 0.003) and amount of elastic fibers (19.39 ± 15.57 vs. 14.06 ± 9.5%; p = 0.011) were all significantly higher for the thoracic than the abdominal aorta. There was a significant negative correlation between age and failure load (R = -0.35; p < 0.0001), failure stress (R = -0.63; p < 0.0001), failure tension (R = -0.52; p < 0.0001) and failure strain (R = -0.8; p < 0.0001). Male aortas had a higher failure load and failure tension than female aortas. CONCLUSION: The thoracic aorta has a higher strength and elasticity than the abdominal aorta. The elderly have weaker and stiffer aortas than the young. Male aortas are stronger than female aortas.