Acute aortic occlusions (AAOs) are rare vascular emergencies associated with high morbidity and mortality. Presenting signs and symptoms vary but typically involve the lower extremities and include mottled skin with diminished pedal pulses, paresis, and severe pain. Prompt recognition and imaging are necessary to prevent rapid deterioration, which can lead to loss of limb or death. Treatment includes surgical or endovascular interventions based on patient-associated risk factors and clot location. We present a 76-year-old female who arrived at the emergency department with an AAO involving the infrarenal abdominal aorta and bilateral common iliac arteries. Efficient physical examination and utilization of computed tomography with angiography of the abdomen and pelvis allowed for the appropriate recognition of the AAO and subsequent successful surgical embolectomy. This case report underscores the importance of an expeditious clinical and radiographic evaluation in patients presenting with lower extremity pain and weakness.

We analyze the residual stresses and mechanical properties of layer-dissected infrarenal abdominal aorta (IAA). We measured the axial pre-stretch and opening angle and performed uniaxial tests to study and compare the mechanical behavior of both intact and layer-dissected porcine IAA samples under physiological loads. Finally, some of the most popular anisotropic hyperelastic constitutive models (GOH and microfiber models) were proposed to estimate the mechanical properties of the abdominal aorta by least-square fitting of the recorded in-vitro uniaxial test results. The results show that the residual stresses are layer dependent. In all cases, we found that the OA in the media layer is lower than in the whole artery, the intima and the adventitia. For the axial pre-stretch, we found that the adventitia and the media were slightly stretched in the environment of the intact arterial strip, whereas the intima appears to be compressed. Regarding the mechanical properties, the media seems to be the softest layer over the whole deformation domain showing high anisotropy, while the intima and adventitia exhibit considerable stiffness and a lower anisotropy response. Finally, all the hyperelastic anisotropic models considered in this study provided a reasonable approximation of the experimental data. The GOH model showed the best fitting.

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The estimation of blood flow-induced loads occurring on the artery wall is affected by uncertainties hidden in the complex interaction of the pulsatile flow, the mechanical parameters of the artery, and the external support conditions. To circumvent these difficulties, a specific tool is developed by combining the aorta displacements measured by an electrocardiogram-gated-computed tomography angiography, with the blood velocity field computed by a smoothed particle hydrodynamics (SPH) numerical model. In the present work, the SPH model has been specifically adapted to the solution of the 3D Navier-Stokes equations inside a domain with boundaries of prescribed motion. Images of the abdominal aorta aneurysm (AAA) of a 44-year-old female patient were acquired during a stabilized cardiac cycle by electrocardiogram-gated-computed tomography angiography. The in vivo kinematic field inside the pulsating arterial wall was estimated by using recent technology, which makes it possible to follow the shape of the arterial wall during a cardiac cycle. We compare the flow conditions and the blood-induced loads, computed by the numerical model under the assumption of a moving arterial wall, with the corresponding results obtained assuming three rigid wall geometries of the vessel during the cardiac cycle. Significant differences were found for the wall shear stress distribution.

OBJECTIVE: Vascular calcification is common and progressive in chronic kidney disease, including kidney transplant recipients (KTRs). However, the risk factors associated with the progression of aortic calcification (AoC) in KTRs have not been fully elucidated. In the present study, we evaluated AoC and examined the factors associated with its advancement in KTRs.
METHODS: This was a prospective longitudinal study that included 98 KTRs. We quantitatively investigated infrarenal abdominal AoC using the Agatston score, as measured by multi-slice computed tomography. After the baseline investigation, a follow-up scan was performed after 3 years, and the Agatston scores were obtained again. The changes in laboratory data affecting the 2nd Agatston scores were examined by multivariable analysis using non-linear regression after adjustment for several confounders.
RESULTS: The 2nd Agatston scores were significantly greater than the baseline Agatston scores (p < 0.001). After adjustment for the confounders, the change in corrected serum calcium exhibited a significant non-linear correlation with the 2nd Agatston scores (p = 0.022 for non-linearity/p = 0.031 for the effect of corrected serum calcium). Moreover, an interaction was present from the baseline AoC in the effect of corrected serum calcium on the progression of AoC, and the effect of hypercalcemia was greater in patients with higher baseline Agatston scores (p = 0.049).
CONCLUSIONS: The present study revealed that hypercalcemia is a risk factor for the development of infrarenal abdominal AoC in KTRs. Furthermore, the effect of hypercalcemia was greater in patients with more severe vascular calcification.

Atherosclerotic disease of the abdominal aorta is relatively common. However chronic stenosis of the infrarenal aorta is a fairly rare condition that has been traditionally treated with open endarterectomy and aorto-bifemoral bypass surgery. These surgeries may be associated with a significant increase in mortality and morbidity. Using 2 case examples we describe the feasibility of endovascular treatment of severely calcified infra-abdominal aortic lesion using a transradial endovascular approach that greatly reduce both vascular and access site complications.

In this paper, we hypothesize that the biaxial mechanical properties of the aorta may be dependent on arterial location. To demonstrate any possible position-related difference, our study analyzed and compared the biaxial mechanical properties of the ascending thoracic aorta, descending thoracic aorta and infrarenal abdominal aorta stemming from the same porcine subjects, and reported values of constitutive parameters for well-known strain energy functions, showing how these mechanical properties are affected by location along the aorta. When comparing ascending thoracic aorta, descending thoracic aorta and infrarenal abdominal aorta, abdominal tissues were found to be stiffer and highly anisotropic. We found that the aorta changed from a more isotropic to a more anisotropic tissue and became progressively less compliant and stiffer with the distance to the heart. We observed substantial differences in the anisotropy parameter between aortic samples where abdominal samples were more anisotropic and nonlinear than the thoracic samples. The phenomenological model was not able to capture the passive biaxial properties of each specific porcine aorta over a wide range of biaxial deformations, showing the best prediction root mean square error ε=0.2621 for ascending thoracic samples and, especially, the worst for the infrarenal abdominal samples ε=0.3780. The micro-structured model with Bingham orientation density function was able to better predict biaxial deformations (ε=0.1372 for ascending thoracic aorta samples). The root mean square error of the micro-structural model and the micro-structured model with von Mises orientation density function were similar for all positions.

Aortic cross-clamping-induced ischemia-reperfusion (IR) is an important factor in the development of postoperative acute cardiac injury following abdominal aortic surgery. We investigated the possible anti-oxidant/anti-inflammatory effects of fluoxetine (FLX), which is used widely as a preoperative anxiolytic on cardiac injury induced by IR of the infrarenal abdominal aorta. FLX was administered to IR-performed (60 min of ischemia and 120 min of reperfusion) rats for 3 days, once daily at 20 mg/kg i.p. dosage. Results were compared to control and non-FLX-treated IR-performed rats. Serum creatine kinase (CK) and CK-MB levels, lipid hydroperoxide, thiobarbituric acid reactive substances, and pro-oxidant/anti-oxidant balance levels in the IR group were significantly higher whereas superoxide dismutase activity, glutathione, and ferric reducing/anti-oxidant power levels were lower than for the control. IR also increased myeloperoxidase activity, tumor necrosis factor-α, interleukin-1β, and interleukin-6 and decreased interleukin-10 levels. FLX decreased CK, CK-MB, lipid hydroperoxide, thiobarbituric acid reactive substances, and pro-oxidant/anti-oxidant balance levels while increasing superoxide dismutase activity, glutathione, and ferric reducing/anti-oxidant power levels. FLX also decreased myeloperoxidase activity, tumor necrosis factor-α, interleukin-1β, and interleukin-6 levels and increased interleukin-10 levels compared to IR. FLX attenuated the morphological changes associated with cardiac injury. Our study clearly demonstrates that FLX confers protection against aortic IR-induced cardiac injury, tissue leucocyte infiltration, and cellular integrity via its anti-oxidant/anti-inflammatory effects.

BACKGROUND: Women affected by polycystic ovary syndrome (PCOS) are known to be at higher risk of cardiovascular disease. The aim of this study was to identify the artery that first is affected by early pre-atherosclerotic changes in PCOS.
METHODS: Twenty-nine women with PCOS aged 17 to 27 years and 26 healthy nonhyperandrogenic volunteers with regular menses (control women) aged 16 to 28 years were enrolled. All PCOS patients were overweight or obese (body mass index [BMI] > or = 25). Diagnosis of PCOS was performed in line with the 2003 Rotterdam ESHRE/ASRM-Sponsored PCOS Consensus Workshop Group. Accordingly, PCOS was defined when at least two of the following three features were present after exclusion of other etiologies: 1) oligomenorrhea and or anovulation; 2) hyperandrogenism and/or hyperandrogenemia; and 3) polycystic ovaries visible at ultrasound. Androgen excess or related disorders were excluded. The intima-media thickness (IMT) of common carotid arteries and common femoral arteries and the anteroposterior diameter of the infrarenal abdominal aorta were measured by ultrasound. Lutenizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, total testosterone, androstenedione, and sex hormone-binding globulin (SHBG) serum levels were measured between the 3rd and the 6th day of spontaneous or progestin-induced menstrual cycle. Our study was performed in the absence of any medical treatment.
RESULTS: Women with PCOS showed a higher LH to FSH ratio (p < 0.01), increased fasting insulin (p < 0.001), total testosterone (p < 0.001), and androstenedione (p < 0.001) levels, and lower SHBG concentrations (p < 0.001) compared to control women. BMI and waist-to-hip ratio were also higher in women with PCOS (p < 0.000 and p < 0.001, respectively). Women with PCOS also showed increased total cholesterol (p < 0.001), triglyceride (p < 0.001), and apolipoprotein B (p < 0.001) levels. Vascular data showed women with PCOS had a higher anteroposterior diameter than control women (p < 0.005). However, when analysis of covariance was performed and BMI was entered into the model as a covariate, anteroposterior diameter did not maintain a significant association with PCOS.
CONCLUSIONS: This study shows that anteroposterior diameter of the infrarenal abdominal aorta, but not IMT of common carotid arteries or common femoral arteries, is higher in women with PCOS than in women without this disease. This represents the earliest atherosclerotic change in women with PCOS. However, this alteration seems to be due to body weight secondary to PCOS and not due to PCOS per se.