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Objective: The purpose of our study was to describe perioperative kinetics of procalcitonin (PCT) in patients undergoing aortic surgery, to compare the kinetics in the open abdominal aortic aneurysm (AAA) repair and aortobifemoral bypass for aortoiliac occlusive disease (AIOD), and to evaluate the ability of PCT to detect intestinal ischaemia., Methods: A prospective non-randomized observational cohort study in 80 patients (62 men and 18 women) undergoing elective aortic surgery was performed. Serum PCT was measured at baseline and defined intraoperative and postoperative timepoints up to postoperative day 7. MRI contrast-enhanced imaging was used to detect intestinal ischaemia., Results: The comparison of the AAA and AIOD cohort did not show any significant difference in PCT levels. Patients with intestinal ischaemia had higher serum PCT at multiple timepoints postoperatively. The most accurate timepoints for early diagnosis were postoperative day 3, followed by 24 h after declamping of the vascular reconstruction, and postoperative day 7. The sensitivity and negative predictive values were 100% in all mentioned timepoints. However, event at the best timepoint the specificity was 89% and the positive predictive value 43%., Conclusions: Procalcitonin levels in the postoperative period at proper timepoints might help to detect postoperative intestinal ischaemia. The limitation of this marker is its low specificity for intestinal ischaemia and low positive predictive value. The highest value of this marker is that it can rule out this complication because normal PCT levels mean that intestinal ischaemia is very unlikely., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objectives: Acute intestinal ischemia is a severe complication of abdominal aortic surgery that is difficult to diagnose early and therefore to treat adequately and timely. In this study the perioperative kinetics of d-lactate and ischemia-modified albumin (IMA) are described and the predictive value of these markers for the early diagnosis of acute intestinal ischemia is assessed., Design & Methods: This non-randomised, single-centre cohort study enrolled 50 patients with abdominal aortic aneurysm (AAA) and 30 patients with aortoiliac occlusive disease (AOID). Serum d-lactate and IMA were assessed pre-, intra-, and postoperatively at eight defined time points., Results: The highest serum d-lactate was at 6 h after complete declamping of the vascular graft. The highest predictive power of d-lactate was at 3 h after complete declamping (AUC 0.857). IMA was found to be higher in the AAA group in ischemic patients 10 min after complete declamping than in the AOID group. The highest predictive values of IMA were at 1 h after aortic cross-clamping (AUC 0.758) and 3 and 6 h after complete declamping (0.745 and 0.721, respectively). Moreover, the multivariate model with both markers at 3 h after complete declamping improved the detection of intestinal ischemia (AUC 0.894)., Conclusions: Serum levels of IMA and d-lactate seem to be influential predictive markers for postoperative intestinal ischemia, especially after 3 h from complete declamping of vascular reconstruction., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Objectives: The aim of this study was to assess occlusion rates of saphenous veins treated with the VariClose vein sealing system., Methods: A retrospective analysis including a total of 64 patients from four centres from the Czech Republic. Occlusion was defined as a non-compressible vein with absence of flow with exception to the first 3 cm from the saphenofemoral or saphenopopliteal junction on duplex ultrasound., Results: In 64 patients a total of 79 veins were treated. Technical success of the procedure was achieved in 74 (94%) of cases. The mean follow-up was 5.5 months. The closure rates calculated by the Kaplan-Meier method at 1, 3, 6 and 12 months were 94%, 85%, 69% and 36%, respectively, and there were no significant differences between centers. The average difference in VCSS score before and after the procedure was 1.8., Conclusions: The present study demonstrated surprisingly worse occlusion rates than the current literature.

Background: Postoperative intestinal ischemia is a severe complication in abdominal aortic surgery. Early diagnosis is needed for adequate and timely treatment. We studied the postoperative kinetics of l-lactate in vascular patients to assess its value as a marker for early postoperative intestinal ischemia detection., Material and Methods: We performed a prospective non-randomized single-center observational cohort study in eighty elective patients, fifty operated on for abdominal aortic aneurysm (AAA) and thirty for aortoiliac occlusive disease (AIOD). Serum l-lactate was measured preoperatively, intraoperatively, and postoperatively at defined timepoints up to postoperative day 7. Intestinal ischemia was detected using MRI enterocolography. We have used univariate logistic regression and receiver operating characteristics curves for the evaluation of marker accuracy., Results: We recorded 6 cases of postoperative intestinal ischemia (7.5%), five non-transmural and one transmural. Two patients died because of this complication (mortality 33%). The comparison of AAA and AIOD cohorts showed a significant difference in l-lactate levels at one intraoperative timepoint, which was attributable to procedure differences. The only preoperative factor associated with higher l-lactate levels at some timepoints was chronic kidney disease. Patients suffering postoperative intestinal ischemia had elevated serum l-lactate levels at multiple timepoints. The most accurate timepoint for diagnosis was 24 h after the declamping of the vascular reconstruction (DC24H), the second was 10 min after declamping. Sensitivity, specificity, positive and negative predictive values at timepoint DC24H were 100%, 82%, 32%, and 100%, respectively., Conclusion: Serum l-lactate levels might help in the early detection of postoperative intestinal ischemia after aortic surgery if proper timepoints are used. Cutoff values need to be established in large-scale prospective studies., (Copyright © 2022 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.)

Purpose: There is no standard for measuring maximal diameter (Dmax) of abdominal aortic aneurysm (AAA) from computer tomography (CT) images although differences between Dmax evaluated from transversal (axialDmax) or orthogonal (orthoDmax) planes can be large especially for angulated AAAs. Therefore we investigated their correlations with alternative rupture risk indicators as peak wall stress (PWS) and peak wall rupture risk (PWRR) to decide which Dmax is more relevant in AAA rupture risk assessment., Material and Methods: The Dmax values were measured by a trained radiologist from 70 collected CT scans, and the corresponding PWS and PWRR were evaluated using Finite Element Analysis (FEA). The cohort was ordered according to the difference between axialDmax and orthoDmax (D a-o ) quantifying the aneurysm angulation, and Spearman's correlation coefficients between PWS/PWRR - orthoDmax/axialDmax were calculated., Results: The calculated correlations PWS/PWRR vs. orthoDmax were substantially higher for angulated AAAs (with D a-o ≥3mm). Under this limit, the correlations were almost the same for both Dmax values. Analysis of AAAs divided into two groups of angulated (n=38) and straight (n=32) cases revealed that both groups are similar in all parameters (orthoDmax, PWS, PWRR) with the exception of axialDmax (p=0.024)., Conclusions: It was confirmed that orthoDmax is better correlated with the alternative rupture risk predictors PWS and PWRR for angulated AAAs (D A-O ≥3mm) while there is no difference between orthoDmax and axialDmax for straight AAAs (D A-O <3mm). As angulated AAAs represent a significant portion of cases it can be recommended to use orthoDmax as the only Dmax parameter for AAA rupture risk assessment., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Aneurysms and pseudoaneurysms of the dorsalis pedis artery are rare vascular entities usually caused by traumatic injury or iatrogenic intervention, producing a focal soft pulsatile tissue mass in the dorsal foot. Gradual expansion of the fibrous capsule can produce secondary physical signs through the pressure exerted on surrounding structures. We report the case of a 57-year-old male with an idiopathic pseudoaneurysm of the dorsalis pedis artery. A focused history found a low-grade blunt trauma to the dorsal foot that had occurred 2 years previously. The diagnosis of a pseudoaneurysm was confirmed by ultrasound examinations and computed tomography angiograms. The pseudoaneurysm was treated with resection, and a short reversed great saphenous vein interposition graft was placed. He recovered well after surgery and remained free of symptoms 18 months postoperatively. The literature review of this uncommon vascular pathologic entity and the diagnosis and management are discussed., (Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.)

Aim of this study was to evaluate the possible use of infrared thermography as a supplementary method to the ankle-brachial index used in assessing the treatment effect of percutaneous transluminal angioplasty. The study included 21 patients, mean age was 60.22 years. Healthy control group included 20 persons, mean age was 55.60 years. Patients with symptomatic peripheral arterial disease (Fontaine stages I-III) were admitted for endovascular treatment by percutaneous transluminal angioplasty. Thermal images and ankle-brachial index values were obtained before and after treatment by percutaneous transluminal angioplasty. Median temperature change in the treated limb was 0.4℃, for non-treated limb was -0.5℃. The median value of ankle-brachial index in the treated limb increased by 0.17 from 0.81 after the procedure. The median value of ankle-brachial index in the non-treated limb decreased by 0.03 from the value of 1.01. Significant difference between treated limb and non-treated limb in change of ankle-brachial index was found with p value = .0035. The surface temperature obtained by the infrared thermography correlates with ankle-brachial index. We present data showing that the increase of ankle-brachial index is associated with increase of skin temperature in the case of limbs treated by percutaneous transluminal angioplasty. Our results also suggest potential of the use of infrared thermography for monitoring foot temperature as a means of early detection of onset of foot ischemic disorders.

Objective: Abnormal haemodynamics is commonly agreed to be a major contributor to the development of distal anastomotic intimal hyperplasia. A new vascular graft design proposed by computational studies was used to demonstrate its surgical feasibility and to compare it with the conventional graft in a porcine model., Method: The device was used in 12 eight-month-old pigs, six received the new graft and six had a conventional graft. The proximal graft end was implanted into the aorta, the distal graft end was implanted into the iliac artery. The host artery was ligated in order to simulate occlusion. At 20 weeks after surgery the pigs were killed and the device was excised for histological and morphometric analysis., Results: In five experimental grafts the reconstruction was occluded due to thrombosis; only one prosthesis was patent showing a minimum of neointimal hyperplasia. In the control group too only three of the six grafts were patent. A histological analysis revealed, as the cause of occlusion, fibrous tissue overgrowth corresponding in structure to neointimal hyperplasia. Differences in the number of obliterations and in occlusion rates between the profiles of the two groups were evaluated using the median test (P<0.05). The results were not statistically significant., Conclusion: Although mathematical modelling had shown significant haemodynamic benefits of a naturally bifurcated graft, our study did not confirm its superiority over conventionally used prostheses.

Arterial physiology relies on a delicate three-dimensional (3D) organization of cells and extracellular matrix, which is remarkably altered by vascular diseases like abdominal aortic aneurysms (AAA). The ability to explore the micro-histology of the aorta wall is important in the study of vascular pathologies and in the development of vascular constitutive models, i.e., mathematical descriptions of biomechanical properties of the wall. The present study reports and validates a fast image processing sequence capable of quantifying collagen fiber organization from histological stains. Powering and re-normalizing the histogram of the classical fast Fourier transformation (FFT) is a key step in the proposed analysis sequence. This modification introduces a powering parameter w, which was calibrated to best fit the reference data obtained using classical FFT and polarized light microscopy (PLM) of stained histological slices of AAA wall samples. The values of w = 3 and 7 give the best correlation (Pearson's correlation coefficient larger than 0.7, R 2 about 0.7) with the classical FFT approach and PLM measurements. A fast and operator independent method to identify collagen organization in the arterial wall was developed and validated. This overcomes severe limitations of currently applied methods like PLM to identify collagen organization in the arterial wall.

Background: Results of biomechanical simulation of the abdominal aortic aneurysm (AAA) depend on the constitutive description of the wall. Based on in vitro and in vivo experimental data several constitutive models for the AAA wall have been proposed in the literature. Those models differ strongly from each other and their impact on the computed stress in biomechanical simulation is not clearly understood., Methods: Finite element (FE) models of AAAs from 7 patients who underwent elective surgical repair were used to compute wall stresses. AAA geometry was reconstructed from CT angiography (CT-A) data and patient-specific (PS) constitutive descriptions of the wall were derived from planar biaxial testing of anterior wall tissue samples. In total 28 FE models were used, where the wall was described by either patient-specific or previously reported study-average properties. This data was derived from either uniaxial or biaxial in vitro testing. Computed wall stress fields were compared on node-by-node basis., Results: Different constitutive models for the AAA wall cause significantly different predictions of wall stress. While study-average data from biaxial testing gives globally the same stress field as the patient-specific wall properties, the material model based on uniaxial test data overestimates the wall stress on average by 30 kPa or about 67% of the mean stress. A quasi-linear description based on the in vivo measured distensibility of the AAA wall leads to a completely altered stress field and overestimates the wall stress by about 75 kPa or about 167% of the mean stress., Conclusion: The present study demonstrated that the constitutive description of the wall is crucial for AAA wall stress prediction. Consequently, results obtained using different models should not be mutually compared unless different stress gradients across the wall are not taken into account. Highly nonlinear material models should be preferred when the response of AAA to increased blood pressure is investigated, while the quasi-linear model with high initial stiffness produces negligible stress gradients across the wall and thus, it is more appropriate when response to mean blood pressure is calculated., (Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.)

Wall stress analysis of abdominal aortic aneurysm (AAA) is a promising method of identifying AAAs at high risk of rupture. However, neglecting residual strains (RS) in the load-free configuration of patient-specific finite element analysis models is a sever limitation that strongly affects the computed wall stresses. Although several methods for including RS have been proposed, they cannot be directly applied to patient-specific AAA simulations. RS in the AAA wall are predicted through volumetric tissue growth that aims at satisfying the homogeneous stress hypothesis at mean arterial pressure load. Tissue growth is interpolated linearly across the wall thickness and aneurysm tissues are described by isotropic constitutive formulations. The total deformation is multiplicatively split into elastic and growth contributions, and a staggered schema is used to solve the field variables. The algorithm is validated qualitatively at a cylindrical artery model and then applied to patient-specific AAAs (n = 5). The induced RS state is fully three-dimensional and in qualitative agreement with experimental observations, i.e., wall strips that were excised from the load-free wall showed stress-releasing-deformations that are typically seen in laboratory experiments. Compared to RS-free simulations, the proposed algorithm reduced the von Mises stress gradient across the wall by a tenfold. Accounting for RS leads to homogenized wall stresses, which apart from reducing the peak wall stress (PWS) also shifted its location in some cases. The present study demonstrated that the homogeneous stress hypothesis can be effectively used to predict RS in the load-free configuration of the vascular wall. The proposed algorithm leads to a fast and robust prediction of RS, which is fully capable for a patient-specific AAA rupture risk assessment. Neglecting RS leads to non-realistic wall stress values that severely overestimate the PWS.

The aim of this retrospective study was to evaluate the results of vascular operations based on the RaK prostheses, with a particular attention paid to their long-term patency. The study included 105 patients who were operated on in the period from 1992 to 1996. Vascular surgery was performed in the aortofemoral area and the underlying diagnoses were Leriche syndrome, asymptomatic abdominal aortic aneurysm, iliac artery stenosis or occlusion and symptomatic abdominal aortic aneurysm. During the mean follow-up time of 96 months (range 28-144), 8 patients (7.6 %) were lost to follow-up and 23 patients (21.9 %) died. At 12, 36, 60 and 120 months after surgery, the prostheses were patent in 99 %, 98 %, 93 % and 89 % of the patients, respectively. It is concluded that the RaK collagen prosthesis is the device of high quality and parameters comparable with the other types of knitted vascular prostheses currently used (Tab. 3, Fig. 4, Ref. 17).

Pedal bypass (arterial reconstruction with distal anastomosis on the dorsal pedal artery (DPA) or in the submalleolar portion of the posterior tibial artery) is now considered as a standard method of revascularisation in critically ischaemic limb with obliteration of the crural arterial system. While a number of studies in large cohorts have proved the success of this method in saving limbs with chronic critical ischaemia, only few papers report the pedal bypass as an urgent intervention. In this study, the authors describe 3 cases where urgent pedal bypass saved the limb threatened by an acute ischaemia (Fig. 3, Ref. 12).

In 1990, the vascular prosthesis of RaK type (collagen-impregnated knitted prosthesis), produced by the Research Institute of Hosiery in Brno, was introduced into clinical practice. In 1998, we published our experience with this type of prosthesis in form of a clinical evaluating study performed according to the methods of the EN 540 European Norm. Now we inform about the results of the studied group followed during 3 years. The long-term patency of the prosthesis in the aortic-phemoral part is 88.8%; the incidence of infection of the vascular prosthesis in our group studied in the 3-year period is 2.5%. Thus we can say that even long-term results confirm our previous good experience with this vascular prosthesis produced in Brno. (Tab. 8, Fig. 1, Ref. 11.)