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Agrafiotis E, Mayer C, Grabenwöger M, Zimpfer D, Regitnig P, Mächler H, Holzapfel GA. Global and local stiffening of ex vivo-perfused stented human thoracic aortas: A mock circulation study. Acta Biomater 2023; 161:170-183. [PMID: 36849029 DOI: 10.1016/j.actbio.2023.02.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 01/25/2023] [Accepted: 02/20/2023] [Indexed: 02/27/2023]
Abstract
The effects of thoracic endovascular repair (TEVAR) on the biomechanical properties of aortic tissue have not been adequately studied. Understanding these features is important for the management of endograft-triggered complications of a biomechanical nature. This study aims to examine how stent-graft implantation affects the elastomechanical behavior of the aorta. Non-pathological human thoracic aortas (n=10) were subjected to long-standing perfusion (8h) within a mock circulation loop under physiological conditions. To quantify compliance and its mismatch in the test periods without and with a stent, the aortic pressure and the proximal cyclic circumferential displacement were measured. After perfusion, biaxial tension tests (stress-stretch) were carried out to examine the stiffness profiles between non-stented and stented tissue, followed by a histological assessment. Experimental evidence shows: (i) a significant reduction in aortic distensibility after TEVAR, indicating aortic stiffening and compliance mismatch, (ii) a stiffer behavior of the stented samples compared to the non-stented samples with an earlier entry into the nonlinear part of the stress-stretch curve and (iii) strut-induced histological remodeling of the aortic wall. The biomechanical and histological comparison of the non-stented and stented aortas provides new insights into the interaction between the stent-graft and the aortic wall. The knowledge gained could refine the stent-graft design to minimize the stent-induced impacts on the aortic wall and the resulting complications. STATEMENT OF SIGNIFICANCE: Stent-related cardiovascular complications occur the moment the stent-graft expands on the human aortic wall. Clinicians base their diagnosis on the anatomical morphology of CT scans while neglecting the endograft-triggered biomechanical events that compromise aortic compliance and wall mechanotransduction. Experimental replication of endovascular repair in cadaver aortas within a mock circulation loop may have a catalytic effect on biomechanical and histological findings without an ethical barrier. Demonstrating interactions between the stent and the wall can help clinicians make a broader diagnosis such as ECG-triggered oversizing and stent-graft characteristics based on patient-specific anatomical location and age. In addition, the results can be used to optimize towards more aortophilic stent grafts.
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Affiliation(s)
| | - Christian Mayer
- Department of Cardiac Surgery, Medical University of Graz, Austria
| | - Martin Grabenwöger
- Department of Cardiovascular Surgery, Clinic Floridsdorf, Vienna, Austria
| | - Daniel Zimpfer
- Department of Cardiac Surgery, Medical University of Graz, Austria
| | - Peter Regitnig
- Institute of Pathology, Medical University of Graz, Austria
| | - Heinrich Mächler
- Department of Cardiac Surgery, Medical University of Graz, Austria
| | - Gerhard A Holzapfel
- Institute of Biomechanics, Graz University of Technology, Graz, Austria; Department of Structural Engineering, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.
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Kuo MC, Meena RA, Ramos CR, Benarroch-Gampel J, Leshnower BG, Duwayri Y, Jordan WD, Rajani RR. Stent Graft Oversizing is Associated with an Increased Risk of Long-Term Left Ventricular Wall Thickening in Young Patients Following Thoracic Endovascular Aortic Repair. Ann Vasc Surg 2021; 76:66-72. [PMID: 33838243 DOI: 10.1016/j.avsg.2021.02.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/03/2021] [Accepted: 02/04/2021] [Indexed: 11/20/2022]
Abstract
BACKGROUND Left ventricular (LV) wall thickening occurs in patients following thoracic endovascular aortic repair (TEVAR). Clinical consequences of cardiovascular (CV) remodeling may be more significant younger patients with longer anticipated life spans. Risk factors for CV remodeling following TEVAR are unknown but may be related to graft size. METHODS A retrospective analysis was performed of a multicenter healthcare system including patients aged ≤60 who underwent TEVAR between 2011 and 2019 with at least 1 year follow-up computed tomography angiography imaging available. Standard perioperative variables, native aortic diameter, and stent graft specifications were collected. Graft oversizing was calculated by dividing proximal graft diameter by proximal aortic diameter on preoperative imaging. Posterior LV wall thickness was measured at baseline and interval increases were normalized to time-to-follow-up. Primary outcome was annual rate of posterior LV wall thickening. RESULTS One hundred one patients met inclusion criteria with a mean (SD) follow-up time of 1270 (693) days. Overall mean (SD) rate of LV wall thickness change was 0.534 (0.750) mm per year. Mean (SD) absolute LV wall thickness at most recent follow-up was 10.97 (2.85) mm for men, 9.69 (2.03) mm for women. Multivariate analysis demonstrated that higher rates of LV wall thickening were associated with narrower graft diameters (P = 0.0311). Greater absolute LV wall thickness at follow-up was associated with narrower grafts (P= 0.0155) and greater graft oversizing (P= 0.0376). Logistic regression demonstrated individuals who met criteria for LV hypertrophy were more likely to have narrower stent-grafts (P= 0.00798) and greater graft oversizing (P= 0.0315). CONCLUSIONS LV wall thickening occurred to a greater degree in individuals with narrower stent-grafts and higher rates of graft oversizing. This has significant implications for long-term cardiovascular health in younger patients may undergo TEVAR for atypical indications. Particular attention should be paid to long-term effects of stent-graft oversizing when selecting grafts in such populations.
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Affiliation(s)
| | - R Anthony Meena
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy, Emory University School of Medicine, Atlanta, GA
| | - Christopher R Ramos
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy, Emory University School of Medicine, Atlanta, GA
| | - Jaime Benarroch-Gampel
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy, Emory University School of Medicine, Atlanta, GA
| | - Bradley G Leshnower
- Department of Surgery, Division of Cardiothoracic Surgery, Emory University School of Medicine, Atlanta, GA
| | - Yazan Duwayri
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy, Emory University School of Medicine, Atlanta, GA
| | - William D Jordan
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy, Emory University School of Medicine, Atlanta, GA
| | - Ravi R Rajani
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy, Emory University School of Medicine, Atlanta, GA
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Kwiecinski J, Cheng CP, Uberoi R, Hadi M, Hempel P, Degel C, You Z. Thoracic aortic parallel stent-graft behaviour when subjected to radial loading. J Mech Behav Biomed Mater 2021; 118:104407. [PMID: 33740690 DOI: 10.1016/j.jmbbm.2021.104407] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 11/20/2020] [Accepted: 02/12/2021] [Indexed: 10/22/2022]
Abstract
To manage complex aortic arch disease using minimally invasive techniques, interventionalists have reported the use of multiple stent-graft devices deployed in a parallel configuration. The structural device-device and device-artery interactions arising during aortic arch parallel endografting, also known as chimney thoracic endovascular aortic repair (ch-TEVAR), is not well understood. Through the use of a radial force testing system we sought to characterise both the loading and deformation behaviour of parallel endografts in representative ch-TEVAR configurations. Four commercially available devices (Bentley BeGraft, Gore TAG, Gore Viabahn, and Medtronic Valiant) were subjected to uniform radial load individually, and in six combinations, to quantify loading profiles. Image data collected during testing were analysed to evaluate mechanical deformations in terms of gutters, chimney and main endograft compression, as well as graft infolding. Parallel endografting was found to increase radial loads when compared to standard TEVAR. Chronic outward force during ch-TEVAR was dependent on main endograft manufacturer, with TAG combinations leading to consistently higher loads than Valiant, but independent of chimney graft type. Endograft deformations were dependent on chimney graft type, with Viabahn combinations presenting with lower gutter areas and increased lumen compression than BeGraft. Chimney graft deformations were also influenced by deployment arrangement in the case of double ch-TEVAR. This study emphasizes the significant variability in both radial loads and mechanical deformations between clinically relevant ch-TEVAR configurations.
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Affiliation(s)
- Jakub Kwiecinski
- Department of Engineering Science, University of Oxford, Oxford, UK.
| | | | - Raman Uberoi
- Department of Vascular Surgery, Oxford University Hospitals NHS Trust, Oxford, UK
| | - Mohammed Hadi
- Department of Vascular Surgery, Oxford University Hospitals NHS Trust, Oxford, UK
| | | | | | - Zhong You
- Department of Engineering Science, University of Oxford, Oxford, UK
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Baptista-Strazzi APW, Aun R, Sincos IR, Tobita AM, Portugal MFC, de Paula VP, Kaufmann O, Wolosker N. Multilayer stents affect the final diameter of aortic aneurysms and maintain renal artery patency for a short time in a swine experimental model. Clinics (Sao Paulo) 2021; 76:e2812. [PMID: 34037071 PMCID: PMC8112104 DOI: 10.6061/clinics/2021/e2812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 04/13/2021] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVES We sought to analyze the hemodynamic effects of the multilayer flow-modulated stent (MFMS) in Thoracoabdominal aortic aneurysms (TAAAs). METHODS The hemodynamic effects of MFMS were analyzed in aortic thoracoabdominal aneurysms in experimental swine models. We randomly assigned 18 pigs to the stent or control groups and underwent the creation of an artificial bovine pericardium transrenal aneurysm. In the stent group, an MFMS (Cardiatis, Isnes, Belgium) was immediately implanted. After 4 weeks, we evaluated aneurysm sac thrombosis and renal branch patency by angiography, duplex scan, and morphological analysis. RESULTS All the renal arteries remained patent after re-evaluation in both groups. Aneurysmal sac thrombosis was absent in the control group, whereas in the stent group it was present in 66.7% of aneurysmal sacs (p=0.061).The mean final aneurysm sac diameter was significantly lower in the stent group (mean estimated reduction, 6.90 mm; p=0.021). The proximal neck diameter decreased significantly in the stent group (mean difference, 2.51 mm; p=0.022) and grew significantly in the control group (mean difference, 3.02 mm; p=0.007). The distal neck diameter increased significantly in the control group (mean difference, 3.24 mm; p=0.017). There were no significant findings regarding distal neck measurements in the stent group. CONCLUSION The MFMSs remained patent and did not obstruct the renal arteries within 4 weeks. In the stent group, the device was also associated with a significant decrease in aneurysmal sac diameter and a large proportion (albeit non-significant) of aneurysmal sac thrombosis.
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Association Between Targeted Aortic Segment Tortuosity and Stent-Graft–Induced New Entry After Thoracic Endovascular Aortic Repair for Aortic Dissection or Intramural Hematoma. AJR Am J Roentgenol 2020; 214:679-686. [DOI: 10.2214/ajr.19.21398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Histologic Analysis with the Newly Designed Exoskeleton Seal ® Stent-Graft in the Porcine Abdominal Aorta. Cardiovasc Intervent Radiol 2019; 42:1331-1342. [PMID: 31201508 DOI: 10.1007/s00270-019-02261-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 06/03/2019] [Indexed: 10/26/2022]
Abstract
PURPOSE To investigate the technical feasibility of a novel exoskeleton Seal® stent-graft and analyze early histologic changes in the porcine abdominal aorta. MATERIALS AND METHODS Six pigs received an abdominal stent-graft (Group I), and six received an iliac branch stent-graft (Group II). Groups were subdivided as follows: Group Ia, which received three bifurcated main-body stent-grafts; Group Ib, which received three bifurcated main-body stent-grafts with both iliac graft-stents; Group IIa, which received three simple uni-iliac tapered stent-grafts; and Group IIb, which received three uni-iliac tapered tapered stent-grafts with right straight limb and left branched limb. Statistical analyses were performed with the Wilcoxon signed-rank test and mixed-model regression analysis. RESULTS The primary technical success rate (< 24 h) was 83% because of two acute thromboses in the lumen of the stented abdominal aorta immediately after stent-graft placement. At 4 weeks, late thrombosis occurred in two pigs. Higher mean neointimal hyperplasia areas (23.5% vs. 16.2%; P = .047), neointimal hyperplasia thicknesses (545.5 μm vs. 422.2 μm; P = .001), and degrees of collagen deposition (2.71 vs. 2.33; P = .002) were observed at the bare-metal stent-graft compared with the proximal exoskeleton portion of the stent-graft, with no significant differences between the patent and occluded groups or among the four types of stent-grafts. CONCLUSIONS The exoskeleton stent-graft demonstrates 66% of patency rate during 1-month follow-up due to four cases of thromboses; however, the endothelialization on the junction of proximal graft showed no significant differences between the patent and occluded groups. Further studies should investigate long-term outcomes with prolonged neointimal hyperplasia.
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Fontana F, Macchi E, Piacentino F, Cardim LN, Marchi GD, Barbosa F, Piffaretti G, Novario R, Rampoldi AG, Fugazzola C. The Evaluation of Aortic Diameter Changes During Long-Term Follow-Up After Endovascular Treatment of Acute Blunt Traumatic Thoracic Aortic Injuries. Vasc Endovascular Surg 2018; 52:335-343. [DOI: 10.1177/1538574418765385] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Purpose: To evaluate the variations in aortic diameters and long-term results in patients who underwent thoracic endovascular aortic repair (TEVAR) for acute blunt traumatic thoracic aortic injuries (BTTAIs). Materials and Methods: We retrospectively evaluated 23 patients with a mean age of 39 years (range: 17-74 years) who underwent TEVAR for BTTAI between October 2000 and November 2014. All of the patients underwent computed tomography angiography (CTA) before hospital discharge as a baseline imaging for the subsequent follow-up examinations. The technical success, overall survival, and complications were evaluated. Furthermore, the aortic diameters outside of the stent-graft (1 cm proximal and 1 cm distal to the stent-graft) and the aortic diameters within the stent-graft (2 cm distal to the proximal end and 2 cm proximal to the distal end) were assessed. The diameters at baseline on CTA were compared with those of the latest available follow-up examination. Results: Technical success was 100% with a mean follow-up of 65.4 months (range: 12-171 months). No death was registered, and 2 (8.7%) of 23 endograft-related complications (1 stent-graft distal infolding and 1 endoleak 2 and 4 months after the procedure, respectively) were observed. An increase in aortic diameter either proximal or distal to the stent-graft (mean value 0.7 and 0.5 mm, respectively) or within the stent-graft (mean value of 0.5 mm for both proximal and distal diameters) was registered (mean follow-up at 65.4 months, range: 12-171 months). Conclusion: Aortic dilatation following TEVAR for BTTAI is minimal during long-term follow-up. Endovascular treatment represents a durable and safe option in acute BTTAIs.
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Affiliation(s)
- Federico Fontana
- Department of Radiology, University of Insubria, Circolo Hospital, Varese, Italy
| | - Edoardo Macchi
- Department of Radiology, University of Insubria, Circolo Hospital, Varese, Italy
| | - Filippo Piacentino
- Department of Radiology, University of Insubria, Circolo Hospital, Varese, Italy
| | | | - Giuseppe De Marchi
- Department of Radiology, University of Insubria, Circolo Hospital, Varese, Italy
| | - Fabiane Barbosa
- Department of Radiology, Niguarda Ca’Granda Hospital, Milano, Italy
| | - Gabriele Piffaretti
- Department of Surgery and Morphological Sciences, University of Insubria, Circolo Hospital, Varese, Italy
| | - Raffaele Novario
- Department of Clinical and Biological Sciences, University of Insubria,Circolo Hospital, Varese, Italy
| | | | - Carlo Fugazzola
- Department of Radiology, University of Insubria, Circolo Hospital, Varese, Italy
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Baptista Sincos APW, Mazzeo A, Sincos IR, Coelho Neto F, Wolosker N, Aun R, Leite KRM, Penido de Paula V, Kaufmann OG. Duplex scan and histologic assessment of acute renal injury in a kidney-kidney crosstalk swine experimental model. J Vasc Surg 2017; 68:588-595. [PMID: 28958477 DOI: 10.1016/j.jvs.2017.06.118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 06/16/2017] [Indexed: 01/09/2023]
Abstract
OBJECTIVE The objective of this study was to identify the effect of two left renal vasculature occlusion strategies on the duplex ultrasound-assessed rheology and histology of the contralateral kidney. METHODS Pigs were randomly assigned to one of two groups: left renal artery-only clamping (A group, n = 8) or left renal artery and vein clamping (AV group, n = 9). Bilateral renal parenchymal biopsy specimens were taken every 10 minutes for 90 minutes. Duplex ultrasound resistive index (RI) and pulsatility index (PI) were measured. Mixed models with normal distribution and first-order autoregressive correlation structure and generalized estimating equation models were used. Results are presented as adjusted means with standard errors, estimated proportions with standard errors, and line plots with 95% confidence intervals. RESULTS RI and PI increased in the nonischemic kidney. In A group animals, RI values increased significantly (P < .01) after 30 minutes of ischemia and PI increased significantly (P < .04) from 30 to 60 minutes of ischemia. The number of histologic abnormalities was higher in A group than in AV group biopsy specimens. The percentage of lesions increased significantly after 10 minutes in A group nonischemic kidneys (P < .02) and between 50 and 80 minutes in AV group nonischemic kidneys (P < .01). CONCLUSIONS Nonischemic kidneys were acutely affected by contralateral ischemia. Their function was more adversely affected by unilateral renal artery occlusion with preserved renal vein patency (A group).
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Affiliation(s)
| | - Angela Mazzeo
- Albert Einstein Israeli Institute of Teaching and Research and Albert Einstein Israeli College of Health Sciences, São Paulo, Brazil
| | - Igor Rafael Sincos
- Division of Vascular Surgery, Department of Surgery, Hospital Israelita Albert Einstein, São Paulo, Brazil
| | - Felipe Coelho Neto
- Division of Vascular Surgery, Department of Surgery, Hospital Israelita Albert Einstein, São Paulo, Brazil
| | - Nelson Wolosker
- Division of Vascular Surgery, Department of Surgery, Hospital Israelita Albert Einstein, São Paulo, Brazil
| | - Ricardo Aun
- Division of Vascular Surgery, Department of Surgery, Hospital Israelita Albert Einstein, São Paulo, Brazil
| | - Katia R M Leite
- Division of Pathology, Department of Anatomy, Clinics Hospital, University of São Paulo, São Paulo, Brazil
| | - Vitoria Penido de Paula
- Albert Einstein Israeli Institute of Teaching and Research and Albert Einstein Israeli College of Health Sciences, São Paulo, Brazil
| | - Oskar G Kaufmann
- Division of Vascular Surgery, Department of Surgery, Hospital Israelita Albert Einstein, São Paulo, Brazil
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Cervi E, Nodari F, Botteri E, Mazzeo G, Stefano B. Appearance and rapid evolution of thoraco-abdominal intramural hematoma after TEVAR. JRSM Cardiovasc Dis 2017; 6:2048004017710884. [PMID: 28616205 PMCID: PMC5461912 DOI: 10.1177/2048004017710884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 04/23/2017] [Accepted: 04/25/2017] [Indexed: 12/02/2022] Open
Abstract
Some studies consider the different physical properties of the stent graft when compared with the blood vessel on the basis of vascular lesions that may require further intervention. We present a case in which a patient developed an intramural hematoma at the distal landing of previous thoracic endovascular aortic repair (TEVAR) that required the relining with a flared prosthesis. During follow-up, we observed the appearance of more caudal hematoma. We decided to observe this lesion with close radiological controls. In order to prevent serious complication after the induction of TEVAR, accurate planning of the procedure is very important to study the impact of the prosthesis implanted in the cardiovascular system. In particular, oversize, radial forces and length of coverage have been taken into account. The adherence to follow-up is very important to precociously detect the lesions to avoid the onset of complication.
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Affiliation(s)
- Edoardo Cervi
- Vascular Surgery, Department of Clinical and Experimental Sciences, University of Brescia, Spedali Civili Hospital, Brescia, Italy
| | - Franco Nodari
- Vascular Surgery, Department of Clinical and Experimental Sciences, University of Brescia, Spedali Civili Hospital, Brescia, Italy
| | - Emanuele Botteri
- Vascular Surgery, Department of Clinical and Experimental Sciences, University of Brescia, Spedali Civili Hospital, Brescia, Italy
| | - Girolomina Mazzeo
- Vascular Surgery, Department of Clinical and Experimental Sciences, University of Brescia, Spedali Civili Hospital, Brescia, Italy
| | - Bonardelli Stefano
- Vascular Surgery, Department of Clinical and Experimental Sciences, University of Brescia, Spedali Civili Hospital, Brescia, Italy
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Ninomiya OH, Tavares Monteiro JA, Higuchi MDL, Puech-Leão P, de Luccia N, Raghavan ML, da Silva ES. Biomechanical Properties and Microstructural Analysis of the Human Nonaneurysmal Aorta as a Function of Age, Gender and Location: An Autopsy Study. J Vasc Res 2016; 52:257-64. [PMID: 26799837 DOI: 10.1159/000442979] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 12/01/2015] [Indexed: 11/19/2022] Open
Abstract
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.
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Affiliation(s)
- Otavio Henrique Ninomiya
- Division of Vascular and Endovascular Surgery, Department of Surgery, University of Sx00E3;o Paulo School of Medicine, Sx00E3;o Paulo, Brazil
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Nauta FJH, Conti M, Kamman AV, van Bogerijen GHW, Tolenaar JL, Auricchio F, Figueroa CA, van Herwaarden JA, Moll FL, Trimarchi S. Biomechanical Changes After Thoracic Endovascular Aortic Repair in Type B Dissection. J Endovasc Ther 2015; 22:918-33. [DOI: 10.1177/1526602815608848] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Thoracic endovascular aortic repair (TEVAR) has evolved into an established treatment option for type B aortic dissection (TBAD) since it was first introduced 2 decades ago. Morbidity and mortality have decreased due to the minimally invasive character of TEVAR, with adequate stabilization of the dissection, restoration of true lumen perfusion, and subsequent positive aortic remodeling. However, several studies have reported severe setbacks of this technique. Indeed, little is known about the biomechanical behavior of implanted thoracic stent-grafts and the impact on the vascular system. This study sought to systematically review the performance and behavior of implanted thoracic stent-grafts and related biomechanical aortic changes in TBAD patients in order to update current knowledge and future perspectives.
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Affiliation(s)
- Foeke J. H. Nauta
- Thoracic Aortic Research Center, Policlinico San Donato IRCCS, University of Milan, Italy
- Departments of Surgery and Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Department of Vascular Surgery, University Medical Center Utrecht, the Netherlands
| | - Michele Conti
- Department of Civil Engineering and Architecture, University of Pavia, Italy
| | - Arnoud V. Kamman
- Thoracic Aortic Research Center, Policlinico San Donato IRCCS, University of Milan, Italy
- Departments of Surgery and Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Department of Vascular Surgery, University Medical Center Utrecht, the Netherlands
| | | | - Jip L. Tolenaar
- Department of General Surgery, St. Antonius Hospital, Nieuwegein, the Netherlands
| | | | - C. Alberto Figueroa
- Departments of Surgery and Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | | | - Frans L. Moll
- Department of Vascular Surgery, University Medical Center Utrecht, the Netherlands
| | - Santi Trimarchi
- Thoracic Aortic Research Center, Policlinico San Donato IRCCS, University of Milan, Italy
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De Bock S, Iannaccone F, De Beule M, Van Loo D, Vermassen F, Verhegghe B, Segers P. Filling the void: A coalescent numerical and experimental technique to determine aortic stent graft mechanics. J Biomech 2013; 46:2477-82. [DOI: 10.1016/j.jbiomech.2013.07.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 06/21/2013] [Accepted: 07/09/2013] [Indexed: 11/27/2022]
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