Arterial Autografts Research Articles

V03-03 INNOVATIVE TECHNIQUE OF REDUCING REWARM ISCHEMIA TIME IN ROBOTIC ASSISTED KIDNEY TRANSPLANT WITH MULTIPLE VESSELS

You have accessJournal of UrologyCME1 Apr 2023V03-03 INNOVATIVE TECHNIQUE OF REDUCING REWARM ISCHEMIA TIME IN ROBOTIC ASSISTED KIDNEY TRANSPLANT WITH MULTIPLE VESSELS Himanshu Sharma, Samit Chaturvedi, Ruchir Maheshwari, and Anant Kumar Himanshu SharmaHimanshu Sharma More articles by this author , Samit ChaturvediSamit Chaturvedi More articles by this author , Ruchir MaheshwariRuchir Maheshwari More articles by this author , and Anant KumarAnant Kumar More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003241.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Robotic assisted kidney transplant (RAKT) is a feasible treatment option for patients with end stage renal disease. Despite the advantages of enhanced dexterity and wristed instruments, the problem of increased rewarm ischemia and longer vascular anastomosis time persists especially with multiple vessel renal allografts (MVRA). Our objective was to demonstrate technical feasibility of utilising the internal iliac artery autograft (IIAA) in RAKT to reduce rewarm ischemia times in a triple vessel renal allograft. METHODS: We present an innovative technique to utilize the internal iliac artery autograft in RAKT to manage MVRA which has never been reported previously. The donor had three vessels on left side and one single vessel on right side but the left kidney had lower glomerular filtration rate and smaller size in comparison to the right, so the left kidney was harvested laparoscopically. The technique is divided into three distinct steps. Step 1 is the retrieval of the IIAA, preparing the external iliac vessels for future anastomosis and raising a peritoneal flap for the transplant kidney. Step 2 involves bench dissection and ex-vivo vascular reconstruction to anastomose MVRA with IIAA. The final step is to anastomose this autograft-allograft complex with the external iliac vessels. RESULTS: We were able to perform a single in-vivo arterial anastomosis for a triple vessel renal allograft thereby reducing warm ischemia times. It took only 17 minutes to perform a single arterial anastomosis and if we would’ve done three anastomoses, the total rewarm ischemia time would have exceeded 60 minutes. Thus a single anastomosis enabled us to significantly reduce the rewarm ischemia time. CONCLUSIONS: Our technique eliminates the need for more than one arterial anastomosis, reduces the rewarm ischemia time and represents an innovative method to manage grafts with multiple vessels during RAKT. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e246 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Himanshu Sharma More articles by this author Samit Chaturvedi More articles by this author Ruchir Maheshwari More articles by this author Anant Kumar More articles by this author Expand All Advertisement PDF downloadLoading ...

Reconstructive plastic surgery in patients with complex defects and deformities of the head when removing extracerebral tumors extending beyond the cerebral skull

Objective: To improve the surgical results of neurosurgical patients with complex defects and deformities of the head based on modern innovative technologies. Маterials and methods. Based on the analysis of diagnosis and surgical treatment of 54 patients with common extracerebral tumors of the head the issues of optimizing their treatment were considered. The positive role of reconstructive-plastic operations in complex defects and deformities of the head on the basis of modern possibilities of computer modeling and use of arterial autografts is noted. Results. Carrying out computer simulations before the operation, radical removal of the tumor with a single-stage reconstructive-plastic operations with the use of innovative technologies provides high efficiency of treatment, satisfactory quality of life of patients. Conclusions. Reconstructive plastic surgery in patients with complex defects and deformities of the head when removing extracerebral tumors that extend beyond the cerebral skull, can provide a satisfactory functional and cosmetic effect of the operation. Radical removal of the tumor by a single-stage autologous tissue grafting using modern technologies promotes rapid wound healing and good quality of life. In patients with widespread cancer stages of the skull, for the plasty of complex soft tissue defects of the cranial vault, the optimal operation is the use of regional musculocutaneous flaps. The type, shape and required amount of the tissue depends on the size and location of the defect. It has been confirmed that the use of a horizontal D-shaped musculocutaneous flap is justified for temporal and parietal defect plasty, and the use of a vertical D-shaped musculocutaneous flap is required to close the occipital-parietal defect. The use of computer simulation is effective and appropriate in patients with large defects and deformities of the cerebral and facial skull when planning complex reconstructive plastic surgery. The use of modified surgical approaches, the latest innovative technologies has made it possible to significantly improve the quality of life of patients, contributed to their early rehabilitation and readaptation.

Vascular Remodeling of Clinically Used Patches and Decellularized Pericardial Matrices Recellularized with Autologous or Allogeneic Cells in a Porcine Carotid Artery Model.

Background: Cardiovascular surgery is confronted by a lack of suitable materials for patch repair. Acellular animal tissues serve as an abundant source of promising biomaterials. The aim of our study was to explore the bio-integration of decellularized or recellularized pericardial matrices in vivo. Methods: Porcine (allograft) and ovine (heterograft, xenograft) pericardia were decellularized using 1% sodium dodecyl sulfate ((1) Allo-decel and (2) Xeno-decel). We used two cell types for pressure-stimulated recellularization in a bioreactor: autologous adipose tissue-derived stromal cells (ASCs) isolated from subcutaneous fat of pigs ((3) Allo-ASC and (4) Xeno-ASC) and allogeneic Wharton’s jelly mesenchymal stem cells (WJCs) ((5) Allo-WJC and (6) Xeno-WJC). These six experimental patches were implanted in porcine carotid arteries for one month. For comparison, we also implanted six types of control patches, namely, arterial or venous autografts, expanded polytetrafluoroethylene (ePTFE Propaten® Gore®), polyethylene terephthalate (PET Vascutek®), chemically stabilized bovine pericardium (XenoSure®), and detoxified porcine pericardium (BioIntegral® NoReact®). The grafts were evaluated through the use of flowmetry, angiography, and histological examination. Results: All grafts were well-integrated and patent with no signs of thrombosis, stenosis, or aneurysm. A histological analysis revealed that the arterial autograft resembled a native artery. All other control and experimental patches developed neo-adventitial inflammation (NAI) and neo-intimal hyperplasia (NIH), and the endothelial lining was present. NAI and NIH were most prominent on XenoSure® and Xeno-decel and least prominent on NoReact®. In xenografts, the degree of NIH developed in the following order: Xeno-decel > Xeno-ASC > Xeno-WJC. NAI and patch resorption increased in Allo-ASC and Xeno-ASC and decreased in Allo-WJC and Xeno-WJC. Conclusions: In our setting, pre-implant seeding with ASC or WJC had a modest impact on vascular patch remodeling. However, ASC increased the neo-adventitial inflammatory reaction and patch resorption, suggesting accelerated remodeling. WJC mitigated this response, as well as neo-intimal hyperplasia on xenografts, suggesting immunomodulatory properties.

Long-term evolution of aortic arch interruption repair with pulmonary artery autograft

Surgical correction of the aortic arch interruption (IAA) is regularly complicated by anastomosis stenosis or the long-term occurrence of arterial hypertension. In order to prevent these complications, a new surgical technique has been developed in our center consisting of the interposition of a segment of the main pulmonary artery to enlarge the aortic anastomosis. The purpose of this study was to assess the 10 years outcome of this intervention. Four children undergoing this surgery with a follow-up over 10 years were retrospectively included. Data collected focused on the last measure of blood pressure (BP), the last echocardiographic evaluation, and the aortic arch dimension on the last CT. The whole patients had IAA type B and 22q11 microdeletion. The median follow-up duration was 13.9 years (range: 9.3 to 15.3). None of them had a new surgery of the aortic arch, but one need enlargement of ascending aorta. Only one patient developed a mild restenosis at the isthmic insertion of the pulmonary autograft [Z score −2.7 at CT ( Fig. 1 C)], responsible of mild arterial hypertension (systolic BP 75th percentile, diastolic BP 98th percentile), and a left ventricle hypertrophy (Z score IVSd 2.5, Z Score LVPWd 2.1). The three others patients displayed normal BP, no left ventricular hypertrophy, no significant aortic arch obstruction on Doppler evaluation and minimum Z score of aortic arch at CT from −1.8 to −0.4 ( Fig. 1 A, B, D). None of them did experience a main pulmonary artery stenosis. Reconstruction of the aortic arch with a pulmonary artery autograft for the correction of IAA provides a good long-term result.

Evaluation of the Stress-Growth Hypothesis in Saphenous Vein Perfusion Culture.

The great saphenous vein (GSV) has served as a coronary artery bypass graft (CABG) conduit for over 50years. Despite prevalent use, first-year failure rates remain high compared to arterial autograft options. Amongst other factors, vein graft failure can be attributed to material and mechanical mismatching that lead to apoptosis, inflammation, and intimal-medial hyperplasia. Through the implementation of the continuum mechanical-based theory of "stress-mediated growth and remodeling," we hypothesize that the mechanical properties of porcine GSV grafts can be favorably tuned for CABG applications prior to implantation using a prolonged but gradual transition from venous to arterial loading conditions in an inflammatory and thrombogenic deficient environment. To test this hypothesis, we used a hemodynamic-mimetic perfusion bioreactor to guide remodeling through stepwise incremental changes in pressure and flow over the course of 21-day cultures. Biaxial mechanical testing of vessels pre- and post-remodeling was performed, with results fit to structurally-motivated constitutive models using non-parametric bootstrapping. The theory of "small-on-large" was used to describe appropriate stiffness moduli, while histology and viability assays confirmed microstructural adaptations and vessel viability. Results suggest that stepwise transition from venous-to-arterial conditions results in a partial restoration of circumferential stretch and circumferential, but not axial, stress through vessel dilation and wall thickening in a primarily outward remodeling process. These remodeled tissues also exhibited decreased mechanical isotropy and circumferential, but not axial, stiffening. In contrast, only increases in axial stiffness were observed using culture under venous perfusion conditions and those tissues experienced moderate intimal resorption.

A Brief Report on an Implantation of Small-Caliber Biodegradable Vascular Grafts in a Carotid Artery of the Sheep.

The development of novel biodegradable vascular grafts of a small diameter (<6 mm) is an unmet clinical need for patients requiring arterial replacement. Here we performed a pre-clinical study of new small-caliber biodegradable vascular grafts using a sheep model of carotid artery implantation. The 4 mm diameter vascular grafts were manufactured using a mix of polyhydroxybutyrate/valerate and polycaprolactone supplemented with growth factors VEGF, bFGF and SDF-1α (PHBV/PCL-GFmix) and additionally modified by a polymer hydrogel coating with incorporation of drugs heparin and iloprost (PHBV/PCL-GFmixHep/Ilo). Animals with carotid artery autograft implantation and those implanted with clinically used GORE-TEX® grafts were used as control groups. We observed that 24 h following surgery, animals with carotid artery autograft implantation showed 87.5% patency, while all the PHBV/PCL-GFmix and GORE-TEX® grafts displayed thrombosis. PHBV/PCL-GFmixHep/Ilo grafts demonstrated 62.5% patency 24 h following surgery and it had remained at 50% 1 year post-operation. All the PHBV/PCL grafts completely degraded less than 1 year following surgery and were replaced by de novo vasculature without evidence of calcification. On the other hand, GORE-TEX® grafts displayed substantial amounts of calcium deposits throughout graft tissues. Thus, here we report a potential clinical usefulness of PHBV/PCL grafts upon their additional modification by growth factors and drugs to promote endothelialization and reduce thrombogenicity.

Reinforcing the pulmonary artery autograft in the aortic position with a textile mesh: a histological evaluation.

The Ross procedure involves replacing a patient's diseased aortic valve with their own pulmonary valve. The most common failure mode is dilatation of the autograft. Various strategies to reinforce the autograft have been proposed. Personalized external aortic root support has been shown to be effective in stabilizing the aortic root in Marfan patients. In this study, the use of a similar external mesh to support a pulmonary artery autograft was evaluated. The pulmonary artery was translocated as an interposition autograft in the descending thoracic aortas of 10 sheep. The autograft was reinforced with a polyethylene terephthalate mesh (n = 7) or left unreinforced (n = 3). After 6 months, a computed tomography scan was taken, and the descending aorta was excised and histologically examined using the haematoxylin-eosin and Elastica van Gieson stains. The autograft/aortic diameter ratio was 1.59 in the unreinforced group but much less in the reinforced group (1.11) (P < 0.05). A fibrotic sheet, variable in thickness and containing fibroblasts, neovessels and foreign body giant cells, was incorporated in the mesh. Histological examination of the reinforced autograft and the adjacent aorta revealed thinning of the vessel wall due to atrophy of the smooth muscle cells. Potential spaces between the vessel wall and the mesh were filled with oedema. Reinforcing an interposition pulmonary autograft in the descending aorta with a macroporous mesh showed promising results in limiting autograft dilatation in this sheep model. Histological evaluation revealed atrophy of the smooth muscle cell and consequently thinning of the vessel wall within the mesh support.

Biomechanics drive histological wall remodeling of neoaortic root: A mathematical model to study the expression levels of ki 67, metalloprotease, and apoptosis transition.

The pulmonary artery autograft (PA) is the ideal substitute for aortic valve disease in children and young adult. However, it is harnessed by the issue of long-term dilation and regurgitation, often requiring surgery. PA implanted in aortic position during the growth phase in children undergoes a process of mechanical remodeling. We previously developed a semiresorbable armored prosthesis able to mechanically sustain the neoaorta preventing dilation and to gradually integrate with the PA wall inducing a progressive arterial-like tissue positive remodeling. We also described the mechanisms of growth, remodeling and stress shielding of the reinforced PA through a mathematical model. We sought to demonstrate the biological counterpart and the potential molecular mechanisms underlying this histological and mechanical remodeling. A specific mathematical model was developed to describe mechanical behavior of the PA. Mallory trichrome red staining and immunohistochemistry for MMP-9 were performed to elucidate extracellular matrix remodeling phenomena. Apoptosis and cell proliferation were determined by TUNEL assay and immunohistochemistry for Ki67, respectively. An histological remodeling phenomenon sustained by increased level of MMP-9, augmented cell proliferation and reduced apoptosis in the reinforced PA was demonstrated. The mathematical model predicted the biomechanical behavior subtended by the histological changes of the PA in these settings. Changes in metalloproteinases (MMP-9), cell proliferation and apoptosis are the main actors in the remodeling process occurring after transposition of the PA into systemic regimens. Use of semiresorbable reinforcements might induce a positive remodeling of the PA in the context of Ross operation. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2785-2793, 2016.

Evaluation of artificial nerve conduit and autografts in peripheral nerve repair in the rat model of sciatic nerve injury

Objective: To investigate the therapeutic effect of artificial nerve conduit in the sciatic nerve injury and repair in the rat model.Methods: A total of 60 adult male Sprague Dawley rats were evenly randomized into five groups to build the model of sciatic nerve injury and perform the injury repair experiment. The five groups were: group A which was treated with artificial nerve conduit, group B which was treated with common carotid artery (CCA) autograft, group C which was treated with sciatic nerve autograft, group D which was treated with sham operation, and group E as the normal control. The injury was repaired by direct coaptation of the nerve ends. Postoperatively, the rats’ behavior, motor nerve conduction velocity (MNCV), incubation period, amplitude, remaining rate of wet weight of the gastrocnemius muscle, the diameter and section area of the gastrocnemius cell, and the histological changes were assessed. The results were analyzed by one-way ANOVA and two-way ANOVA.Results: Twelve days postoperatively, 36 rats in groups A, B, and C presented with denervated adermotrophia on the injured ankle. The electrophysiological indicators in groups D and E were constant and similar. The values of MNCV and amplitude were group C > group A > group B, with an increasing tendency. The values of the incubation period were group C < group A < group B with statistical difference (p < 0.05) and showed a decreasing tendency. The wet gastrocnemius muscle in groups D and E showed plump morphology with luster and elasticity. Groups A and C had similar atrophic gastrocnemius muscles and reduced flexibility while the phenomena were more severe in group B. Progressive decrease of the cell diameter and sectional area was observed in groups A, B, and C. The adhesion between the sciatic nerve and the surrounding area in groups A, B, and C had statistical significance (P < 0.05), with group B the most serious.Conclusions: The results suggest that artificial nerve conduit facilitated functional and morphological regeneration of the nerve. It seemed more effective than CCA but inferior to sciatic nerve autograft in repairing sciatic nerve injury in the rat model.

Open Repair of a Renal Artery Aneurysm with Hypogastric Artery Autograft and Hypothermic Perfusion Preservation

A 32-year-old woman presented with a one-year history of mild abdominal pain in the left upper quadrant and a palpable pulsatile abdominal mass on physical examination. The results of laboratory investigations, including serum urea and creatinine levels, were unremarkable.

Repair of Unilateral Absence of Right Pulmonary Artery With Contralateral Pulmonary Artery Autograft Interposition in an Infant

Unilateral absence of the pulmonary artery (PA) is a rare congenital abnormality. Although a traditional 2-stage approach with a preceding systemic-to-PA shunt followed by a definitive repair is mandatory in patients with absent extrapericardial pulmonary arteries, more creative solutions are necessary when 1-stage repair is concerned. We present anovel technique for repairing the absent intrapericardial right pulmonary artery (RPA) with a contralateral PA autograft segment interposition. We believe that this technique using solely autologous tissue is effective in patients in whom the intrapericardial segment of the PAs is absent.

Open Repair of a Renal Artery Aneurysm with Hypogastric Artery Autograft and Hypothermic Perfusion Preservation

Open Repair of a Renal Artery Aneurysm with Hypogastric Artery Autograft and Hypothermic Perfusion Preservation

Comparative Morphometric Analysis of 5 Interpositional Arterial Autograft Options for Adult Living Donor Liver Transplantation

In living donor liver transplantation, the right-sided graft presents thin and short vessels, bringing forward a more difficult anastomosis. In these cases, an interpositional arterial autograft can be used to favor the performance of the arterial anastomosis, making the procedure easier and avoiding surgical complications. ObjectiveWe compared the inferior mesenteric artery (IMA), the splenic artery (SA), the inferior epigastric artery (IEA), the descending branch of the lateral circumflex femoral artery (LCFA), and the proper hepatic artery (PHA) as options for interpositional autograft in living donor liver transplantation. MethodSegments of at least 3 cm of all 5 arteries were harvested from 16 fresh adult cadavers from both genders through standardized dissection. The analyzed measures were proximal and distal diameter and length. The proximal diameter of the RHA and the distal diameter of the SA, IMA, IEA and the LCFA were compared to the distal diameter of the RHA. The proximal and distal diameters of the SA, IEA and LCFA were compared to study caliber gain of each artery. ResultsAll arteries except the IMA showed statistical significant difference in relation to the RHA in terms of diameter. Regarding caliber gain, the arteries demonstrated statistical significant difference. All the harvested arteries except PHA were 3 cm in length. ConclusionThe IMA demonstrated the best compatibility with the RHA in terms of diameter and showed sufficient length to be employed as interpositional graft. The PHA, the SA, the IEA and the LCFA presented statistically significant different diameters when compared to the RHA. Among these vessels, only the PHA did not show sufficient mean length.

Aortic arch augmentation using a pulmonary artery autograft patch and a reversed left subclavian artery flap for an interrupted aortic arch type B complex

Adequate arch augmentation for interrupted aortic arch repair is quite important to avoid post-operative recoarctation and bronchial compression. We describe here two successful cases of aortic arch reconstruction using autologous materials such as a pulmonary artery patch and a reversed left subclavian artery flap in infants with an interrupted aortic arch type B complex.

Use of a Superficial Femoral Artery Autograft as a Femoral Vein Replacement During En Bloc Sarcoma Resection

Soft tissue malignancy encasing axial vessels presents a surgical challenge when the goal is limb-preserving radical excision. We describe a case where limb-preserving resection of a myxoid liposarcoma involving the femoral vessels was successfully performed in the absence of autologous superficial vein for vascular reconstruction. The proximal ipsilateral superficial femoral artery was harvested as an autograft for venous reconstruction, with the arterial defect bridged using a polytetrafluoroethylene interposition graft. This technique may be selectively extended to other indications where limb viability is dependent upon availability of a high-quality graft, and conventional conduits are either unavailable or unreliable.

Hypothenar Hammer Syndrome

Repetitive trauma to the hypothenar eminence can cause the ulnar artery to become aneurysmal, thrombose, or send emboli to the digital arteries. The symptoms and signs are also known as the hypothenar hammer syndrome. We postulate that an arterial autograft is a superior conduit to the traditional vein graft. In this article, we report 3 cases (2 in 1 patient) of reconstruction of the distal ulnar artery with the descending branch of the lateral circumflex femoral artery (LCFA). Two patients, ages 45 to 50 years, had severe ischemic complaints of the ulnar fingers. Arteriograms confirmed occlusion of the distal ulnar artery without direct perfusion of the superficial palmar arch. All reconstructions were carried out with the descending branch of the LCFA. From the ulnar artery at wrist level to the superficial palmar arch and the involved common digital arteries. Patency was certified during follow-up with color-coded Duplex sonography at 6 to 28 months. Preoperative complaints like cold intolerance and other ischemic symptoms disappeared.

Bypass Flap Reconstruction, A Novel Technique for Distal Revascularization: Outcome of First 10 Clinical Cases

Combined distal venous bypass grafting and free flap transfer can achieve successful treatment of soft tissue defects due to advanced leg ischemia. However, this combined approach is a complex technique involving multiple anastomoses on the same arterial axis with an increased risk of thrombosis. To reduce this risk, we have proposed a new bypass-flap (BF) reconstruction technique using an arterial graft and a free flap supplied by a collateral branch of the graft. The purpose of this report is to document the outcome in the first 10 patients treated using the BF reconstruction technique. From 2002 to 2004, a total of 10 patients with a mean age of 67 years (range 55-78) were treated using a BF. All patients presented critical ischemia with soft tissue defects resulting in exposure of tendons and muscles on the foot or ankle. Distal anastomosis was made between the distal branch of the BF and the pedal artery in five cases, the posterior tibial artery or plantar artery in four cases, and the peroneal artery in one case. In six cases proximal anastomosis was performed between the leg artery and arterial autograft. In the remaining four cases proximal anastomosis required extension of the bypass using a venous graft. The mean duration of hospitalization was 25 days. During the postoperative period, one patient died due to stercoral peritonitis and one patient required major amputation due to unrelenting sepsis. Bypass occlusion was not observed. Mean follow-up was 24 months (range 14-36). No patient was lost to follow-up and no patient died after the first 30 postoperative days. Follow-up examinations including clinical assessment and Doppler ultrasound imaging were performed at 3 months and every 6 months thereafter. Findings demonstrated bypass patency and healing of the covered defect in all cases. Outcome in this initial series demonstrates the clinical feasibility of the new BF reconstruction technique, which allows revascularization and coverage of tissue defects using a one-piece anatomic unit.

Repair of a Recurrent Pseudoaneurysm of the Ascending Aorta in an Atomic Bomb Survivor with Myelodysplastic Syndrome

The occurrence of infective aortic pseudoaneurysms tends to be intractable and difficult to treat. We experienced a very rare case of a recurrent infective pseudoaneurysm in the ascending aorta that occurred after cardiac surgery in an atomic bomb survivor with myelodysplastic syndrome. The pseudoaneurysm was successfully repaired using a femoral artery autograft with an omentopexy and the patient recovered well without any recurrence.

Superficial Femoral Artery Autograft Reconstruction for Complicated Popliteal Artery Entrapment Syndrome

We present an alternative surgical approach to popliteal artery entrapment syndrome with vascular complications in the absence of a suitable saphenous vein. Three patients (29, 35, and 78 years old) with thrombotic and/or aneurysmal lesions of the popliteal artery from popliteal artery entrapment syndrome were treated with superficial femoral artery autograft reconstruction. The procedure was performed through a medial approach. The superficial femoral artery was harvested in the upper third of the thigh and used as the conduit for reconstruction and the harvested segment was replaced by a polytetrafluoroethylene graft. At follow-up, patients were asymptomatic and duplex ultrasound revealed patent reconstruction with no morphological abnormalities.

Superficial femoral artery autograft reconstruction in the treatment of popliteal artery aneurysm: Long-term outcome

Superficial femoral artery autograft reconstruction in the treatment of popliteal artery aneurysm: Long-term outcome