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Transplant Renal Artery Stenosis (TRAS) is the leading vascular complication following kidney transplantation (KT), causing premature allograft loss and increased post-KT mortality. While risk factors for TRAS, such as prolonged cold ischemia time and delayed graft function, are well-documented in deceased donor-KT, the risk factors remain less clearly defined in living donor-KT. This matched case-control study, conducted at a leading national transplant center predominantly performing living donor-KT, evaluated risk factors and long-term outcomes of clinical TRAS (cTRAS). cTRAS cases diagnosed from January 2009 to December 2022 were matched with four control kidney transplant recipients (KTRs) in a study powered to assess whether ex-vivo arterial vascular reconstruction of multiple renal arteries (VR-MRA) increases the risk of cTRAS. Among 2,454 KTs, 28 KTRs (1.14%) were diagnosed with cTRAS around 3.62 ± 1.04 months post-KT, with renal allograft dysfunction (92.86%) as the most common presenting feature. Notably, 27 cTRAS cases were successfully treated with endovascular intervention, yielding favorable outcomes over a 6–180 months follow-up period. The study identified ex-vivo VR-MRA as an independent risk factor for cTRAS (P < 0.001). cTRAS cases receiving timely treatment exhibited long-term outcomes in graft and patient survival similar to control KTRs. Early screening and timely intervention for cTRAS post-KT may improve graft and patient outcomes. [ABSTRACT FROM AUTHOR]

SUMMARY In this paper, we discuss a technique for weakly enforcing flow rate conditions in computational hemodynamics. In particular, we study the effectiveness of cutting lateral branches from the computational domain and replacing them with non-perturbing boundary conditions to simplify the geometrical reconstruction and the numerical simulation. All these features are investigated both in the case of rigid and compliant walls. Several numerical results are presented to discuss the reliability of the proposed method.Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Introduction: Limb-salvage surgery has become the mainstream approaches for the treatment of sarcoma in the lower extremity. In cases where the sarcoma infiltrates the primary vessel, concurrent resection of the vessels and vascular reconstruction are required to ensure sufficient resection and preservation of limb function. The objective of this study is to assess the clinical outcomes of patients who underwent vascular reconstruction utilizing synthetic grafts for limb salvage, specifically in terms of postoperative complications and limb functional status. Methods: Between September 2016 and October 2021, 15 consecutive patients who underwent 15 arterial and 3 venous reconstruction procedures were included in this retrospective study. Incidence of postoperative morbidity, graft patency, rate of limb salvage, and overall survival of patients were analyzed. Results: The median follow-up was 12.5 months (range, 4.5-72.0). Graft thrombosis occurred in 5 patients (33.3%) and graft occlusion occurred in 3 patients (20.0%). The median overall survival was 28.0 months with the estimated 2-year and 5-year overall survival of 57.8% and 43.4% respectively. The 1-year and 2-year estimated patency rates of arterial reconstructions were 82.3% and 62.1%, respectively. None of the included patients with limb amputation were observed as a consequence of severe vascular complications, while two patients underwent amputation due to the repeat recurrence, resulting in a limb salvage rate of 86.7%. Conclusion: Our results show that the combination of vascular reconstruction and oncologic resection is a feasible option for preserving limbs in cases of musculoskeletal sarcoma with vessel involvement in the lower extremity. When vascular reconstruction surgery is performed, synthetic substitutes can be effectively used with low perioperative morbidity and an acceptable rate of limb salvage. [ABSTRACT FROM AUTHOR]

Testicular germ cell tumors (TGCTs) are the leading cause of cancer-related death in males between the ages of 20 and 40. In the advanced stages, the combination of cisplatin-based chemotherapy and surgical excision of the remaining tumor can cure many of these patients. Vascular procedures may be required during retroperitoneal lymph node dissection (RPLND) in order to achieve the complete excision of all residual retroperitoneal masses. Careful assessment of pre-operative imaging and the identification of patients who could benefit from additional procedures are important for minimizing peri- and postoperative complications. We report on a case of a 27-year-old patient with non-seminomatous TGCT, who successfully underwent post-chemotherapy RPLND with additional infrarenal inferior vena cava (IVC) and complete abdominal aorta replacement using synthetic grafts. [ABSTRACT FROM AUTHOR]

Purpose: Extended resections in hepatopancreatobiliary (HPB) surgery frequently require vascular resection to obtain tumor clearance. The use of alloplastic grafts may increase postoperative morbidity due to septic or thrombotic complications. The use of suitable autologous venous interponates (internal jugular vein, great saphenous vein) is frequently associated with additional incisions. The aim of this study was to report on our experience with venous reconstruction using the introperative easily available parietal peritoneum, focusing on key technical aspects. Methods: All patients who underwent HPB resections with venous reconstruction using peritoneal patches at our department between January 2017 and November 2021 were included in this retrospective analysis with median follow-up of 2 months (IQR: 1–8 months). We focused on technical aspects of the procedure and evaluated vascular patency and perioperative morbidity. Results: Parietal peritoneum patches (PPPs) were applied for reconstruction of the inferior vena cava (IVC) (13 patients) and portal vein (PV) (4 patients) during major hepatic (n = 14) or pancreatic (n = 2) resections. There were no cases of postoperative bleeding due to anastomotic leakage. Following PV reconstruction, two patients showed postoperative vascular stenosis after severe pancreatitis with postoperative pancreatic fistula and bile leakage, respectively. In patients with reconstruction of the IVC, no relevant perioperative vascular complications occurred. Conclusions: The use of a peritoneal patch for reconstruction of the IVC in HPB surgery is a feasible, effective, and low-cost alternative to alloplastic, xenogenous, or venous grafts. The graft can be easily harvested and tailored to the required size. More evidence is still needed to confirm the safety of this procedure for the portal vein regarding long-term results. [ABSTRACT FROM AUTHOR]

Copyright of Der Chirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of the present study was to investigate the effect of miR-133b on atherosclerosis (AS). A mouse model of AS (AS group) was established, and serum levels of total cholesterol, triglyceride, high-density lipoprotein cholesterol and low-density lipoprotein (LDL) cholesterol were detected. The thoracic aorta tissues were subjected to hematoxylin and eosin staining for pathological examination. Mice were intravenously injected with microRNA (miR)-133b mimics (the miR-133b mimic + AS group) and miR-133b mimics negative control (the miR-133b NC + AS group). Normal mice were named the Sham group. Vascular reconstruction parameters, the Collagen/Vascular Area Ratio (CA/CVA) and serum inflammatory factors of mice in each group were detected. mRNA expression was measured by reverse transcription-quantitative PCR and protein expression was determined by western blot analysis. An in vitro model of AS was induced in vascular smooth muscle cells (VSMCs) using oxidized (ox)-LDL. CCK-8 and wound healing assays were used to detect cell proliferation and migration. Compared with the Sham group, mice of the AS group, the AS + miR-133b NC group and the AS + miR-133b mimic group had higher intima thickness (IT), tumor necrosis factor (TNF)-α and monocyte chemoattractant protein (MCP)-1 levels, as well as increased Notch1 and Jagged1 expression; and they had lower medial thickness (MT), CA/CVA ratio and Notch3 expression (all P<0.05). In addition, miR-133b mimic promoted the proliferation and migration, upregulated Notch1 and Jagged1, and downregulated Notch3 in ox-LDL-induced VSMCs. Taken together, miR-133b aggravates AS by activating the Notch signaling pathway, which could serve as a potential target for the treatment of AS. [ABSTRACT FROM AUTHOR]

Aim: Currently, there is no clear consensus on the role of extended pelvic resections for locally advanced or recurrent disease involving major vascular structures. The aims of this study were to report the outcomes of consecutive patients undergoing extended resections for pelvic malignancy involving the aortoiliac axis. Methods: Prospective data were collected on patients having extended radical resections for locally advanced or recurrent pelvic malignancies, with aortoiliac axis involvement, requiring en bloc vascular resection and reconstruction, at a single institution between 2014 and 2018. Results: Eleven patients were included (median age 60 years; range 31–69 years; seven women). The majority required resection of both arterial and venous systems (n = 8), and the technique for vascular reconstruction was either interposition grafts or femoral–femoral crossover grafts. The median operative time was 510 min (range 330–960 min). Clear resection margins (R0) were achieved in nine patients. The median length of stay was 25 days (range 7–83 days). Seven patients did not suffer an early complication. There was one serious complication (Clavien–Dindo ≥ 3), an arterial graft occlusion secondary to thrombus in the immediate postoperative period, requiring a return to theatre and thrombectomy. The median length of follow‐up in this study was 22 months (range 4–58 months). Conclusion: This series demonstrates that en bloc major vascular resection and reconstruction can be performed safely and can achieve clear resection margins in selected patients with locally advanced or recurrent pelvic malignancy at specialist surgery centres. [ABSTRACT FROM AUTHOR]

Copyright of Der Urologe A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Pseudoaneurysm after renal transplantation is a rare but serious complication. Case Presentation: We report a case of a 76-year-old man who presented six weeks after kidney transplant with a large pseudoaneurysm arising from the renal artery anastomosis, causing renal vein compression and renal allograft dysfunction. Prior to the removal of the transplanted kidney, an in situ cold perfusion of the allograft was performed. The pseudoaneurysm was repaired ex vivo and the renal artery was reconstructed. External iliac vein was reconstructed with deceased donor interposition allograft, and the kidney was then re-implanted. The patient recovered with immediate allograft function. Conclusions: Successful surgical management of a large renal allograft arterial pseudoaneurysm involves avoidance of dissection of the pseudoaneurysm, utilization of in situ cold perfusion and en-bloc removal of the kidney together with pseudoaneurysm, and pseudoaneurysm incision and vascular bypass reconstruction ex vivo. [ABSTRACT FROM AUTHOR]

Double inferior vena cava (d-IVC) is a subtype of vascular anomaly that rarely needs treatment. Here, we present a rare case of d-IVC accompanied with concurrent renal pelvis and bladder carcinoma. Due to misdiagnosis, the anomalous left inferior vena cava (IVC) entering the left renal vein was mistaken as the gonadal vein and was then severed during the radical nephroureterectomy. Fortunately, the injured left IVC was recognized correctly during the following cystectomy. The vascular reconstruction operation was performed to recanalize the left iliac veins by anastomosing the ligated vascular stump to the right IVC in an 'end-to-side' way. During the hospitalization, the patient was treated with 'low molecular weight heparin' and then warfarin to ensure an ideal international normalized ratio. He recovered well from the surgery. A meticulous and comprehensive analysis of radiographic imaging is critical to avoid misdiagnosis of d-IVC. [ABSTRACT FROM AUTHOR]

In living donor liver transplantation (LDLT), it is considered safer to reconstruct hepatic arteries (HAs) under a microscope than under conventional loupe magnification, because graft HA stumps are generally thin and short with an average diameter of approximately 2 mm. We first applied microvascular surgical techniques to HA reconstruction for LDLT in 1996. In most cases, we use a disposable double-clip to secure the graft and recipient arteries, and interrupted 8-0 nonabsorbable monofilament sutures. We next started performing resection and reconstruction of the right HA in a surgery for hilar cholangioma using the same technique as in LDLT. Lately, we have started applying microvascular surgical techniques to various digestive surgeries; namely, supercharge and superdrainage in esophageal surgery, vascular reconstruction in free jejunal interposition grafts for cervical esophageal cancer, resection and reconstruction of spontaneous HA aneurysms, jejunal artery reconstruction for spontaneous superior mesenteric artery dissections, and so forth. Mastering this technique is time consuming. However, once a surgeon masters the technique it has almost unlimited applications, and most vital vessels can be safely reconstructed using this method. We herein provide a technical review of the application of microvascular surgical techniques for various digestive surgeries. [ABSTRACT FROM AUTHOR]

Simple Summary: Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with poor prognosis and increased incidence. Surgical resection R0 remains the most important treatment to prolong survival in PDAC patients. In borderline and locally advanced cancer, vascular resection and reconstruction during pancreatectomy enables achieving R0 resection. This study is a comprehensive review of the literature regarding the role of venous and arterial resection with vascular reconstruction in the treatment of pancreatic cancer. Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with poor prognosis and increased incidence. Surgical resection R0 remains the most important treatment to prolong survival in PDAC patients. In borderline and locally advanced cancer, vascular resection and reconstruction during pancreatectomy enables achieving R0 resection. This study is a comprehensive review of the literature regarding the role of venous and arterial resection with vascular reconstruction in the treatment of pancreatic cancer. The literature review is focused on the use of venous and arterial resection with immediate vascular reconstruction in pancreaticoduodenectomy. Different types of venous and arterial resections are widely described. Different methods of vascular reconstructions, from primary vessel closure, through end-to-end vascular anastomosis, to interposition grafts with use autologous veins (internal jugular vein, saphenous vein, superficial femoral vein, external or internal iliac veins, inferior mesenteric vein, and left renal vein or gonadal vein), autologous substitute grafts constructed from various parts of parietal peritoneum including falciform ligament, cryopreserved and synthetic allografts. The most attention was given to the most common venous reconstructions, such as end-to-end anastomosis and interposition graft with the use of an autologous vein. Moreover, we presented mortality and morbidity rates as well as vascular patency and survival following pancreatectomy combined with vascular resection reported in cited articles. [ABSTRACT FROM AUTHOR]

A hemodynamic analysis of coronary blood flow must he based on the measured branching pattern and vascular geometry of the coronary vasculature. We recently developed a computer reconstruction of the entire coronary arterial tree of the porcine heart based on previously measured morphometric data. In the present study, we carried out an analysis of blood flow distribution through a network of millions of vessels that includes the entire coronary arterial tree down to the first capillary branch. The pressure and flow are computed throughout the coronary arterial tree based on conservation of mass and momentum and appropriate pressure boundary conditions. We found a power law relationship between the diameter and flow of each vessel branch. The exponent is ∼2.2, which deviates from Murray's prediction of 3.0. Furthermore, we found the total arterial equivalent resistance to be 0.93, 0.77, and 1.28 mmHg·ml-1·s-1·g-1 for the right coronary artery, left anterior descending coronary artery, and left circumflex artery, respectively. The significance of the present study is that it yields a predictive model that incorporates some of the factors controlling coronary blood flow. The model of normal hearts will serve as a physiological reference state. Pathological states can then be studied in relation to changes in model parameters that alter coronary perfusion. [ABSTRACT FROM AUTHOR]

The intraoperative transcutaneous partial pressure of oxygen (PtcO) was used to monitor 58 vascular reconstructive surgery procedures in 54 patients. The study comprised three groups: Group A (24 limbs without any ischemic symptoms or signs), Group B (45 limbs with intermittent claudication), and Group C (12 limbs with ischemic rest pain, ulceration, and gangrene). In addition in 31 patients the chest wall was monitored simultaneously as a control. The results showed that the PtcO values increased immediately and significantly to varying degrees and at varying speeds after unclamping. The controls had higher values than Group A ( P>0.05), Group B ( P<0.05), and Group C ( P<0.05) patients. Further study showed that there were no significant differences between the maximal values in the limbs with good distal vessel run-off in Groups A, B, and C, and in the controls ( P>0.05). It is thus concluded that effective vascular reconstruction in the limbs is indicated by a rapid and marked increase of both the PtcO value and the response value, while with a slow and low increase of the value, early graft failure and poor distal vessel run-off should be suspected. We believe that this monitoring method dynamically reflects the functional state during vascular reconstruction and is clinically valid. [ABSTRACT FROM AUTHOR]