Disturbed flow in the juxta-anastomotic area of an arteriovenous fistula correlates with endothelial loss, acute thrombus formation, and neointimal hyperplasia.

Clinical failure of arteriovenous neointimal hyperplasia (NIH) fistulae (AVF) is frequently due to juxta-anastomotic NIH (JANIH). Although the mouse AVF model recapitulates human AVF maturation, previous studies focused on the outflow vein distal to the anastomosis. We hypothesized that the juxta-anastomotic area (JAA) has increased NIH compared with the outflow vein. AVF was created in C57BL/6 mice without or with chronic kidney disease (CKD). Temporal and spatial changes of the JAA were examined using histology and immunofluorescence. Computational techniques were used to model the AVF. RNA-seq and bioinformatic analyses were performed to compare the JAA with the outflow vein. The jugular vein to carotid artery AVF model was created in Wistar rats. The neointima in the JAA shows increased volume compared with the outflow vein. Computational modeling shows an increased volume of disturbed flow at the JAA compared with the outflow vein. Endothelial cells are immediately lost from the wall contralateral to the fistula exit, followed by thrombus formation and JANIH. Gene Ontology (GO) enrichment analysis of the 1,862 differentially expressed genes (DEG) between the JANIH and the outflow vein identified 525 overexpressed genes. The rat jugular vein to carotid artery AVF showed changes similar to the mouse AVF. Disturbed flow through the JAA correlates with rapid endothelial cell loss, thrombus formation, and JANIH; late endothelialization of the JAA channel correlates with late AVF patency. Early thrombus formation in the JAA may influence the later development of JANIH.NEW & NOTEWORTHY Disturbed flow and focal endothelial cell loss in the juxta-anastomotic area of the mouse AVF colocalizes with acute thrombus formation followed by late neointimal hyperplasia. Differential flow patterns between the juxta-anastomotic area and the outflow vein correlate with differential expression of genes regulating coagulation, proliferation, collagen metabolism, and the immune response. The rat jugular vein to carotid artery AVF model shows changes similar to the mouse AVF model.

IDEAL Phase 2a Results: Posterior Rectus Sheath Flap for Hiatal Augmentation in Complex Paraesophageal Hernias.

OBJECTIVE: To report the developmental phase results of posterior rectus sheath hiatal flap augmentation (PoRSHA), a promising surgical innovation for large and recurrent paraesophageal hernias. BACKGROUND: Durable hernia repair for large paraesophageal hernias continues to be a surgical challenge. PoRSHA addresses the challenges of current and historical approaches to complex paraesophageal hernias and demonstrates significant promise as a successful alternative approach. METHODS: Using the IDEAL framework, we outline the technical modifications made over the first 27 consecutive cases using PoRSHA. Outcomes measured included hernia recurrence on routine imaging at 6 months and 2 years, development of a postoperative abdominal wall eventration and incidence of solid food dysphagia. RESULTS: Twenty-seven patients at our single institution with type III (n=12), type IV (n=7), or recurrent (n=8) paraesophageal hernias underwent PoRSHA. Surgery was safely and successfully carried out in all cases. Stability of the technique was reached after 16 cases, resulting in 4 main repair types. At an average follow-up of 11 months, we observed no radiologic recurrences, no abdominal eventrations or hernias at the donor site, and 1 patient with occasional solid food dysphagia that resolved with dilation. CONCLUSIONS: PoRSHA can not only be safely added to conventional hiatal hernia repair with appropriate training but also demonstrates excellent short-term outcomes. While the long-term durability with 5-year follow-up is still needed, here we provide cautious optimism that PoRSHA may represent a novel solution to the long-standing high recurrence rates observed with current complex PEH repair.

Octogenarians undergoing pancreaticoduodenectomy: Assessing outcomes, disposition, and timing of chemotherapy.

BACKGROUND: Inclusion of pancreaticoduodenectomy has demonstrated higher rates of curative treatment in pancreatic cancer, yet prior research has suggested increased postoperative complications in octogenarians (patients older than 80 years). This study aimed to understand the impact of age on patients undergoing a pancreaticoduodenectomy, focusing on postoperative outcomes and return to intended oncologic treatment. MATERIALS AND METHODS: We conducted a single-institution retrospective cohort study for patients undergoing pancreaticoduodenectomy from 2007 to 2018. Collected data included demographics, preoperative comorbidities, and postoperative data (length of stay, 30-day mortality, 1-year mortality, infection, discharge location). Data were separated into 2 cohorts: octogenarians (≥ 80 years) and nonoctogenarians (< 80). χ2 and independent-sample t tests were used for analysis. RESULTS: A total of 649 patients underwent pancreaticoduodenectomy from 2007 to 2018; 63 (9.7%) were octogenarians. No differences were found in infectious complications (P = .607), 30-day mortality (P = .363), or 1-year mortality (P = .895). Octogenarians had a longer length of stay (P = .003) and were more likely to be discharged to skilled nursing facilities (P < .001). There was no significant difference in neoadjuvant chemotherapy administration, although octogenarians were less likely to receive adjuvant chemotherapy (P = .048) and declined adjuvant therapy at a higher rate (P = .003). CONCLUSION: Performing a pancreaticoduodenectomy in octogenarians can be safe and effective in a properly selected cohort. Although postoperative morbidity and mortality are similar to younger patients, elderly patients are more likely to be discharged to nursing facilities and less likely to receive adjuvant chemotherapy. This study suggests that age alone should not be a discriminating factor when discussing surgical therapy for pancreatic cancer treatment in octogenarians.

Pancreatic neuroendocrine tumors: Surgical outcomes and survival analysis.

BACKGROUND: Pancreatic neuroendocrine tumors are rare, with rising incidence and limited clinicopathological studies. METHODS: Adult patients with pNET at a single tertiary care center were retrospectively evaluated. RESULTS: In total, 87 patients with histologically confirmed pNET who underwent resection were evaluated. 11% of patients had functioning pNETs: 9 insulinoma and 1 VIPoma. The majority (88.5%) were nonfunctioning. The most common surgical procedure performed was distal pancreatectomy with splenectomy (36.8%). 35.6% of cases were performed with minimally invasive surgery (MIS). MIS patients had fewer postoperative complications, shorter length of stay, and fewer ICU admissions.Disease-free survival (DFS) was unaffected by tumor size (p = 0.5) or lymph node status (p = 0.62). Patients with high-grade (G3) tumors experienced significantly shorter DFS (p = 0.02). CONCLUSIONS: This series demonstrates that survival in patients with pNET is driven mostly by tumor grade, though overall most have long-term survival after surgical resection. Additionally, an MIS approach is efficacious in appropriately selected cases.

Diagnostic Colour Duplex Ultrasound for Type IIIb Endoleak.

INTRODUCTION: This report presents the treatment of an aortic endovascular aneurysm repair (EVAR) device failure, focusing on the use of colour duplex ultrasound (CDUS) to diagnose and confirm effective treatment of a type IIIb endoleak. REPORT: An 89 year old man with a history of EVAR was transferred to the authors' centre with complaints of abdominal pain and a pressure sensation behind the umbilicus. A previously stable 11 cm aneurysm sac was visualised on computed tomography angiography in addition to a newly suspected type IIIb endoleak, which was confirmed via CDUS. He underwent successful endovascular repair with a stent across the limb defect. The patient was discharged uneventfully and was followed for surveillance. DISCUSSION: Type IIIb endoleak is an underreported complication after EVAR. CDUS of type IIIb endoleak aided in localisation and characterisation of the graft failure, and confirmed successful endovascular treatment of the endoleak defect in the side limb. Locating the point of graft failure using CDUS preceding endovascular repair of type IIIb endoleaks guides interventions and repair outcomes. It is a rare opportunity to report a case of acute type IIIb endoleak with CDUS that definitively localised an endograft defect.