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Objective: To investigate patency and clinical outcomes of alloplastic and other venous interposition graft materials in pancreatic surgery., Background: Vascular pancreatic surgery is increasingly performed for locally advanced pancreatic neoplasms. Different than other centers, we prefer to use alloplastic vascular graft materials for superior mesenteric vein and portal vein interposition in pancreatic surgery. Advantages are off-the-shelf availability at any customizable length, different diameters, and ring-enforcement but proposed concerns are their thrombogenicity and fatal complications., Methods: Patients who underwent elective pancreatic resections with mesoportal venous interposition grafts (ISGPS type 4) between 2003-2022 were identified from the institutional pancreatectomy registry. Alloplastic vascular grafts imply synthetic materials, either based on polytetrafluorethylene (PTFE) or polyethylene terephthalate (PET). Surgical details, clinicopathological, and follow-up data were analyzed. The patients were followed for graft patency by cross-sectional imaging., Results: In this study, 201 patients with venous interposition grafts were included (23% simultaneous arterial resections). Total pancreatectomy (41%) and pancreatoduodenectomy (35%) were the most frequent procedures. Vascular graft materials were alloplastic in 180 patients (83% PTFE and 17% PET) with a median diameter of 10 mm and a median length of 33 mm (measurement by CT scan). Patency rates among all graft materials at 7-, 30-, and 90-days were 99%, 93%, and 87%. Alloplastic grafts demonstrated superior patency over other materials (hazard ratio 2.7, P=0.009), and PTFE reached a 1-year patency of 78%. The all-cause 90-day mortality rate was 10%. No graft infection occurred., Conclusion: Alloplastic venous vascular grafts are safe and readily available tools in pancreatic surgery, especially for long-segmental mesoportal venous reconstructions., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Portal vein (PV) resection and reconstruction, which includes the resection and reconstruction of the PV and superior mesenteric vein, enable surgical removal of borderline resectable and locally advanced pancreatic cancer. Thrombosis of the reconstructed PV represents a major cause of early postoperative and long-term morbidity and mortality. No universally accepted standard for anticoagulation exists. This study aimed to assess early and late thrombosis rates after PV reconstruction with special regard to the type of PV reconstruction and anticoagulation regimen and to comprehensively assess thrombotic events and their clinical effect in patients receiving pancreatic surgery with venous resection and reconstruction., Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Studies reporting on PV resection and reconstruction providing data on thrombosis rates were included. The following parameters were assessed: study type, year of publication, number of patients, type/number of PV reconstruction, follow-up period, postoperative mortality, thrombosis rate of the reconstructed PV axis, intraoperative blood loss, and anticoagulation., Results: A total of 23 studies with 2751 patients were included in the final analysis. Of note, 670 patients received tangential resection of the PV with venorrhaphy or patch repair, 1505 patients had segmental resection with end-to-end reconstruction, and 576 patients received reconstruction with an interposition graft/conduit. The pooled overall thrombosis rate was 15%. Reconstruction of tangential defects with either venorrhaphy or patch repair and end-to-end repair of segmental defects resulted in a thrombosis rate of 12%. Subgroup analysis according to the type of graft reconstruction revealed the highest occlusion rates of 55% in patients with allogeneic grafts, followed by up to 27% in patients with synthetic PV conduits. Autologous conduits had a thrombosis rate of 10%. Early thrombotic events were detected in 5% of patients after venorrhaphy/patch reconstruction and end-to-end reconstruction. Early events were most common in the allogeneic graft subgroup (22%), followed by synthetic conduits (15%). There were fewer early events in the autologous graft group (7%). Early PV thrombosis was associated with relevant mortality of up to 26%. Anticoagulation regimens varied between studies., Conclusion: The overall thrombosis rate after PV resection is low. However, among the different reconstruction techniques, allogeneic interposition grafts/conduits had the highest thrombosis rates among the different types of reconstruction after PV resection. No specific anticoagulation strategy can be considered beneficial based on the existing literature., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Little is known about the prognostic significance of pancreatic duct (PD) dilation following pancreatoduodenectomy for intraductal papillary mucinous neoplasms (IPMN). Although PD dilation is typically the hallmark radiographic feature of IPMN, other causes of PD dilation exist, including anastomotic stricture, pancreatitis, senescence, and postsurgical passive dilation. Therefore, PD dilation after pancreatoduodenectomy for IPMN represents a diagnostic and management dilemma. The purpose of this study was to evaluate the significance of PD dilation after pancreatoduodenectomy for noninvasive IPMN., Methods: All patients who underwent pancreatoduodenectomy for noninvasive IPMN at nine pancreatic academic centers between 2013 and 2018 were included. Variables were entered prospectively into institutional databases and retrospectively reviewed for the purpose of this study. Dilation of the PD remnant was defined as a duct diameter of ≥5 mm, according to international guidelines., Results: Four-hundred and eighty-one patients were included in this study. The mean age of the patients was 66 years (range 30-90). Patients were surveilled for a median of 4.5 (+/-2.3; max 10.6) years. During follow-up, 132 patients (27.4%) developed PD dilation in the remnant tissue after a median of 3.3 years. Multivariable analysis demonstrated that older age at the time of pancreatoduodenectomy (P=0.01) and longer surveillance duration (P=0.002) were predictors of PD dilation. Interestingly, neither the pathological IPMN subtype (branch-duct vs. main duct/mixed, P=0.96) nor the preoperative PD diameter (P=0.14) was associated with an increased risk of PD dilation in the remnant. During follow-up, IPMN recurrence was suspected in the remaining 72 patients (18.4%), solely because of ductal dilation on cross-sectional imaging in 97% (70/72). Completion pancreatectomy was performed in only 16 patients (3.3%), of whom only four (0.8%) had invasive carcinoma. Three of these four patients had high-grade dysplasia in the original pancreatoduodenectomy specimen, whereas only one had a low-grade dysplastic lesion initially. On multivariable analysis, no variable was predictive of IPMN recurrence in the remnant., Conclusions: New main duct dilation in the pancreatic remnant after pancreatoduodenectomy for IPMN is common, occurring in 27% of the patients. The duration of surveillance is the main factor associated with remnant PD dilation, suggesting that this is likely a physiologic phenomenon. Although recurrence of IPMN in the remnant is often suspected, only 0.8% of patients develop an invasive carcinoma in the pancreatic remnant requiring completion pancreatectomy., Competing Interests: Disclosures and conflicts of interest: None reported., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: Our investigation on in-hospital mortality after 4474 pancreatoduodenectomies aimed to identify time-dependent risks as well as windows of opportunity to rescue patients from complications., Background: Pancreatoduodenectomy is generally considered a safe procedure with a 1-10% perioperative mortality based on complexity and surgical volume. Yet, patients are susceptible for life-threatening complications particularly with extended resections. Recognition of distinct vulnerabilities over time while patients recover is required to permit focused monitoring, sophisticated resource allocation, and greatest surgical safety., Methods: Patients who deceased in-hospital after pancreatoduodenectomy between 2003-2021 were retrieved from the institutional pancreatectomy registry and analyzed in detail with respect to their postoperative course., Results: Among 4474 pancreatoduodenectomies, 156 patients deceased in-hospital (3.5%). When assessing root causes of mortality, we observed 3 different clusters of complications which were postpancreatectomy-specific (47.4%), visceral vasculature-associated (25.6%), or cardiopulmonary in origin (23.7%). The median times of root cause onset in the 3 categories were postoperative day (POD) 9, POD 4.5 ( P =0.008) and POD 3 ( P <0.001), and medians of in-hospital mortality were POD 31, POD 18 ( P =0.009) and POD 8 ( P <0.001), respectively. Intervals between root cause onset and mortality varied with medians of 23 days, 11 days ( P =0.017), and 1 days ( P <0.001). The 3 categories were similarly distributed between different types of surgical complexity., Conclusion: Postpancreatectomy-specific complications prompt almost half of in-hospital mortalities after pancreatoduodenectomy, with rather long intervals for interventions to prevent failure to rescue. In contrast, visceral vasculature-related events and cardiopulmonary complications dominate early in-hospital mortalities with short intervals until mortality, demanding rigorous management of such events or preoperative conditioning. These data externally validate a previous high-volume initiative and highlight distinct windows of opportunity to optimize perioperative safety., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)