Stent Graft Placement by Pseudoaneurysm of the Hepatic Arteries: Efficacy and Patency Rate in Follow-up

Purpose To investigate efficacy and patency status of stent graft implantation in the treatment of hepatic artery pseudoaneurysm. Materials and Methods A retrospective analysis of patients who had undergone endovascular treatment of hepatic artery pseudoaneurysms between 2011 and 2020 was performed. Medical records were examined to obtain patients’ surgical histories and to screen for active bleeding. Angiographic data on vascular access, target vessel, material used and technical success, defined as the exclusion of the pseudoaneurysm by means of a stent graft with sufficient control of bleeding, were collected. Vessel patency at follow-up CT was analyzed and classified as short-term (< 6 weeks), mid-term (between 6 weeks and 1 year), and long-term patency (> 1 year). In case of stent occlusion, collateralization and signs of hepatic hypoperfusion were examined. Results In total, 30 patients were included and of these, 25 and 5 had undergone stent graft implantation and coiling, respectively. In patients with implanted stent grafts, technical success was achieved in 23/25 patients (92%). Follow-up CT scans were available in 16 patients, showing stent graft patency in 9/16 patients (56%). Short-term, mid-term, and long-term short-term stent patency was found in 81% (13/16), 40% (4/10), and 50% (2/4). In patients with stent graft occlusion, 86% (6/7) exhibited maintenance of arterial liver perfusion via collaterals and 14% (1/7) exhibited liver abscess during follow-up. Conclusion Stent graft provides an effective treatment for hepatic artery pseudoaneurysms. Even though patency rates decreased as a function of time, stent occlusion was mainly asymptomatic due to sufficient collateralization.

EP.WE.46Stentolith as an uncommon complication of loss to follow up after endoscopic biliary stenting

Introduction Endoscopic biliary stenting is a common procedure, with indications from malignant obstruction to benign stone disease. We discuss a patient who re-presented after endoscopic stenting having been lost to follow up, with a large ‘stentolith’ requiring open CBD exploration. Case Presentation A 56-year-old female presented in 2013 with obstructive jaundice and a 2-week history of abdominal pain. She was a smoker, but otherwise had no past medical, surgical, or relevant family history. After initial workup, ERCP with sphincterotomy and pigtail stent placement was performed with interval laparoscopic cholecystectomy in 2014. Post-operative follow up was not arranged, the patient subsequently re-presented in 2020 with fatigue. MRCP confirmed a proximal CBD stone and linear artefact. Open exploration facilitated removal of the stone-stent complex. Discussion Complications of stenting include cholangitis, stent occlusion and migration. Stenting for failed biliary stone extraction is considered a temporary measure, with removal or exchange at three months. However, patients may be lost to follow up and return with non-specific symptoms. A rare cause is de novo formation of a gallstone calculus encasing the stent, a phenomenon termed “stentolith”. Proposed pathophysiology is through promotion of bacterial proliferation by the stent, with biofilm formation and calcium bilirubinate precipitation. Variation in formation has been described, with plastic stents developing circumferential stones, due to potential space between the wall and stent. Conclusion This highlights the importance of robust inter-disciplinary working, careful patient follow up and implementation of a mandatory registry at all hospitals for stented patients.

Case Report: Double Micro-Guidewire Technique for Emergent Rescue of Proximal Stent Collapse During Recanalization of Nonacute Occlusion of Vertebral Artery

Cerebral arteries are usually tortuous, and in the treatment of cerebrovascular diseases with stenting, a stent deployed may be collapsed at one end, leading to reduced blood flow and subsequent stent occlusion. Immediate rescuing measures should be implemented to prevent severe ischemic events. In this case report, we present a case with V4 segment occlusion of the right vertebral artery treated with endovascular stent angioplasty. An Enterprise stent deployed at the occlusion segment was collapsed at the proximal end after withdrawal of the delivery system. Immediate rescuing measures were taken by navigating a micro-guidewire through the lateral stent mesh at the proximal end into the stent lumen followed by advancing a second micro-guidewire right through the reopened proximal stent end into the stent lumen for deployment of a supporting balloon-expandable Apollo stent to prevent stent collapse. Follow-up digital subtraction angiography 6 months later demonstrated patent stents and unobstructed blood flow.

106 Stentolith As an Uncommon Complication of Loss to Follow Up After Endoscopic Biliary Stenting

Introduction Endoscopic biliary stenting is a common procedure, with indications from malignant obstruction to benign stone disease. We discuss a patient who re-presented after endoscopic stenting having been lost to follow up, with a large ‘stentolith’ requiring open CBD exploration. Case Presentation A 56-year-old female presented in 2013 with obstructive jaundice and a 2-week history of abdominal pain. She was a smoker, but otherwise had no past medical, surgical, or relevant family history. After initial workup, ERCP with sphincterotomy and pigtail stent placement was performed with interval laparoscopic cholecystectomy in 2014. Post-operative follow up was not arranged, and the patient subsequently re-presented in 2020 with fatigue. MRCP confirmed a proximal CBD stone and linear artefact. Open exploration facilitated removal of the stone-stent complex. Discussion Complications of stenting include cholangitis, stent occlusion and migration [2]. Stenting for failed biliary stone extraction is considered a temporary measure, with removal or exchange at three months (1). However, patients may be lost to follow up and return with non-specific symptoms. A rare cause is de novo formation of a gallstone calculus encasing the stent, a phenomenon termed “stentolith” [4]. Proposed pathophysiology is through promotion of bacterial proliferation by the stent, with biofilm formation and calcium bilirubinate precipitation [6]. Variation in formation has been described, with plastic stents developing circumferential stones [12-25], due to potential space between the wall and stent. Conclusions This highlights the importance of robust inter-disciplinary working; careful patient follows up and implementation of a mandatory registry at all hospitals for stented patients.