Bryan D. Petersen

Gianturco-Rösch expandable Z-stents in the treatment of superior vena cava syndrome.

Gianturco-Rösch expandable Z-stents were used in 22 patients with superior vena cava syndrome (SVCS). Stents were placed in all patients in the SVC and in 17 patients, also into the innominate veins. Stent placement resulted in complete relief of symptoms in all patients. Twenty-one patients had no SVCS recurrence from 1 to 16 months, to their death, or to the present time. SVCS recurred only in 1 patient 9 months after stent placement due to tumor ingrowth and secondary thrombosis. Based on ours and on other reported experiences, expandable metallic stents are effective devices for treatment of the SVCS which is difficult to manage by other means.

Primary Stenting of Subclavian and Innominate Artery Occlusive Disease: A Single Center’s Experience

Purpose: To review immediate and midterm results of primary stenting for innominate and subclavian artery occlusive lesions.Methods: Retrospective data were collected from 48 consecutive symptomatic patients (27 men and 21 women, median age 64 years) having 49 subclavian and innominate artery lesions treated with stenting. Of the patients 52% had concomitant ischemic heart disease, and 30% had carotid and/or vertebral artery disease. Indication for treatment was vertebrobasilar insufficiency (VBI) in 16.6% of the patients; upper limb ischemia (ULI) in 31.3%; VBI and ULI in 12.5%; transient ischemic attack in 16.7%; angina in 12.5% before or after left internal mammary artery–to–coronary artery bypass grafting; and leg claudication in 10.4% before or after axillofemoral bypass grafting. Balloon-expandable stents were used in 44 lesions and self-expandable stents in 5 lesions. In total, 53 stents were placed in 48 patients.Results: Technical success was 96%, and clinical success 94%. We encountered four complications (two puncture site hematomas, one distal hand embolization and one transient cerebral ischemia). Two patients died within 30 days from other causes, and seven patients were lost to follow-up. Mean follow-up time was 16.7 months (range 0.3 to 68.2). Five patients had recurrent lesions treated by surgical (n = 2) or endovascular (n = 3) means. Cumulative primary patency rate was 91.7% and 77% at 12 and 24 months, respectively. Cumulative secondary patency rate was 96.5% and 91.7% at 12 and 24 months, respectively.Conclusion: Stenting of subclavian and innominate artery lesions resulted in immediate resolution of patients’ symptoms with durable midterm effect and few complications in a larger patient group with serious comorbid conditions.

Stent-Grafts for Revision of TIPS Stenoses and Occlusions: A Clinical Pilot Study

PURPOSE To assess the clinical and technical results of stent-graft placement for revision of transjugular intrahepatic portosystemic shunt (TIPS) stenoses and occlusions. MATERIALS AND METHODS Six patients who developed recurrent TIPS stenosis or occlusion of the parenchymal tract underwent shunt revision with use of polytetrafluoroethylene (PTFE) stent-grafts anchored at both ends by Z stents and centrally supported by Wallstents. RESULTS Before graft placement, mean primary patency was 50 days (range, 9-100 days). Patients underwent one to eight revisions with angioplasty or stent placement (mean, 3.2). Three patients had biliary-TIPS fistulas documented with use of a prototype double occlusion balloon catheter. Stent-grafts were successfully placed within the obstructed shunt, creating an excellent lumen in all cases. The portosystemic gradient was decreased from a mean of 24.3 mm Hg (range, 12-35 mm Hg) to a mean of 10.3 mm Hg (range, 7-16 mm Hg). Five of six patients were asymptomatic and no complications occurred (median clinical follow-up, 331 days). One patient died of pre-existing multi-organ system failure. The duration of primary patency after stent-grafting was improved (mean, 229 days; range, 27-324 days) and the difference approached statistical significance despite the small sample size (P = .056, paired t test). Three patients remained primarily patent at a mean venographic follow-up of 315 days. One shunt occluded at 1 month from residual thrombus in the portal vein, and one stenosis occurred that was secondary to misplacement of the original stent-graft. Patency was re-established in each of these patients. CONCLUSION PTFE covered stent-grafts are effective for shunt revision in patients with tract stenosis or occlusion and appear to improve TIPS patency.

Treatment of Malignant Esophageal Obstructions with Covered Metallic Z Stents: Long-term Results in 52 Patients☆

PURPOSE To prospectively evaluate the clinical efficacy of silicone-covered Gianturco-Rösch self-expandable Z (GRZ) stents in the treatment of malignant esophageal obstruction. PATIENTS AND METHODS GRZ stents were placed in 52 patients (39 men, 13 women) with severe dysphagia due to high-grade malignant esophageal obstruction. RESULTS Stent placement was technically successful, and immediate relief of dysphagia was achieved in 50 of 52 patients (96%), with long-term relief in 47 patients (90%). Fifty-one patients (98%) died during follow-up (range, 1 week to 33 months; mean, 4.3 months). Late complications were most prevalent and included stent migration (n = 5), food impaction (n = 2), chest pain (n = 2), membrane disruption with tumor ingrowth (n = 1), granulomatous reaction above the stent (n = 1), esophageal perforation with mediastinitis (n = 1), and upper gastrointestinal hemorrhage (n = 4). Twelve complications were easily managed with medical, endoscopic, or radiologic intervention. Four deaths may have been related to stent placement (early mortality rate, 7.7%). CONCLUSION GRZ stents provide relatively safe and effective long-term palliation in patients with severe, malignant esophageal obstruction.

Dural venous sinus angioplasty and stenting for the treatment of idiopathic intracranial hypertension

Background Lumboperitoneal shunt (LPS), ventriculoperitoneal shunt (VPS) and optic nerve sheath fenestration (ONSF) are accepted surgical therapies for medically refractory idiopathic intracranial hypertension (IIH). In the subset of patients with IIH and venous sinus stenosis, dural venous sinus stenting has emerged as an alternative surgical approach. Methods All cases of dural stents for IIH at our institution were retrospectively reviewed. Eligibility criteria included medically refractory IIH with documented papilledema and dural venous sinus stenosis of the dominant venous outflow system (gradient ≥10 mm Hg). Results Fifteen cases (all women) of mean age 34 years were identified. All had failed medical therapy and six had failed surgical intervention. Technical success was achieved in all patients without major periprocedural complications. The mean preprocedural gradient across the venous stenosis was reduced from 24 mm Hg before the procedure to 4 mm Hg after the procedure. Headache resolved or improved in 10 patients. Papilledema resolved in all patients and visual acuity stabilized or improved in 14 patients. There were no instances of restenosis among the 14 patients with follow-up imaging. Conclusion In this small case series, dural sinus stenting for IIH was performed safely with a high degree of technical success and with excellent clinical outcomes. These results suggest that angioplasty and stenting for the treatment of medically refractory IIH in patients with dural sinus stenosis warrants further investigation as an alternative to LPS, VPS and ONSF.

Intravascular Ultrasound-guided Direct Intrahepatic Portacaval Shunt: Description of Technique and Technical Refinements

PURPOSE This is a prospective study designed to demonstrate the safety and feasibility of creating a direct inferior vena cava (IVC)-to-portal vein shunt with use of a new type of intravascular ultrasound (IVUS) to guide the puncture and completing the shunt with the use of a polytetrafluoroethylene (PTFE)-covered stent graft. MATERIALS AND METHODS IVC-to-portal vein shunts were created in 31 sequential patients for ascites (n = 31) or bleeding (n = 8). Transfemorally placed IVUS transducers were positioned in the IVC to guide the puncture from the IVC to the portal vein, which was performed from a transjugular approach with a modified Rosch-Uchida liver access set. A 9-MHz axial imaging IVUS system was used for the first 11 patients, and a variable 5-10-MHz sagittal IVUS imaging system was used for the next 20 patients. The shunts were completed with the use of single (n = 11) or overlapping (n = 20) PTFE-covered Palmaz stent-grafts, deployed primarily at a diameter of 8 mm. Patients were followed clinically and with US, venography, and inspection at liver transplantation to establish 30-day patency rates. RESULTS All direct intrahepatic portacaval shunts (DIPSs) were created successfully. Both IVUS systems were able to adequately guide the portal vein puncture. Resolution and operator confidence were subjectively superior with the sagittal IVUS imaging system compared to the axial IVUS system. Two extrahepatic portal vein punctures occurred during the procedures. Both were controlled by the placement of sheaths and subsequent placement of stent-grafts. Both patients remained asymptomatic, although one required transfusion of blood products. The mean portosystemic gradient was reduced from 24 mm Hg before DIPS creation to 10 mm after DIPS creation. Embolization of varices was also performed in eight patients with history of recent gastrointestinal bleeding. Two patients died in the first week of acute liver failure. Two patients with hepatocellular carcinoma refused further follow-up. Of the 27 remaining patients, patency was demonstrated in all DIPS at 30 days by US, venography, or direct inspection at liver transplantation. CONCLUSIONS IVUS-guided direct IVC-to-portal vein shunts may be created successfully with minimal complications. The use of a stent-graft is recommended for this procedure. Modifications of current technique and IVUS systems are described.

Stent-Grafts for De Novo TIPS: Technique and Early Results

PURPOSE To evaluate the potential benefits of placing a polytetrafluoroethylene (PTFE)-covered stent-graft during initial creation of a transjugular intrahepatic portosystemic shunt (TIPS) in clinical practice. MATERIALS AND METHODS De novo TIPS were created with a PTFE stent-graft in four male and four female patients with symptomatic portal hypertension awaiting liver transplant. Their ages ranged from 35 to 62 (mean, 47) years. Patients were followed with TIPS ultrasound (US) and/or venography until liver transplantation or death; one remains under active study. Six recovered specimens underwent gross and microscopic evaluation. RESULTS All TIPS placements were successful. Six shunts were primarily patent, with a mean patency of 289 days, through completion of the study. Five were found to be patent at transplant and one was found to be patent at autopsy. Explant evaluation revealed a smooth, thin layer of neointima and exclusion of biliary secretions. Three patients developed a total of four stenoses (one tandem lesion) during follow-up, leading to revision in two patients. Mean primary and total patency in these patients was achieved after 279 and 463 days, respectively. A previously occult moderate stenosis was detected after explant in another patient. Only one (nonsignificant) stenosis clearly developed in an area covered by PTFE. CONCLUSION Placement of a de novo PTFE stent-graft during TIPS creation is feasible and may extend primary shunt patency. Appropriate positioning of the stent-graft is critical.

Intravascular US-guided direct intrahepatic portacaval shunt with a PTFE-covered stent-graft: feasibility study in swine and initial clinical results.

PURPOSE To determine the feasibility of the creation of a direct intrahepatic inferior vena cava (IVC)-to-portal-vein shunt with puncture guided by a transfemorally placed intravascular ultrasound (IVUS) probe and use of a polytetrafluoroethylene (PTFE)-covered stent-graft. MATERIALS AND METHODS In five swine, transjugular access was used to perform a direct puncture from the IVC to the portal vein with use of a modified Rosch-Uchida Portal Access set directed with real-time IVUS (9 MHz) introduced from a transfemoral venous approach. The direct intrahepatic portocaval shunt (DIPS) was then created with single or overlapping PTFE-covered Palmaz stents placed through a 10-F sheath and dilated to a diameter of 8 mm. Follow-up was performed with transhepatic portography at 2, 4, and 8 weeks. Animals were killed when shunts occluded or at the termination of the study at 8 weeks. Gross and microscopic histologic study was performed on sacrificed animals. A similar technique was used to create DIPS in five patients with intractable ascites, with follow-up by US and venography. RESULTS All experimental DIPS created in swine were created without complications. Portal vein punctures were achieved in four of five swine on the first or second pass of the needle. Follow-up transhepatic portography at 2 weeks demonstrated occlusion of two shunts, both explained by technical reasons at sacrifice. At 4 and 8 weeks, the remaining three shunts were patent on portography. Histology showed a thin neointimal lining with no significant tissue ingrowth or hyperplasia. Clinically, in five patients, successful puncture of the portal vein from the IVC was achieved in one to three passes. Creation of DIPS led to a reduction of mean portosystemic gradient from 18-29 mm Hg (mean, 24 mm Hg) to 9-10 mm Hg (mean, 9 mm Hg). One patient died of liver failure 2 days after creation of DIPS. The other four patients were doing well 2-15 months (mean, 8 months) after the procedure, with patency confirmed by US and venography. CONCLUSION Creation of DIPS is technically feasible, and the direct IVC-to-portal-vein puncture can be done accurately with real-time IVUS guidance. Further studies and longer follow-up are necessary to determine if the short length of the PTFE-covered stent-graft and avoidance of the hepatic vein will increase the long-term patency compared to standard transjugular intrahepatic portosystemic shunt creation.

Neuroform Stent-Assisted Embolization of Incidental Anterior Communicating Artery Aneurysms: Long-term Clinical and Angiographic Follow-up

BACKGROUND:Anterior communicating artery (A-comm) aneurysm is one of the most common intracranial aneurysms. Treatments include neurosurgical clipping or endovascular embolization. OBJECTIVE:To retrospectively examine the long-term results of Neuroform stent-assisted coil embolization of incidental A-comms, with a focus on stent-associated stenosis, long-term angiographic aneurysm occlusion outcome, delayed stent-related thromboembolus, subsequent subarachnoid hemorrhage from the treated aneurysm, and procedural complications. METHODS:Between January 7, 2003 and June 16, 2009, 44 Neuroform stents were placed as an adjunct to embolization of A-comms. Patient charts were reviewed retrospectively. Angiographic follow-up of at least 3 months (up to 6.5 years, mean 65 weeks) was available for 33 patients. Aneurysm occlusion success was determined using the Raymond classification for aneurysm remnants. RESULTS:Referencing the last angiogram in the follow-up course, complete occlusion, dog-ear residual, residual neck, and residual aneurysm were found in 24, 2, 3, and 4 patients, respectively. Stenosis (45% and asymptomatic) of the artery where the stent had been placed was found in 1 patient. One patient had delayed transient ischemic attack after dual antiplatelet therapy was stopped prematurely. Retreatment based on the presence of residual aneurysm was performed or recommended in 2 patients. In 2 patients with residual or recurrent aneurysm filling, their age or clinical condition did not warrant retreatment. CONCLUSION:Neuroform stent-assisted embolization provides long-term control of A-comms with a low incidence of aneurysm growth after treatment. The need for retreatment is uncommon, and retreatment is safe if performed. Subsequent bleeding from treated aneurysms was not observed in this study.

Inferior epigastric artery pseudoaneurysm: A complication of paracentesis

Two patients had inferior epigastric artery pseudoaneurysms after therapeutic paracentesis for ascites caused by portal hypertension. The first patient, a 62-year-old man, had a two-week history of left lower quadrant pain, tenderness, and nonpulsatile mass after a paracentesis for ascites. A left inferior epigastric artery pseudoaneurysm measuring 10 cm in diameter and 20 cm in length was diagnosed by means of Duplex ultrasound and arteriography. The patient was treated with percutaneous embolization, with successful thrombosis of the pseudoaneurysm. The second patient, a 33-year-old woman, had a six-week history of left lower quadrant pain, tenderness, and nonpulsatile mass after a paracentesis for ascites. Computerized tomography and arteriography showed a left inferior epigastric artery pseudoaneurysm, measuring 7 cm in diameter and 9 cm in length. The patient was treated with percutaneous embolization with successful thrombosis of the pseudoaneurysm. Both patients were discharged in good condition 2 days after embolization. Inferior epigastric artery pseudoaneurysm is a complication of paracentesis, and percutaneous embolization may be preferable to surgical repair in patients with chronic liver failure and portal hypertension.