David Kessel

Subclavian Stents and Stent-Grafts: Cause for Concern?

Purpose: To report cases of stent and stent-graft fracture in the subclavian vessels. Methods and Results: Three patients with self-expanding stents of 3 different types in 1 subclavian artery and 2 subclavian veins presented with recurrent symptoms 6 months to 2 years after stenting. All devices showed signs of compression with stent fracture. The covered stent in the subclavian artery was excised. Of the 2 venous patients, 1 was treated with first rib resection and the other refused further treatment. Conclusions: The subclavian vessels are prone to flexion during movement, and the vessels may be compressed by external structures, including the clavicle and first rib. Stents that have not been designed to withstand these forces may be damaged.

Surgery versus thrombolysis for acute limb ischaemia: initial management.

BACKGROUNDnPeripheral arterial thrombolysis has become established as a useful adjunct in the management of peripheral arterial ischaemia. Much has been learnt about indications, risks and benefits using this technique, although data from randomised controlled studies is not extensive. The optimal initial management of the acutely ischaemic leg needs to be determined.nnnOBJECTIVESnTo determine if surgery or thrombolysis is the preferred option in the initial treatment of acute limb ischaemia.nnnSEARCH STRATEGYnThe search strategy was that adopted by the Cochrane Review Group on Peripheral Vascular Diseases. Additionally, reference lists of papers resulting from this search were reviewed.nnnSELECTION CRITERIAnAll randomised studies comparing thrombolysis and surgery in the management of acute limb ischaemia.nnnDATA COLLECTION AND ANALYSISnTrial quality was assessed and data were extracted independently by all three reviewers.nnnMAIN RESULTSnPatients with acute lesions of less than seven days duration had a significantly increased survival at one year for patients having thrombolysis, compared to those undergoing initial surgery [84% v 58%, p=0.01; Odds ratio (95% CI) 0.28 (0.13,0.63)] largely associated with a reduced level of in-hospital cardio-pulmonary complications (Ouriel 1994). Lesions less than 14 days duration fared better with initial lysis with a reduced amputation and reduced death rate at six months [15.3% v 37.5%; p=0.001; Odds ratio (95%CI) 0.29 (0.12,0.72)] (STILE 1994), compared to initial surgery. Analysis of the same trial at one year however revealed that native vessel thromboses had a more favourable outcome with initial surgery, largely due to continuing ischaemia in the lytic group [64% v 35%; p<0.0001; Odds ratio (95%CI) 3.26(1.96,5.52)] (Weaver 1996). Bypass graft thromboses less than 14 days old treated with initial thrombolysis were shown to have a reduced amputation rate (15% v 47%; p=0.05). However, overall, one year results revealed that thrombolysis of thrombosed grafts was associated with a higher level of continued ischaemia [73% v 50%; P=0.010; Odds ratio (95%CI) 2.72(1.27,5.80)] (Comerota 1996).nnnREVIEWERS CONCLUSIONSnA universal initial treatment with either surgery or thrombolysis cannot be advocated on the available evidence. There is no overall difference in limb salvage or death at one year between initial surgery and initial thrombolysis. Thrombolysis may however be associated with a higher risk of ongoing limb ischaemia, and a higher overall risk of haemorrhagic complications including stroke. The higher risk of complications needs to be balanced against the risks of surgery in the individual patient.

Surgery versus thrombolysis for initial management of acute limb ischaemia.

BACKGROUNDnPeripheral arterial thrombolysis is technique used in the management of peripheral arterial ischaemia. Much is known about the indications, risks and benefits of thrombolysis. However, it is not known whether thrombolysis works better than surgery in the initial treatment of acute limb ischaemia.nnnOBJECTIVESnTo determine the preferred initial treatment, surgery or thrombolysis, for acute limb ischaemia.nnnSEARCH METHODSnFor this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched March 2013) and CENTRAL (2013, Issue 2).nnnSELECTION CRITERIAnAll randomised studies comparing thrombolysis and surgery for the initial treatment of acute limb ischaemia.nnnDATA COLLECTION AND ANALYSISnEach author independently assessed trial quality and extracted data. Agreement was reached by consensus.nnnMAIN RESULTSnFive trials with a total of 1283 participants were included. There was no significant difference in limb salvage or death at 30 days, six months or one year between initial surgery and initial thrombolysis. However, stroke was significantly more frequent at 30 days in thrombolysis participants (1.3%) compared to surgery participants (0%) (Odds ratio (OR) 6.41; 95% confidence interval (CI) 1.57 to 26.22). Major haemorrhage was more likely at 30 days in thrombolysis participants (8.8%) compared to surgery participants (3.3%) (OR 2.80; 95% CI 1.70 to 4.60); and distal embolization was more likely at 30 days in thrombolysis participants (12.4%) compared to surgery participants (0%) (OR 8.35; 95% CI 4.47 to 15.58).Participants treated by initial thrombolysis underwent a less severe degree of intervention (OR 5.37; 95% CI 3.99 to 7.22) and displayed equivalent overall survival compared to initial surgery (OR 0.87; 95% CI 0.61 to 1.25).nnnAUTHORS CONCLUSIONSnUniversal initial treatment with either surgery or thrombolysis cannot be advocated on the available evidence. There is no overall difference in limb salvage or death at one year between initial surgery and initial thrombolysis. Thrombolysis may be associated with a higher risk of ongoing limb ischaemia and haemorrhagic complications including stroke. The higher risk of complications must be balanced against risks of surgery in each person.

Hepatic artery pseudoaneurysm after liver transplantation: treatment with percutaneous thrombin injection.

Pseudoaneurysms of the hepatic artery are a rare complication of liver transplantation. Early diagnosis and treatment are essential to avoid life-threatening hemorrhage. Conventional treatment consists of surgical resection and vascular reconstruction or transarterial coil embolization. More recently, percutaneous thrombin injection has been successfully used in the treatment of femoral artery pseudoaneurysms. We describe a 70-year-old woman who had a hepatic artery pseudoaneurysm after orthotopic liver transplantation, which was successfully treated by percutaneous thrombin injection.

Fibrinolytic agents for peripheral arterial occlusion

BACKGROUNDnPeripheral arterial thrombolysis is used in the management of peripheral arterial ischaemia. Streptokinase was originally used but safety concerns led to a search for other agents. Urokinase and recombinant tissue plasminogen activator (rt-PA) have increasingly become established as first line agents for peripheral arterial thrombolysis. Potential advantages of these agents include improved safety, greater efficacy and a more rapid response. Recently drugs such as pro-urokinase, recombinant staphylokinase and alfimperase have been introduced. This is an update of a review first published in 2010.nnnOBJECTIVESnTo determine which fibrinolytic agents are most effective in peripheral arterial ischaemia.nnnSEARCH METHODSnFor this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator (TSC) searched the Specialised Register (last searched March 2013) and CENTRAL (2013, Issue 3) for randomised controlled trials (RCTs) comparing fibrinolytic agents to treat peripheral arterial ischaemia.nnnSELECTION CRITERIAnRCTs comparing fibrinolytic agents to treat peripheral arterial occlusion.nnnDATA COLLECTION AND ANALYSISnData were analysed for the outcomes vessel patency, time to lysis, limb salvage, amputation, death, complications including major haemorrhage, stroke, and distal embolization.nnnMAIN RESULTSnFive RCTs involving a total of 687 participants with a range of clinical indications were included. No new studies were included in this update. In one three-pronged study, vessel patency was greater with intra-arterial recombinant tissue plasminogen activator (rt-PA) than with intra-arterial streptokinase (P < 0.04) or intravenous rt-PA (P < 0.01). In participants with peripheral arterial occlusion there was no statistically significant difference in limb salvage at 30 days with either urokinase or rt-PA, though this may reflect the small numbers in the studies. Incidences of haemorrhagic complications varied with fibrinolytic regime but there was no statistically significant difference between intra-arterial urokinase and intra-arterial rt-PA. In the three-pronged study intravenous rt-PA and intra-arterial streptokinase were associated with a significantly higher risk of haemorrhagic complications than with intra-arterial rt-PA (P < 0.05).nnnAUTHORS CONCLUSIONSnThere is some evidence to suggest that intra-arterial rt-PA is more effective than intra-arterial streptokinase or intravenous rt-PA in improving vessel patency in people with peripheral arterial occlusion. There was no evidence that rt-PA was more effective than urokinase for patients with peripheral arterial occlusion and some evidence that initial lysis may be more rapid with rt-PA, depending on the regime. Incidences of haemorrhagic complications were not statistically significantly greater with rt-PA than with other regimes. However, all of the findings come from small studies and a general paucity of results means that it is not possible to draw clear conclusions.

Endovascular Treatment of Visceral Aneurysms Associated with Pancreatitis and a Suggested Classification with Therapeutic Implications

PURPOSEnTo describe a 10-year experience of endovascular and percutaneous treatment of aneurysms and pseudoaneurysms complicating pancreatitis, and to analyze this experience and propose a classification based on computed tomography (CT) and angiographic findings that has therapeutic implications. This may reduce the rate of recurrent bleeding after surgery or endovascular treatment.nnnMATERIALS AND METHODSnTwenty-three patients with aneurysms or pseudoaneurysms associated with acute pancreatitis were treated by endovascular or percutaneous methods. All underwent CT and angiography. The early development of a simple classification based on the CT and angiographic findings was used to guide treatment decisions. In accordance with this classification, 19 patients were treated by primary coil embolization and four were treated by primary percutaneous thrombin injection.nnnRESULTSnAmong the 19 patients treated by primary coil embolization, there were two early recurrences of the pseudoaneurysm. All four patients treated by percutaneous thrombin injection exhibited late recurrences and were successfully treated by percutaneous thrombin injections. Twenty-one patients (91.3%) were alive at 6 months.nnnCONCLUSIONSnEndovascular and percutaneous treatment of aneurysms and pseudoaneurysms complicating pancreatitis is safe and effective and is associated with good outcomes, but careful follow-up is necessary. The decision of which treatment option is most appropriate can be made in accordance with a classification based on CT and angiographic appearance.

Endovascular stent-grafts for superficial femoral artery disease: results of 1-year follow-up.

PURPOSEnTo document a preliminary study to assess the deployment and outcomes of endoluminal stent grafting in the superficial femoral artery (SFA) with use of a prototype device.nnnMATERIALS AND METHODSnTwenty patients with lifestyle-limiting intermittent claudication were selected for treatment with a balloon-mounted expansive polytetrafluoroethylene graft. All patients had angiographically proven SFA disease (median length, 17 cm) with normal arterial inflow and at least two calf vessels patent to the ankle. Follow-up was by means of ankle brachial pressure index (ABPI), duplex ultrasound, and angiography.nnnRESULTSnFourteen patients were successfully treated. Six patients were excluded: five by the study protocol and one because the procedure was a technical failure. ABPI rose from 0.6 before treatment to 1.0. The treated limbs became asymptomatic. Twelve-month primary, primary assisted, and secondary patency rates of treated patients were 29%, 50%, and 64%.nnnCONCLUSIONnEndovascular stent grafting of SFA lesions is technically feasible, but the patency rates obtained with this design are inferior to those obtained with conventional surgical bypass.

Hemorrhagic Complications After Whipple Surgery: Imaging and Radiologic Intervention

OBJECTIVEnThe aim of this pictorial essay is to illustrate the radiologic patterns, sites of bleeding, and vascular interventional techniques used in the management of postpancreatectomy hemorrhage.nnnCONCLUSIONnHemorrhagic complications occur in fewer than 10% of patients after Whipple pancreatoduodenectomy but account for as many as 38% of deaths. Bleeding typically occurs from the stump of the gastroduodenal artery, but other sites of bleeding are increasingly recognized.

CIRSE guidelines: quality improvement guidelines for endovascular treatment of traumatic hemorrhage.

This quality improvement guideline outlines the place of interventional radiology (IR) in trauma management and indicates how imaging and IR can be used in the context of hemorrhage in the severely injured patient, and when IR is appropriate and when it is contraindicated. Vascular injury may also lead to occlusion, and this will be discussed where relevant. There is no intention for this document to be proscriptive; CIRSE and the writing committee recognize that successful centres may practice differently. The intention is to indicate how to develop the multidisciplinary linkages and infrastructure required for successful integration of imaging and IR in the trauma pathway. It is hoped that this will help prepare the way for greater consensus in the adoption of imaging and intervention in the management of the critically injured patient. The information presented here reflects available evidence and draws on pathways already in clinical use. It is intended for local consideration and adaptation according to current and future resources. Recommendations for practice and quality improvement are indicated throughout, and a checklist for safe use of intervention in the management of traumatic hemorrhage is included. Wherever possible, levels of evidence and grades of recommendation are based on those proposed by Oxford Centre for Evidence-based Medicine. A fuller version of this document is available at the CIRSE Web site.

ImaGiNe Seldinger: First simulator for Seldinger technique and angiography training

In vascular interventional radiology, procedures generally start with the Seldinger technique to access the vasculature, using a needle through which a guidewire is inserted, followed by navigation of catheters within the vessels. Visual and tactile skills are learnt in a patient apprenticeship which is expensive and risky for patients. We propose a training alternative through a new virtual simulator supporting the Seldinger technique: ImaGiNe (imaging guided interventional needle) Seldinger. It is composed of two workstations: (1) a simulated pulse is palpated, in an immersive environment, to guide needle puncture and (2) two haptic devices provide a novel interface where a needle can direct a guidewire and catheter within the vessel lumen, using virtual fluoroscopy. Different complexities are provided by 28 real patient datasets. The feel of the simulation is enhanced by replicating, with the haptics, real force and flexibility measurements. A preliminary validation study has demonstrated training effectiveness for skills transfer.