Lars Norgren

Measurement and Interpretation of the Ankle-Brachial Index A Scientific Statement From the American Heart Association

Measurement and interpretation of the ankle-brachial index : a scientific statement from the Ammerican Heart Association

ESVS Guidelines. Invasive Treatment for Carotid Stenosis: Indications, Techniques

The European Society for Vascular Surgery brought together a group of experts in the field of carotid artery disease to produce updated guidelines for the invasive treatment of carotid disease. The recommendations were rated according to the level of evidence. Carotid endarterectomy (CEA) is recommended in symptomatic patients with >50% stenosis if the perioperative stroke/death rate is <6% [A], preferably within 2 weeks of the patients last symptoms [A]. CEA is also recommended in asymptomatic men <75 years old with 70-99% stenosis if the perioperative stroke/death risk is <3% [A]. The benefit from CEA in asymptomatic women is significantly less than in men [A]. CEA should therefore be considered only in younger, fit women [A]. Carotid patch angioplasty is preferable to primary closure [A]. Aspirin at a dose of 75-325 mg daily and statins should be given before, during and following CEA. [A] Carotid artery stenting (CAS) should be performed only in high-risk for CEA patients, in high-volume centres with documented low peri-operative stroke and death rates or inside a randomized controlled trial [C]. CAS should be performed under dual antiplatelet treatment with aspirin and clopidogrel [A]. Carotid protection devices are probably of benefit [C].

Effect of fibroblast growth factor NV1FGF on amputation and death: a randomised placebo-controlled trial of gene therapy in critical limb ischaemia

BACKGROUND Patients with critical limb ischaemia have a high rate of amputation and mortality. We tested the hypothesis that non-viral 1 fibroblast growth factor (NV1FGF) would improve amputation-free survival. METHODS In this phase 3 trial (EFC6145/TAMARIS), 525 patients with critical limb ischaemia unsuitable for revascularisation were enrolled from 171 sites in 30 countries. All had ischaemic ulcer in legs or minor skin gangrene and met haemodynamic criteria (ankle pressure <70 mm Hg or a toe pressure <50 mm Hg, or both, or a transcutaneous oxygen pressure <30 mm Hg on the treated leg). Patients were randomly assigned to either NV1FGF at 0·2 mg/mL or matching placebo (visually identical) in a 1:1 ratio. Randomisation was done with a central interactive voice response system by block size 4 and was stratified by diabetes status and country. Investigators, patients, and study teams were masked to treatment. Patients received eight intramuscular injections of their assigned treatment in the index leg on days 1, 15, 29, and 43. The primary endpoint was time to major amputation or death at 1 year analysed by intention to treat with a log-rank test using a multivariate Cox proportional hazard model. This trial is registered with ClinicalTrials.gov, number NCT00566657. FINDINGS 259 patients were assigned to NV1FGF and 266 to placebo. All 525 patients were analysed. The mean age was 70 years (range 50-92), 365 (70%) were men, 280 (53%) had diabetes, and 248 (47%) had a history of coronary artery disease. The primary endpoint or components of the primary did not differ between treatment groups, with major amputation or death in 86 patients (33%) in the placebo group, and 96 (36%) in the active group (hazard ratio 1·11, 95% CI 0·83-1·49; p=0·48). No significant safety issues were recorded. INTERPRETATION TAMARIS provided no evidence that NV1FGF is effective in reduction of amputation or death in patients with critical limb ischaemia. Thus, this group of patients remains a major therapeutic challenge for the clinician. FUNDING Sanofi-Aventis, Paris, France.

Venous thrombectomy for lliofemoral vein thrombosis — 10-year results of a prospective randomised study

Objectives: To study if venous thrombectomy prevents late post-thrombotic sequelae, venous obstruction reflux, and improves venous physiology following an acute iliofemoral venous thrombosis. Design: Prospective randomised controlled study. Material: Thirty patients returned for follow-up 10 years after an acute iliofemoral venous thrombosis initially treated with conventional anticoagulation treatment (medical group, n = 17) or with thrombectomy combined with a temporary arteriovenous fistula and anticoagulation (surgical group, n = 13). Clinical assessment, radionuclide angiography, duplex ultrasound and venous physiology tests were performed. Results: Leg swelling was recorded in 12 (71%) and leg ulcers in three (18%) of the medical patients and in, respectively, six (46%) and one (8%) of the surgical patients. The surgical patients had less severe sequelae (class 0–2). Radionuclide angiography demonstrated that the iliac vein was more commonly occluded following medical (59%) than following surgical (17%) treatment (p Conclusion: Venous thrombectomy improves venous patency and possibly reduces venous reflux and post-thrombotic sequelae as compared to anticoagulation treatment.

Ticagrelor versus Clopidogrel in Symptomatic Peripheral Artery Disease.

BACKGROUND Peripheral artery disease is considered to be a manifestation of systemic atherosclerosis with associated adverse cardiovascular and limb events. Data from previous trials have suggested that patients receiving clopidogrel monotherapy had a lower risk of cardiovascular events than those receiving aspirin. We wanted to compare clopidogrel with ticagrelor, a potent antiplatelet agent, in patients with peripheral artery disease. METHODS In this double‐blind, event‐driven trial, we randomly assigned 13,885 patients with symptomatic peripheral artery disease to receive monotherapy with ticagrelor (90 mg twice daily) or clopidogrel (75 mg once daily). Patients were eligible if they had an ankle–brachial index (ABI) of 0.80 or less or had undergone previous revascularization of the lower limbs. The primary efficacy end point was a composite of adjudicated cardiovascular death, myocardial infarction, or ischemic stroke. The primary safety end point was major bleeding. The median follow‐up was 30 months. RESULTS The median age of the patients was 66 years, and 72% were men; 43% were enrolled on the basis of the ABI and 57% on the basis of previous revascularization. The mean baseline ABI in all patients was 0.71, 76.6% of the patients had claudication, and 4.6% had critical limb ischemia. The primary efficacy end point occurred in 751 of 6930 patients (10.8%) receiving ticagrelor and in 740 of 6955 (10.6%) receiving clopidogrel (hazard ratio, 1.02; 95% confidence interval [CI], 0.92 to 1.13; P=0.65). In each group, acute limb ischemia occurred in 1.7% of the patients (hazard ratio, 1.03; 95% CI, 0.79 to 1.33; P=0.85) and major bleeding in 1.6% (hazard ratio, 1.10; 95% CI, 0.84 to 1.43; P=0.49). CONCLUSIONS In patients with symptomatic peripheral artery disease, ticagrelor was not shown to be superior to clopidogrel for the reduction of cardiovascular events. Major bleeding occurred at similar rates among the patients in the two trial groups. (Funded by AstraZeneca; EUCLID ClinicalTrials.gov number, NCT01732822.)

The Need for Clinical Trials of Endovascular Abdominal Aortic Aneurysm Stent-Graft Repair: The EUROSTAR Project

EUROSTAR(EUROpean collaborators on Stent-graft Techniques for abdominal aortic Aneurysm Repair) was established for the purpose of combining and studying data on endovascular abdominal aortic aneurysm (AAA) repair. EUROSTAR is independent of any commercial interest and has as its ultimate goal an independent, scientifically reliable assessment of endovascular AAA grafting. A standardized case record form is used for data collection and transmission, and the database is maintained in a central registry office. A comprehensive set of clinical, imaging, technical, and laboratory data obtained at initial admission and follow-up are recorded; these data are analyzed periodically and reports generated on the collated experience. As a first priority, an observational study without controls was initiated in July 1996 to address the issues of procedural safety, device durability, and long-term effect upon the aneurysms. Several ancillary studies have been initiated, including a “Retrieval and Analysis Study” for the evaluation of explanted devices. While a randomized study does not seem feasible at present, this may be organized at the appropriate time when the devices and techniques become more standardized.

First-generation aortic endografts: analysis of explanted Stentor devices from the EUROSTAR Registry.

Purpose: To examine the structure and healing characteristics of chronically implanted Stentor endografts that were explanted due to migration, endoleak, thrombosis, or aneurysm expansion. Methods: The devices were harvested following reoperation (n = 5) or autopsy (n = 1) with implantation times ranging from 13 to 53 months. Structural modifications to the metal components were examined using radiography, endoscopy, and magnetic resonance imaging (MRI). Specimens taken from components of the modular stent-grafts were examined histologically and with scanning electron microscopy (SEM) to assess healing behavior. Physical and chemical stability of the nitinol wires and woven polyester graft material was evaluated using SEM and electron spectroscopy for chemical analysis. Results: Although the endografts were retrieved for a variety of reasons, they exhibited similar healing and structural modifications. The woven polyester sleeve showed evidence of yarn shifting and distortion, yarn damage, and filament breakage leading to the formation of openings in the fabric. The luminal surface endografts showed incomplete healing characterized by a poorly organized, nonadherent thrombotic matrix of variable thickness. Radiographic and endoscopic observations indicated that structural failure of the grafts, particularly in the main aortic component, was related to severe compaction and dislocation of the metallic frame due to suture breaks. Corrosion marks were observed on some nitinol wires in all devices. Chemical analysis and ion bombardment of the nitinol wires revealed that the surface concentrations of titanium and nickel were not homogenous. The first layer was composed of carbon or organic elements, followed by a stratum of highly oxidized titanium with a low nickel concentration; the titanium-nickel alloy lay beneath these layers. Conclusions: Although the materials selected for construction of endovascular grafts appears judicious, the assembly of these biomaterials into various interrelated structures within the device requires further improvement.

Enoxaparin effect depends on body-weight and current doses may be inadequate in obese patients.

Venous thromboembolism is a significant cause of postoperative morbidity and mortality1. Risk factors include orthopaedic surgery, malignancy and obesity2. Low molecular weight heparin (LMWH) dominates for prophylaxis in general surgery3, and is usually given in a standard fixed dose; a higher dose is often suggested in high-risk situations. A study from the Mayo Clinic showed that of 32 cases of fatal pulmonary embolism after routine surgery, 16 had occurred in patients who were morbidly obese4. A survey among North American bariatric surgeons revealed that 48 per cent had personal experience of a patient with fatal thromboembolism. Fewer than 5 per cent chose not to use routine thromboprophylaxis5. The efficacy of LMWH in preventing clinically significant thromboembolic events has not been specifically studied in obese patients. Given the relative rarity of these events, such a study would require a large number of patients, and is unlikely ever to be performed. The effect of a given dose of enoxaparin can be monitored by measuring the plasma level of antifactor Xa (anti-Xa), which is thought to correlate with the antithrombotic effect, as well as with the risk of excessive bleeding6. The aim of the present study was to relate the anti-Xa activity to body-weight after injection of LMWH.

An Update on Methods for Revascularization and Expansion of the TASC Lesion Classification to Include Below-the-Knee Arteries: A Supplement to the Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC II).

The Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC) guidelines were last updated in 2007 (TASC II) and represented the collaboration of international vascular specialties involved in the management of patients with peripheral arterial disease (PAD). Since the publication of TASC II, there have been innovations in endovascular revascularization strategies for patients with PAD. The intent of this publication is to provide a complete anatomic lower limb TASC lesion classification, including the infrapopliteal segment, and an updated literature review of new endovascular techniques and practice patterns employed by vascular specialists today.

Endovascular treatment of ruptured abdominal aortic aneurysms: a shift of the paradigm?

Purpose: To compare endovascular aneurysm repair (EVAR) of ruptured abdominal aortic aneurysms (rAAA) to the results with open surgery. Methods: Between May 2001 and January 2004, 50 patients were diagnosed with rAAA. Fifteen (30%) patients (14 men; median age 73 years, range 58–85) underwent EVAR, while 26 (52%) patients (23 men; median age 75 years, range 60–84) had open surgery. Nine (18%) patients (5 men; median age 86 years, range 77–91) were not operated upon. Circulatory shock was defined as systolic blood pressure < 80 mmHg. Mortality was defined as death within 30 days after operation; in cases where hospital stay exceeded 30 days, in-hospital mortality was registered. Five risk factors (age >76 years, loss of consciousness, hemoglobin < 90 g/L, creatinine >190 μmol/L, and electrocardiographic ischemia) were analyzed. Results: In the EVAR group, 93% (14/15) of the aneurysms were excluded from the blood-stream; there were 2 (13%) conversions: 1 intraoperatively for stent-graft migration and another owing to dissection prior to hospital discharge. Mortality after open surgery was 46% (12/26) versus 13% (2/15) in the EVAR group (p>0.05). Univariate analysis without considering variables other than mortality resulted in OR 5.4 (95% CI 0.9 to 58; p=0.07). Considering risk factors and shock, multivariate analysis resulted in OR 6.5 (95% CI 0.8 to 96; p=0.08). In the EVAR group, 60% (9/15) had complications; in the group with open surgery, the complication rate was 85% (22/26; p=0.13). Conclusions: It is possible to treat rAAA with EVAR. Hypotensive patients can, at least initially, be operated under local anesthesia to stabilize blood pressure utilizing a percutaneously inserted occlusion balloon. There was a trend in our study for reduced mortality and morbidity with EVAR, but further studies are required to conclude whether EVAR significantly increases survival and reduces complications.