Vascular hand-arm vibration syndrome--magnetic resonance angiography.

The diagnosis of vascular hand-arm vibration syndrome (HAVS) requires consistent symptoms, photographic evidence of digital blanching and sufficient exposure to hand-transmitted vibration (HTV; A(8) > 2.5 m/s2). There is no reliable quantitative investigation for distinguishing HAVS from other causes of Raynaud's phenomenon and from normal individuals. Hypothenar and thenar hammer syndromes produce similar symptoms to HAVS but are difficult to diagnose clinically and may be confused with HAVS. Magnetic resonance angiography (MRA) is a safe and minimally invasive method of visualizing blood vessels. Three cases of vascular HAVS are described in which MRA revealed occlusions of the ulnar, radial and superficial palmar arteries. It is proposed that HTV was the cause of these occlusions, rather than blows to the hand unrelated to vibration, the assumed mechanism for the hammer syndromes. All three cases were advised not to expose their hands to HTV despite one of them being at Stockholm vascular stage 2 (early). MRA should be the investigation of choice for stage 2 vascular HAVS or vascular HAVS with unusual features or for a suspected hammer syndrome. The technique is however technically challenging and best done in specialist centres in collaboration with an occupational physician familiar with the examination of HAVS cases. Staging for HAVS should be developed to include anatomical arterial abnormalities as well as symptoms and signs of blanching. Workers with only one artery supplying a hand, or with only one palmar arch, may be at increased risk of progression and therefore should not be exposed to HTV irrespective of their Stockholm stage.

Randomized clinical trial of stents versus angioplasty for the treatment of iliac artery occlusions (STAG trial).

BACKGROUND: The management of total iliac artery occlusion is now undertaken routinely using percutaneous techniques but there are no controlled data to indicate whether either balloon angioplasty or stent placement is preferable. This was a multicentre randomized trial to assess whether stents confer any safety or efficacy advantage over balloon angioplasty for complete iliac artery occlusion. METHODS: Six participating centres recruited patients with symptoms of lower limb peripheral arterial disease due to iliac artery occlusion 8 cm or less in length. Patients were assigned randomly to either percutaneous transluminal angioplasty (PTA group) or primary stent placement (stent group) alone after the lesion had been traversed with a guidewire. RESULTS: There were 118 patients recruited to the study; six were excluded from the analysis owing to major protocol violations, leaving a total of 112 patients for analysis. Some 55 patients had PTA and 57 had a primary iliac stent. Technical success was achieved in 46 patients (84 per cent) in the PTA group and 56 (98 per cent) in the stent group (P = 0.007). There were 11 (20 per cent) major procedural complications after PTA compared with three (5 per cent) after primary stenting (P = 0.010). There were no significant differences in primary or secondary patency between the groups after 1 and 2 years. CONCLUSION: Primary stent placement for iliac artery occlusion increased technical success and reduced major procedural complications (predominantly distal embolization) compared with balloon angioplasty. REGISTRATION NUMBER: ISRCTN 48145465 (http://www.controlled-trials.com).

Effect of procedure volume on outcomes after iliac artery angioplasty and stenting.

BACKGROUND: Service reorganization to concentrate complex vascular services in hospitals with high caseload volume aims to reduce mortality and complication rates. The present study assessed the relationship between caseload volume and outcome for iliac artery angioplasty and stenting in England using a routinely available national data set (Hospital Episode Statistics, HES). METHODS: Routine administrative data for iliac artery angioplasty and stent procedures performed in England between 2007 and 2011 were analysed. Associations between centre volume and outcomes (death, complications and duration of hospital stay) were tested and compared for two methods of stratification (quartiles and quintiles) and two statistical tests (odds ratios and the Cochran-Armitage test for trend). Multivariable analysis was also performed. RESULTS: There were 23,308 episodes of care recorded in HES with Office of Population Censuses and Surveys Classification of Surgical Operations and Procedures, fourth revision, codes L54.1 or L54.4 corresponding to iliac artery intervention. There was a gradual increase year by year in number of procedures performed. Univariable and multivariable analysis showed no association between centre volume and either death or complications (multivariable odds ratio, OR 1.00, 95 per cent confidence interval 1.00 to 1.00) for elective and non-elective procedures. Age was associated with higher mortality and complication rates in elective procedures, and with mortality in non-elective procedures. The risk of death after elective iliac angioplasty or stenting was significantly higher in women (multivariable OR 4.98, 2.09 to 13.26). CONCLUSION: There was no association between the outcomes of endovascular iliac artery intervention and centre volume, but outcomes were significantly worse with increasing age and female sex.

United Kingdom carotid artery stent registry: short- and long-term outcomes.

BACKGROUND: Carotid artery stenting (CAS) has evolved to treat carotid artery disease with the intention of prevent stroke. The British Society of Interventional Radiologists developed a voluntary registry to monitor the practice of this novel procedure. We present the data from the United Kingdom (UK) CAS registry for short and long-term outcomes for symptomatic and asymptomatic carotid disease. METHODS: The UK CAS registry collected data from 1998 to 2010 from 31 hospitals across the UK for 1,154 patients. All interventions were enrolled in the registry for both asymptomatic and symptomatic patients. Initial entry forms were completed for each patient entered with data including indications, demographic data, CAS data (including stents and protection device details) and 30-day outcomes. Complications were documented. Follow-up data were collected at yearly intervals. RESULTS: Nine hundred fifty-three (83 %) symptomatic and 201 (17 %) asymptomatic patients were enrolled into the registry. The 30-day all stroke and death rates for symptomatic patients were 5.5 and 2.2 % for those with asymptomatic disease. The 30-day mortality rate was 1.7 % for symptomatic and 0.6 % for asymptomatic patients. For symptomatic patients undergoing CAS, the 7-year all-cause mortality rate was 22.2 % and for asymptomatic patients 18.1 %. The 7-year all-cause mortality and disabling stroke rates were 25.3 and 19.4 %, respectively. CONCLUSION: These data indicate that outside of the tight constraints of a randomised trial, CAS provides effective prophylaxis against stroke and death.

Long-term retrievability of IVC filters: should we abandon permanent devices?

Thromboembolic disease produces a considerable disease burden, with death from pulmonary embolism in the UK alone estimated at 30,000-40,000 per year. Whilst it is unproven whether filters actually improve longevity, the morbidity and mortality associated with thromboembolic disease in the presence of contraindications to anticoagulation is high. Thus complications associated with filter insertion, and whilst they remain in situ, must be balanced against the alternatives. Permanent filters remain in situ for the remainder of the patient's life and any complications from the filters are of significant concern. Filters that are not permanent are therefore attractive in these circumstances. Retrievable filters, to avoid or decrease long-term filter complications, appear to be a significant advance in the prevention of pulmonary embolism. In this review, we discuss the safety and effectiveness of both permanent and retrievable filters as well as the retrievability of retrievable inferior vena cava (IVC) filters, to explore whether the use of permanent IVC filters can be abandoned in favor of retrievable filters. Currently four types of retrievable filters are available: the Recovery filter (Bard Peripheral Vascular, Tempe, AZ, USA), the Günther Tulip filter (Cook, Bloomington, IN, USA), the OptEase Filter (Cordis, Roden, The Netherlands), and the ALN filter (ALN Implants Chirurgicaux, Ghisonaccia, France). Efficacy and safety data for retrievable filters are as yet based on small series, with a total number of fewer than 1,000 insertions, and follow-up is mostly short term. Current long-term data are poor and insufficient to warrant the long-term implantation of these devices into humans. The case of fractured wire from a Recovery filter that migrated to the heart causing pericardial tamponade requiring open heart surgery is a reminder that any new endovascular device remaining in situ in the long term may produce unexpected problems. We should also bear in mind that the data on permanent filters are much more robust, with reports on over 9,500 cases with follow-up of up to 8 years. The original implantation time of 10-14 days has been extended to more than 100 days as the mean implantation time with some of the filter types. Follow-up (preferably prospective) is necessary for all retrievable filters, whether or not they are retrieved. Until these data become available we should restrict ourselves to the present indications of permanent and retrievable filters. If long-term follow-up data on larger numbers of cases confirm the initial data that retrievable filters are as safe and effective as permanent filters, the use of the retrievable filters is likely to expand.

Safety of arch aortography for assessment of carotid arteries.

PURPOSE: To retrospectively review the safety of arch aortography and compare complication rates with published figures for selective catheter angiography. METHODS: The medical records of patients undergoing arch aortography over the last 3 years (n=311; 180 male, 131 female; mean+/-SD age 71.0+/-9.2 years, range 42-90 years) were retrospectively reviewed. Any peri-procedural (0-48 h) complications were recorded. A certified neurologist (MSR/GSV) classified all questionable neurological events. RESULTS: There were no focal neurological events or deaths (n=0; 0%; CI: 0-0.96%). Non-focal neurological events included mild disorientation (n=2; 0.6%; CI: 0.176-2.31) and unequal pupils (n=1; 0.3%; CI: 0.056-1.79%). Cardiovascular events included symptomatic hypotension (n=4; 1.3%; CI: 0.50-3.25%), angina (n=1; 0.3%; CI: 0.056-1.79%) and arrhythmia (n=4; 1.3%; CI: 0.50-3.25). There were 27 minor access site complications (8.7%; CI: 6.0-12.3). None of these complications extended hospital stay. None of the arch angiograms had to be followed by selective carotid angiography. CONCLUSION: Arch aortography appears to have a lower neurological complication rate than selective carotid angiography.

The benefits of combined anti-platelet treatment in carotid artery stenting.

OBJECTIVE: To assess the benefits of a combined anti-platelet regime of aspirin and clopidogrel in carotid artery stenting. METHODS: A randomised controlled trial was performed comparing aspirin and 24-h heparin with aspirin and clopidogrel for patients undergoing carotid artery stenting. Outcome measures included 30-day bleeding and neurological complications and 30-day stenosis rates. RESULTS: Bleeding complications (groin haematoma or excessive bleeding at the groin site) occurred in 17% of the heparin and 9% of the clopidogrel group (p=0.35; n.s). The neurological complication rate in the 24-h heparin group was 25% compared to 0% in the clopidogrel group (p=0.02). The 30-day 50-100% stenosis rates were 26% in the heparin group and 5% in the clopidogrel group (p=0.10; n.s). CONCLUSIONS: The dual anti-platelet regime has a significant impact on reducing adverse neurological outcomes without an additional increase in bleeding complications. This study was terminated prematurely due to an unacceptable level of complications in the heparin arm of the trial.

A multicentre evaluation of the Medtronic AVE Flexible Iliac Bridge Stent in the iliac arteries (the first study).

PURPOSE: To investigate the short term and 6 month outcomes of a recently introduced iliac stent (the Medtronic AVE Flexible Iliac Bridge Stent). METHOD: One hundred and sixteen patients, 122 limbs from 6 European sites with atherosclerotic occlusive disease were included if they either had a full occlusion or there was a residual gradient >10 mmHg following PTA. Clinical, haemodynamic and Duplex outcomes were recorded to 6 months. RESULTS: After stent placement there was no residual stenosis >30 and 8.1% of segments had a residual resting gradient of >10 mmHg. There were three local complications and three deaths at 30 days. Primary patency at 30 days and 6 months was 94.1 and 82.7%. Marked clinical improvement occurred in 87.6 and 86.2% at 30 days and 6 months. CONCLUSION: The Medtronic AVE iliac stent has good 30 day and 6 months outcomes supporting the effective use of this device in occlusive disease.

Is the endovascular treatment of carotid stenosis in high-risk patients really safer than carotid endarterectomy?

BACKGROUND: We assess the outcomes of patients who would have been considered at high-risk from carotid endarterectomy (CEA), who have undergone endovascular treatment. METHODS: High-risk patients were classed as those with occlusion of the contralateral internal carotid artery, recurrent stenosis following CEA, stenosis secondary to neck irradiation or treatment prior to coronary bypass surgery. RESULTS: 103 procedures fulfilled at least one inclusion criterion. 58.3% had symptomatic disease. The all stroke/death rate was 9.7%. The major disabling stroke/stroke-related death rate was 3.9%. 63 had a contralateral occlusion, 15 post-CEA, 17 post-radiation and 33 pre-coronary surgery. The major disabling stroke/stroke-related death rates for each subset were 4.8, 6.7, 0 and 0%, respectively. CONCLUSIONS: These results suggest that this category of patients is at high-risk of stroke regardless of method of carotid intervention.

Complications following carotid angioplasty and carotid stenting in patients with symptomatic carotid artery disease.

BACKGROUND: We review a single centre's experience of the endovascular treatment of carotid artery disease, present the 30-day and 1-year complication rates and assess whether changes in technique are associated with a change in clinical outcome. METHODS: Patients who underwent carotid angioplasty with or without stenting for symptomatic > or = 70% carotid artery stenosis secondary to atherosclerosis were included. 333 procedures were performed, i.e. angioplasty alone (86), stent without cerebral protection (150) and stent with cerebral protection (97). RESULTS: At 30 days, the total major disabling stroke and all death rate was 3.0%. For angioplasty alone, this was 2.3%, for stent without cerebral protection 4.0% and for stent with cerebral protection 2.1%. If non-stroke-related deaths were excluded, it was 2.3, 3.3 and 0%, respectively. After 30 days, the 1-year ipsilateral stroke rate was 0.8%. CONCLUSIONS: Carotid artery stenting, in particular with a cerebral protection device, is a safe alternative to carotid endarterectomy for the treatment of symptomatic high-grade carotid artery disease.

Effect of treatment of carotid artery stenosis on blood pressure: a comparison of hemodynamic disturbances after carotid endarterectomy and endovascular treatment.

BACKGROUND AND PURPOSE: Carotid intervention by carotid endarterectomy (CEA) or endovascular treatment may cause hemodynamic change. The immediate and long-term effects on blood pressure after these procedures were assessed. METHODS: Patients were randomized to CEA (n=49) or endovascular treatment (n=55) that comprised percutaneous transluminal angioplasty alone (n=31), balloon-expandable stent (n=13), or self-expandable stent (n=11). A baseline 24-hour ambulatory blood pressure recording was made before carotid intervention and repeated at 24 hours, 1 month, and 6 months after the procedure. RESULTS: In the first 24 hours after the procedure, episodes of hypotension occurred in 75% of the CEA group and 76% of the endovascular group; hypertension occurred in 11% and 13%, respectively. There was a significant fall in blood pressure at 1 hour after the procedure in both groups (24 and 16 mm Hg fall in CEA and endovascular groups, respectively), but this was only sustained in the endovascular group. The pattern of blood pressure response in the first 24 hours was significantly different (P<0.0001, ANCOVA). Systolic blood pressure was significantly lower at 1 and 6 months only in the surgical group (6 and 5 mm Hg fall, respectively). CONCLUSIONS: Both CEA and endovascular treatment have an effect on blood pressure stability, particularly within the first 24 hours after the procedure.

Mesenteric arterial ischaemia: diagnosis and therapeutic options.

Ischaemia of the bowel may arise from a number of causes affecting the arterial and venous compartments of the vascular tree. This article addresses the causes and consequences of arterial obstruction, which may compromise the supply of oxygenated blood to the bowel. These events may occur as an acute phenomenon, or they may present in a chronic fashion. The therapeutic options available to treat this condition are largely dependent on the mode of presentation and the amount of time that is available before irreversible damage occurs to the bowel integrity. In the acute phase, the viability of the bowel is in doubt, and this necessitates an open operative approach to assess the amount of bowel infarction which has already occurred. A variety of operative procedures are then available to limit this bowel loss and to secure the viability of the remaining bowel. In the more chronic phase there are alternative, less invasive procedures that may be appropriate for the patient, who may have suffered a prolonged period of undernourishment and dehydration. In such cases the immediate bowel viability is not in doubt, but the medium/long-term survival is compromised. Treatment options appropriate to each clinical scenario are discussed, along with the major technical issues associated with these treatments. A team approach to the most appropriate management plan is stressed, and the published outcomes reviewed.

Thoracic aortic stent grafts--early experience from two centres using commercially available devices.

OBJECTIVES: open surgical intervention for aneurysms of the distal arch and descending thoracic aorta is associated with high morbidity and mortality. Stent grafts offer an attractive alternative treatment for these aneurysms. The aim of this study was to assess the morbidity and mortality of endovascular treatment for these aneurysms with stent grafts. DESIGN, PATIENTS AND METHODS: a prospective observational study was performed of 37 consecutive patients treated from July 1997 to October 2000 (30 at Guy's and St. Thomas' and 7 at Sheffield). Indications included degenerative aneurysms (n=18), false aneurysm (5), acute dissection (4), aortic transection (4), aneurysm related to previous surgery for coarctation (3), chronic dissection (2) and traumatic dissection (1). Nineteen were performed as elective and 18 as non-elective procedures. RESULTS: three non-elective patients died in hospital (in-hospital and 30-day mortality 8%) and one suffered a stroke with spontaneous full recovery. No elective patient died. One patient with a persistent proximal endoleak required conversion to open repair at 6 weeks. Two patients with persistent flow into the sac at 24 h spontaneously thrombosed at subsequent 3 month follow-up. Two further patients developed new distal endoleaks at 3 months and required distal extension cuffs. One patient died at 28 months of aortic rupture. Serial CT scans had shown prolapse of the stent graft into the aneurysm sac and the patient died just before planned endovascular repair. No patient suffered paraplegia or renal failure. Intensive care facilities were only required for patients who needed them preoperatively. CONCLUSIONS: thoracic stent grafts can be performed with low morbidity and mortality. They offer a realistic alternative to open surgery. Long term follow up is required to assess their durability.

Unilateral leptomeningeal enhancement after carotid stent insertion detected by magnetic resonance imaging.

BACKGROUND AND PURPOSE: Percutaneous transluminal angioplasty combined with vascular stenting is currently being assessed in the treatment of patients with symptomatic, severe carotid stenosis. The immediate cerebral hemodynamic effects resulting from stenting are not fully understood. This article describes a novel finding: abnormal leptomeningeal enhancement after stenting shown by MRI. METHODS: Fourteen patients with symptomatic severe carotid bifurcation stenosis underwent MRI within 4 hours before and within 3 hours after attempted carotid stenting. Twelve patients were successfully stented. Part of the MR investigation consisted of the acquisition of T1-weighted images before and after administration of the contrast agent Gd-DTPA, both before and after the procedure. RESULTS: All 12 patients who underwent successful stenting did not have abnormal enhancement of the leptomeninges before stenting but developed unilateral enhancement following intervention but before the second injection of contrast agent. No contrast enhancement was detected in the 2 patients who had the angiographic procedure but were not stented. CONCLUSIONS: These findings suggest that abnormal changes to the leptomeningeal vasculature occur during carotid stenting which are not associated with sudden development of neurological symptoms. The anatomic distribution of the enhancement suggests that it is a consequence of the sudden change in brain hemodynamics secondary to the improvement in carotid flow after stenting.

Stenting in peripheral vascular disease.

Metallic stents have made an enormous impact on the percutaneous treatment of arterial and venous disease, allowing a range of lesions to be treated using this minimally invasive technique which was not possible previously. This article details the range of stents which are available and how these have revolutionized the treatment of vascular disease.

The treatment of aortoiliac occlusions by endovascular stenting with or without adjuvant femorofemoral crossover grafting.

We present four consecutive patients in whom we have used a combination of vascular and endovascular techniques in order to revascularise ischaemic legs caused by extensive aortoiliac occlusions. We believe that the techniques presented offer a viable alternative to more conventional surgical approaches in such cases.