Behavioural recovery after treatment for varicose veins.

BACKGROUND: The aim of this study was to assess behavioural recovery from the patient's perspective as a prespecified secondary outcome in a multicentre parallel-group randomized clinical trial comparing ultrasound-guided foam sclerotherapy (UGFS), endovenous laser ablation (EVLA) and surgery for the treatment of primary varicose veins. METHODS: Participants were recruited from 11 UK sites as part of the CLASS trial, a randomized trial of UGFS, EVLA or surgery for varicose veins. Patients were followed up 6 weeks after treatment and asked to complete the Behavioural Recovery After treatment for Varicose Veins (BRAVVO) questionnaire. This is a 15-item instrument that covers eight activity behaviours (tasks or actions an individual is capable of doing in an idealized situation) and seven participation behaviours (what the individual does in an everyday, real-world situation) that were identified to be important from the patient's perspective. RESULTS: A total of 798 participants were recruited. Both UGFS and EVLA resulted in a significantly quicker recovery compared with surgery for 13 of the 15 behaviours assessed. UGFS was superior to EVLA in terms of return to full-time work (hazard ratio 1·43, 95 per cent c.i. 1·11 to 1·85), looking after children (1·45, 1·04 to 2·02) and walks of short (1·48, 1·19 to 1·84) and longer (1·32, 1·05 to 1·66) duration. CONCLUSION: Both UGFS and EVLA resulted in more rapid recovery than surgery, and UGFS was superior to EVLA for one-quarter of the behaviours assessed. The BRAVVO questionnaire has the potential to provide important meaningful information to patients about their early recovery and what they may expect to be able to achieve after treatment.

Cost-effectiveness of ultrasound-guided foam sclerotherapy, endovenous laser ablation or surgery as treatment for primary varicose veins from the randomized CLASS trial.

BACKGROUND: The treatment of patients with varicose veins constitutes a considerable workload and financial burden to the National Health Service. This study aimed to assess the cost-effectiveness of ultrasound-guided foam sclerotherapy (UGFS) and endovenous laser ablation (EVLA) compared with conventional surgery as treatment for primary varicose veins. METHODS: Participant cost and utility data were collected alongside the UK CLASS multicentre randomized clinical trial, which compared EVLA, surgery and UGFS. Regression methods were used to estimate the effects of the alternative treatments on costs to the health service and quality-adjusted life-years (QALYs) at 6 months. A Markov model, incorporating available evidence on clinical recurrence rates, was developed to extrapolate the trial data over a 5-year time horizon. RESULTS: Compared with surgery at 6 months, UGFS and EVLA reduced mean costs to the health service by £655 and £160 respectively. When additional overhead costs associated with theatre use were included, these cost savings increased to £902 and £392 respectively. UGFS produced 0·005 fewer QALYs, whereas EVLA produced 0·011 additional QALYs. Extrapolating to 5 years, EVLA was associated with increased costs and QALYs compared with UGFS (costing £3640 per QALY gained), and generated a cost saving (£206-439) and QALY gain (0·078) compared with surgery. Applying a ceiling willingness-to-pay ratio of £20 000 per QALY gained, EVLA had the highest probability (78·7 per cent) of being cost-effective. CONCLUSION: The results suggest, for patients considered eligible for all three treatment options, that EVLA has the highest probability of being cost-effective at accepted thresholds of willingness to pay per QALY.

Comparison of fluorodeoxyglucose uptake in symptomatic carotid artery and stable femoral artery plaques.

BACKGROUND: Fluorine-18-labelled fluoroxdeoxyglucose (FDG) positron emission tomography (PET) has been used to evaluate atherosclerotic plaque metabolic activity, and through its uptake by macrophages is believed to have the potential to identify vulnerable plaques. The aims were to compare FDG uptake in carotid plaques from patients who had sustained a recent thromboembolic cerebrovascular event with that in femoral artery plaques from patients with leg ischaemia, and to correlate FDG uptake with the proportion of M1 and M2 macrophages present. METHODS: Consecutive patients who had carotid endarterectomy for symptomatic, significant carotid stenosis and patients with severe leg ischaemia and significant stenosis of the common femoral artery underwent FDG-PET and histological plaque analysis. The voxel with the greatest activity in the region of interest was calculated using the Patlak method over 60 min. Plaques were dual-stained for CD68, and M1 and M2 macrophage subsets. RESULTS: There were 29 carotid and 25 femoral artery plaques for study. The maximum dynamic uptake was similar in carotid compared with femoral plaques: median (range) 9·7 (7·1-12·2) versus 10·0 (7·4-16·6) respectively (P = 0·281). CD68 macrophage counts were significantly increased in carotid compared with femoral plaques (39·5 (33·9-50·1) versus 11·5 (7·7-21·3) respectively; P < 0·001), as was the proportion of M1 proinflammatory macrophages. The degree of carotid stenosis correlated with the maximum dynamic FDG uptake (rs = 0·48, P = 0·008). CONCLUSION: FDG uptake was no greater in symptomatic carotid plaques than in the less inflammatory femoral plaques. In patients on statin therapy. FDG uptake occurred in areas of significant arterial stenosis, irrespective of the degree of inflammation.

The Aberdeen varicose vein questionnaire, patient factors and referral for treatment.

OBJECTIVES: It has been suggested that the Aberdeen Varicose Vein Questionnaire (AVVQ) could be used to help inform a patient pathway for referral and treatment of varicose veins. We aimed to determine 1) which patient and vein characteristics affected the AVVQ score, and 2) whether scores differed between those who were and were not offered treatment. METHODS: Patients completed the AVVQ at the clinic prior to being seen. Treatment was offered to patients with symptoms, and duplex detected truncal incompetence by surgeons blinded to the score. RESULTS: A total of 228 consecutive patients completed the AVVQ: 199 were valid questionnaires. On multivariate analysis, factors associated with a worse quality of life were female gender (p = .034, 3.14 mean unit increase in AVVQ), and bilateral varicose veins (10.25 unit increase, p < .001). For patients with C2 disease, only the presence of bilateral veins was significant. Overall, the AVVQ score was higher in those patients offered treatment than in those who were not (mean 20.3 [SD = 9.9] vs. 17.3 [SD = 10.3], p = .023), which equates to a 2.74 unit increase. This was not significant in patients with C2 disease. CONCLUSION: It is unlikely that a threshold AVVQ score could be used to aid referral of patients with C2 disease. The distribution of veins (unilateral vs. bilateral) must be adjusted for when reporting AVVQ scores.

A meta-analysis of randomized trials comparing surgery versus endovascular therapy for thrombosed arteriovenous fistulas and grafts in hemodialysis.

PURPOSE: To carry out a systematic review of randomized trials comparing surgery vs. endovascular therapy for occluded fistulas and grafts. METHODS: All randomized trials which compared surgery and endovascular therapy for occluded fistulas and grafts were retrieved from 1990 onwards. The following search terms were used: "haemodialysis," "thrombosis," "arteriovenous fistula," "arteriovenous shunt," "end stage renal failure" on Medline and PubMed. The results of the pooled data were analysed by a fixed-effect model. RESULTS: There were no randomized trials comparing surgery vs. endovascular therapy for native fistulas and vein grafts. Six randomized studies reporting on 573 occluded grafts were identified. Technical success, need for access line and primary patency at 30 days were similar between the two groups (odds ratio [OR] 1.40, 95 % confidence interval [CI] 0.91-2.14; OR 0.77, 95 % CI 0.44-1.34; and OR 1.15, 95 % CI 0.79-1.68, respectively). There was no significant difference in morbidity at 30 days between groups (OR 1.12, 95 % CI 0.67-1.86). There were no statistical difference between the two groups for 1 year primary patency (OR 2.08, 95 % CI 0.97-4.45). Primary assisted patency at 1 year was better with surgery (OR 3.03, 95 % CI 1.12-8.18) in a single study. CONCLUSION: Comparable results to surgery have been achieved with endovascular techniques for occluded prosthetic grafts for dialysis access. Long-term data comparing the two groups were lacking. Further trials designed to encompass variation in methods are warranted in order to obtain the best available evidence particularly for native fistulas.

Macrophage subtypes in symptomatic carotid artery and femoral artery plaques.

OBJECTIVE: To compare differences in macrophage heterogeneity and morphological composition between atherosclerotic plaques obtained from recently symptomatic patients with carotid artery disease and femoral plaques from patients with severe limb ischemia. DESIGN: Experimental study. METHODS: Plaques were obtained from 32 patients undergoing carotid endarterectomy and 25 patients undergoing common femoral endarterectomy or lower limb bypass. Macrophages and T cell numbers were detected in plaque sections by immunohistochemistry and anti CD68 and CD3 antibodies. Dual staining for CD68 and M1- and M2-macrophage markers and morphometric analysis of hematoxylin and eosin stained plaque sections was performed. RESULTS: Carotid plaques had significantly increased percentage areas of confluent lipid and leukocytic infiltrates. In contrast, areas of fibroconnective tissue were significantly greater in femoral plaques and percentage areas of confluent calcification and collagen were elevated. Carotid artery plaques had greater numbers per plaque area of macrophages and T cells consistent with a more inflammatory phenotype. Proportions displaying M1-activation markers were significantly increased in the carotid compared to femoral plaques whereas femoral plaques displayed a greater proportion of M2-macrophages. CONCLUSION: Plaques from patients with recently symptomatic carotid disease have a predominance of M1-macrophages and higher lipid content than femoral plaques, consistent with a more unstable plaque.

Platelet activation, coagulation activation and C-reactive protein in simultaneous samples from the vascular access and peripheral veins of haemodialysis patients.

INTRODUCTION: Most studies of haemodialysis (HD) patients compare venous blood samples from controls with samples from the vascular access (VA) of HD patients. We hypothesised that VA samples may be more prothrombotic compared with venous samples. METHODS: Samples were taken simultaneously from the VA and the contralateral antecubital vein, from 26 patients immediately before HD. Platelet function was assessed by (1) flow cytometric measurement of P-selectin expression and fibrinogen binding (±ADP) and 2) Ultegra rapid platelet function assay. Plasma soluble P-selectin, von Willebrand factor antigen, high sensitivity C-reactive Protein (hs-CRP), thrombin-antithrombin III complex and D-dimer measured by ELISA. RESULTS: Thrombin receptor activating peptide-induced platelet aggregation (P < 0.001) and hs-CRP (P < 0.001) were higher in VA compared with venous samples. Unstimulated platelet fibrinogen binding (P = 0.016) and ADP-stimulated P-selectin expression (P = 0.008) were lower in VA compared with venous samples. The significant difference in hsCRP persisted when patients taking and not taking antiplatelet therapy were analysed separately, but platelet activation remained significantly different only in the nonantiplatelet group. CONCLUSION: There are statistically significant differences between sampling sites, although samples from the VA do not appear to be more pro-thrombotic. Future studies comparing HD patients with controls should ensure uniformity of sampling sites to prevent inaccurate conclusions being drawn.

N-terminal pro-B-type natriuretic peptide is an independent predictor of all-cause mortality and MACE after major vascular surgery in medium-term follow-up.

OBJECTIVE: Recent interest has focussed on the role of biomarkers to predict outcome in patients undergoing major vascular surgery. We wished to determine if pre- and postoperative N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) levels could predict all-cause mortality (ACM; primary aim) and major adverse cardiac event (MACE) (secondary aim) in the medium-term follow-up in patients who have undergone elective major vascular surgery. METHOD: Patients who underwent major elective vascular surgery (n = 136) were followed up for up to 2 years. ACM and first MACE episode were identified from the case notes and the patient management system database of the hospital intranet. RESULTS: One patient was lost to follow-up. In the mean follow-up of 654 days, 27 (20%) died and 23 (17%) patients suffered a MACE. Receiver operator curve (ROC) analysis showed that a pre-operative NT-pro-BNP level with a cut-off of 359 pg ml(-1) had a sensitivity and specificity of 73% each (area under the curve (AUC) 80%, p < 0.001) in predicting ACM and sensitivity of 74% and specificity of 71% (AUC 75%, p < 0.001) to detect a MACE. The overall 2-year survival rate was 84%, 93% in the <359 pg ml(-1) group and 68% in the ≥359 pg ml(-1) group (p < 0.001). Following multivariate analysis, pre-operative NT-pro-BNP at a value of ≥359 pg ml(-1) remained an independent predictor of ACM (odds ratio 3.6 (confidence interval (CI): 1.6-8.1), p = 0.002) Postoperative NT-pro-BNP was a predictor of mortality but not a MACE. CONCLUSION: This study has shown that pre-operative NT-pro-BNP is an independent predictor of ACM and MACE on medium-term follow-up.

Introducing endovenous laser therapy ablation to a national health service vascular surgical unit - the Aberdeen experience.

OBJECTIVES: To report early clinical outcomes and learning experience following the introduction of endovenous laser ablation (EVLA) to an NHS vascular unit. DESIGN: Prospective observational study. RESULTS: Between February 2006 and January 2008, 631 consecutive patients underwent EVLA to 704 refluxing truncal veins - 579 GSV, 119 SSV and 6 straight segments of anterior accessory GSV. 275/631 (44%) patients had local anaesthesia (LA) plus sedation, 237 (38%) had LA only and 119 (18%) had general anaesthesia. All were treated using the 810 nm diode laser. Adjuvant procedures on-table included foam sclerotherapy 129/704 (18%), multiple stab avulsions 53/704 (8%) and 3 limbs had both. Three-month follow-up with duplex examination is complete in 635/704 limbs (90%). Complete occlusion was noted in 610 veins (96%), 14 (2.2%) were partially occluded and 11 (1.7%) showed no occlusion. 193 (30%) of the 635 limbs seen at follow-up required further treatment for residual varicosities using foam sclerotherapy. There has been one non-fatal pulmonary embolus associated with EVLA and no other complications. CONCLUSIONS: EVLA is safe and technically effective. It has a defined learning curve requiring new operator skills which can be readily acquired.

The role of subintimal angioplasty in the management of arterial disease of the lower limb: the North-East of Scotland experience.

INTRODUCTION: The management of occlusive femoropopliteal disease continues to evolve and a definitive strategy remains to be defined. We examine the utility ofsubintimal angioplasty (SIA) in our institution. METHODS: A retrospective study with predefined end-points, including technical success and primary patency. RESULTS: 61 consecutive cases were identified (claudicants n=29 and critical ischaemia n=32). Sixty-four percent of occlusions were greater than 10 cm with poor run-off (60% with two vessels or less). Technical and physiological success was 95% and 79% respectively, with clinical improvement reported by 72%. At a mean follow-up of 20 months twelve-month primary patency (assessed clinically, with ABPI and selective duplex scanning) was 67% (subgroup analysis: claudicants 83%, criticals 53%, p=0.02) and morbidity 8% with no limb loss or procedure related mortality. CONCLUSION: SIA is an effective procedure for chronic lower limb ischaemia with acceptable outcome. Our experience correlates well with evidence in the current literature.

Platelet activation, myocardial ischemic events and postoperative non-response to aspirin in patients undergoing major vascular surgery.

OBJECTIVES: Myocardial ischemia is the leading cause of postoperative mortality and morbidity in patients undergoing major vascular surgery. Platelets have been implicated in the pathogenesis of acute thrombotic events. We hypothesized that platelet activity is increased following major vascular surgery and that this may predispose patients to myocardial ischemia. METHODS: Platelet function in 136 patients undergoing elective surgery for subcritical limb ischemia or infrarenal abdominal aortic aneurysm repair was assessed by P-selectin expression and fibrinogen binding with and without adenosine diphosphate (ADP) stimulation, and aggregation mediated by thrombin receptor-activating peptide and arachidonic acid (AA). Cardiac troponin-I (cTnI) was performed. RESULTS: P-selectin expression increased from days 1 to 3 after surgery [median increase from baseline on day 3: 53% (range: -28% to 212%, P < 0.01) for unstimulated and 12% (range: -9% to 45%, P < 0.01) for stimulated]. Fibrinogen binding increased in the immediate postoperative period [median increase from baseline: 34% (range: -46% to 155%, P < 0.05)] and decreased on postoperative day 3 (P < 0.05). ADP-stimulated fibrinogen binding increased on day1 (P < 0.05) and thereafter decreased. Platelet aggregation increased on days 1-5 (P < 0.05). Twenty-eight (21%) patients had a postoperative elevation (> 0.1 ng mL(-1)) of cTnI. They had significantly increased AA-stimulated platelet aggregation in the immediate postoperative period and on day 2 (P < 0.05), and non-response to aspirin (48% vs. 26%, P = 0.036). CONCLUSIONS: This study has shown increased platelet activity and the existence of non-response to aspirin following major vascular surgery. Patients with elevated postoperative cTnI had significantly increased AA-mediated platelet aggregation and a higher incidence of non-response to aspirin compared with patients who did not.

Utility of B-type natriuretic peptide in predicting perioperative cardiac events in patients undergoing major non-cardiac surgery.

BACKGROUND: B-type natriuretic peptide (BNP) levels predict cardiovascular risk in several settings. We hypothesized that they would identify individuals at increased risk of early cardiac complications after major non-cardiac surgery. The current study tests this hypothesis. METHODS: Two hundred and four patients undergoing major non-cardiac surgery were studied. The primary end-point was the development of acute myocardial injury [defined as cardiac troponin I (cTnI) level > 0.32 ng ml(-1)] or death in the 3 days after surgery. RESULTS: Preoperative BNP levels were raised in patients who died or suffered perioperative myocardial injury (median 52.2 vs 22.2 pg ml(-1), P = 0.01) and BNP predicted this outcome with an area under the receiver operating characteristic curve of 0.72 [95% confidence interval (CI) 0.59-0.86, P = 0.01]. A preoperative BNP value > 40 pg ml(-1) was associated with an increased risk of death or perioperative myocardial injury [odds ratio (OR) 6.8, 95% CI 1.8-25.9, P = 0.003], and remained independently predictive after correction for the Revised Cardiac Risk Index. Preoperative BNP levels were higher in patients who exhibited new onset atrial fibrillation or ST/T-wave changes on their postoperative ECG (median 50.5 vs 22.5 pg litre(-1), P = 0.01). They were also higher in patients who had either elevation of cTnI > 0.32 ng ml(-1) or postoperative ECG abnormalities (median 50.4 vs 21.5 pg ml(-1), P < 0.001). CONCLUSIONS: In the setting of major non-cardiac surgery, preoperative BNP levels are higher in patients who experience perioperative death and myocardial injury. Larger studies are required to confirm these data and to clarify what BNP levels may add to existing methods of risk stratification.

Completing the audit cycle: comparison of cardiac risk factor management in patients with intermittent claudication in two time periods.

AIM: The first line treatment of patients with intermittent claudication (IC) is to prolong life via cardiac risk factor management. We aimed to compare current standards of secondary prevention with those in a previously published audit. METHODS: Risk factor data was prospectively collated on 304 consecutive new referrals attending the claudication clinic over a 1-year period (2004/2005) and compared to the 104 patients assessed in 2000. RESULTS: In 2004/5 30%, (n=91) of patients did not have a diagnosis of IC confirmed (p<0.01). The use of antiplatelet therapy remained static at 73%. Statin therapy increased in 2004/5 (62% versus 38%, p<0.01) but blood pressure control remained poor with 65% failing to achieve the target levels. Smoking cessation therapy continues to be offered to a minority of patients and 17% of patients have previously undiagnosed diabetes in 2004/2005 (p-value 0.353). The number of patients who have been advised to increase physical activity significantly has fallen from 15% to 2% in the 2004/5 (p<0.01). CONCLUSIONS: Difficulties exist in diagnosing intermittent claudication in primary care and cardiac risk factor management continues to be sub-optimally managed.

Surgical revascularisation in patients with severe limb ischaemia induces a pro-thrombotic state.

Platelet and coagulation activation are implicated in the increased incidence of ischaemic events seen in patients with peripheral arterial disease. This study aimed to assess the effect of surgical revascularisation on platelet aggregation and coagulation in patients with severe limb ischaemia (SLI). Twenty-two patients had blood samples taken: prior to surgery, on reperfusion, 2, 24 and 48 h post-surgery. Platelet aggregation through COX-mediated and thrombin receptor activator peptide (TRAP)-stimulated GPIIb/IIIa pathways was measured by the Ultegra point of care system. Thrombin-antithrombin III Complex (TAT) and D-dimer were measured by ELISA. COX-mediated aggregation increased significantly at reperfusion and remained elevated at 24 h [median increase from baseline of 9% (range -16 to 33%) P = 0.011]. TRAP-stimulated aggregation increased significantly at reperfusion and remained elevated at 2 h post-surgery [median increase 18% (range -71 to 45%); P = 0.007]. TAT levels were significantly elevated from reperfusion and remained so at 48 h (P < 0.003), whereas D-dimer only increased at 24 h (P = 0.014). For the first time, we have demonstrated that in patients with SLI, platelet aggregation is increased following surgery and there is a mismatch in the balance between the coagulation and fibrinolytic pathways despite the use of aspirin and heparin. Thus in the early post-operative these patients exhibit a pro-thrombotic state.

Variability in responsiveness to clopidogrel in patients with intermittent claudication.

OBJECTIVE: The concept of clopidogrel resistance is frequently evoked in the cardiac literature. The variability of antiplatelet response in patients with intermittent claudication has not been investigated. The aim of this study was to describe the effect of the addition of clopidogrel to aspirin using ex vivo measures of platelet activation in patients with life-style limiting intermittent claudication. DESIGN OF STUDY: Data from randomised controlled trial. MATERIALS: Data from 67 patients with intermittent claudication taking part in a randomised controlled trial and who received clopidogrel in addition to aspirin was analysed. METHODS: Platelet activation was measured using whole-blood flow cytometric measurement of ADP-stimulated fibrinogen binding at baseline and 12h after administration of a loading dose of 300 mg clopidogrel. Patients continued to receive 75 mg clopidogrel daily for 30 days and platelet activation was again measured at day 30. Compliance with treatment was assessed by counting returned tablets. RESULTS: Six patients were excluded from analysis because of incomplete compliance with treatment. Six of the sixty-one patients (9.8%) showed no reduction in platelet activation 12h after administration of the loading dose of clopidogrel. At 30 days these six patients still showed no response to clopidogrel. Amongst the remaining 55 patients, the mean reduction in fibrinogen binding after clopidogrel administration was 51.5% (95% CI: 43.8-59.2). Amongst responders there was a wide variability in reduction of fibrinogen binding in response to clopidogrel (range 8.11-97.7%). Four of these patients (6.6%) showed a reduction of more than 95% in fibrinogen binding. CONCLUSIONS: Patients with intermittent claudication show a wide variability in their response to clopidogrel. While a small proportion of these patients shows no response at all, another small group appears to respond excessively to clopidogrel. Clinical studies are required to identify whether hyper-responders are at increased risk of bleeding complications and whether hyporesponders are at a higher risk of thrombotic events.

A preliminary study on the effects of exercising to maximum walking distance on platelet and endothelial function in patients with intermittent claudication.

BACKGROUND: Platelet and endothelial activation has been shown to be increased in patients with intermittent claudication (IC). Recent studies have suggested that exercise may induce further platelet activation. The aims of this study were to investigate the effect of exercising to maximum walking distance on platelet and endothelial function in patients with intermittent claudication who were receiving statin and aspirin therapy compared with age matched healthy controls. METHODS: Platelet aggregation through COX-mediated and thrombin receptor activator peptide (TRAP)-stimulated GPIIb/IIIa pathways was measured by the Ultegra point of care system in 20 patients with IC on aspirin and 20 healthy volunteers before, immediately and 1h after exercising to treadmill maximal walking distance (MWD). Soluble P-selectin, vWF and sICAM were measured using an enzyme linked immuno-sorbent assay technique. RESULTS: Baseline platelet aggregation was significantly reduced in patients with IC compared to volunteers (p<0.05). In patients, exercising to MWD significantly reduced platelet aggregation (COX, median -5% [range -24 to 13%]; p = 0.02; GPIIIa/IIb, median -13% [range -72 to 33%]; p = 0.02) immediately post-exercise which returned to baseline values at 1 h. There was no change in the healthy volunteers following the same median duration of exercise. Baseline sP-selectin levels were higher in the patients with IC compared to the healthy volunteers [Median values (interquartile range), 42.72 (33.28-54.24) versus 29.16 (24.40-34.10), p = 0.0003] but there were no differences in vWF levels. Both sP-selectin and vWF levels increased significantly in the control and patient group following exercise (p<0.005). sICAM were higher at baseline in the patients with IC but were unchanged following exercise [Median values (interquartile range),560.9 (405.5-739.4) versus 467.0 (325.7-643.4), p<0.05]. CONCLUSION: This study is the first to show that platelet aggregation is reduced immediately following treadmill exercise to maximum walking distance in patients with IC despite a rise in sP-selectin and vWF, suggesting endothelial activation. The inhibition of platelet aggregation after exercise in subjects on antiplatelet and statin therapy suggests that exercise is unlikely to exacerbate platelet thrombus formation in patients with IC.

Is carotid duplex scanning sufficient as the sole investigation prior to carotid endarterectomy?

Carotid endarterectomy (CEA) is the accepted treatment for certain patients who have had, or who are at risk of having, a stroke if they have a significant narrowing of the internal carotid artery. Rapid and accurate classification of the degree of stenosis is important as the benefit of surgery is highly dependent on this. The aim of this study was to assess whether the addition of angiography to duplex scanning resulted in a change in patient management in a unit where duplex scanning was used as the sole imaging investigation prior to CEA. The study population consisted of 64 patients with significant internal carotid artery stenosis on duplex scanning who were suitable for, and wished to be considered for, CEA. All patients underwent an angiogram. In this study 9 (14%) patients did not proceed to surgery on the basis of angiography and in a further 11 (17%) patients insufficient views of the distal vessel were obtained on duplex scanning. Three of these patients had extensive disease which excluded surgery. One patient experienced a transient ischaemic attack (TIA) at the time of angiography. In conclusion, this audit has highlighted the limitations in performing duplex scanning alone, and the costs that this can incur on the patient who may undergo an unnecessary operation. We cannot recommend duplex scanning as the sole investigation prior to CEA. There is need to evaluate the role of additional non-invasive carotid imaging such as magnetic resonance angiography or CT angiography in the assessment of these patients.