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Background: Informed consent (IC) is an ethical and legal prerequisite for trial participation, yet current approaches evaluating participant understanding for IC during recruitment lack consistency. No validated measure has been identified that evaluates participant understanding for IC based on their contributions during consent interactions. This paper outlines the development and formative evaluation of the Participatory and Informed Consent (PIC) measure for application to recorded recruitment appointments. The PIC allows the evaluation of recruiter information provision and evidence of participant understanding., Methods: Published guidelines for IC were reviewed to identify potential items for inclusion. Seventeen purposively sampled trial recruitment appointments from three diverse trials were reviewed to identify the presence of items relevant to IC. A developmental version of the measure (DevPICv1) was drafted and applied to six further recruitment appointments from three further diverse trials to evaluate feasibility, validity, stability and inter-rater reliability. Findings guided revision of the measure (DevPICv2) which was applied to six further recruitment appointments as above., Results: DevPICv1 assessed recruiter information provision (detail and clarity assessed separately) and participant talk (detail and understanding assessed separately) over 20 parameters (or 23 parameters for three-arm trials). Initial application of the measure to six diverse recruitment appointments demonstrated promising stability and inter-rater reliability but a need to simplify the measure to shorten time for completion. The revised measure (DevPICv2) combined assessment of detail and clarity of recruiter information and detail and evidence of participant understanding into two single scales for application to 22 parameters or 25 parameters for three-arm trials. Application of DevPICv2 to six further diverse recruitment appointments showed considerable improvements in feasibility (e.g. time to complete) with good levels of stability (i.e. test-retest reliability) and inter-rater reliability maintained., Conclusions: The DevPICv2 provides a measure for application to trial recruitment appointments to evaluate quality of recruiter information provision and evidence of patient understanding and participation during IC discussions. Initial evaluation shows promising feasibility, validity, reliability and ability to discriminate across a range of recruiter practice and evidence of participant understanding. More validation work is needed in new clinical trials to evaluate and refine the measure further.

Objectives: The aim of this study was to: 1) provide tissue validation of quantitative T 2 mapping to measure plaque lipid content; and 2) investigate whether this technique could discern differences in plaque characteristics between symptom-related and non-symptom-related carotid plaques., Background: Noninvasive plaque lipid quantification is appealing both for stratification in treatment selection and as a possible predictor of future plaque rupture. However, current cardiovascular magnetic resonance (CMR) methods are insensitive, require a coalesced mass of lipid core, and rely on multicontrast acquisition with contrast media and extensive post-processing., Methods: Patients scheduled for carotid endarterectomy were recruited for 3-T carotid CMR before surgery. Lipid area was derived from segmented T 2 maps and compared directly to plaque lipid defined by histology., Results: Lipid area (%) on T 2 mapping and histology showed excellent correlation, both by individual slices (R = 0.85, p < 0.001) and plaque average (R = 0.83, p < 0.001). Lipid area (%) on T 2 maps was significantly higher in symptomatic compared with asymptomatic plaques (31.5 ± 3.7% vs. 15.8 ± 3.1%; p = 0.005) despite similar degrees of carotid stenosis and only modest difference in plaque volume (128.0 ± 6.0 mm 3 symptomatic vs. 105.6 ± 9.4 mm 3 asymptomatic; p = 0.04). Receiver-operating characteristic analysis showed that T 2 mapping has a good ability to discriminate between symptomatic and asymptomatic plaques with 67% sensitivity and 91% specificity (area under the curve: 0.79; p = 0.012)., Conclusions: CMR T 2 mapping distinguishes different plaque components and accurately quantifies plaque lipid content noninvasively. Compared with asymptomatic plaques, greater lipid content was found in symptomatic plaques despite similar degree of luminal stenosis and only modest difference in plaque volumes. This new technique may find a role in determining optimum treatment (e.g., providing an indication for intensive lipid lowering or by informing decisions of stents vs. surgery)., (Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background and Purpose: In the Asymptomatic Carotid Surgery Trial-1 (ACST-1), 3120 patients with tight asymptomatic carotid stenosis were randomly assigned to medical treatment alone or to carotid endarterectomy and appropriate medication. Successful carotid endarterectomy significantly reduced 10-year stroke risk in younger patients. This study was undertaken to determine the risk of new occlusion and stroke during trial follow-up., Methods: Patients with contralateral occlusion at trial entry (n=276) or incomplete duplex follow-up (n=137) were excluded. Risk of occlusion and stroke in patients with occlusion was estimated by Kaplan-Meier analysis. Cox proportional hazard regression models were used to determine risk factors for developing new occlusion and stroke., Results: Median follow-up in 2707 patients was 80.0 months (interquartile range, 52.0-115.0). New occlusions occurred in 197 patients (1.1% per annum) but were more likely to occur in arteries with tight stenosis and in unoperated patients. Overall risk of stroke was 7.6% (95% confidence interval [CI], 6.6-8.7) and 15.5% (95% CI, 13.6-17.4) at 5 and 10 years, respectively; for patients with new occlusion, this significantly increased to 17.0% (95% CI, 11.6-22.4) and 20.8% (95% CI, 14.1-26.2), respectively (P<0.001). Stroke was significantly more likely to occur in patients developing occlusion (hazard ratio, 1.78; 95% CI, 1.26-2.51) irrespective of allocated treatment., Conclusions: New occlusions were uncommon after carotid endarterectomy in ACST-1. During long-term follow-up, occlusion and stroke were commoner among patients with ≥ 70% stenosis, most of whom had not undergone carotid endarterectomy. Occlusion was an independent prognostic risk factor for occurrence of stroke.

Objectives: To assess timeliness of carotid endarterectomy services in the United Kingdom., Design: Observational study with follow-up to March 2008., Setting: UK hospitals performing carotid endarterectomy., Participants: UK surgeons undertaking carotid endarterectomy from December 2005 to December 2007., Main Outcome Measures: Provision and speed of delivery of appropriate assessments of patients; carotid endarterectomy and operative mortality; 30 day postoperative mortality., Results: 240 (61% of those eligible) consultant surgeons took part from 102 (76%) hospitals and trusts. Of 9913 carotid endarterectomies recorded on hospital episode statistics, 5513 (56%) were included. Of the patients who underwent endarterectomy, 83% had a history of transient ischaemic attack or stroke. Of these recently symptomatic patients, 20% had their operation within two weeks of onset of symptoms and 30% waited more than 12 weeks. Operative mortality was 0.5% during the inpatient stay and 1.0% (95% confidence interval 0.7% to 1.3%) by 30 days., Conclusion: Only 20% of symptomatic patients had surgery within the two week target time set by the National Institute for Health and Clinical Excellence (NICE). Although operative mortality rates are comparable with those in other countries, some patients might experience disabling or fatal stroke while waiting for surgery and hence not be included in operative statistics. Major improvements in services are necessary to enable early surgery in appropriate patients in order to prevent strokes.

Objective: the aim of this study was to investigate the effect of currently recommended medical treatment (MT) on changes in carotid stenosis in a group of asymptomatic patients taken from the Asymptomatic Carotid Surgery Trial (ACST)., Method: collaborators in ACST were given information on MT for stroke prevention (including antiplatelet agents, lipid-lowering drugs, diabetic and hypertension control). Patients underwent clinical examination and duplex scanning at entry, 4 months following randomisation and annually thereafter. The cohort of patients studied were those randomised to MT with complete follow up duplex datasets at four years (n=219). None had undergone carotid endarterectomy (CEA) or developed ipsilateral carotid symptoms., Results: there was no change in median carotid stenosis over four years (baseline 79% (IQR 10%) and 4 year median 79% (IQR 10%)) a median difference of 0 with Q1=-5 and Q3=+5 (p=0.98 Wilcoxon one sample test), whilst in many patients' stenoses progressed and regressed during this time. No individual MT variable correlated with stenosis progression or regression., Conclusion: in this group of ACST patients on MT, mean carotid stenosis was unchanged over 4 years. Individual patients' stenoses progressed (and regressed) without symptoms occurring. An increase in stenosis should not be the sole basis for deciding to operate on an asymptomatic patient., (Copyright 2002 Elsevier Science Ltd.)

A total of 58 popliteal aneurysms were found in 40 patients presenting between June 1982 and May 1989. Of these, 51 were caused by atherosclerosis, and there were five post-stenotic aneurysms associated with entrapment, one mycotic and one post-traumatic aneurysm. There were 18 patients with bilateral aneurysms, and two others had the first side repaired elsewhere before referral to this hospital. Aneurysms were found at other sites in 16 patients. Urgent treatment was needed for 32 patients (80%). Two required streptokinase treatment to clear arteries distally. Three needed fasciotomy for compartment syndrome. Two patients had above-knee amputation. Of 36 urgent operations, 13 had postoperative complications (36%). Four grafts were later revised successfully. At mean follow-up of 23 months (range 3-96 months), three patients had claudication secondary to preoperative distal arterial occlusion, and one patient had residual mild foot drop. These operative results contrast sharply with the low complication rate after elective operation for popliteal aneurysm. In these patients, 14 asymptomatic aneurysms were repaired uneventfully. Four patients who did not undergo elective operation later developed acute thrombosis (3) and rupture (1). This experience supports our policy that early elective treatment for popliteal artery aneurysm is the most appropriate choice.