David R. Lewis

A sequence variant associated with sortilin-1 (SORT1) on 1p13.3 is independently associated with abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) is a common human disease with a high estimated heritability (0.7); however, only a small number of associated genetic loci have been reported to date. In contrast, over 100 loci have now been reproducibly associated with either blood lipid profile and/or coronary artery disease (CAD) (both risk factors for AAA) in large-scale meta-analyses. This study employed a staged design to investigate whether the loci for these two phenotypes are also associated with AAA. Validated CAD and dyslipidaemia loci underwent screening using the Otago AAA genome-wide association data set. Putative associations underwent staged secondary validation in 10 additional cohorts. A novel association between the SORT1 (1p13.3) locus and AAA was identified. The rs599839 G allele, which has been previously associated with both dyslipidaemia and CAD, reached genome-wide significance in 11 combined independent cohorts (meta-analysis with 7048 AAA cases and 75 976 controls: G allele OR 0.81, 95% CI 0.76-0.85, P = 7.2 × 10(-14)). Modelling for confounding interactions of concurrent dyslipidaemia, heart disease and other risk factors suggested that this marker is an independent predictor of AAA susceptibility. In conclusion, a genetic marker associated with cardiovascular risk factors, and in particular concurrent vascular disease, appeared to independently contribute to susceptibility for AAA. Given the potential genetic overlap between risk factor and disease phenotypes, the use of well-characterized case-control cohorts allowing for modelling of cardiovascular disease risk confounders will be an important component in the future discovery of genetic markers for conditions such as AAA.

COMPOSITION OF VOLATILE ORGANIC COMPOUNDS IN DIATHERMY PLUME AS DETECTED BY SELECTED ION FLOW TUBE MASS SPECTROMETRY

Background:  There is some evidence that surgical plume may pose a risk to health professionals, but the risks posed by volatile organic compounds have not been thoroughly investigated.

Overcoming aspirin resistance: Increased platelet inhibition with combination aspirin and clopidogrel and high dose aspirin therapy in aspirin resistant patients with peripheral vascular disease

Overcoming aspirin resistance: Increased platelet inhibition with combination aspirin and clopidogrel and high dose aspirin therapy in aspirin resistant patients with peripheral vascular disease -

Patient flow to carotid endarterectomy: hastening the patient journey

Background:  Early carotid endarterectomy (CEA) after stroke or transient ischaemic attack is the proposed standard of care to prevent recurrent ischaemic events in selected patients. The aim of this study was to investigate if this standard is achieved in a tertiary vascular unit.

Cyanoacrylate embolization of endoleaks after abdominal aortic aneurysm repair

Introduction:  Type II endoleaks occur in up to a fifth of endoluminal repairs for abdominal aortic aneurysms and are commonly treated when aortic sac expansion can be demonstrated. Technical failure is common when catheter‐guided particulates or coil embolic agents are used. Presented here is a feasibility study using catheter‐directed N‐butyl‐2‐cyanoacrylate (Histoacryl, Braun, Tuttlingen, Germany) embolotherapy.

Diastasis Recti and Abdominal Aortic Aneurysm

An association between abdominal aortic aneurysm (AAA) and abdominal wall hernia has been suggested, possibly reflecting a common collagen disorder. The same mechanism may also cause a greater frequency of diastasis recti among patients at risk of developing AAA. Diastasis recti could be used to identify patients at risk of AAA, with implications for AAA screening. The aim of this study was to determine whether an association between diastasis recti and AAA could be demonstrated. The preoperative computed tomographic (CT) scans of 75 male patients undergoing elective AAA repair were retrospectively examined and linea alba width recorded at supraumbilical and subumbilical levels. Measurements were compared with controls frequency matched for age. Fifty patients with AAA were observed to have supraumbilical diastasis recti on preoperative CT compared with 47 controls. Mean linea alba width was not significantly different between the two groups at either the supraumbilical (19.3 mm vs 20.7 mm, p = .45) or subumbilical (3.6 mm vs 4.3 mm, p = .43) level. The findings do not support the hypothesis that the presence of diastasis recti can serve as an indication to select male patients for screening for AAA.

Delays in discharge of vascular surgical patients: a prospective audit

Aim:  To quantify delays in discharge for vascular surgical patients and identify causes of such delays.

POINT OF CARE TESTING OF ASPIRIN RESISTANCE IN PATIENTS WITH VASCULAR DISEASE

Introduction:  The reported range in rates of aspirin resistance (5.5–60%) may reflect difficulties in studying platelet function and the variety of tests used. This study used a platelet function analyzer (PFA‐100) to prospectively document aspirin resistance in a cohort of patients with arterial disease.

COMPUTED TOMOGRAPHY ARTERIOGRAPHY TO ASSESS GREATER SAPHENOUS VEIN AS A CONDUIT FOR PERIPHERAL BYPASS

Background:  To determine whether computed tomography arteriography of the lower extremities (64‐slice volume computed tomography (CT)), used in delineating the arterial tree in peripheral vascular disease, is useful in assessing suitability of greater saphenous vein as a vascular conduit for peripheral bypass grafting for limb‐threatening lower limb ischaemia. A search of published works in August 2005 showed no similar study has been published.

Correlation of ABCD2 Score with Degree of Internal Carotid Artery Stenosis: An Observational Pilot Study

BACKGROUND ABCD(2) is a validated scoring system that predicts the risk of stroke after a transient ischemic attack (TIA). International guidelines suggest that patients with a low score can be investigated on an outpatient basis. The ABCD2 score, however, cannot identify which patients have significant internal carotid artery (ICA) disease, and this group of patients could benefit from rapid access carotid endarterectomy (RACE). Studies have shown that patients with significant carotid artery disease have a higher risk of neurologic events or recurrent stroke. The aim of this study was to document the range of ABCD2 scores in patients with carotid artery-related TIA, and investigate any correlation between the ABCD2 scores and ICA stenosis. METHODS Patients undergoing carotid duplex ultrasound scan for TIA from January 2009 to May 2010 from two vascular units were identified from the vascular database retrospectively. Clinical notes were reviewed and outcomes measures were recorded: ABCD2 scores (age, blood pressure, clinical features, diabetes, and duration) and carotid plaque morphology. RESULTS Ninety-seven patients with a mean age of 74 (range 56-90) years had ICA stenoses of ≥50% up to 100%. Fifty-seven patients had an ABCD2 score of ≤4. There was no significant correlation between ABCD2 scores and degree of ICA stenosis nor carotid plaque morphology (P=0.2, r=1.0, and P=1.0, r=0.0007, respectively). CONCLUSIONS Because no correlation between ABCD2 scores and the degree of ICA stenosis was found, all patients with carotid territory TIA should undergo urgent imaging of the carotid arteries because a high proportion of these patients may benefit from RACE.