Meta-Analysis of Genome-Wide Association Studies for Abdominal Aortic Aneurysm Identifies Four New Disease-Specific Risk Loci.

RATIONALE: Abdominal aortic aneurysm (AAA) is a complex disease with both genetic and environmental risk factors. Together, 6 previously identified risk loci only explain a small proportion of the heritability of AAA. OBJECTIVE: To identify additional AAA risk loci using data from all available genome-wide association studies. METHODS AND RESULTS: Through a meta-analysis of 6 genome-wide association study data sets and a validation study totaling 10 204 cases and 107 766 controls, we identified 4 new AAA risk loci: 1q32.3 (SMYD2), 13q12.11 (LINC00540), 20q13.12 (near PCIF1/MMP9/ZNF335), and 21q22.2 (ERG). In various database searches, we observed no new associations between the lead AAA single nucleotide polymorphisms and coronary artery disease, blood pressure, lipids, or diabetes mellitus. Network analyses identified ERG, IL6R, and LDLR as modifiers of MMP9, with a direct interaction between ERG and MMP9. CONCLUSIONS: The 4 new risk loci for AAA seem to be specific for AAA compared with other cardiovascular diseases and related traits suggesting that traditional cardiovascular risk factor management may only have limited value in preventing the progression of aneurysmal disease.

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.

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.

Net-based information on varicose vein treatments: a tangled web.

AIMS: 30-40% of individuals will be affected by varicose veins during their lifetime. Many will contemplate treatment and will access the (Inter)net for information. The aim of this study is to determine whether New Zealand-based websites are an accurate source of information for the public. METHODS: Inclusion criteria were New Zealand based websites that contained information on varicose vein treatments. These websites were identified using the search-engines Google and Yahoo. The first 60 websites from each were evaluated and subdivided into 4 groups based on web-site ownership: (1) Vein clinic/hospital; (2) Appearance medicine; (3) Online stores; (4) Health editorials; and (5) Medical resources. RESULTS: 46 of the 120 websites satisfied the inclusion criteria. 18 websites (39%) explained what varicose veins were. Information about treatment options was most comprehensive in the "Vein clinic/hospital" group. The "Appearance medicine" group mostly contained information on outpatient interventional therapies. "Health editorial" sites had lifestyle modification options. All the online herbal/health stores mentioned herbal treatment options. CONCLUSION: Few websites fully informed patients about treatment options while some simply advertised non-evidence based treatments. This study suggests that the Internet is not a reliable source of information and does not accurately inform patients about varicose veins and the treatment options.

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. METHODS: This was a clinical audit. CEAs performed from 1 January 2006 to 31 December 2008 at Christchurch hospital were identified. The value stream from initial presentation to surgery was mapped in two phases (phase 1; 2006-2007 and phase 2; 2008). Patients who had carotid intervention for asymptomatic carotid lesions were excluded. RESULTS: The relevant patient journey was documented in 81 patients (55 phase 1; 26 phase 2). Median time from initial presentation to carotid ultrasound was 5 days in phase 1 and 6 days in phase 2. Time from presentation to vascular surgery review was 22 days in phase 1 and 13 days in phase 2. Time from presentation to CEA significantly reduced from 83 to 32 days between phases (P < 0.005). CONCLUSIONS: There has been a significant decrease in time from presentation to operation between phase 1 and 2. The most significant change is reduced delay between vascular surgery review and CEA. There has been no improvement in urgency of referral for imaging or surgical review. This part of the patient journey is a target for improvement.

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. METHODS: A prospective audit of delays in discharge of vascular surgical admissions over a 6-month period was performed. Expected date and time of discharge was compared with actual date and time of discharge. Day-case patients, patients who died during admission and patients not under the direct care of the vascular team were excluded. RESULTS: There were 99 elective and 51 acute admissions accounting for 729 hospital bed days. The median (range) age was 72 years (21-92) and 94% of patients were living independently in the community. Forty-seven percent of patients were discharged on the planned day and time, 21% on the planned day but at a later-than-predicted time and 32% were delayed by more than 1 day. Delays identified in this audit accounted for 135 bed days. Fifteen percent of delays were due to causes that can be improved by internal organization (e.g. delayed paperwork). The majority of the delays (85%) were due to external factors such as lack of rehabilitation beds or lack of placement facilities in nursing homes. Elderly patients and acute admissions were more likely to have long delays in discharge. CONCLUSION: Delays in discharge of vascular surgical patients use a lot of acute surgical bed days. Strategies to prevent delays in discharge should include not only improving internal organization and early identification and referral of patients who require rehabilitation/placement but also increased funding for such essential non-acute services.

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.

Quality of clinical notes for vascular surgery admissions: a CRABEL score review.

AIM: To compare the quality of patient notes between acute and elective admissions in vascular surgery. METHOD: Patient notes from the 50 most recent acute and elective admissions on a vascular surgical unit were reviewed using the CRABEL score. Points for quality of record keeping were awarded in four categories: Initial Clerking, Subsequent Entries, Consent and Discharge Summary. Total scores were calculated as a percentage. One hundred per cent represents the minimum quality standard expected. Overall CRABEL scores were compared for differences in the quality of note keeping between acute and elective admissions. Further analysis identified areas that need improvement. RESULTS: The mean CRABEL score for acute admissions was 79.2% (77.0-81.3, 95% C.I.) compared to 81.3% (78.8-83.8, 95% C.I.) for elective admissions (t-test P= n.s.). When the individual categories were analysed no statistically significant difference was observed between the two groups for 'Subsequent Entries' and 'Consent' sections (t-test p= n.s.). 'Initial Clerking' category scored significantly better for elective 16.3 out of 20 (15.7-16.9, 95% C.I.) admissions compared to acute admissions 14.6 out of 20 (13.9-15.3, 95% C.I.), (t-test P= 0.00063). 'Discharge Summary' section also scored significantly better for elective admissions 9.9 out of 10 (9.9-10.0, 95% C.I.) compared to acute admissions 9.6 out of 10 (9.3-9.9, 95% C.I.), (t-test P= 0.040). CONCLUSION: There was no statistically significant difference in the overall quality of written patient notes between acute and elective admissions, however 'Initial Clerking' and 'Discharge Summary' were better documented for elective admissions. Both acute and elective admissions were observed to have substandard quality of record keeping.

Topical negative pressure wound therapy (TNPWT): current practice in New Zealand.

AIM: To survey current opinion, regarding TNPWT, from New Zealand vascular surgeons. METHOD: Registered vascular surgeons currently practicing in New Zealand were identified from the Vascular Society of New Zealand (VSNZ) database. A questionnaire was emailed asking if they used TNP in their vascular surgical practice and whether or not they considered themselves 'up to date' regarding published evidence for TNP. Surgeons were also asked how often and how successful they felt that TNP was in different clinical situations (arterial ulcers [after revascularisation]; venous ulcers; mixed arterial/venous ulcers; following debridement of the 'diabetic (Db) foot'; lower limb (LL) surgical wound infections/dehiscences; and lymphocoeles/seromas/lymph fistulas not treated successfully with conservative management). One email reminder, followed by a hard copy reminder was sent to those who failed to respond to the first email. RESULTS: Of 38 vascular surgeons 34 responded (89.5%). Median response time was 3.38 days (range 12 min-11.8 days). 28 (82%) vascular surgeons used TNP in their NZ clinical practice. 17 (50%) considered themselves up to date regarding published evidence, 8 (23.5%) admitted to not being up to date with the evidence and 9 (26%) did not know. TNP appears to be used most frequently and with most success following debridement of diabetic foot wounds and in the management of infected/dehisced surgical wounds. CONCLUSION: TNPWT is widely used by NZ vascular surgeons, despite many not considering themselves up to date regarding published evidence. It is most favoured for treating diabetic feet post debridement and for lower limb surgical wounds.

Who do you want to treat your varicose veins?

The management of varicose veins is evolving at pace but the speed of change often outstrips the evidence. Patients should expect to be offered the whole range of treatment options that are suitable for their particular circumstances. This range should include conservative management, surgery, endovenous ablation techniques, and ultrasound guided sclerotherapy. If all the options are not discussed, patients should ask why.

The Effect of Vacuum-assisted Closure on the Tissue Oxygenation of Venous Ulcers: A Pilot Study .

UNLABELLED: Background. Vacuum-assisted closure (V.A.C.® Therapy, KCI, San Antonio, TX) has been widely used to increase the healing rate of a variety of wounds. It has been hypothesized that one of the actions of VAC is to increase perfusion and subsequent oxygenation of tissue. The aim of the present study was to investigate the effect of VAC therapy on transcutaneous oximetry measurements (TCOM) of skin surrounding chronic venous ulcers. METHODS: This was a prospective, experimental pilot study. Patients undergoing compression therapy were recruited from a community wound clinic. All patients had ankle-brachial pressure indices (ABPI) > 0.8. Three TCOM values were taken from around the ulcer and a reference TCOM was taken from the chest. Negative pressure was applied on the ulcer at 125-mmHg continuous subatmospheric pressure and four-layer compression bandaging over the VAC drapes. The duration of the study was 6 days. On day 6, dressings were removed and TCOM was repeated at the same skin sites. RESULTS: Fourteen of the 17 patients completed the trial. The median age was 73 years (range 49-85). No significant difference was found in oxygen partial pressure pre-and post-VAC therapy around the ulcer site (mean 41.5 mmHg versus 40 mmHg [P = 0.67]). There was a significant difference in TCOM between the reference point and the periwound area (mean 60.5 versus 40 [P < 0.0005]). CONCLUSION: This pilot study suggests that VAC therapy does not change oxygen partial pressure around venous ulcers. TCOM of the skin around ulcers were low despite normal ABPIs.

Informed consent for vascular intervention: completing one audit loop.

AIM: To reaudit documentation of the process of informed consent in patients undergoing vascular surgical and vascular radiological procedures. METHOD: A retrospective audit of randomly selected elective vascular radiological and surgical admissions from October 2005-2006 was undertaken to assess the impact of a previous audit on the documentation of the consent process carried out in 2005. Outpatient clinic letters, handwritten entries in the patients' admission notes, and consent forms were scrutinised and data collated on which doctors took consent, when consent was obtained, what details of the consent process were documented, and whether additional information was made available to patients. RESULTS: 99 sets of notes were reviewed (surgical n=50, radiological n=49). For patients undergoing vascular surgery, the consent form was signed by a consultant in 16 (32%) cases compared to 2 (4%) in the previous audit (p=0.013: Chi-squared). Significantly more vascular radiological consent forms were signed by a consultant (43) compared with surgical consent forms (16) (p<0.001; Chi-squared). Documentation that the risks of surgery had been discussed with the patient was present in 31 (62%) surgical notes and in 20 cases such discussions were documented in letters from clinics. For radiological consent documentation, 34 (69.4%) patient notes recorded discussions regarding procedural risk. Twenty-two (44.9%) of the vascular radiological patients had such risks documented in their outpatient notes by a vascular surgeon compared with 1 (2%) (p <0.001; Chi-squared) in the previous audit. Additional written information was given to 7(14%) of the vascular surgical patients which was similar to the previous audit. No additional information was given to patients who underwent vascular radiological procedures. CONCLUSIONS: Significant improvements have been made since the previous audit with more surgical consultants signing the consent forms and increased documentation of the nature of radiological procedures and risks discussed in outpatient clinics. From the current audit, provision of additional written information (patient information sheets) was an area identified for future improvement.

Endovascular repair of mycotic aortic aneurysms.

The management of mycotic aneurysms is difficult, with high morbidity and mortality. Traditional open operative approaches include removal of infected material with either extra-anatomic reconstruction or in situ graft repair. Since the advent of endovascular aneurysm repair (EVAR) in the early 1990s, its use in the treatment of aneurysm disease has increased due to proven decrease in 30-day mortality. There have been few case studies reporting the use of EVAR for infected aneurysms. We describe two cases of mycotic aneurysm of the abdominal aorta that were successfully managed with EVAR.

Treatment delays for patients exiting an aortic aneurysm surveillance programme.

BACKGROUND: We have previously reported abdominal aortic aneurysm (AAA)-related mortality in patients who have completed surveillance. This study investigates the journey time of patients who exited the AAA surveillance programme at Christchurch Hospital and underwent elective repair to determine the factors contributing to the interval between completing surveillance and undergoing surgical repair. METHODS: A retrospective review of patient notes was carried out for 25 patients who underwent elective repair of their AAA after exiting the surveillance programme between November 2000 and September 2005. RESULTS: The median time interval between exiting the programme and undergoing repair for patients fit for repair was 6 months. During this waiting period, there were two aneurysm-related deaths. Analysis of the patient journeys showed that those with significant comorbidity, that is, patients who required additional investigation by other clinicians (n = 7), had a median time to repair of 35 weeks. This was substantially increased compared with a median time of 22.5 weeks to repair for the rest (n = 18). CONCLUSION: At our institution the median time for completion of surveillance to repair was 6 months. An AAA with a diameter of 55 mm has an expected risk of rupture of 5%, with mortality approaching 90%. In our series, mortality was 4.9% (two patients died while awaiting repair), consistent with expected figures. Factors contributing to this delay of 6 months to repair were identified. Modifications to this journey are suggested to improve the time interval and therefore hopefully reduce the aneurysm-related mortality in this group.