Effect of Telmisartan on the Peak Wall Stress and Peak Wall Rupture Index of Small Abdominal Aortic Aneurysms: An Exploratory Analysis of the TEDY Trial.

OBJECTIVE: This study was an unplanned exploratory analysis of a subset of participants from the Telmisartan in the Management of Abdominal Aortic Aneurysm (TEDY) trial. It aimed to assess the efficacy of the angiotensin 1 receptor blocker telmisartan in reducing abdominal aortic aneurysm (AAA) peak wall stress (PWS) and peak wall rupture index (PWRI) among individuals with small AAAs. METHODS: Participants with AAAs measuring 35 - 49 mm in maximum diameter were randomised to receive telmisartan 40 mg or identical placebo in the TEDY trial. Participants who had computed tomography angiography performed at entry and at least one other time point during the trial (12 or 24 months) were included in the current study. Orthogonal AAA diameter, PWS, and PWRI were measured using previously validated methods. The annual change in PWS and PWRI from baseline was compared between participants allocated telmisartan or placebo using linear mixed effects models. These models were either unadjusted or adjusted for risk factors that were different in the groups at entry (p < .100) or systolic blood pressure (SBP) at one year. RESULTS: Of the 207 participants recruited to TEDY, 124 were eligible for inclusion in this study. This study included 65 and 59 participants from the telmisartan and placebo groups, respectively. The PWS and PWRI were not significantly different in the two groups at baseline. Participants allocated telmisartan had a slower annual increase in PWS (-4.19; 95% CI -8.24, -0.14 kPa/year; p = .043) and PWRI (-0.014; 95% CI -0.026, -0.001; p = .032) compared with those allocated placebo after adjusting for risk factors. After adjustment for SBP at one year, telmisartan did not significantly reduce annual increases in PWS or PWRI. CONCLUSION: The findings of this study suggest that telmisartan limits the rate of increase in PWS and PWRI of small AAAs by reducing blood pressure.

Association of Diagnosis of Depression and Small Abdominal Aortic Aneurysm Growth.

BACKGROUND: Depression is associated with an increased risk of cardiovascular events but its association with abdominal aortic aneurysm (AAA) progression is unknown. This study examined if a diagnosis of depression was association with more rapid AAA growth. METHODS: Patients with small AAA measuring between 30 and 50 mm were recruited from surveillance programs at 4 Australian centres. Maximum AAA diameter was measured by ultrasound imaging using a standardised and reproducible protocol to monitor AAA growth. Depression was defined from medical records of treatment for depression at recruitment. Linear mixed effects modelling was performed to examine the independent association of depression with AAA growth. A propensity matched sub-analysis was performed. RESULTS: A total of 574 participants were included of whom 73 (12.7%) were diagnosed with depression. Participants were followed with a median of 3 (Inter-quartile range (IQR): 2, 5) ultrasound scans for a median of 2.1 (IQR: 1.1, 3.5) years. The unadjusted model suggested that annual AAA growth was non-significantly reduced (mean difference: -0.3 mm/year; 95% confidence interval (CI): -0.7, 0.2; P = 0.26) in participants with a diagnosis of depression compared to other participants. After adjustment for covariates, depression was not significantly associated with AAA growth (mean difference: -0.3 mm/year; 95% CI: -0.8, 0.2; P = 0.27). Findings were similar in the propensity matched sub-analysis. Sensitivity analyses investigating the impact of initial AAA diameter and follow up on the association of depression with AAA growth found no interaction. CONCLUSIONS: This study suggested that depression was not associated with faster AAA growth.

Immunosuppressive drugs for nontransplant comorbidities are not associated with abdominal aortic aneurysm growth.

Background: In the present study, we examined the association of immunosuppressant drug prescriptions with the growth of small abdominal aortic aneurysms (AAAs). Methods: Participants with an AAA measuring between 30 and 50 mm were recruited from four Australian centers. AAA growth was monitored by ultrasound. The immunosuppressant drugs included conventional disease-modifying antirheumatic drugs (eg, methotrexate, sulfasalazine, leflunomide), steroids, hydroxychloroquine, other immunosuppressant drugs (eg, cyclosporine, azacitidine), or a combination of these drugs. Linear mixed effects modeling was performed to examine the independent association of an immunosuppressant prescription with AAA growth. A subanalysis examined the association of steroids with AAA growth. Results: Of the 621 patients, 34 (5.3%) had been prescribed at least one (n = 26) or more (n = 8) immunosuppressant drug and had been followed up for a median period of 2.1 years (interquartile range, 1.1-3.5 years), with a median of three ultrasound scans (interquartile range, two to five ultrasound scans). No significant difference was found in AAA growth when stratified by a prescription of immunosuppressant drugs on either unadjusted (mean difference, 0.2 mm/y; 95% confidence interval [CI], -0.4 to 0.7; P = .589) or risk factor-adjusted (mean difference, 0.2 mm/y; 95% CI, -0.3 to 0.7; P = .369) analyses. The findings were similar for the unadjusted (mean difference, 0.0 mm/y; 95% CI, -0.7 to 0.7; P = .980) and risk factor-adjusted (mean difference, 0.1 mm/y; 95% CI, -0.6 to 0.7; P = .886) subanalyses focused on steroid use. Conclusions: The results from this study suggest that AAA growth is not affected by immunosuppressant drug prescription. Studies with larger sample sizes are needed before reliable conclusions can be drawn.

Association of Serum Lipoprotein (a) With the Requirement for a Peripheral Artery Operation and the Incidence of Major Adverse Cardiovascular Events in People With Peripheral Artery Disease.

Background The aim of this study was to assess the relationship between serum lipoprotein (a) (Lp[a]) concentration and the requirement for peripheral artery disease (PAD) operations or incidence of major adverse cardiovascular events. Methods and Results A total of 1472 people with PAD presenting with intermittent claudication (n=355), abdominal aortic aneurysm (n=989) or critical limb ischemia (n=128) were prospectively recruited from 4 outpatient clinics in Australia. Lp(a) was measured in serum samples collected at recruitment using an immunoassay. Participants were followed for a median (interquartile range) of 2.4 (0.1-6.1) years to record requirement for any PAD operation, defined to include any open or endovascular PAD intervention (lower limb peripheral revascularization, abdominal aortic aneurysm repair, other aneurysm repair, or carotid artery revascularization). Myocardial infarctions, strokes, and deaths were also recorded. The association of Lp(a) with events was assessed using Cox proportional hazard analysis adjusting for traditional risk factors. Participants with Lp(a) ≥30 mg/dL had a greater requirement for any PAD operation (hazard ratio, 1.20, 95% CI, 1.02-1.41) and lower limb peripheral revascularization alone (hazard ratio 1.33, 95% CI, 1.06-1.66) but no increased risk of major adverse cardiovascular events or all-cause mortality. Lp(a) ≥50 mg/dL and a 40 mg/dL increase in Lp(a) were also associated with an increased risk of lower limb peripheral revascularization alone but not with other outcomes. Conclusions In participants with PAD referred for hospital management those with high Lp(a) had greater requirement for lower limb peripheral revascularization but Lp(a) was not consistently associated with other clinical events.

Randomized Placebo-Controlled Trial Assessing the Effect of 24-Week Fenofibrate Therapy on Circulating Markers of Abdominal Aortic Aneurysm: Outcomes From the FAME -2 Trial.

Background There is no drug therapy for abdominal aortic aneurysm ( AAA ). FAME-2 (Fenofibrate in the Management of Abdominal Aortic Aneurysm 2) was a placebo-controlled randomized trial designed to assess whether administration of 145 mg of fenofibrate/d for 24 weeks favorably modified circulating markers of AAA. Methods and Results Patients with AAA s measuring 35 to 49 mm and no contraindication were randomized to fenofibrate or identical placebo. The primary outcome measures were the differences in serum osteopontin and kallistatin concentrations between groups. Secondary analyses compared changes in the circulating concentration of AAA -associated proteins, and AAA growth, between groups using multivariable linear mixed-effects modeling. A total of 140 patients were randomized to receive fenofibrate (n=70) or placebo (n=70). By the end of the study 3 (2.1%) patients were lost to follow-up and 18 (12.9%) patients had ceased trial medication. A total of 85% of randomized patients took ≥80% of allocated tablets and were deemed to have complied with the medication regimen. Patients' allocated fenofibrate had expected reductions in serum triglycerides and estimated glomerular filtration rate, and increases in serum homocysteine. No differences in serum osteopontin, kallistatin, or AAA growth were observed between groups. Conclusions Administering 145 mg/d of fenofibrate for 24 weeks did not significantly reduce serum concentrations of osteopontin and kallistatin concentrations, or rates of AAA growth in this trial. The findings do not support the likely benefit of fenofibrate as a treatment for patients with small AAA s. Clinical Trial Registration URL : www.anzctr.org.au . Unique identifier: ACTRN 12613001039774.

Inositol in the MAnaGemENt of abdominal aortic aneurysm (IMAGEN): study protocol for a randomised controlled trial.

BACKGROUND: An abdominal aortic aneurysm (AAA) is a focal dilation of the abdominal aorta and is associated with a risk of fatal rupture. Experimental studies suggest that myo-inositol may exert beneficial effects on AAAs through favourable changes to biological pathways implicated in AAA pathology. The aim of the Inositol in the MAnaGemENt of abdominal aortic aneurysm (IMAGEN) trial is to assess if myo-inositol will reduce AAA growth. METHODS/DESIGN: IMAGEN is a multi-centre, prospective, parallel-group, randomised, double-blind, placebo-controlled trial. A total of 164 participants with an AAA measuring ≥ 30 mm will be randomised to either 2 g of myo-inositol or identical placebo twice daily for 12 months. The primary outcome measure will be AAA growth estimated by increase in total infrarenal aortic volume measured on computed tomographic scans. Secondary outcome measures will include AAA diameter assessed by computed tomography and ultrasound, AAA peak wall stress and peak wall rupture index, serum lipids, circulating AAA biomarkers, circulating RNAs and health-related quality of life. All analysis will be based on the intention-to-treat principle at the time of randomisation. All patients who meet the eligibility criteria, provide written informed consent and are enrolled in the study will be included in the primary analysis, regardless of adherence to dietary allocation. DISCUSSION: Currently, there is no known medical therapy to limit AAA progression. The IMAGEN trial will be the first randomised trial, to our knowledge, to assess the value of myo-inositol in limiting AAA growth. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12615001209583 . Registered on 6 November 2015.

TElmisartan in the management of abDominal aortic aneurYsm (TEDY): The study protocol for a randomized controlled trial.

BACKGROUND: Experimental studies suggest that angiotensin II plays a central role in the pathogenesis of abdominal aortic aneurysm. This trial aims to evaluate the efficacy of the angiotensin receptor blocker telmisartan in limiting the progression of abdominal aortic aneurysm. METHODS/DESIGN: Telmisartan in the management of abdominal aortic aneurysm (TEDY) is a multicentre, parallel-design, randomised, double-blind, placebo-controlled trial with an intention-to-treat analysis. We aim to randomly assign 300 participants with small abdominal aortic aneurysm to either 40 mg of telmisartan or identical placebo and follow patients over 2 years. The primary endpoint will be abdominal aortic aneurysm growth as measured by 1) maximum infra-renal aortic volume on computed tomographic angiography, 2) maximum orthogonal diameter on computed tomographic angiography, and 3) maximum diameter on ultrasound. Secondary endpoints include change in resting brachial blood pressure, abdominal aortic aneurysm biomarker profile and health-related quality of life. TEDY is an international collaboration conducted from major vascular centres in Australia, the United States and the Netherlands. DISCUSSION: Currently, no medication has been convincingly demonstrated to limit abdominal aortic aneurysm progression. TEDY will examine the potential of a promising treatment strategy for patients with small abdominal aortic aneurysms. TRIAL REGISTRATION: Australian and Leiden study centres: Australian New Zealand Clinical Trials Registry ACTRN12611000931976 , registered on 30 August 2011; Stanford study centre: clinicaltrials.gov NCT01683084 , registered on 5 September 2012.

Validation of Australian data in the Australasian Vascular Audit.

BACKGROUND: Accuracy of data is important in any clinical audit. It is necessary to determine how complete the dataset is as well as the accuracy of the data that have been entered. The Australasian Vascular Audit has been operational for 4 years and a data validation process has been undertaken. METHOD: An independent data source is available, which is collected by the Australian Institute of Health and Welfare. This collects all public and private hospital data and is available for interrogation. Similarly, private-only data are available from the Medicare website. This has been compared with the Australasian Vascular Audit dataset to establish completeness of data collection. Quality of data collected has been verified by comparing accuracy of data fields with that present in patient records in a 5% random sample. RESULTS: For the 2 years studied, there was a 63% capture rate in Australia for all patients. In the private sector, only 50% of patients were captured with a significant decrease noted in 2013. The quality of data entered had a 2.6% error rate. CONCLUSION: There is a need to increase compliance with vascular audit in Australia and data accuracy is acceptable but could be improved.

Results from the Australasian Vascular Surgical Audit: the inaugural year.

The Australian and New Zealand Society for Vascular Surgery has incorporated a constitutional change to administer a self-funded compulsory vascular surgery audit since January 2010. This is a bi-national quality assurance activity that captures all procedures performed in both countries. Data is collected at two points in the clinical admission; at operation and at discharge and data entry is via the Internet. Security is stringent and confidentiality is guaranteed by Commonwealth privilege. Data privacy is maximized by encryption. The application is flexible and administered by a dedicated administrator with a help-desk facility. Reports are available to provide real-time feedback of user performance compared with the peer group data in key categories of arterial surgery. A structured hierarchy for data management has been established to assess four main categories of performance: mortality after aortic surgery, stroke and death after carotid surgery, patency and limb salvage after infrainguinal bypass and patency after arteriovenous access for haemodialysis. Data is analysed using risk-adjustment techniques and an algorithm for management of underperformance has been followed. Data validation has been performed. The outcomes in all categories have been of a high standard and correction of erroneous data in a single statistical outlier has negated underperformance. The audit has captured only 65% of the estimated procedures in Australia in the first year, but data quality is good. The feasibility of a complete compulsory bi-national audit has now been established and will be the benchmark for other craft groups in the current environment of accountability.

Development of the Australasian vascular surgical audit.

OBJECTIVE: The purpose of this study was to describe the development of the Australasian Vascular Audit that was created to unify audit activities under the umbrella of the Australian and New Zealand Society for Vascular Surgery as a Web-based application. METHODS: Constitutional change in late 2008 deemed participation in this audit compulsory for Society members. The Web-based application was developed and tested during 2009. Data for all open vascular surgery and for all endovascular procedures are collected at two points in the admission episode: at the time of operation and at discharge, and entered into the application. Data are analyzed to produce risk-adjusted outcomes. An algorithm has been developed to deal with outliers according to natural justice and to comply with the requirements of regulatory bodies. The Audit is protected by legislated privilege and is officially endorsed and indemnified by the Royal Australasian College of Surgeons. Confidentiality of surgeons and patients alike is ensured by a legally protected coding system and computer encryption system. Validation is by a verification process of 5% of members per year who are randomly selected. The application is completely funded by the Society. RESULTS: Data entry commenced on January 1, 2010. Over 40,000 vascular procedures were entered in the first year. The Audit application allows instantaneous on-line access to individual data and to deidentified group data and specific reports. It also allows real-time instantaneous production of log books for vascular trainees. The Audit has already gained recognition in the Australasian public arena during its first year of operation as an important benchmark of correct professional surgical behavior. Compliance has been extremely high in public hospitals but less so in private hospitals such that only 60% of members received a certificate of complete participation at the end of its first year of operation. CONCLUSION: An Internet-based compulsory audit of complete surgical practice is possible to create and be maintained by a society of surgeons with a membership of just over 200. The 60% compliance rate for complete data entry has created an immediate constitutional challenge for the Society. Future challenges are to improve total participation to an acceptable level and to ensure accurate data entry via a robust validation system.