Long-Term Outcomes Following Elective Repair of Intact Abdominal Aortic Aneurysms: A Comparison Between Open Surgical and Endovascular Repair Using Linked Administrative and Clinical Registry Data.

OBJECTIVE: Compare long-term mortality, secondary intervention and secondary rupture following elective endovascular aneurysm repair (EVAR) and open surgical repair (OSR). BACKGROUND: EVAR has surpassed OSR as the most common procedure used to repair abdominal aortic aneurysm (AAA), but evidence regarding long-term outcomes is inconclusive. METHODS: We included patients in linked clinical registry and administrative data undergoing EVAR or OSR for intact AAA between January 2010 and June 2019. We used an inverse probability of treatment-weighted survival analysis to compare all-cause mortality, cause-specific mortality, secondary interventions and secondary rupture, and evaluate the impact of secondary interventions and secondary rupture on all-cause mortality. RESULTS: The study included 3460 EVAR and 427 OSR patients. Compared to OSR, the EVAR all-cause mortality rate was lower in the first 30 days [adjusted hazard ratio (HR) = 0.22, 95% confidence interval (CI) 0.140.33], but higher between 1 and 4 years (HR = 1.29, 95% CI 1.12-1.48) and after 4years (HR = 1.41, 95% CI 1.23-1.63). Secondary intervention rates were higher over the first 30 days (HR = 2.26, 95% CI 1.11-4.59), but lower between 1 and 4years (HR = 0.59, 95% CI 0.48-0.74). Secondary aortic intervention rates were higher across the entire follow-up period (HR = 2.52, 95% CI 2.06-3.07). Secondary rupture rates did not differ significantly (HR = 1.06, 95% CI 0.73-1.55). All-cause mortality beyond 1 year remained significantly higher for EVAR after adjusting for any secondary interventions, or secendary rupture. CONCLUSIONS: EVAR has an early survival benefit compared to OSR. However, elevated long-term mortality and higher rates of secondary aortic interventions and subsequent aneurysm repair suggest that EVAR may be a less durable method of aortic aneurysm exclusion.

Editor's Choice - Comparison of Outcomes for Major Contemporary Endograft Devices Used for Endovascular Repair of Intact Abdominal Aortic Aneurysms.

OBJECTIVE: To compare rates of mortality, rupture, and secondary intervention following endovascular repair (EVAR) of intact abdominal aortic aneurysms (AAA) using contemporary endograft devices from three major manufacturers. METHODS: This was a retrospective cohort study using linked clinical registry (Australasian Vascular Audit) and all payer administrative data. Patients undergoing EVAR for intact AAA between 2010 and 2019 in New South Wales, Australia were identified. Rates of all cause death, secondary rupture, and secondary intervention (subsequent aneurysm repair; other secondary aortic intervention) were compared for patients treated with Cook, Medtronic, and Gore standard devices. Inverse probability of treatment weighted proportional hazards and competing risk regression were used to adjust for patient, clinical, and aneurysm characteristics, using Cook as the referent device. RESULTS: This study identified 2 874 eligible EVAR patients, with a median follow up of 4.1 (maximum 9.5) years. Mortality rates were similar for patients receiving different devices (ranging between 7.0 and 7.3 per 100 person years). There was no statistically significant difference between devices in secondary rupture rates, which ranged between 0.4 and 0.5 per 100 person years. Patients receiving Medtronic and Gore devices tended to have higher crude rates of subsequent aneurysm repair (1.5 per 100 person years) than patients receiving Cook devices (0.8 per 100 person years). This finding remained in the adjusted analysis, but was only statistically significant for Medtronic devices (HR 1.57, 95% CI 1.02 - 2.47; HR 1.73, 95% CI 0.94 - 3.18, respectively). CONCLUSION: Major endograft devices have similar overall long term safety profiles. However, there may be differences in rates of secondary intervention for some devices. This may reflect endograft durability, or patient selection for different devices based on aneurysm anatomy. Continuous comparative assessments are needed to guide evidence for treatment decisions across the range of available devices.

The impact of COVID-19 pandemic on vascular registries and clinical trials.

Quality improvement programs and clinical trial research experienced disruption due to the coronavirus disease 2019 (COVID-19) pandemic. Vascular registries showed an immediate impact with significant declines in second-quarter vascular procedure volumes witnessed across Europe and the United States. To better understand the magnitude and impact of the pandemic, organizations and study groups sent grass roots surveys to vascular specialists for needs assessment. Several vascular registries responded quickly by insertion of COVID-19 variables into their data collection forms. More than 80% of clinical trials have been reported delayed or not started due to factors that included loss of enrollment from patient concerns or mandated institutional shutdowns, weighing the risk of trial participation on patient safety. Preliminary data of patients undergoing vascular surgery with active COVID-19 infection show inferior outcomes (morbidity) and increased mortality. Disease-specific vascular surgery study collaboratives about COVID-19 were created for the desire to study the disease in a more focused manner than possible through registry outcomes. This review describes the pandemic effect on multiple VASCUNET registries including Germany (GermanVasc), Sweden (SwedVasc), United Kingdom (UK National Vascular Registry), Australia and New Zealand (bi-national Australasian Vascular Audit), as well as the United States (Society for Vascular Surgery Vascular Quality Initiative). We will highlight the continued collaboration of VASCUNET with the Vascular Quality Initiative in the International Consortium of Vascular Registries as part of the Medical Device Epidemiology Network coordinated registry network. Vascular registries must remain flexible and responsive to new and future real-world problems affecting vascular patients.

The Relationship Between Aortic Aneurysm Surgery Volume and Peri-Operative Mortality in Australia.

OBJECTIVES: Operative caseload is thought to be associated with peri-operative mortality following intact aortic aneurysm repair. The aim was to study that association in the Australian setting, which has a unique healthcare provision system and geographical population distribution. METHODS: The Australasian Vascular Audit database was used to capture volume measurements for both individual surgeon and hospital and to separate it into quintiles (1, lowest, to 5, highest) for endovascular (EVAR), open surgical repair (OSR), and subgroups of repair types between 2010 and 2016. Multivariable logistic regression modelling was used to assess the impact of caseload volumes on in hospital mortality after adjustment for confounders. RESULTS: Volume counts were determined from 14,262 aneurysm repair procedures (4121 OSR, 10,106 EVAR). After exclusions, 2181 OSR (161 complex, 2020 standard) and 7547 EVAR (6198 standard, 1135 complex, 214 thoracic (TEVAR)) elective cases were available for volume analysis. Unadjusted mortality after EVAR was unaffected by either surgeon (Quintile 1, 1.0%; Quintile 5, 0.9%; p = .28) or hospital volume (Quintile 1, 0.8%; Quintile 5, 1.3%; p = .47). However, univariable analysis of the TEVAR subgroup revealed a significant correlation with hospital volume (Quintiles 1-2 vs. Quintiles 3-5; p = .02). Univariable analysis for OSR demonstrated a marginal, non-significant value for surgeon (Quintile 1, 4.0%; Quintile 5, 3.6%; p = .06), but not hospital volume (Quintile 1, 4.7%; Quintile 5, 4.0%; p = .67). After adjustment for confounders hospital volume remained a significant predictor of peri-operative TEVAR mortality (Quintile 1-2 vs. 3-5; OR 5.62, 95% CI 1.27-24.83; p = .02) and surgeon volume a predictor following standard OSR (Quintile 1-2 vs. Quintile 3-5; OR 2.15, 95% CI 1.21-3.83; p = .01). CONCLUSIONS: There is an inverse correlation between both surgeon volume of open aortic aneurysm repair, hospital volume of thoracic endovascular aneurysm repair and in hospital mortality. These findings suggest that in Australia TEVAR should be performed by high volume hospitals and OSR by high volume surgeons.

Few internal iliac artery aneurysms rupture under 4 cm.

OBJECTIVE: This study investigated the diameter of internal iliac artery (IIA) aneurysms (IIAAs) at the time of rupture to evaluate whether the current threshold diameter for elective repair of 3 cm is reasonable. The prevalence of concomitant aneurysms and results of surgical treatment were also investigated. METHODS: This was a retrospective analysis of patients with ruptured IIAA from seven countries. The patients were collected from vascular registries and patient records of 28 vascular centers. Computed tomography images taken at the time of rupture were analyzed, and maximal diameters of the ruptured IIA and other aortoiliac arteries were measured. Data on the type of surgical treatment, mortality at 30 days, and follow-up were collected. RESULTS: Sixty-three patients (55 men and 8 women) were identified, operated on from 2002 to 2015. The patients were a mean age of 76.6 years (standard deviation, 9.0; range 48-93 years). A concomitant common iliac artery aneurysm was present in 65.0%, 41.7% had a concomitant abdominal aortic aneurysm, and 36.7% had both. IIAA was isolated in 30.0%. The mean maximal diameter of the ruptured artery was 68.4 mm (standard deviation, 20.5 mm; median, 67.0 mm; range, 25-116 mm). One rupture occurred at <3 cm and four at <4 cm (6.3% of all ruptures). All patients were treated, 73.0% by open repair and 27.0% by endovascular repair. The 30-day mortality was 12.7%. Median follow-up was 18.3 months (interquartile range, 2.0-48.3 months). The 1-year Kaplan-Meier estimate for survival was 74.5% (standard error, 5.7%). CONCLUSIONS: IIAA is an uncommon condition and mostly coexists with other aortoiliac aneurysms. Follow-up until a diameter of 4 cm seems justified, at least in elderly men, although lack of surveillance data precludes firm conclusions. The mortality was low compared with previously published figures and lower than mortality in patients with ruptured abdominal aortic aneurysm.

Mortality after open aortic aneurysm surgery by Australasian surgeons trained in the endovascular era.

BACKGROUND: Reduced exposure of trainees to open repair (OR) of abdominal aortic aneurysm (AAA) during training has been considered detrimental to outcome. The Australasian experience is examined. METHODS: The Australasian Vascular Audit (AVA) was interrogated for AAA procedures between 1 January 2010 and 31 December 2014. Surgeons completing training before 2006 (group 1) were compared with those attaining their qualification subsequently (group 2). The Australian Institute of Health and Welfare (AIHW) database was also interrogated to confirm the trends over time of open and endovascular repair (EVAR) since 2000. Actual exposure to OR and EVAR of AAA by trainees from 2010 to 2014 was also extracted. RESULTS: One hundred and forty-six surgeons in group 1 performed 3049 OR compared with 997 for the 66 surgeons in group 2. Overall mortality for group 1 was 9.8% and for group 2, 15% (P < 0.0001). However, proportionately more ruptured AAA were treated in group 2 (31.5%) compared to group 1 (21.6%) (P < 0.0001). There was a slightly higher mortality in group 2 for ruptured but not intact aneurysm repair. Logistic regression analysis did not show the consultant group to be a significant variable in the model. EVAR was performed in 7409 patients during the study period; group 1 had a 1.5% mortality rate compared with 1.6% for group 2 (P = 0.76). AIHW data showed a trend of increasing EVAR with time. Considerable variation in OR exposure by trainees exists. CONCLUSION: Reduced exposure to OR by younger trainees did not significantly affect surgical outcome when compared with those surgeons trained in an earlier period.

Victorian Audit of Surgical Mortality is associated with improved clinical outcomes.

BACKGROUND: Improved outcomes are desirable results of clinical audit. The aim of this study was to use data from the Victorian Audit of Surgical Mortality (VASM) and the Victorian Admitted Episodes Dataset (VAED) to highlight specific areas of clinical improvement and reduction in mortality over the duration of the audit process. METHODS: This study used retrospective, observational data from VASM and VAED. VASM data were reported by participating public and private health services, the Coroner and self-reporting surgeons across Victoria. Aggregated VAED data were supplied by the Victorian Department of Health. Assessment of outcomes was performed using chi-squared trend analysis over successive annual audit periods. Because initial collection of data was incomplete in the recruitment phase, statistical analysis was confined to the last 3-year period, 2010-2013. RESULTS: A 20% reduction in surgical mortality over the past 5 years has been identified from the VAED data. Progressive increase in both surgeon and hospital participation, significant reduction in both errors in management as perceived by assessors and increased direct consultant involvement in cases returned to theatre have been documented. CONCLUSIONS: The benefits of VASM are reflected in the association with a reduction of mortality and adverse clinical outcomes, which have clinical and financial benefits. It is a purely educational exercise and continued participation in this audit will ensure the highest standards of surgical care in Australia. This also highlights the valuable collaboration between the Victorian Department of Health and the RACS.

Evaluating the value and impact of the Victorian Audit of Surgical Mortality.

INTRODUCTION: Since the Victorian Audit of Surgical Mortality (VASM) commenced in 2007, 95% of Victorian Fellows have agreed to participate and have provided data on the deaths of patients receiving surgical care. All public, and the majority of private, hospitals involved in the delivery of surgical services in Victoria have been submitting data on deaths associated with surgery. De-identified reports on this data are distributed in regular annual reports and case note review booklets. Although informal feedback on the perceived value of the audit was encouraging, a formal review of all aspects of the audit was felt necessary. METHODS: An independent formal review of VASM governance, documentation, datasets and data analysis was performed, in addition to a survey of 257 individuals (surgeons and other stakeholders) on the perceived impact of VASM. RESULTS: The review confirmed increasing participation and acceptance by surgeons since the inception of the project. Governance mechanisms were found to be effective and acknowledged by stakeholders and collaborators. Robust participation rates have been achieved, and stakeholders were generally satisfied with the quality of feedback. Suggestions for improvement were provided by some surgeons and hospitals. CONCLUSION: External review of VASM processes and procedures confirmed that the audit was operating effectively, with robust quality control and achieving the trust of stakeholders. The educational value of the audit to the surgical community was acknowledged and areas for future improvement have been identified.

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.

Use of a disposable tunneller for arterial bypass to the foot.

BACKGROUND: Performance of pedal artery bypass for limb salvage is well described. A tunneller is required to place the vein graft subcutaneously, but a suitable instrument to achieve this is not always available. METHODS: A disposable catheter passer used for ventriculo-peritoneal shunts is ideally suited to this purpose, and the technique of its use is described. CONCLUSIONS: Placement of the vein graft in a subcutaneous tunnel with minimal trauma is easily achieved using this instrument.

Cumulative sum control charts for assessing performance in arterial surgery.

BACKGROUND: The Melbourne Vascular Surgical Association (Melbourne, Australia) undertakes surveillance of mortality following aortic aneurysm surgery, patency at discharge following infrainguinal bypass and stroke and death following carotid endarterectomy. Quality improvement protocol employing the Deming cycle requires that the system for performing surgery first be analysed and optimized. Then process and outcome data are collected and these data require careful analysis. There must be a mechanism so that the causes of unsatisfactory outcomes can be determined and a good feedback mechanism must exist so that good performance is acknowledged and unsatisfactory performance corrected. A simple method for analysing these data that detects changes in average outcome rates is available using cumulative sum statistical control charts. METHODS: Data have been analysed both retrospectively from 1999 to 2001, and prospectively during 2002 using cumulative sum control methods. A pathway to deal with control chart signals has been developed. RESULTS: The standard of arterial surgery in Victoria, Australia, is high. In one case a safe and satisfactory outcome was achieved by following the pathway developed by the audit committee. CONCLUSION: Cumulative sum control charts are a simple and effective tool for the identification of variations in performance standards in arterial surgery. The establishment of a pathway to manage problem performance is a vital part of audit activity.

Effect of carotid bifurcation location on the length of internal carotid disease.

BACKGROUND: A relationship between the height of the carotid bifurcation and the extent of disease in the internal carotid artery has not been reported. The aim of the present study was to determine if such a correlation exists. METHODS: Fifty-one patients undergoing carotid endarterectomy had measurements made of the height of the carotid bifurcation from the sternoclavicular joint. The length of disease removed distal to the bifurcation after carotid endarterectomy was also measured. Correlation analysis was performed. RESULTS: There is a statistically significant negative correlation between the extent of disease in the internal carotid artery and the height of the bifurcation. CONCLUSIONS: A low carotid bifurcation correlates with a longer extent of disease in the internal carotid artery.

Melbourne vascular surgical association audit.

BACKGROUND: The formation of the Melbourne Vascular Surgical Association has led to the establishment of a vascular surgical audit programme that commenced in January 1999. This has allowed establishment of a benchmark for quality assurance in vascular surgery in Australia. METHODS: A consultative process allowed widespread adoption of the audit across all public hospital vascular units in Melbourne and the two largest regional centres in Victoria. Data were collected at two points during admission: at operation and at discharge. Risk stratification, using logistic regression and risk-adjusted ratios for adverse events was assessed for comparison of outcomes between units for the first 3 years of data collection. There is regular contact with all participants for data feedback and quality control. RESULTS: The standard of vascular surgery across Victoria is consistent, and there has been excellent compliance by all academic vascular units. Private practice data are less complete, and only half of the vascular surgeons have participated. CONCLUSIONS: A statewide audit process is feasible and viable. Coordination by the Melbourne Vascular Surgical Association is crucial for its continued success.