Effect of EVAR on International Ruptured AAA Mortality-Sex and Geographic Disparities.

Background: We sought to investigate the differential impact of EVAR (endovascular aneurysm repair) vis-à-vis OSR (open surgical repair) on ruptured AAA (abdominal aortic aneurysm) mortality by sex and geographically. Methods: We performed a retrospective study of administrative data on EVAR from state statistical agencies, vascular registries, and academic publications, as well as ruptured AAA mortality rates from the World Health Organization for 14 14 states across Australasia, East Asia, Europe, and North America. Results: Between 2011-2016, the proportion of treatment of ruptured AAAs by EVAR increased from 26.1 to 43.8 percent among females, and from 25.7 to 41.2 percent among males, and age-adjusted ruptured AAA mortality rates fell from 12.62 to 9.50 per million among females, and from 34.14 to 26.54 per million among males. The association of EVAR with reduced mortality was more than three times larger (2.2 vis-à-vis 0.6 percent of prevalence per 10 percentage point increase in EVAR) among females than males. The association of EVAR with reduced mortality was substantially larger (1.7 vis-à-vis 1.1 percent of prevalence per 10 percentage point increase in EVAR) among East Asian states than European+ states. Conclusions: The increasing adoption of EVAR coincided with a decrease in ruptured AAA mortality. The relationship between EVAR and mortality was more pronounced among females than males, and in East Asian than European+ states. Sex and ethnic heterogeneity should be further investigated.

Outcomes Following Intact and Ruptured Aneurysm Repair across Nations: Analysis of International Registry Data from the VASCUNET Collaboration 2014 - 2019.

OBJECTIVE: To determine the peri-operative mortality rate for intact and ruptured abdominal aortic aneurysm (AAA) repair in 10 countries and to compare practice and outcomes over a six year period by age, sex, and geographic location. METHODS: This VASCUNET study used prospectively collected data from vascular registries in 10 countries on primary repair of intact and ruptured AAAs undertaken between January 2014 and December 2019. The primary outcome was peri-operative death (30 day or in hospital). Logistic regression models were used to estimate the association between peri-operative death, patient characteristics, and type of procedure. Factors associated with the use of endovascular aortic aneurysm repair (EVAR) were also evaluated. RESULTS: The analysis included 50 642 intact and 9 453 ruptured AAA repairs. The proportion of EVARs for intact repairs increased from 63.4% in 2014 to 67.3% in 2016 before falling to 62.3% in 2019 (p < .001), but practice varied between countries. EVAR procedures were more common among older patients (p < .001) and men (p < .001). Overall peri-operative mortality after intact AAA repair was 1.4% (95% confidence interval [CI] 1.3 - 1.5%) and did not change over time. Mortality rates were stable within countries. Among ruptured AAA repairs, the proportion of EVARs increased from 23.7% in 2014 to 35.2% in 2019 (p < .001). The average aortic diameter was 7.8 cm for men and 7.0 cm for women (p < .001). The overall peri-operative mortality rate was 31.3% (95% CI 30.4 - 32.2%); the rates were 36.0% (95% CI 34.9 - 37.2%) for open repair and 19.7% (95% CI 18.2 - 21.3%) for EVAR. This difference and shift to EVAR reduced peri-operative mortality from 32.6% (in 2014) to 28.7% (in 2019). CONCLUSION: The international practice of intact AAA repair was associated with low mortality rates in registry reported data. There remains variation in the use of EVAR for intact AAAs across countries. Overall peri-operative mortality remains high after ruptured AAA, but an increased use of EVAR has reduced rates over time.

Peri-Operative Mortality and Survival After Repair of Abdominal Aortic Aneurysm in Advanced Age Patients: A National Study from the Norwegian Registry for Vascular Surgery Focused on Nonagenarians.

OBJECTIVE: Treatment of abdominal aortic aneurysm (AAA) in nonagenarians has become more frequent. This national observational cohort study aimed to investigate peri-operative mortality and survival after AAA surgery in nonagenarians in Norway. METHODS: All AAA repairs registered in the Norwegian Registry for Vascular Surgery from 2015 to 2021 were identified and stratified into nonagenarians > 90 years old (n = 77), octogenarians 80 - 89 years old (n = 1 362), and patients < 80 years old (n = 4 590). The patient characteristics and comorbidities were recorded, and the 30 and 90 day mortality rates were calculated. Kaplan-Meier analysis was performed to obtain the estimated median survival and survival curves. RESULTS: In the nonagenarians, the 30 day mortality rates were 2.5% in asymptomatic patients, 33.3% in symptomatic patients, and 59.1% in the patients with a ruptured AAA (rAAA). The estimated median survival (years) were 3.3 (95% confidence interval [CI] 1.95 - 4.59) for asymptomatic AAA, 2.9 (interquartile range [IQR] 2.82, 5.80) for symptomatic AAA, and 0.1 for rAAA (IQR 0.01, 3.04). For nonagenarians surviving the first 90 days, the estimated median survival (years) were 4.2 (95% CI 2.56 - 5.88) for asymptomatic AAA, 3.4 (IQR 2.86, 5.80) for symptomatic AAA, and 3.8 (IQR 1.49, 4.85) for rAAA. The 90 day mortality rates were 100.0%, 80.0%, and 62.5% for asymptomatic, symptomatic, and rAAA, respectively, after open surgical repair (OSR), and 5.1%, 10.0%, and 50.0%, respectively, after endovascular aortic repair (EVAR). CONCLUSION: Peri-operative mortality and survival results after AAA surgery in nonagenarians support treatment of selected asymptomatic patients. The 90 day survivors had an expected survival of more than three years, enabling balanced decision making regarding surgical vs. conservative treatment options in this challenging cohort. EVAR is the treatment method of choice for AAA in nonagenarians because most of them would probably live longer untreated than if treated by OSR.

Antithrombotic and Lipid Lowering Therapy is Associated With Improved Survival After Vascular Surgery: A Population Based Study From Norway.

OBJECTIVE: This population based retrospective cohort study aimed to investigate the association between combined treatment with lipid lowering drugs and antiplatelet or anticoagulation therapy and long term survival following vascular surgery in Norway. METHODS: The study included all patients who were registered for the treatment of carotid stenosis, abdominal aortic aneurysm (AAA), and atherosclerotic lower extremity arterial disease (LEAD) in the Norwegian Registry for Vascular Surgery between 2015 and 2019 and who were discharged alive. Clinical and medication details were retrieved from the register. Survival was assessed with Kaplan-Meier analysis and a multivariable Cox regression model. Stratification was according to treatment group, patient sex, and if patients received the recommended medications or not. Recommended medications were defined as lipid lowering drugs, usually statins, and antiplatelets, or sometimes anticoagulants, when comorbidity indicated anticoagulation therapy. RESULTS: In total, 15 810 patients had LEAD, 4 080 patients AAA, and 2 194 patients had carotid stenosis. In all treatment groups, survival was superior for patients who used the recommended medications upon discharge. The difference was greatest in patients with LEAD with mean survival periods of 4.33 (95% CI 4.29 - 4.36) and 3.7 (95% CI 3.64 - 3.77) years in patients discharged with and without the recommended medications, respectively (p < .001). The mean survival periods were 4.67 (95% CI 4.61 - 4.73) and 4.34 (95% CI 4.24 - 4.44) years in patients with AAA discharged with and without the recommended medications, respectively (p < .001). Cox regression analysis showed a statistically significantly lower mortality rate for patients discharged with the recommended medications for LEAD (HR 0.58; p < .001) and AAA (HR 0.57; p < .001). CONCLUSION: The recommended medications were associated with improved survival in all treatment groups and both sexes. The survival difference was statistically significant in patients with LEAD and AAA. Patients with LEAD had the greatest improvement; therefore, the recommended secondary prophylaxis is especially important in these patients.

Editor's Choice - The VASCUNExplanT Project: An International Study Assessing Open Surgical Conversion of Failed Non-Infected Endovascular Aortic Aneurysm Repair.

OBJECTIVE: The need for open surgical conversion (OSC) after failed endovascular aortic aneurysm repair (EVAR) persists, despite expanding endovascular options for secondary intervention. The VASCUNExplanT project collected international data to identify risk factors for failed EVAR, as well as OSC outcomes. This retrospective cross sectional study analysed data after OSC for failed EVAR from the VASCUNET international collaboration. METHODS: VASCUNET queried registries from its 28 member countries, and 17 collaborated with data from patients who underwent OSC (2005 - 2020). Any OSC for infection was excluded. Data included demographics, EVAR, and OSC procedural details, as well as post-operative mortality and complication rates. RESULTS: There were 348 OSC patients from 17 centres, of whom 33 (9.4%) were women. There were 130 (37.4%) devices originally deployed outside of instructions for use. The most common indication for OSC was endoleak (n = 143, 41.1%); ruptures accounted for 17.2% of cases. The median time from EVAR to OSC was 48.6 months [IQR 29.7, 71.6]; median abdominal aortic aneurysm diameter at OSC was 70.5 mm [IQR 61, 82]. A total of 160 (45.6%) patients underwent one or more re-interventions prior to OSC, while 63 patients (18.1%) underwent more than one re-intervention (range 1 - 5). Overall, the 30 day mortality rate post-OSC was 11.8% (n = 41), 11.1% for men and 18.2% for women (p = .23). The 30 day mortality rate was 6.1% for elective cases, and 28.3% for ruptures (p < .0001). The predicted 90 day survival for the entire cohort was 88.3% (95% CI 84.3 - 91.3). Multivariable analysis revealed rupture (OR 4.23; 95% CI 2.05 - 8.75; p < .0001) and total graft explantation (OR 2.10; 95% CI 1.02 - 4.34; p = .04) as the only statistically significant predictive factors for 30 day death. CONCLUSION: This multicentre analysis of patients who underwent OSC shows that, despite varying case mix and operative techniques, OSC is feasible but associated with significant morbidity and mortality rates, particularly when performed for rupture.

Editor's Choice - Sex Related Differences in Indication and Procedural Outcomes of Carotid interventions in VASCUNET.

OBJECTIVE: It has been suggested that peri-operative complications after carotid surgery may be higher in women than in men. This assumption may affect the treatment patterns, and it is thus possible that carotid endarterectomy (CEA) is provided to women less often. The aim of the current VASCUNET study was to determine sex related differences in operative risk in routine clinical practice among non-selected patients undergoing carotid revascularisation. METHODS: Data on CEA and carotid artery stenting (CAS) from 14 vascular registries were collected and amalgamated. Comprehensive data were available for 223 626 carotid artery procedures; these were analysed overall and by country. The primary outcome was any stroke and or death within 30 days of carotid revascularisation. Secondary outcomes were stroke, death, or any major cardiac event or haemorrhage leading to re-operation. RESULTS: Of the procedures, 34.8% were done in women. The proportion of CEA for asymptomatic stenosis compared with symptomatic stenosis was significantly higher among women than men (38.4% vs. 36.9%, p < .001). The proportion of octogenarians was higher among women than men who underwent CEA in both asymptomatic (21.2% vs. 19.9%) and symptomatic patients (24.3% vs. 21.4%). In the unadjusted analysis of symptomatic and asymptomatic patients, there were no significant differences between men and women in the rate of post-operative combined stroke and or death, any major cardiac event, or combined death, stroke, and any major cardiac event after CEA. Also, after stenting for asymptomatic or symptomatic carotid stenosis, there were no significant differences between men and women in the rate of post-operative complications. In adjusted analyses, sex was not significantly associated with any of the end points. Higher age and CAS vs. CEA were independently associated with all four end points. CONCLUSION: This study confirmed that, in a large registry among non-selected patients, no significant sex related differences were found in peri-operative complication rates after interventions for carotid stenosis.

Association Between Hospital Volume and Failure to Rescue After Open or Endovascular Repair of Intact Abdominal Aortic Aneurysms in the VASCUNET and International Consortium of Vascular Registries.

OBJECTIVE: To investigate the association between hospital volume and failure to rescue (FtR), after open repair (OAR), and endovascular repair (EVAR) of intact abdominal aortic aneurysms (AAA) among centers participating in the VASCUNET and International Consortium of Vascular Registries. SUMMARY OF BACKGROUND DATA: FtR (ie, in-hospital death following major complications) is a composite end-point representing the inability to treat complications effectively and prevent death. METHODS: Using data from 8 vascular registries, complication and mortality rates after intact AAA repair were examined (n = 60,273; EVAR-43,668; OAR-16,605). A restricted analysis using pooled data from 4 countries (Australia, Hungary, New Zealand, and USA) reporting data on all postoperative complications (bleeding, stroke, cardiac, respiratory, renal, colonic ischemia) was performed to identify risk-adjusted association between hospital volume and FtR. RESULTS: The most frequently reported complications were cardiac (EVAR-3.0%, OAR-8.9%) and respiratory (EVAR-1.0%, OAR-5.7%). In adjusted analysis, 4.3% of EVARs and 18.5% of OARs had at least 1 complication. The overall FtR rate was 10.3% after EVAR and 15.7% after OAR. Subjects treated in the highest volume centers (Q4) had 46% and 80% lower odds of FtR after EVAR (OR = 0.54; 95% CI = 0.34-0.87; P = 0.04) and OAR (OR = 0.22; 95% CI = 0.11-0.44; P < 0.001) when compared to lowest volume centers (Q1), respectively. Colonic ischemia had the highest risk of FtR for both procedures (adjusted predicted risks, EVAR: 27%, 95% CI 14%-45%; OAR: 30%, 95% CI 17%-46%). CONCLUSIONS: In this multi-national dataset, FtR rate after intact AAA repair with EVAR and OAR is significantly associated with hospital volume. Hospitals in the top volume quartiles achieve the lowest mortality after a complication has occurred.

Editor's Choice - Variation in Intact Abdominal Aortic Aneurysm Repair Outcomes by Country: Analysis of International Consortium of Vascular Registries 2010 - 2016.

OBJECTIVE: Outcomes for intact abdominal aortic aneurysm (AAA) repair vary over time and by healthcare system, country, and surgeon. The aim of this study was to analyse peri-operative mortality for intact AAA repair in 11 countries over time and compare outcomes by gender, age, and geographical location. METHODS: Prospective data on primary repair of intact AAA were collected from 11 countries through the International Consortium of Vascular Registries (ICVR) and analysed for two time periods, 2010 - 2013 and 2014 - 2016. The primary outcome was peri-operative mortality after endovascular aneurysm repair (EVAR) and open surgical repair (OSR). Multivariable logistic regression models were used to adjust for differences in patient characteristics. RESULTS: A total of 103 715 patients were included. The percentage of patients undergoing EVAR increased from 63.6% to 71.2% (p < .001) over the study period. This proportion varied by country from 35% in Hungary to 81% in the United States. Overall peri-operative mortality decreased from 2.1% to 1.6 % (p < .001). Mortality also declined significantly over time for both OSR 4.2% to 3.6 % (p = .002) and EVAR 1.0% to 0.7% (p = .002). Mortality was significantly higher for female than male patients (3.0% vs. 1.6% p < .001). The percentage of patients > 80 years old undergoing AAA repair remained constant at 23.6% (p = .91). Peri-operative mortality was higher for patients > 80 years than for those < 80 years old (2.7% vs. 1.6% p < .001). Forty-six per cent (n = 275) of all EVAR deaths occurred in the over 80s. CONCLUSION: The proportion of AAA repairs performed using EVAR has increased over time. Peri-operative mortality continues to decline for both OSR and EVAR. Outcomes however were significantly worse for both women and those aged over 80, so efforts should be focused on these patient groups to further reduce elective AAA mortality rates.

Editor's Choice - Optimal Threshold for the Volume-Outcome Relationship After Open AAA Repair in the Endovascular Era: Analysis of the International Consortium of Vascular Registries.

OBJECTIVE: As open abdominal aortic aneurysm (AAA) repair (OAR) rates decline in the endovascular era, the endorsement of minimum volume thresholds for OAR is increasingly controversial, as this may affect credentialing and training. The purpose of this analysis was to identify an optimal centre volume threshold that is associated with the most significant mortality reduction after OAR, and to determine how this reflects contemporary practice. METHODS: This was an observational study of OARs performed in 11 countries (2010 - 2016) within the International Consortium of Vascular Registry database (n = 178 302). The primary endpoint was post-operative in hospital mortality. Two different methodologies (area under the receiving operating curve optimisation and Markov chain Monte Carlo procedure) were used to determine the optimal centre volume threshold associated with the most significant mortality improvement. RESULTS: In total, 154 912 (86.9%) intact and 23 390 (13.1%) ruptured AAAs were analysed. The majority (63.1%; n = 112 557) underwent endovascular repair (EVAR) (OAR 36.9%; n = 65 745). A significant inverse relationship between increasing centre volume and lower peri-operative mortality after intact and ruptured OAR was evident (p < .001) but not with EVAR. An annual centre volume of between 13 and 16 procedures per year was associated with the most significant mortality reduction after intact OAR (adjusted predicted mortality < 13 procedures/year 4.6% [95% confidence interval 4.0% - 5.2%] vs. ≥ 13 procedures/year 3.1% [95% CI 2.8% - 3.5%]). With the increasing adoption of EVAR, the mean number of OARs per centre (intact + ruptured) decreased significantly (2010 - 2013 = 35.7; 2014 - 2016 = 29.8; p < .001). Only 23% of centres (n = 240/1 065) met the ≥ 13 procedures/year volume threshold, with significant variation between nations (Germany 11%; Denmark 100%). CONCLUSION: An annual centre volume of 13 - 16 OARs per year is the optimal threshold associated with the greatest mortality risk reduction after treatment of intact AAA. However, in the current endovascular era, achieving this threshold requires significant re-organisation of OAR practice delivery in many countries, and would affect provision of non-elective aortic services. Low volume centres continuing to offer OAR should aim to achieve mortality results equivalent to the high volume institution benchmark, using validated data from quality registries to track outcomes.

Editor's Choice - International Variations and Sex Disparities in the Treatment of Peripheral Arterial Occlusive Disease: A Report from VASCUNET and the International Consortium of Vascular Registries.

OBJECTIVE: The aim of this study was to determine sex specific differences in the invasive treatment of symptomatic peripheral arterial occlusive disease (PAOD) between member states participating in the VASCUNET and International Consortium of Vascular Registries. METHODS: Data on open surgical revascularisation and peripheral vascular intervention (PVI) of symptomatic PAOD from 2010 to 2017 were collected from population based administrative and registry data from 11 countries. Differences in age, sex, indication, and invasive treatment modality were analysed. RESULTS: Data from 11 countries covering 671 million inhabitants and 1 164 497 hospitalisations (40% women, mean age 72 years, 49% with intermittent claudication, 54% treated with PVI) in Europe (including Russia), North America, Australia, and New Zealand were included. Patient selection and treatment modality varied widely for the proportion of female patients (23% in Portugal and 46% in Sweden), the proportion of patients with claudication (6% in Italy and 69% in Russia), patients' mean age (70 years in the USA and 76 years in Italy), the proportion of octogenarians (8% in Russia and 33% in Sweden), and the proportion of PVI (24% in Russia and 88% in Italy). Numerous differences between females and males were observed in regard to patient age (72 vs. 70 years), the proportion of octogenarians (28% vs. 15%), proportion of patients with claudication (45% vs. 51%), proportion of PVI (57% vs. 51%), and length of hospital stay (7 days vs. 6 days). CONCLUSION: Remarkable differences regarding the proportion of peripheral vascular interventions, patients with claudication, and octogenarians were seen across countries and sexes. Future studies should address the underlying reasons for this, including the impact of national societal guidelines, reimbursement, and differences in health maintenance.

Contemporary Treatment of Popliteal Artery Aneurysms in 14 Countries: A Vascunet Report.

OBJECTIVE: Popliteal artery aneurysm (PAA) is the second most common arterial aneurysm. Vascunet is an international collaboration of vascular registries. The aim was to study treatment and outcomes. METHODS: This was a retrospective analysis of prospectively registered population based data. Fourteen countries contributed data (Australia, Denmark, Finland, France, Hungary, Iceland, Italy, Malta, New Zealand, Norway, Portugal, Serbia, Sweden, and Switzerland). RESULTS: During 2012-2018, data from 10 764 PAA repairs were included. Mean values with between countries ranges in parenthesis are given. The incidence was 10.4 cases/million inhabitants/year (2.4-19.3). The mean age was 71.3 years (66.8-75.3). Most patients, 93.3%, were men and 40.0% were active smokers. The operations were elective in 73.2% (60.0%-85.7%). The mean pre-operative PAA diameter was 32.1 mm (27.3-38.3 mm). Open surgery dominated in both elective (79.5%) and acute (83.2%) cases. A medial surgical approach was used in 77.7%, and posterior in 22.3%. Vein grafts were used in 63.8%. Of the emergency procedures, 91% (n = 2 169, 20.2% of all) were for acute thrombosis and 9% for rupture (n = 236, 2.2% of all). Thrombosis patients had larger aneurysms, mean diameter 35.5 mm, and 46.3% were active smokers. Early amputation and death were higher after acute presentation than after elective surgery (5.0% vs. 0.7%; 1.9% vs. 0.5%). This pattern remained one year after surgery (8.5% vs. 1.0%; 6.1% vs. 1.4%). Elective open compared with endovascular surgery had similar one year amputation rates (1.2% vs. 0.2%; p = .095) but superior patency (84.0% vs. 78.4%; p = .005). Veins had higher patency and lower amputation rates, at one year compared with synthetic grafts (86.8% vs. 72.3%; 1.8% vs. 5.2%; both p < .001). The posterior open approach had a lower amputation rate (0.0% vs. 1.6%, p = .009) than the medial approach. CONCLUSION: Patients presenting with acute ischaemia had high risk of amputation. The frequent use of endovascular repair and prosthetic grafts should be reconsidered based on these results.

Editor's Choice - Assessment of Correlation Between Mean Size of Infrarenal Abdominal Aortic Aneurysm at Time of Intact Repair Against Repair and Rupture Rate in Nine Countries.

OBJECTIVE: This study aimed to analyse the mean abdominal aortic aneurysm (AAA) diameter for repair in nine countries, and to determine variation in mean AAA diameter for elective AAA repair and its relationship to rupture AAA repair rates and aneurysm related mortality in corresponding populations. METHODS: Data on intact (iAAA) and ruptured infrarenal AAA (rAAA) repair for the years 2010-2012 were collected from Denmark, England, Finland, Germany, Hungary, New Zealand, Norway, Sweden, and the USA. The rate of iAAA repair and rAAA per 100 000 inhabitants above 59 years old, mean AAA diameter for iAAA repair and rAAA repair, and the national rates of rAAA were assessed. National cause of death statistics were used to estimate aneurysm related mortality. Direct standardisation methods were applied to the national mortality data. Logistic regression and analysis of variance model adjustments were made for age groups, sex, and year. RESULTS: There was a variation in the mean diameter of iAAA repair (n = 34 566; range Germany = 57 mm, Denmark = 68 mm). The standardised iAAA repair rate per 100000 inhabitants varied from 10.4 (Hungary) to 66.5 (Norway), p<.01, and the standardised rAAA repair rate per 100 000 from 5.8 (USA) to 16.9 (England), p<.01. Overall, there was no significant correlation between mean diameter of iAAA repair and standardised iAAA rate (r2 = 0.04, p = .3). There was no significant correlation between rAAA repair rate (n = 12 628) with mean diameter of iAAA repair (r2 = 0.2, p = .1). CONCLUSION: Despite recommendations from learned society guidelines, data indicate variations in mean diameter for AAA repair. There was no significant correlation between mean diameter of AAA repair and rates of iAAA repair and rAAA repair. These analyses are subject to differences in disease prevalence, uncertainties in rupture rates, validations of vascular registries, causes of death and registrations.

Long-term results after femoral thrombendarterectomy combined with simultaneous endovascular intervention in intermittent claudication and critical ischemia.

OBJECTIVE: This population-based retrospective cohort study investigates long-term results of femoral thrombendarterectomy combined with simultaneous endovascular intervention of the iliac or femoropopliteal vessels, or both, with focus on freedom from recurrent intervention, limb salvage and survival. METHODS: All patients undergoing femoral thrombendarterectomy and simultaneous endovascular intervention between 1999 and 2013 were included. Stratification was according to clinical symptoms, intermittent claudication or critical ischemia, with subgroups for rest pain and ulcer/gangrene, and for type of endovascular intervention, iliac, femoropopliteal or both. We assessed technical success, 30-day complications, freedom from recurrent intervention, survival and amputation free survival in all patients. Limb salvage was assessed in patients with critical ischemia. RESULTS: We identified 151 operations in 143 patients with a total of 164 limbs treated. A total of 13 patients had bilateral and 8 patients had subsequent contralateral operations. Indication was intermittent claudication in 87 (57.6%) and critical ischemia in 64 (42.4%) operations. Thirty-day mortality, only observed in critical ischemia, was 5/64 (7.8%). Freedom from recurrent intervention after 5 years was 91% in intermittent claudication and 70% in critical ischemia. In total, 84% of the patients with claudication were improved at the end of the study. Limb salvage at 5 years was 75% in critical ischemia, 93% in rest pain and 64% in patients with ulcer or gangrene. CONCLUSION: Femoral thrombendarterectomy combined with endovascular iliac or femoropopliteal intervention has good and durable results in intermittent claudication and critical ischemia, especially in patients with rest pain. In most cases, a single operation is sufficient.

Can a Peritoneal Conduit Become an Artery?

OBJECTIVE: Current vascular grafts all have limitations. This study examined peritoneum as a potential graft material and the in vivo transfer of peritoneum into a functional artery like conduit after end to end anastomosis into the common carotid artery of sheep. The aim was to investigate whether implantation of a peritoneal tube into the arterial tree results in a structure with function, histological findings, and gene expression like an artery, and whether such arterialisation occurs through a conversion of the phenotype of peritoneal cells or from host cell migration into the implant. METHODS: Peritoneum with adherent rectus aponeurosis from sheep was used to form tubular vascular grafts that were implanted into the common carotid artery of six sheep, then removed after five months. Two sheep received allogenic peritoneal grafts and four sheep received autologous peritoneal grafts. RESULTS: One sheep died shortly after implantation, so five of the six sheep were followed. Five months after implantation, four of the five remaining grafts were patent. Three of four patent grafts were aneurysmal. The four patent grafts had developed an endothelial layer indistinguishable from that of the adjacent normal artery, and a medial layer with smooth muscle cells with a surrounding adventitia. The new conduit displayed vasomotor function not present at the time of implantation. DNA genotyping showed that the media in the new conduit consisted of recipient smooth muscle cells. Little difference in mRNA expression was demonstrated between the post-implantation conduit and normal artery. CONCLUSION: During a five month implantation period in the arterial system, peritoneum converted into a tissue that histologically and functionally resembled a normal artery, with a functional genetic expression that resembled that of an artery. Single nucleotide polymorphism analysis indicated that this conversion occurs through host cell migration into the graft.

International Validation of the Danish Vascular Registry Karbase: A Vascunet Report.

OBJECTIVES: Vascunet has previously published an international comparison of registry data within vascular surgery. Data validity and completeness in participating registries is essential for a meaningful interpretation of differences between countries. The Vascunet collaboration has therefore developed a methodology for validation of international vascular registry data, previously used for validation of two national registries. This study aimed to assess the internal and external validity of the Danish vascular registry, Karbase, by independent Vascunet validators. METHODS: Three of seven hospitals performing vascular surgery, covering 51% of carotid operations and 78% of abdominal aortic aneurysm (AAA) repairs in Denmark in 2016, were visited by two international validators. Independent evaluation was performed of carotid endarterectomy and AAA repair. Local administrative data were compared with Karbase registry data. External validation compared the numbers of cases in these two systems of data collection. Internal validation compared data accuracy and completeness with individual patient records. RESULTS: Hospital administrative data identified 227/231 carotid and 522/576 abdominal aortic aneurysm (AAA) procedures, whereas Karbase identified 230/231 carotid and 567/576 AAAs. External validity was 99.6% for carotids and 98.4% for AAAs. In internal validation, 1.0% of variables were missing in hospital data whereas 1.7% were missing in Karbase. Data contained within the data fields of Karbase and hospital data were the same in 95.2% (95% CI 91.6-98.8%) for carotids and 97.4% (95% CI 95.4-98.8%) for AAAs. CONCLUSIONS: This study used the Vascunet template for international validation of registry data and demonstrated that Karbase is a reliable system of quality data collection for Danish vascular surgery, especially regarding endpoints. Data quality in the Karbase registry was clearly superior to local administrative data.