Changes in the management of infrarenal abdominal aortic aneurysm disease in Sweden

Trends in AAA Repair in Australia Over Twenty Years

Background

The advent of endovascular techniques has revolutionised the treatment of abdominal aortic aneurysms (AAA). Many countries have seen a transition from open AAA repair (OAR) to endovascular AAA repair (EVAR) over the past 25 years. The only study done in Australia that describes this change was done in the private sector. Majority of healthcare in Australia is delivered through the public, universal healthcare system. The aim of this study was to evaluate the trends in AAA repair in the Australian public sector over the past two decades.

Methods

The Australian Institute of Health and Welfare (AIHW) Procedures Data Cubes from the National Hospitals Data Collection was used to extract data pertaining to AAA repairs from 2000 to 2021. Population data from the Australian Bureau of Statistics was used to calculate incidence of each type of repair per 100,000 population.

Results

There were 65,529 AAA repairs performed in the Australian public sector from 2000 to 2021. EVARs accounted for 64.4% (42,205) and OARs accounted for 35.6% (23, 324) of them. EVAR surpassed OAR as the preferred method of AAA repair in 2006. This trend was observed in both males and females and across all age groups.

Conclusion

There was a consistent and steady transition from OAR to EVAR over the 21 year period with EVAR surpassing OAR as the preferred method of AAA repair relatively early in Australia compared to other countries. Further research that investigates medium- and long-term outcomes of newer stent grafts is needed to further ascertain the continued viability and effectiveness of this trend in AAA treatment.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

German nation-wide in-patient treatment of abdominal aortic aneurysm-trends between 2005 and 2019 and impact of the SARS-CoV-2 pandemic

PURPOSE

Aim of this study was to analyze hospitalizations due to ruptured and non-ruptured abdominal aortic aneurysms (rAAA, nrAAA) in Germany between 2005 and 2021 to determine long-term trends in treatment and the impact of the SARS-CoV-2 pandemic.

MATERIALS AND METHODS

Fully anonymized data were available from the research data center (RDC) of the German Federal Statistical Office (Destatis). All German hospitalizations with the ICD-10 code "I71.3, rAAA" and "I71.4, nrAAA" in 2005 and 2010-2021 were analyzed.

RESULTS

We report data of a total of 202,951 hospitalizations. The number of hospitalizations increased from 2005 to 2019 (14,075 to 16,051, + 14.0%). The rate of open repair (OR) constantly decreased, whereas the rate of endovascular aortic repair (EVAR) increased until 2019. During the pandemic, the number of hospitalizations due to nrAAA dropped from 13,887 (86.5%) in 2019 to 11,278 (85.0%) in 2021. The strongest decrease of hospitalizations for AAA was observed during the first wave of the SARS-CoV-2-pandemic in spring 2020 (-25.5%).

CONCLUSION

Over the past decades, we observed an increasing number of hospitalizations due to AAA accompanied by a shift from OR to EVAR especially for nrAAA. During the lockdown measures due to the SARS-CoV-2-pandemic, a decrease in hospitalizations for nrAAA (but not for rAAA) was shown in 2020 and furthermore in 2021 with no rebound of treatment of nrAAA suggesting an accumulation of untreated AAA with a potentially increased risk of rupture.

Inter-Hospital Transfer of Patients With Ruptured Abdominal Aortic Aneurysm in Switzerland

OBJECTIVE

To analyse the association between inter-hospital transfer and hospital mortality in patients with ruptured abdominal aortic aneurysms (rAAA) in Switzerland.

METHODS

Secondary data analysis of case related hospital discharge data from the Swiss Federal Statistical Office for the years 2009 - 2018. All cases with rAAA as primary or secondary diagnosis were included. Cases with rAAA as a secondary diagnosis without surgical treatment and cases that had been transferred to another hospital without surgical treatment at the referring hospital were excluded. Logistic regression models for hospital mortality were constructed with age, sex, type of admission, van Walraven comorbidity score, type of treatment, insurance class, hospital level, and year of treatment as independent variables.

RESULTS

A total of 1 798 cases with rAAA were treated either surgically (62.5%) or palliatively (37.5%) in Switzerland from 1 January 2009 to 31 December 2018. Of these cases, 72.9% were treated directly (surgically or palliatively) at the hospital of first presentation, whereas 27.1% of all cases with rAAA were transferred between hospitals. The overall crude hospital mortality was 50.3%; being 23.1% in the surgically treated cohort and 95.7% in the palliatively treated cohort. Inter-hospital transfer was associated with better survival compared with patients who were admitted directly (OR 0.52; 95% CI 0.36 - 0.75; p < .001). Treatment in major hospitals was associated with significantly higher mortality rate compared with university hospitals (OR 1.98; 1.41 - 2.79; p < .001). There was no evidence of an association between open repair and hospital mortality (OR 1.06; 0.77 - 1.48; p = .72) compared with endovascular repair.

CONCLUSION

In a healthcare system such as Switzerland's with a highly specialised rescue chain, transfer of haemodynamically stable patients with rAAA is probably safe. In this setting, centralised medical care might outweigh the potential disadvantages of a short delay due to patient transfer. Further studies are needed to address potential confounding factors such as haemodynamic and anatomical features.

Can We Still Teach Open Repair of Abdominal Aortic Aneurysm in The Endovascular Era? Single-Center Analysis on The Evolution of Procedural Characteristics Over 15 Years

OBJECTIVE

In many vascular centers an endovascular first policy for the treatment of abdominal aortic aneurysms (AAA) has resulted in endovascular aortic repair (EVAR) outnumbering open aortic repair (OAR). The declining routine in OAR raises the question whether this might influence procedural outcomes and diminish surgical expertise for current and future vascular surgeons. We aimed to analyze OAR outcomes, AAA morphology and procedural details over the past 15 years while an endovascular first approach was successively implemented.

PARTICICPANTS AND DESIGN

All patients operated for (i)ntact infra-/juxtarenal AAA between January 1, 2005 and December 31, 2019 were identified. Outcome parameters were length of stay (hospital/ICU), in-hospital mortality and medical/surgical complications. Operative details were clamping zone, access and graft configuration. AAA anatomy including neck and iliac parameters was analyzed with Endosize©. Logistic regression, uni- and multivariate analysis were applied.

RESULTS

293 patients received elective OAR for iAAA. Baseline characteristics (age, sex, hypertension, smoking, occlusive disease, coronary disease, hyperlipidemia, diabetes, renal insufficiency and obesity) did not change over time. The number of OAR dropped significantly (-0.5 cases/year p = 0.02). The procedure time (2005-2007: 192.2 ± 87.5min to 2017-2019: 235.6 ± 88.2min; p = 0.0001) and the length of stay (2005-2007: 12.0 ± 7.9 to 2017-2019: 17.0 ± 23.1; p = 0.03) increased significantly, whereas the in-hospital mortality, length of ICU stay and complication rates didn't, nor did AAA anatomy. Upon multivariate analysis, annual number of OAR and any additional anastomosis significantly influenced procedure time, trainee involvement, for example, did not. Hospital length-of-stay depended on patient age (p = 0.002), complication rates (p < 0.0001) and procedure time (p = 0.006).

CONCLUSION

Mortality and complication rates for OAR have remained low and constant. With the increase of EVAR, the absolute number of OARs has decreased significantly. However, the total procedure time has increased and depends significantly on the annual number of OARs in total and per surgeon. This might influence outcome parameters and should be implanted in future surgical education.

Long Term Outcome of Screen Detected Sub-Aneurysmal Aortas in 65 Year Old Men: a Single Scan After Five Years Identifies Those at Risk of Needing AAA Repair

OBJECTIVE

The epidemiology of sub-aneurysmal aortic dilatation (SAA) 25 - 29 mm is not fully understood, and the management of SAA is debated. Lack of evidence is particularly problematic in the screening setting. This study aimed to evaluate the long term outcome of men with screen detected SAAs, focusing on progression to an abdominal aortic aneurysm (AAA), and on the AAAs reaching the threshold diameter for surgical repair.

METHODS

Between 2006 and 2015, all 65 year old men with a screen detected SAA in middle Sweden were re-examined with ultrasound after five and 10 years. The primary outcomes were expansion to AAA ≥ 30 mm and progression to AAA ≥ 55 mm. Secondary outcomes were risk factors for progression, repair rate, and mortality.

RESULTS

A total of 1 020 65 year old men with a SAA were identified, of whom 940 (92.2%; 95% confidence interval 91.0 - 93.8) had follow up. The Kaplan-Meier estimated incidence of AAA ≥ 30 mm development after the five year follow up (which was de facto carried out after a mean of 4.9 years) was 65.8% (61.6 - 69.4), all < 55 mm. The corresponding KM-estimated incidence after the 10 year follow up (carried out after a mean of 11.9 years) was 95.1% (90.1 - 97.4), and 29.7% (18.0 - 39.7) reached ≥ 55 mm. All 41 SAAs eventually expanding to ≥ 55 mm were ≥ 30 mm at the five year follow up. Of these, 32 had surgical repair with 100% survival, six have scheduled repairs, and three (7.3%) were unfit for repair. The KM estimated all cause mortality rates at five and 10 years were 7.0% and 17.9%, respectively, with no proven AAA related deaths.

CONCLUSION

A majority of SAAs eventually progress to an AAA, of which 30% are estimated to eventually reach the threshold for repair within 10 years. A follow up policy with an ultrasound examination after five years can safely and effectively identify those SAAs at risk of developing into clinically significant AAAs needing repair and may be considered for anyone with reasonably good life expectancy.

Editor's Choice - Systematic Review and Meta-Analysis of Sex Specific Differences in Adverse Events After Open and Endovascular Intact Abdominal Aortic Aneurysm Repair: Consistently Worse Outcomes for Women

OBJECTIVE

Previously, reports have shown that women experience a higher mortality rate than men after elective open (OAR) and endovascular (EVAR) repair of abdominal aortic aneurysm (AAA). With recent improvements in overall AAA repair outcomes, this study aimed to identify whether sex specific disparity has been ameliorated by modern practice, and to define sex specific differences in peri- and post-operative complications and pre-operative status; factors which may contribute to poor outcome.

METHODS

This was a systematic review, meta-analysis, and meta-regression of sex specific differences in 30 day mortality and complications conducted according to PRISMA guidance (Prospero registration CRD42020176398). Papers with ≥ 50 women, reporting sex specific outcomes, following intact primary AAA repair, from 2000 to 2020 worldwide were included; with separate analyses for EVAR and OAR. Data sources were Medline, Embase, and CENTRAL databases 2005 - 2020 searched using ProQuest Dialog.

RESULTS

Twenty-six studies (371 215 men, 65 465 women) were included. Meta-analysis and meta-regression indicated that sex specific odds ratios (ORs) for 30 day mortality were unchanged from 2000 to 2020. Mortality risk was higher in women for OAR and more so for EVAR (OR [95% CI] 1.49 [1.37 - 1.61]; 1.86 [1.59 - 2.17], respectively) and this remained following multivariable risk adjustment. Transfusion, pulmonary complications, and bowel ischaemia were more common in women after OAR and EVAR (OAR: ORs 1.81 [1.60 - 2.04], 1.40 [1.28 - 1.53], 1.54 [1.36 - 1.75]; EVAR: ORs 2.18 [2.08 - 2.29] 1.44 [1.17 - 1.77], 1.99 [1.51 - 2.62], respectively). Arterial injury, limb ischaemia, renal and cardiac complications were more common in women after EVAR (ORs 3.02 [1.62 - 5.65], 2.13 [1.48 - 3.06], 1.46 [1.22 - 1.72] and 1.19 [1.03 - 1.37], respectively); the latter was associated with greater mortality risk on meta-regression.

CONCLUSION

Increased mortality risk for women following AAA repair remains. Women had a higher incidence of transfusion, pulmonary and bowel complications after EVAR and OAR. Higher mortality risk ratios for EVAR may result from cardiac complications, additional arterial injury, and embolisation, leading to renal and limb ischaemia. These findings indicate possible causes for observed outcome disparities and targets for quality improvement.

Risk Factors for Abdominal Compartment Syndrome After Endovascular Repair for Ruptured Abdominal Aortic Aneurysm: A Case Control Study

OBJECTIVE

Ruptured abdominal aortic aneurysms (rAAA) are treated by endovascular aneurysm repair (rEVAR) increasingly often. Despite rEVAR being a minimally invasive method, abdominal compartment syndrome (ACS) remains a significant post-operative threat. The aim of this study was to investigate risk factors for ACS after rEVAR, including aortic morphological features.

METHODS

The Swedish vascular registry (Swedvasc) was assessed for ACS after rEVAR in the period 2008 - 2015. All patients identified were compared with controls (i.e., patients who did not develop ACS after rEVAR), matched by centre and repair date. Case records were reviewed, and radiology images analysed in a core laboratory. Comparisons were performed with respect to physiological and radiological risk factors.

RESULTS

The study population consisted of 40 patients with ACS and 68 controls. Pre-operatively, patients with ACS had a lower blood pressure (BP) than controls (median 70 mmHg vs. 97 mmHg; p < .001). Intra-operatively, they had aortic balloon occlusion more often (55.0% vs. 10.3%; p < .001) and received more transfusions than controls (median nine units of packed red blood cells [pRBC] vs. two units; p < .001). Ninety-seven per cent of those who developed ACS had a pre-operative BP < 70 mmHg, aortic balloon occlusion, or received more than five pRBC unit transfusions. Treatment outside the instructions for use did not differ between patients and controls (57.5% vs. 54.4%; p = .84), and neither did the pre-operative patency of the inferior mesenteric artery (57.1% vs. 63.9%; p = .52) nor the number of visible lumbar arteries on pre-operative imaging (2 vs. 4; p = .014). In multivariable logistic regression, the number of intra-operative transfusions were predictive of ACS (p < .001), while pre-operative hypotension (p = .32) and aortic balloon occlusion (p = .018) were not.

CONCLUSION

ACS after rEVAR is mainly associated with physiological factors and is unlikely to develop without the presence of a pre-operative BP < 70 mmHg, the need for an aortic occlusion balloon, or more than five intra-operative pRBC unit transfusions. Treatment outside the IFU or any other morphological factor were not associated with a risk of ACS.

Open versus Endovascular Abdominal Aortic Aneurysm Repair in the Australian Private Sector Over Twenty Years

PURPOSE

Over the past two decades, the proliferation of endovascular surgery has changed the approach to abdominal aortic aneurysm (AAA) repair. In Australia, close to two-thirds of surgical procedures are performed in the private healthcare system. We aimed to describe the trends in AAA repair in the Australian private sector throughout the early 21st century.

MATERIALS AND METHODS

Medicare Benefits Schedule (MBS) statistics were accessed to determine the number of infrarenal open AAA repair (OAR) and endovascular AAA repair (EVAR) procedures performed between January 2000 and December 2019. Population data were extracted from the Australian Bureau of Statistics and used to calculate incidence per 100,000 population. Further analysis was performed according to age, gender, and state.

RESULTS

During the study period, 13,193 (67.0%) EVARs and 6504 (33.0%) OARs were performed in the Australian private sector. OARs fell from 70.5% (n=567) of AAA repairs in 2000 to 15.7% (n=237) in 2019, while EVARs rose from 29.5% (n=151) to 84.3% (n=808). The frequency of EVAR surpassed OAR in 2004. The overall incidence of AAA repair varied minimally over the time period (range: 4.9-6.5 per 100,000 adults per year). AAA repair was more common in males than females (9.7 vs 1.7 per 100,000 population) and more common in older age groups. There was a 4-fold increase in EVAR among males older than 85 years (12.8-57.4 per 100,000 population), the largest rise of any group. The overall EVAR:OAR ratio increased from 0.4 to 5.4. There were considerable state-based discrepancies.

CONCLUSION

The landscape of AAA repair in Australian private sector has drastically changed with a clear preference toward EVAR. EVAR saw increased use across all genders, age groups and states, despite stable rates of AAA surgery. Further research is necessary to compare our findings to national trends in the Australian public sector.

Effects of hospital preference for endovascular repair on postoperative mortality after elective abdominal aortic aneurysm repair: analysis of the Dutch Surgical Aneurysm Audit

BACKGROUND

Increased use of endovascular aneurysm repair (EVAR) and reduced open surgical repair (OSR), has decreased postoperative mortality after elective repair of abdominal aortic aneurysms (AAAs). The choice between EVAR or OSR depends on aneurysm anatomy, and the experience and preference of the vascular surgeon, and therefore differs between hospitals. The aim of this study was to investigate the current mortality risk difference (RD) between EVAR and OSR, and the effect of hospital preference for EVAR on overall mortality.

METHODS

Primary elective infrarenal or juxtarenal aneurysm repairs registered in the Dutch Surgical Aneurysm Audit (2013-2017) were analysed. First, mortality in hospitals with a higher preference for EVAR (high-EVAR group) was compared with that in hospitals with a lower EVAR preference (low-EVAR group), divided by the median percentage of EVAR. Second, the mortality RD between EVAR and OSR was determined by unadjusted and adjusted linear regression and propensity-score (PS) analysis and then by instrumental-variable (IV) analysis, adjusting for unobserved confounders; percentage EVAR by hospital was used as the IV.

RESULTS

A total of 11 997 patients were included. The median hospital rate of EVAR was 76.6 per cent. The overall mortality RD between high- and low-EVAR hospitals was 0.1 (95 per cent -0.5 to 0.4) per cent. The OSR mortality rate was significantly higher among high-EVAR hospitals than low-EVAR hospitals: 7.3 versus 4.0 per cent (RD 3.3 (1.4 to 5.3) per cent). The EVAR mortality rate was also higher in high-EVAR hospitals: 0.9 versus 0.7 per cent (RD 0.2 (-0.0 to 0.6) per cent). The RD following unadjusted, adjusted, and PS analysis was 4.2 (3.7 to 4.8), 4.4 (3.8 to 5.0), and 4.7 (4.1 to 5.3) per cent in favour of EVAR over OSR. However, the RD after IV analysis was not significant: 1.3 (-0.9 to 3.6) per cent.

CONCLUSION

Even though EVAR has a lower mortality rate than OSR, the overall effect is offset by the high mortality rate after OSR in hospitals with a strong focus on EVAR.

Nineteen-year outcomes with the Anaconda stent graft system from two tertiary centers

OBJECTIVE

The Anaconda stent graft device presents peculiar and unique features in its design and deployment sequence, available on the market for many years with minor modifications, among different generations. The aim of this study was to assess the long-term, real-life, outcomes obtained in two high-volume centers with this endograft for infrarenal aortic aneurysms treatment over a period of 19 years.

METHODS

All patients treated with the investigated device between 2000 and 2019, with at least 1 year of follow-up, were entered into a prospective database and data were reviewed retrospectively. The long-term results were assessed according to the Kaplan-Meier method. Primary outcomes were overall survival, freedom from AAA rupture, and freedom from AAA-related death. Secondary outcomes were freedom from late reintervention, freedom from late conversion to open repair, freedom from late limb occlusion, and freedom from late EVAR failure.

RESULTS

A total of 260 consecutive patients were treated during the study period. Technical success was achieved in 98.5% (256/260) of the cases. Two perioperative deaths (0.8%) and four major complications (1.5%) were recorded. At a mean follow-up of 54 ± 38 months (summary follow-up index = 0.86), the late survival estimate was 94.8% at 1 year, 75.2% at 5 years, 50.5% at 10 years, and 43.3% at 13 years, with no case of late AAA rupture or late AAA-related death. Late freedom from conversion was 99.2% at 1 year, 96.9% at 5 years, 94.0% at 10 years, and 94.0% at 13 years. Freedom from late limb thrombosis was 96.8% at 1 year and 91.0% at 5, 10, and 13 years. Estimates of freedom from late reintervention was 95.6% at 1 year, 87.0% at 5 years, 77.4% at 10 years, and 77.4% at 13 years. Estimates of limb thrombosis at 11 years were significantly different in patients receiving or not intraoperative iliac kissing balloon maneuver with noncompliant angioplasty catheters (98.0% vs 88.4%; P = .029).

CONCLUSIONS

The Anaconda stent graft demonstrated effective and durable outcomes for AAA treatment over a 19-year period, with no case of late AAA rupture or AAA related death in the studied population. Late limb occlusion was the leading cause of reintervention; however, a positive prevention strategy was found in intraoperative kissing balloon, which was associated with significant reduced rate of iliac thrombosis over time.

Screening women aged 65 years or over for abdominal aortic aneurysm: a modelling study and health economic evaluation

BACKGROUND

Abdominal aortic aneurysm (AAA) screening programmes have been established for men in the UK to reduce deaths from AAA rupture. Whether or not screening should be extended to women is uncertain.

OBJECTIVE

To evaluate the cost-effectiveness of population screening for AAAs in women and compare a range of screening options.

DESIGN

A discrete event simulation (DES) model was developed to provide a clinically realistic model of screening, surveillance, and elective and emergency AAA repair operations. Input parameters specifically for women were employed. The model was run for 10 million women, with parameter uncertainty addressed by probabilistic and deterministic sensitivity analyses.

SETTING

Population screening in the UK.

PARTICIPANTS

Women aged ≥ 65 years, followed up to the age of 95 years.

INTERVENTIONS

Invitation to ultrasound screening, followed by surveillance for small AAAs and elective surgical repair for large AAAs.

MAIN OUTCOME MEASURES

Number of operations undertaken, AAA-related mortality, quality-adjusted life-years (QALYs), NHS costs and cost-effectiveness with annual discounting.

DATA SOURCES

AAA surveillance data, National Vascular Registry, Hospital Episode Statistics, trials of elective and emergency AAA surgery, and the NHS Abdominal Aortic Aneurysm Screening Programme (NAAASP).

REVIEW METHODS

Systematic reviews of AAA prevalence and, for elective operations, suitability for endovascular aneurysm repair, non-intervention rates, operative mortality and literature reviews for other parameters.

RESULTS

The prevalence of AAAs (aortic diameter of ≥ 3.0 cm) was estimated as 0.43% in women aged 65 years and 1.15% at age 75 years. The corresponding attendance rates following invitation to screening were estimated as 73% and 62%, respectively. The base-case model adopted the same age at screening (65 years), definition of an AAA (diameter of ≥ 3.0 cm), surveillance intervals (1 year for AAAs with diameter of 3.0-4.4 cm, 3 months for AAAs with diameter of 4.5-5.4 cm) and AAA diameter for consideration of surgery (5.5 cm) as in NAAASP for men. Per woman invited to screening, the estimated gain in QALYs was 0.00110, and the incremental cost was £33.99. This gave an incremental cost-effectiveness ratio (ICER) of £31,000 per QALY gained. The corresponding incremental net monetary benefit at a threshold of £20,000 per QALY gained was -£12.03 (95% uncertainty interval -£27.88 to £22.12). Almost no sensitivity analyses brought the ICER below £20,000 per QALY gained; an exception was doubling the AAA prevalence to 0.86%, which resulted in an ICER of £13,000. Alternative screening options (increasing the screening age to 70 years, lowering the threshold for considering surgery to diameters of 5.0 cm or 4.5 cm, lowering the diameter defining an AAA in women to 2.5 cm and lengthening the surveillance intervals for the smallest AAAs) did not bring the ICER below £20,000 per QALY gained when considered either singly or in combination.

LIMITATIONS

The model for women was not directly validated against empirical data. Some parameters were poorly estimated, potentially lacking relevance or unavailable for women.

CONCLUSION

The accepted criteria for a population-based AAA screening programme in women are not currently met.

FUTURE WORK

A large-scale study is needed of the exact aortic size distribution for women screened at relevant ages. The DES model can be adapted to evaluate screening options in men.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42015020444 and CRD42016043227.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

The Nellix endovascular aneurysm sealing system: current perspectives

Background

The Nellix endovascular aneurysm sealing (EVAS) system is a novel approach for the treatment of abdominal aortic aneurysm (AAA). We aimed to evaluate the efficacy of EVAS in the management of patients with AAA.

Materials and methods

We searched PubMed/MEDLINE, CINAHL, and bibliographic reference lists to identify studies reporting clinical outcomes in patients with asymptomatic, non-ruptured AAA treated with EVAS with the Nellix device. We pooled dichotomous outcome data using random-effects models.

Results

We identified 14 single-arm observational studies, reporting a total of 1,510 patients. The pooled estimate of technical success was 99% (95% CI =98–100; heterogeneity: P=0.869, I²=0%). Adjunctive procedures were carried out in 39% (95% CI =19–63; heterogeneity: P<0.0001, I²=88%). Two cases of aneurysm rupture were reported within 30 days of treatment (0.7%, 95% CI =0.3–1.6; heterogeneity: P=0.923, I²=0%) and another five cases of rupture occurred during follow-up (0.8%, 95% CI =0.4–1.6; heterogeneity: P=0.958, I²=0%). The pooled estimates of early (within 30 days) and late (during follow-up) type I endoleak were 2.8 % (95% CI =1.8–4.2; heterogeneity: P=0.254, I²=18%) and 1.9% (95% CI =1.3–2.8; heterogeneity: P=0.887, I²=0%), respectively. Sac enlargement was noted in 3.1% (95% CI =1.8–5.4; heterogeneity: P=0.419, I²=0%) and device migration in 2.1% (95% CI =0.8–5.3; heterogeneity: P=0.004, I²=65%). The early and late reintervention rates were 2.7% (95% CI =1.7–4.2; heterogeneity: P=0.183, I²=27%) and 3.5% (95% CI =2.3–5.5; heterogeneity: P=0.061, I²=42%), respectively. The pooled estimate of 30-day mortality was 1.5% (95% CI =0.9–2.6; heterogeneity: P=0.559, I²=0%) and the pooled estimate of aneurysm-related death during follow-up was 1.0% (95% CI =0.6–1.9; heterogeneity: P=0.872, I²=0%).

Conclusion

Reported outcomes of EVAS are acceptable. Type I endoleak, sac enlargement, device migration, and aneurysm rupture are recognized complications. High-level research is required to investigate potential advantages of EVAS over conventional treatments.

Incidence, Treatment and Mortality in Patients with Abdominal Aortic Aneurysms

BACKGROUND

Aim of this study was to analyze hospital incidence, type of treatment, and hospital mortality rates of patients with abdominal aortic aneurysm (AAA) in Germany from 2005 to 2014.

METHODS

Microdata of the diagnosis-related group (DRG) statistics compiled by the German Federal Statistical Office for the years 2005-2014 were analyzed. Patients who were hospitalized for a ruptured AAA (rAAA, ICD-10 code I71.3, treated either surgically or conservatively) or received surgical treatment for an unruptured AAA (nrAAA, ICD-10-Code I71.4, treated either with open surgery or an endovascular procedure) were included in the analysis. The "European Standard Population 2013" was used for direct standardization of the hospital incidences. In-hospital mortality was calculated with standardization for age and risk.

RESULTS

The standardized overall hospital incidence of AAA was 27.9 and 3.3 cases per 100 000 people for men and women, respectively; over the period of the study, the incidence of rAAA fell by 30% in both sexes and that of nrAAA rose by 16% in men and 42% in women. The percentage of patients receiving endovascular treatment rose from 29% to 75% in patients with nrAAA and from 8% to 36% in patients with rAAA. The age- and risk-standardized in-hospital mortality of nrAAA was 3.3% in men and 5.3% in women. The in-hospital mortality of surgically treated rAAA was 39% in men and 48% in women.

CONCLUSION

The hospital incidence of AAA rose from 2005 to 2014, while that of rAAA fell. Endovascular treatment became more common for nrAAA as well as rAAA, and in-hospital mortality fell for both.

Follow-up after endovascular aortic aneurysm repair can be stratified based on first postoperative imaging

Background

Lifelong postoperative surveillance is recommended following endovascular aneurysm repair (EVAR). Although the purpose is to prevent and/or identify complications early, it also results in increased cost and workload. This study was designed to examine whether it may be possible to identify patients at low risk of complications based on their first postoperative CT angiogram (CTA).

Methods

All patients undergoing EVAR in two Swedish centres between 2001 and 2012 were identified retrospectively and categorized based on the first postoperative CTA as at low risk (proximal and distal sealing zone at least 10 mm and no endoleak) or high risk (sealing zone less than 10 mm and/or presence of any endoleak) of complications.

Results

Some 326 patients (273 men) with a CTA performed less than 1 year after EVAR were included (low risk 212, 65·0 per cent; high risk 114, 35·0 per cent). There was no difference between the groups in terms of sex, age, co-morbidities, abdominal aortic aneurysm (AAA) diameter, preoperative AAA neck anatomy, stent-graft type or duration of follow-up (mean(s.d.) 4·8(3·2) years). Five-year freedom from AAA-related adverse events was 97·1 and 47·7 per cent in the low- and high-risk groups respectively (P &lt; 0·001). The corresponding freedom from AAA-related reintervention was 96·2 and 54·1 per cent (P &lt; 0·001). The method had a sensitivity of 88·3 per cent, specificity of 77·0 per cent and negative predictive value of 96·6 per cent to detect AAA-related adverse events. The number of surveillance imaging per AAA-related adverse event was 168 versus 11 for the low-risk versus high-risk group.

Conclusion

Two-thirds of patients undergoing EVAR have an adequate seal and no endoleak on the first postoperative CTA, and a very low risk of AAA-related events up to 5 years. Less vigilant follow-up after EVAR may be considered for these patients.

Editor's Choice - The Impact of Centralisation and Endovascular Aneurysm Repair on Treatment of Ruptured Abdominal Aortic Aneurysms Based on International Registries

OBJECTIVES

Current management of ruptured abdominal aortic aneurysms (RAAA) varies among centres and countries, particularly in the degree of implementation of endovascular aneurysm repair (EVAR) and levels of vascular surgery centralisation. This study assesses these variations and the impact they have on outcomes.

MATERIALS AND METHODS

RAAA repairs from vascular surgical registries in 11 countries, 2010-2013, were investigated. Data were analysed overall, per country, per treatment modality (EVAR or open aortic repair [OAR]), centre volume (quintiles IV), and whether centres were predominantly EVAR (≥50% of RAAA performed with EVAR [EVAR(p)]) or predominantly OAR [OAR(p)]. Primary outcome was peri-operative mortality. Data are presented as either mean values or percentages with 95% CI within parentheses, and compared with chi-square tests, as well as with adjusted OR.

RESULTS

There were 9273 patients included. Mean age was 74.7 (74.5-74.9) years, and 82.7% of patients were men (81.9-83.6). Mean AAA diameter at rupture was 7.6 cm (7.5-7.6). Of these aneurysms, 10.7% (10.0-11.4) were less than 5.5 cm. EVAR was performed in 23.1% (22.3-24.0). There were 6817 procedures performed in OAR(p) centres and 1217 performed in EVAR(p) centres. Overall peri-operative mortality was 28.8% (27.9-29.8). Peri-operative mortality for OAR was 32.1% (31.0-33.2) and for EVAR 17.9% (16.3-19.6), p < .001, and the adjusted OR was 0.38 (0.31-0.47), p < .001. The peri-operative mortality was 23.0% in EVAR(p) centres (20.6-25.4), 29.7% in OAR(p) centres (28.6-30.8), p < .001; adjusted OR = 0.60 (0.46-0.78), p < .001. Peri-operative mortality was lower in the highest volume centres (QI > 22 repairs per year), 23.3% (21.2-25.4) than in QII-V, 30.0% (28.9-31.1), p < .001. Peri-operative mortality after OAR was lower in high volume centres compared with the other centres, 25.3% (23.0-27.6) and 34.0% (32.7-35.4), respectively, p < .001. There was no significant difference in peri-operative mortality after EVAR between centres based on volume.

CONCLUSIONS

Peri-operative mortality is lower in centres with a primary EVAR approach or with high case volume. Most repairs, however, are still performed in low volume centres and in centres with a primary OAR strategy. Reorganisation of acute vascular surgical services may improve outcomes of RAAA repair.

The UK EndoVascular Aneurysm Repair (EVAR) randomised controlled trials: long-term follow-up and cost-effectiveness analysis

BACKGROUND

Short-term survival benefits of endovascular aneurysm repair (EVAR) compared with open repair (OR) of intact abdominal aortic aneurysms have been shown in randomised trials, but this early survival benefit is soon lost. Survival benefit of EVAR was unclear at follow-up to 10 years.

OBJECTIVE

To assess the long-term efficacy of EVAR against OR in patients deemed fit and suitable for both procedures (EVAR trial 1; EVAR-1); and against no intervention in patients unfit for OR (EVAR trial 2; EVAR-2). To appraise the long-term significance of type II endoleak and define criteria for intervention.

DESIGN

Two national, multicentre randomised controlled trials: EVAR-1 and EVAR-2.

SETTING

Patients were recruited from 37 hospitals in the UK between 1 September 1999 and 31 August 2004.

PARTICIPANTS

Men and women aged ≥ 60 years with an aneurysm of ≥ 5.5 cm (as identified by computed tomography scanning), anatomically suitable and fit for OR were randomly assigned 1 : 1 to either EVAR (n = 626) or OR (n = 626) in EVAR-1 using computer-generated sequences at the trial hub. Patients considered unfit were randomly assigned to EVAR (n = 197) or no intervention (n = 207) in EVAR-2. There was no blinding.

INTERVENTIONS

EVAR, OR or no intervention.

MAIN OUTCOME MEASURES

The primary end points were total and aneurysm-related mortality until mid-2015 for both trials. Secondary outcomes for EVAR-1 were reinterventions, costs and cost-effectiveness.

RESULTS

In EVAR-1, over a mean of 12.7 years (standard deviation 1.5 years; maximum 15.8 years), we recorded 9.3 deaths per 100 person-years in the EVAR group and 8.9 deaths per 100 person-years in the OR group [adjusted hazard ratio (HR) 1.11, 95% confidence interval (CI) 0.97 to 1.27; p = 0.14]. At 0-6 months after randomisation, patients in the EVAR group had a lower mortality (adjusted HR 0.61, 95% CI 0.37 to 1.02 for total mortality; HR 0.47, 95% CI 0.23 to 0.93 for aneurysm-related mortality; p = 0.031), but beyond 8 years of follow-up patients in the OR group had a significantly lower mortality (adjusted HR 1.25, 95% CI 1.00 to 1.56, p = 0.048 for total mortality; HR 5.82, 95% CI 1.64 to 20.65, p = 0.0064 for aneurysm-related mortality). The increased aneurysm-related mortality in the EVAR group after 8 years was mainly attributable to secondary aneurysm sac rupture, with increased cancer mortality also observed in the EVAR group. Overall, aneurysm reintervention rates were higher in the EVAR group than in the OR group, 4.1 and 1.7 per 100 person-years, respectively (p < 0.001), with reinterventions occurring throughout follow-up. The mean difference in costs over 14 years was £3798 (95% CI £2338 to £5258). Economic modelling based on the outcomes of the EVAR-1 trial showed that the cost per quality-adjusted life-year gained over the patient's lifetime exceeds conventional thresholds used in the UK. In EVAR-2, patients died at the same rate in both groups, but there was suggestion of lower aneurysm mortality in those who actually underwent EVAR. Type II endoleak itself is not associated with a higher rate of mortality.

LIMITATIONS

Devices used were implanted between 1999 and 2004. Newer devices might have better results. Later follow-up imaging declined, particularly for OR patients. Methodology to capture reinterventions changed mainly to record linkage through the Hospital Episode Statistics administrative data set from 2009.

CONCLUSIONS

EVAR has an early survival benefit but an inferior late survival benefit compared with OR, which needs to be addressed by lifelong surveillance of EVAR and reintervention if necessary. EVAR does not prolong life in patients unfit for OR. Type II endoleak alone is relatively benign.

FUTURE WORK

To find easier ways to monitor sac expansion to trigger timely reintervention.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN55703451.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and the results will be published in full in Health Technology Assessment; Vol. 22, No. 5. See the NIHR Journals Library website for further project information.

Textbook Outcome: A Composite Measure for Quality of Elective Aneurysm Surgery

OBJECTIVE

To investigate a new composite quality measurement, which comprises a desirable outcome for elective aneurysm surgery, called "Textbook Outcome" (TO).

BACKGROUND

Single-quality indicators in vascular surgery are often not distinctive and insufficiently reflect the quality of care.

METHODS

All patients undergoing elective abdominal aortic aneurysm repair, registered in the Dutch Surgical Aneurysm Audit between 2014 and 2015 were included. TO was defined as the percentage of patients who had abdominal aortic aneurysm-repair without intraoperative complications, postoperative surgical complications, reinterventions, prolonged hospital stay [endovascular aneurysm repair (EVAR) ≤4 d, open surgical repair (OSR) ≤10 d], readmissions, and postoperative mortality (≤30 d after surgery/at discharge). Case-mix adjusted TO rates were used to compare hospitals and to compare individual hospital results for different procedures.

RESULTS

Five thousand one hundred seventy patients were included, of whom 4039 were treated with EVAR and 1131 with OSR. TO was achieved in 71% of EVAR and 53% of OSR. Important obstacles for achieving TO were a prolonged hospital stay, postoperative complications, and readmissions. Adjusted TO rates varied from 38% to 89% (EVAR) and from 0% to 97% (OSR) between individual hospitals. Hospitals with a high TO for OSR also had a high TO for EVAR; however, a high TO for EVAR did not implicate a high TO for OSR.

CONCLUSIONS

TO generates additional information to evaluate the overall quality of the care of elective aneurysm surgery, which subsequently can be used by hospitals to improve the quality of their care.

Morphological suitability for endovascular repair, non-intervention rates, and operative mortality in women and men assessed for intact abdominal aortic aneurysm repair: systematic reviews with meta-analysis

BACKGROUND

Prognosis for women with abdominal aortic aneurysm might be worse than the prognosis for men. We aimed to systematically quantify the differences in outcomes between men and women being assessed for repair of intact abdominal aortic aneurysm using data from study periods after the year 2000.

METHODS

In these systematic reviews and meta-analysis, we identified studies (randomised, cohort, or cross-sectional) by searching MEDLINE, Embase, CENTRAL, and grey literature published between Jan 1, 2005, and Sept 2, 2016, for two systematic reviews and Jan 1, 2009, and Sept 2, 2016, for one systematic review. Studies were included if they were of both men and women, with data presented for each sex separately, with abdominal aortic aneurysms being assessed for aneurysm repair by either endovascular repair (EVAR) or open repair. We conducted three reviews based on whether studies reported the proportion morphologically suitable (within manufacturers' instructions for use) for EVAR (EVAR suitability review), non-intervention rates (non-intervention review), and 30-day mortality (operative mortality review) after intact aneurysm repair. Studies had to include at least 20 women (for the EVAR suitability review), 20 women (for the non-intervention review), and 50 women (for the operative mortality review). Studies were excluded if they were review articles, editorials, letters, or case reports. For the operative review, studies were also excluded if they only provided hazard ratios or only reported in-hospital mortality. We assessed the quality of the studies using the Newcastle-Ottawa scoring system, and contacted authors for the provision of additional data if needed. We combined results across studies by random-effects meta-analysis. This study is registered with PROSPERO, number CRD42016043227.

FINDINGS

Five studies assessed the morphological eligibility for EVAR (1507 men, 400 women). The overall pooled proportion of women eligible (34%) for EVAR was lower than it was in men (54%; odds ratio [OR] 0·44, 95% CI 0·32-0·62). Four single-centre studies reported non-intervention rates (1365 men, 247 women). The overall pooled non-intervention rates were higher in women (34%) than men (19%; OR 2·27, 95% CI 1·21-4·23). The review of 30-day mortality included nine studies (52 018 men, 11 076 women). The overall pooled estimate for EVAR was higher in women (2·3%) than in men (1·4%; OR 1·67, 95% CI 1·38-2·04). The overall estimate for open repair also was higher in women (5·4%) than in men (2·8%; OR 1·76, 95% CI 1·35-2·30).

INTERPRETATION

Compared with men, a smaller proportion of women are eligible for EVAR, a higher proportion of women are not offered intervention, and operative mortality is much higher in women for both EVAR and open repair. The management of abdominal aortic aneurysm in women needs improvement.

FUNDING

National Institute for Health Research (UK).

Editor's Choice - Prolonged ICU Length of Stay after AAA Repair: Analysis of Time Trends and Long-term Outcome

OBJECTIVE

The aim of the study was to investigate the frequency and outcome of prolonged intensive care unit (ICU) length of stay (LOS) after abdominal aortic aneurysm (AAA) repair in the endovascular era.

METHODS

All patients operated on for AAA between 1999 and 2013 at Uppsala University hospital were identified. Data were retrieved from the Swedish Vascular registry, the Swedish Intensive Care registry, the National Population registry, and case records. Prolonged ICU LOS was defined as ≥ 48 h during the primary hospital stay. Patients surviving ≥ 48 h after AAA surgery were included in the analysis.

RESULTS

A total of 725 patients were identified, of whom 707 (97.5%) survived ≥ 48 h; 563 (79.6%) underwent intact AAA repair and 144 (20.4%) ruptured AAA repair. A total of 548 patients (77.5%) required < 48 h of intensive care, 115 (16.3%) 2-6 days and 44 (6.2%) ≥ 7 days. The rate of prolonged ICU LOS declined considerably over time, from 41.4% of all AAA repairs in 1999 to 7.3% in 2013 (p < .001) whereas the use of endovascular aortic repair (EVAR) increased from 6.9% in 1999 to 78.0% in 2013 (p < .001). The 30 day survival rate was 98.2% for those with < 48 h ICU stay versus 93.0% for 2-6 days versus 81.8% for ≥ 7 days (p < .001); the corresponding 90 day survival was 97.1% versus 86.1% versus 63.6% (p < .001) respectively. For patients surviving 90 days after repair, there was no difference in long-term survival between the groups.

CONCLUSION

During the period of progressively increasing use of EVAR, a simultaneous significant reduction in frequency of prolonged ICU LOS occurred. Although prolonged ICU LOS was associated with a high short-term mortality, long-term outcome among those surviving the initial 90 days was less affected.

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.

Editor's Choice - Trend-break in Abdominal Aortic Aneurysm Repair With Decreasing Surgical Workload

BACKGROUND

The epidemiology and management of abdominal aortic aneurysms (AAAs) has changed drastically in the past decades, with implementation of nationwide screening programs, introduction of endovascular repair (EVAR), and reduced prevalence of the disease. This report aims to assess recent trends in AAA repair epidemiology in Sweden in this context.

METHODS

Primary AAA repairs registered in the nationwide Swedish Vascular Registry (Swedvasc) 1994-2014 were analyzed regarding patient characteristics, repair incidence, technique, and outcome. Four time periods were compared: 1994-1999, 2000-2004, 2005-2009, and 2010-2014.

RESULT

The incidence of intact AAA repair increased (18.4/100,000 1994-1999, 27.3/100,000 2010-2014, p < .001) predominantly among octogenarians (12.7/100,000 1994-1999, 36.0/100,000 2010-2014, p < .001). The utilization of EVAR increased (58% of all intact AAA repairs 2010-2014), especially among octogenarians (80% 2010-2014). During the last time period, however, the incidence of intact AAA repair stabilized, despite an increasing number of screening-detected AAAs operated on (19% in 2010-2014). Short- and long-term outcome after intact AAA repair continued to improve, most pronounced among octogenarians (30-day mortality 9% 1994-1999, 2% 2010-2014, p < .001). The incidence of ruptured AAA repair steadily decreased (9.2/100,000 1994-1999, 6.9/100,000 2010-2014, p < .001) and the use of EVAR for ruptures increased (30% in 2010-2014). The previously observed improvement of short- and long-term outcome after ruptured AAA repair (30-day mortality 38% 1994-1999, 28% 2010-2014, p < .001) stalled during the last time period. The overall 30-day mortality after ruptured AAA repair was 22% after EVAR versus 31% after open repair in 2010-2014. The corresponding mortality for octogenarians was 28% versus 42%.

CONCLUSIONS

For the first time, a halt in intact AAA repair workload could be identified. This trend-break occurred despite continued increase in treatment of octogenarians and screening-detected aneurysms. Additionally, the ruptured AAA repair incidence continued to decrease. These findings, together with the sustained improvement in survival after AAA repair, may have important impact on planning of vascular surgical services.

Meta-analysis of individual-patient data from EVAR-1, DREAM, OVER and ACE trials comparing outcomes of endovascular or open repair for abdominal aortic aneurysm over 5 years

BACKGROUND

The erosion of the early mortality advantage of elective endovascular aneurysm repair (EVAR) compared with open repair of abdominal aortic aneurysm remains without a satisfactory explanation.

METHODS

An individual-patient data meta-analysis of four multicentre randomized trials of EVAR versus open repair was conducted to a prespecified analysis plan, reporting on mortality, aneurysm-related mortality and reintervention.

RESULTS

The analysis included 2783 patients, with 14 245 person-years of follow-up (median 5·5 years). Early (0-6 months after randomization) mortality was lower in the EVAR groups (46 of 1393 versus 73 of 1390 deaths; pooled hazard ratio 0·61, 95 per cent c.i. 0·42 to 0·89; P = 0·010), primarily because 30-day operative mortality was lower in the EVAR groups (16 deaths versus 40 for open repair; pooled odds ratio 0·40, 95 per cent c.i. 0·22 to 0·74). Later (within 3 years) the survival curves converged, remaining converged to 8 years. Beyond 3 years, aneurysm-related mortality was significantly higher in the EVAR groups (19 deaths versus 3 for open repair; pooled hazard ratio 5·16, 1·49 to 17·89; P = 0·010). Patients with moderate renal dysfunction or previous coronary artery disease had no early survival advantage under EVAR. Those with peripheral artery disease had lower mortality under open repair (39 deaths versus 62 for EVAR; P = 0·022) in the period from 6 months to 4 years after randomization.

CONCLUSION

The early survival advantage in the EVAR group, and its subsequent erosion, were confirmed. Over 5 years, patients of marginal fitness had no early survival advantage from EVAR compared with open repair. Aneurysm-related mortality and patients with low ankle : brachial pressure index contributed to the erosion of the early survival advantage for the EVAR group. Trial registration numbers: EVAR-1, ISRCTN55703451; DREAM (Dutch Randomized Endovascular Aneurysm Management), NCT00421330; ACE (Anévrysme de l'aorte abdominale, Chirurgie versus Endoprothèse), NCT00224718; OVER (Open Versus Endovascular Repair Trial for Abdominal Aortic Aneurysms), NCT00094575.

Outcomes of surgery for patients with Behcet's disease causing aortic pseudoaneurysm: a shift from open surgery to endovascular repair

OBJECTIVES

Behcet's disease is a form of systematic vasculitis that affects vessels of various sizes. Aortic pseudoaneurysm is one of the most important causes of death among patients with Behcet's disease due to its high risk of rupture and associated mortality. Our study aimed to investigate the outcomes of Behcet's disease patients with aortic pseudoaneurysms undergoing open surgery and endovascular aortic repair.

METHODS

From January 2003 to September 2014, ten consecutive patients undergoing surgery for aortic pseudoaneurysm met the diagnostic criteria for Behcet's disease. Endovascular repair was the preferred modality and open surgery was performed as an alternative. Systemic immunosuppressive medication was administered after Behcet's disease was definitively diagnosed.

RESULTS

Eight patients initially underwent endovascular repair and two patients initially underwent open surgery. The overall success rate was 90% and the only failed case involved the use of the chimney technique to reach a suprarenal location. The median follow-up duration was 23 months. There were 7 recurrences in 5 patients. The median interval between operation and recurrence was 13 months. No significant risk factors for recurrence were identified, but a difference in recurrence between treatment and non-treatment with preoperative immunosuppressive medication preoperatively was notable. Four aneurysm-related deaths occurred within the follow-up period. The overall 1-year, 3-year and 5-year survival rates were 80%, 64% and 48%, respectively.

CONCLUSIONS

Both open surgery and endovascular repair are safe and effective for treating aortic pseudoaneurysm in Behcet's disease patients. The results from our retrospective study indicated that immunosuppressive medication was essential to defer the occurrence and development of recurrent aneurysms.

Editor's Choice - Abdominal Compartment Syndrome After Surgery for Abdominal Aortic Aneurysm: A Nationwide Population Based Study

OBJECTIVE/BACKGROUND

The understanding of abdominal compartment syndrome (ACS), and its importance for outcome, has increased over time. The aim was to investigate the incidence and clinical consequences of ACS after open (OR) and endovascular repair (EVAR) for ruptured and intact infrarenal abdominal aortic aneurysm (rAAA and iAAA, respectively).

METHODS

In 2008, ACS and decompression laparotomy (DL) were introduced as variables in the Swedish vascular registry (Swedvasc), offering an opportunity to study this complication in a prospective, population based design. Operations carried out in the period 2008-13 were analysed. Of 6,612 operations, 1,341 (20.3%) were for rAAA (72.0% OR) and 5,271 (79.7%) for iAAA (41.9% OR). In all, 3,171 (48.0%) were operated on by OR and 3,441 by EVAR. Prophylactic open abdomen (OA) treatment was validated through case records. Cross-matching with the national population registry secured valid mortality data.

RESULTS

After rAAA repair, ACS developed in 6.8% after OR versus 6.9% after EVAR (p = 1.0). All major complications were more common after ACS (p < .001). Prophylactic OA was performed in 10.7% of patients after OR. For ACS, DL was performed in 77.3% after OR and 84.6% after EVAR (p = .433). The 30 day mortality rate was 42.4% with ACS and 23.5% without ACS (p < .001); at 1 year it was 50.7% versus 31.8% (p < .001). After iAAA repair, ACS developed in 1.6% of patients after OR versus 0.5% after EVAR (p < .001). Among those with ACS, DL was performed in 68.6% after OR and in 25.0% after EVAR (p = .006). Thirty day mortality was 11.5% with ACS versus 1.8% without it (p < .001); at 1 year it was 27.5% versus 6.3% (p < .001). When ACS developed, renal failure, multiple organ failure, intestinal ischaemia, and prolonged intensive care were much more frequent (p < .001). Morbidity and mortality were similar, regardless of primary surgical technique (OR/EVAR/iAAA/rAAA).

CONCLUSION

ACS and OA were common after treatment for rAAA. ACS is a devastating complication after surgery for rAAA and iAAA, irrespective of operative technique, emphasizing the importance of prevention.

Decreasing incidence of ruptured abdominal aortic aneurysm already before start of screening

BACKGROUND

The aim of this study was to evaluate whether screening for abdominal aortic aneurysm (AAA) has led to a decrease in ruptured AAA (rAAA) incidence.

METHOD

The Malmö population was evaluated regarding the incidence of rAAA and elective AAA surgery 4 years before and after start of AAA-screening in 2010. Data from 1971 to 1986 (J Vasc Surg 18:74-80, 1993) and 2000-2004 (J Vasc Surg 44:237-43, 2006), enabled analysis of trends over time.

RESULTS

Analysis of time-periods 1971-1986, 2000-2004, 2006-2010 and 2010-2014 showed an incidence of rAAA of 5.6 (4.9-6.3), 10.6 (8.9-12.4), 6.1 (4.6-7.6) and 4.0 (2.9-5.1), respectively. In men aged 60-69 years the incidences were 16.0 (10.7-21.3), 45.6 (27.7-63.4), 19.3 (9.2-35.3) and 8.9 (2.8-20.6), respectively. The incidences of elective AAA surgery in men aged 60-69 years were 22.9 (16.5-29.2), 34.6 (19.1-50.2), 9.7 (1.2-18.5) and 44.2 (27.0-61.6), respectively.

CONCLUSIONS

A decrease in incidence of rAAA in men was evident before the implementation of screening. We were yet not able to demonstrate a certain reduction in rAAA incidence after the start of screening.

Comparison of long-term mortality after ruptured abdominal aortic aneurysm in England and Sweden

BACKGROUND

Concern has been raised regarding international discrepancies in perioperative mortality after repair of ruptured abdominal aortic aneurysm (rAAA). The variation in in-hospital mortality is difficult to interpret, owing to international differences in discharge strategies. This study compared 90-day and 5-year mortality in patients who had a rAAA in England and Sweden.

METHODS

Patients undergoing rAAA repair were identified from English Hospital Episode Statistics and the Swedish Vascular Registry (Swedvasc) between 2003 and 2012. Ninety-day and 5-year mortality were compared after matching for age and sex. Within-country analyses examined the impact of co-morbidity, teaching hospital status or hospital annual caseload, adjusted with causal inference techniques.

RESULTS

Some 12 467 patients underwent rAAA repair in England, of whom 83.2 per cent were men; the median (i.q.r.) age was 75 (70-80) years. A total of 2829 Swedish patients underwent rAAA repair, of whom 81.3 per cent were men; their median (i.q.r.) age was 75 (69-80) years. The 90-day mortality rate was worse in England (44.0 per cent versus 33.4 per cent in Sweden; P < 0.001), as was 5-year mortality (freedom from mortality 38.6 versus 46.3 per cent respectively; P < 0.001). In England, lower mortality was seen in teaching hospitals with larger bed capacity, higher annual caseloads and greater use of endovascular aneurysm repair (EVAR). In Sweden, lower mortality was associated with EVAR, high annual caseload, or surgery on weekdays compared with weekends.

CONCLUSION

Short- and long-term mortality after rAAA repair was higher in England. In both countries, mortality was lowest in centres performing greater numbers of AAA repairs per annum, and more EVAR procedures.

Global Experience With the Nellix Endosystem for Ruptured and Symptomatic Abdominal Aortic Aneurysms

Purpose: To assess the feasibility and safety of the endovascular aneurysm sealing (EVAS) technique in the treatment of acute abdominal aortic aneurysm (AAA). Methods: A retrospective, multicenter, observational study was conducted at 8 centers (7 European and 1 in New Zealand) experienced with EVAS in the elective setting. From February 2013 to April 2015, 58 patients (mean age 74±9 years; 46 men) with an acute AAA were treated (28 ruptured and 30 symptomatic). The primary endpoint of the study was 30-day mortality; secondary endpoints included endoleak, reinterventions, and 30-day morbidity. Results: The overall intensive care unit and hospital stays were 2.2±6.6 days and 9.7±11.4 days, respectively. Thirty-day mortality rates were 32% (9/28) for the ruptured group and 7% (2/30) for the symptomatic group, with morbidity rates of 57% and 17%, respectively. Early endoleak was present in only 2 (3%) patients, one in each group; both leaks were type Ia. Reinterventions within 30 days were performed in 8 patients in the ruptured group; in the symptomatic patients, the only perioperative reintervention was embolization a type Ia endoleak. The mean follow-up was 9.3±3.1 months in the ruptured group and 12.4±5.4 months in the symptomatic group. The mean aneurysm diameter at 30-day follow-up was 71.8±16.0 mm compared with 74.7±15.7 mm preoperatively in the ruptured group and 66.1±13.5 mm compared with 65.8±13.0 mm in the symptomatic group. Conclusion: EVAS in the acute setting appears safe and feasible and concordant with the literature for endovascular aneurysm repair. More robust prospective and comparative data are required to establish the position of the technique in the treatment algorithm of acute AAA.

Endovascular grafts for abdominal aortic aneurysm

During the last two decades, endovascular technology has revolutionized the management of patients with abdominal aortic aneurysm (AAA). Today, endovascular aortic repair (EVAR) is the treatment of choice for the majority of patients with an AAA. Randomized controlled trials provide robust evidence for the indication of AAA repair and the rationale for the use of EVAR in selected patients. However, despite that, practice varies and several areas need further elucidation. Important future challenges and areas of research include the role of medical therapy in AAA, whether the indication for repair should be any different in women and in the elderly, and long-term follow-up of patients undergoing complex EVAR with adjuncts, both for elective treatment and for ruptured AAA. Continuous rapid technical and clinical development is to be expected. In this paper, we review the current practice and evidence of stenting in AAA.

Emerging strategies to treat ruptured abdominal aortic aneurysms

Population screening programmes and a falling population prevalence of smoking have led to a declining incidence of ruptured abdominal aortic aneurysms in men. However, ruptured abdominal aortic aneurysms remain a common vascular surgical emergency, with an increasing proportion of ruptures being in women. About one quarter of the ruptures have a juxta-renal aneurysm and are more challenging to repair using endovascular technologies. Endovascular technologies may not reduce the overall mortality, compared with open surgical repair, but appear to offer early benefits with respect to patient quality of life at acceptable cost. Challenges over the next 5 years include widening the access to repair, developing an accurate bedside risk scoring tool, as well as optimising strategies for pre-operative resuscitation, standardising peri-operative care and the management of post-operative complications.

Trends in Abdominal Aortic and Iliac Aneurysm Repairs in Norway from 2001 to 2013

OBJECTIVE/BACKGROUND

The objective was to examine trends in abdominal aortic and iliac aneurysm repairs in Norway from 2001 to 2013, and study regional variations and organizational developments in this type of vascular surgery.

METHODS

This was a retrospective study on aortic and iliac aneurysm repairs using data from the Norwegian Patient Register. The vascular centers were categorized by yearly volume of repairs into small (<18), medium (18-49) and large (≥50). Incidence rates were assessed per 100,000 ≥ 60 years. The percentage of endovascular aneurysm repairs (EVAR) was calculated among the conducted repairs at the three categories of centers and the South-Eastern, Western, Central, and Northern Norway Regional Health Authority (NRHA).

RESULTS

The national incidence rates of intact repairs per 100,000 ≥ 60 years increased from 57.4 to 65.7 (p < .01). Ruptured repairs decreased from 19.7 to 9.2 (p < .01). The rate of EVAR increased from 6.0 to 29.9 (p < .01) in intact and from 0.4 to 2.5 (p < .01) in ruptured repairs. The vascular centers were reduced from 25 to 16. The rate of EVAR was 27.1% (p < .01) higher at large centers and 7.9% (p < .03) higher at medium centers compared with small centers, and from 11.1% to 15.7% higher (p < .01) at the Central, Western, and Northern NRHA compared with the South-Eastern NRHA, which had the most centers (also in the large category). The national increase in intact EVAR from 10.6% to 43.3% was less compared with many other Western countries.

CONCLUSION

During the study period the rates of intact repairs increased while the ruptured repairs decreased. EVAR was associated with centers performing high volumes of abdominal aortic and iliac aneurysm repairs and regional authorities organized with few centers.

Endovascular Versus Open Repair as Primary Strategy for Ruptured Abdominal Aortic Aneurysm: A National Population-based Study

OBJECTIVE/BACKGROUND

In randomized trials, no peri-operative survival benefit has been shown for endovascular (EVAR) repair of ruptured abdominal aortic aneurysm (rAAA) when compared with open repair. The aim of this study was to investigate the effect of primary repair strategy on early and midterm survival in a non-selected population based study.

METHODS

The Swedish Vascular Registry was consulted to identify all rAAA repairs performed in Sweden in the period 2008-12. Centers with a primary EVAR strategy (treating > 50% of rAAA with EVAR) were compared with centers with a primary open repair strategy. Peri-operative outcome, midterm survival, and incidence of rAAA repair/100,000 inhabitants aged > 50 years were assessed.

RESULTS

In total, 1,304 patients were identified. Three primary EVAR centers (pEVARc) operated on 236 patients (74.6% EVAR). Twenty-six primary open repair centers (pORc) operated 1,068 patients (15.6% EVAR). Patients treated at pEVARc were more often referrals (28.0% vs. 5.3%; p < .01), had a higher rate of respiratory comorbidity (36.5% vs. 21.9%; p < .01), and higher pre-operative systolic blood pressure (84.3 vs. 72.3 mmHg; p < .01). There was no difference in mortality based on primary treatment strategy at 30 days (pEVARc 28.0%, n = 66; pORc 27.4%, n = 296 [p = .87]), 1 year (pEVARc 39.9%, n = 93; pORc 34.7%, n = 366 [p = .19]), or 2 years (42.1%, n = 94; 38.3%, n = 394 [p = .28]), either overall or in subgroups based on age or referral status. Overall, patients treated with EVAR were older (mean age 76.4 vs. 74.0 years; p < .01), and had a lower 30 day mortality (EVAR 21.6%, n = 74; odds ratio 29.6%, n = 288 [p = < .01]). Incidence of rAAA repair was lower in pEVARc regions (6.07, 95% confidence interval [CI] 5.01-7.13) when compared with pORc regions (8.15, 95% CI 7.64-8.66).

CONCLUSION

There was no difference in mortality after rAAA repair among centers with a primary EVAR approach when compared with a primary open repair strategy, either peri-operatively or in the midterm. The study supports the early findings of the randomized controlled trials in a national population based setting.

Epidemiology of ruptured abdominal aortic aneurysms in a well-defined Norwegian population with trends in incidence, intervention rate, and mortality

OBJECTIVE

Ruptured infrarenal abdominal aortic aneurysms (rAAAs) represent both a life-threatening emergency for the affected patient and a considerable health burden globally. The aim of this study was to investigate the contemporary epidemiology of rAAA in a defined Norwegian population for which both hospital and autopsy data were available.

METHODS

This was a retrospective, single-center population-based study of rAAA. The study includes all consecutively diagnosed prehospital and in-hospital cases of rAAA in the catchment area of Stavanger University Hospital between January 2000 and December 2012. Incidence and mortality rates (crude and adjusted) were calculated using national demographic data.

RESULTS

A total of 216 patients with primary rAAA were identified. The adjusted incidence rate for the study period was 11.0 per 100,000 per year (95% confidence interval [CI], 9.6-12.5). Twenty patients died out of the hospital, and 144 of the 196 patients (73%) admitted to the hospital underwent surgery. The intervention rate varied from 48% to 81% during the study period. The adjusted mortality rate was 7.5 per 100,000 per year (95% CI, 6.3-8.8). No differences in the incidence and mortality rates were found in comparing early and late periods. The 90-day standardized mortality ratio for the study period was 37.2 (95% CI, 31.6-43.7). The overall 90-day mortality was 68% (146 of 216 persons) and 51% (74 of 144 persons) for the patients treated for rAAA.

CONCLUSIONS

We found a stable incidence and mortality rate during a decade. The prehospital death rate was lower (9%), the intervention rate (73%) higher, and the total mortality (68%) lower than in most other studies. Geographic and regional differences may influence the epidemiologic description of rAAA and hence should be taken into consideration in comparing outcomes for in-hospital mortality and intervention rates.