Abdominal Aortic Aneurysm — Threshold, Surveillance, EVAR versus Open Repair, Rupture Strategy and Screening

A 68-year-old man with a 4.6 cm aneurysm found on a scan for something else, a 71-year-old woman with a 5.2 cm aneurysm asking why her threshold differs, and a 74-year-old man with sudden back pain, hypotension and a known 7 cm aneurysm. One needs a surveillance calendar, one needs an honest uncertainty discussion, and one needs an endovascular-first rupture pathway tonight. The examiner will watch you hold small AAAs to 5.5 cm by Cochrane and CAESAR, space scans by RESCAN, choose EVAR versus open by the 15-year crossover, run rupture by IMPROVE, and screen by MASS — with every number taken from the papers named beside it.^{[1][3][10][14][18]}

Overview & Definition — the 3 cm line, the 5.5 cm line, and who they leave out

An abdominal aortic aneurysm enters surveillance at 3 cm or larger on ultrasound — the MASS detection threshold — while small AAA means 3.0 to 5.4 cm and elective repair is considered at the commonly used 5.5 cm diameter threshold.^[18][4][1] Large asymptomatic aneurysms above 5.5 cm are usually repaired and very small ones below 4.0 cm are monitored, with the 4.0 to 5.5 cm band as the contested surveillance-versus-early-repair zone.^[1] The VQI sharpens the bands by sex for outcome reporting — small below 5 cm in women and 5.5 cm in men, medium to 6.5 cm, large at 6.5 cm or more — but those are registry categories, not randomised thresholds.^[25] The strategic arc fits one sentence: randomised trials moved every decision onto diameter, growth rate and fitness — surveillance below threshold, planned repair at threshold, endovascular-first rupture strategy on the night.^[1][10][16]

Classification — four aneurysms, one diameter ruler

• Small asymptomatic (3.0–5.4 cm): ultrasound surveillance until threshold, growth or symptoms — the Cochrane/CAESAR population where early repair buys nothing.^[1][2]
• Large asymptomatic (≥5.5 cm): planned EVAR or open repair in suitable, fit patients — the EVAR-1/OVER/DREAM population.^[8][11][12]
• Ruptured: clinical diagnosis triggering the endovascular-first versus open strategy choice — the IMPROVE population, 613 randomised with 275 confirmed ruptures in the endovascular arm.^[14]
• Complex, iliac, inflammatory, mycotic and saccular disease: ESVS-named categories with their own indication logic — this topic owns infrarenal numbers only, and names the boundary rather than inventing complex-AAA figures.^[22]

Each category serves the repair decision, not a textbook chapter — diameter first, growth second, fitness third.^[7][25]

Epidemiology & Risk Factors — the denominators that frame every decision

MASS enrolled a population sample of 67,800 men aged 65 to 74, inviting 33,839 to ultrasound against 33,961 controls, with 80% uptake and 1333 aneurysms detected.^[18] The USPSTF review pooled 50 studies with 323,279 participants, including 4 population RCTs with 124,926 men for AAA death.^[20] Sweden invited 302,957 sixty-five-year-old men with 84% attendance and 1.5% AAA prevalence.^[21] RESCAN pooled 18 data sets with 15,471 patients of repeated ultrasound diameters, and the HTA programme analysed 15,475 patients from 18 surveillance studies.^[3][4] The repair trials randomise at scale: EVAR-1 1082 then 1252 patients, OVER 881 veterans across 42 centres, DREAM 351 patients, IMPROVE 613 suspected ruptures across 30 centres, with VQI reporting 22,975 elective EVARs and VSGNE 5314 infrarenal repairs.^{[8][9][11][12][14][25][24]}

Risk concentrates where the vascular surgeon already counsels: growth runs 0.35 mm per year faster in smokers and 0.51 mm per year slower with diabetes, while rupture runs almost fourfold higher in women, doubled in current smokers, and rises with blood pressure.^[4] Registry practice selects the healthiest for small repair — VQI small-AAA patients are younger with fewer comorbidities and lower predicted operative and 5-year mortality risk.^[25]

Pathophysiology — diameter-driven growth, linear by default, early growth as oracle

The diameter law is the mechanism anchor: each 0.5 cm adds about 0.59 mm per year of growth and multiplies rupture by 1.91, so the aneurysm accelerates as it enlarges.^[3] Growth averages 2.3 mm per year across the literature with small-AAA rupture between 0 and 1.6 per 100 person-years, and growth steps up markedly with diameter.^[4] The CT-measured pattern is linear by default — median 0.17 cm per year, 70% linear, with staccato growth at 3% and exponential at 4% — and baseline diameter explains only 5.4% of growth-rate variance, so the ruler needs a calendar, not just a number.^[6] The oracle is early relative growth: baseline diameter carries a 9.16 hazard for future intervention or rupture and a first-24-month growth of 5% or more carries 4.46, while slow-growing small aneurysms sit at 0.98 event-free at 5 years.^[7] Large aneurysms at 50 mm or more grow more rapidly, and a 30 mm aorta carries 4.0% or less rupture risk over 5 years — the natural-history numbers behind every surveillance interval.^[5]

Clinical Presentation — screen-detected, symptomatic and ruptured

The screen-detected candidate declares through the programme: a 65-to-74-year-old man with a 3 cm or larger aorta on invitation ultrasound, entering repeat scans for a mean 4.1 years with surgery at 5.5 cm, 1 cm per year expansion, or symptoms.^[18] The surveillance candidate declares through stability: small, asymptomatic, growing linearly under threshold — the 70% whose calendar, not whose symptoms, drives the next scan.^[6][3] The rupture candidate declares through emergency: a clinical diagnosis of ruptured aneurysm headed for an endovascular-first or open strategy, with only 174 of 275 confirmed IMPROVE ruptures anatomically suitable for EVAR — suitability, not preference, gates the strategy.^[14] The emergency arithmetic sets the stakes: 6% 30-day death after elective surgery against 37% after emergency surgery in MASS, with ruptured AAA mortality estimated at 81% in the USPSTF review.^[18][20]

Differential Diagnosis — surveillance versus repair versus rupture pathway

Split stable small AAA (survey by the interval ladder) from threshold AAA at 5.5 cm or with 1 cm per year growth or symptoms (plan repair) from suspected rupture (activate the rupture pathway tonight).^[1][2][14] Split EVAR-suitable (the 174 of 275 IMPROVE ruptures, the anatomically suitable and fit EVAR-1 electives) from EVAR-unsuitable or unfit — open repair or, in the unfit elective, honest acknowledgement that EVAR over no intervention moves aneurysm-related but not all-cause death.^[14][8][13] Split fast early growers (5% or more in 24 months, HR 4.46) from slow small growers (0.98 event-free at 5 years) — same diameter, different calendars.^[7] Split screening benefit (AAA death, rupture, emergency operations all down) from screening harm (44% more procedures, no all-cause signal) when counselling the invited man.^[20]

Name the category aloud before ordering the scan — the viva rewards the candidate who separates what diameter decides from what only growth, anatomy or fitness decides.^[7][14][25]

Clinical & Bedside Assessment — diameter, growth trajectory and fitness

Use the interval ladder honestly: several-year intervals suit 3.0 to 4.0 cm, around 1 year suits 4.0 to 4.9 cm, and 6 months suits 5.0 to 5.4 cm — longer than current UK programme intervals, and cost-effective for the smallest aneurysms.^[4] Or quote RESCAN directly: a 7.4-year interval holds exceedance below 10% at 3.0 cm while 5.0 cm needs 8 months, and rupture below 1% needs 8.5 years versus 17 months.^[3] Read the early-growth oracle at 24 months: below 5% growth in a small AAA means very low medium-term rupture-or-repair risk and can triage surveillance intensity.^[7] Judge fitness the way the trials did: EVAR-1 randomised the anatomically suitable and fit for open repair, OVER randomised veterans fit for both, and registry small repairs select the young and healthy — so fitness is an entry criterion, not an afterthought.^[8][11][25] State the sub-aneurysmal caution: a 2.5 to 2.9 cm baseline aorta is not a discharge — about half of MASS normal-screen ruptures started there.^[19]

Investigations — ultrasound for surveillance, CT for anatomy and growth

Screen with one-time ultrasound at 65 in men — the MASS/Swedish instrument with 80 to 84% uptake — and survey small AAA with serial ultrasound, escalating to CT-measured maximum transverse diameter where growth decisions turn.^[18][21][4] The N-TA3CT protocol shows the CT standard: maximum transverse diameter every 6 months, with under 4.25 cm never breaching sex-specific thresholds at 2 years.^[6] Assess EVAR suitability explicitly, because anatomy gates strategy: only 174 of 275 confirmed IMPROVE ruptures qualified, and CAESAR lost 16.4% of surveillance patients to EVAR feasibility by 36 months — growing out of EVAR candidacy is a real surveillance failure mode.^[14][2] State the honesty the examiner probes: no keeper abstract supplies neck-length, neck-angle or iliac-landing numbers, so assess suitability by named trial criteria and vascular-surgical judgement rather than invented anatomy cutoffs.

Management — Small AAA: survey, do not repair early

Give Cochrane exactly: 4 trials with 3314 participants of 4.0 to 5.5 cm aneurysms — every trial favoured surveillance early through operative mortality, none favoured early repair late, with pooled open-repair survival at HR 0.99 and EVAR at RR 1.92 (nonsignificant), and no subgroup by diameter, age or sex to rescue repair.^[1] Give CAESAR exactly: 360 patients of 4.1 to 5.4 cm, immediate EVAR versus surveillance to 5.5 cm, 1 cm per year or symptoms — mortality HR 0.76 nonsignificant at 14.5 versus 10.1%, with two late ruptures both under surveillance, yet 59.7% of surveillance aneurysms needing delayed repair by 36 months and 84.5% by 54 months.^[2] The resolution is the viva sentence: surveillance is safe with close supervision, repair waits for threshold — but warn that 3 in 5 surveillance aneurysms need repair by 3 years and 1 in 6 loses EVAR feasibility.^[2][1] Set the cost honesty beside it: open repair cost GBP 1064 more per participant over 18 months, and EVAR cost USD 27,951 more at 6 months with convergence by 4 years — early repair spends without surviving better.^[1]

Management — Elective repair at threshold: EVAR early, open late

Give EVAR-1 2005 exactly: 1082 patients of 5.5 cm or more across 34 proficient hospitals — 4-year death about 28% in both arms, aneurysm-related 4 versus 7% favouring EVAR, complications 41 versus 9% against EVAR, costs GBP 13,257 versus 9946.^[8] Give the NEJM follow-up exactly: 1252 patients, 30-day death 1.8 versus 4.3% (OR 0.39) — then convergence to HR 1.03 overall and 0.92 aneurysm-related, with fatal endograft ruptures and new complications to 8 years at higher cost.^[9] Give the 15-year tail exactly, because this is the crossover the viva rewards: EVAR mortality lower at 0 to 6 months (HR 0.61 total, 0.47 aneurysm-related) but open repair lower beyond 8 years (HR 1.25 total, 5.82 aneurysm-related), driven by 13 secondary sac ruptures after EVAR against 2 after open — hence lifelong EVAR surveillance with reintervention.^[10] Give OVER exactly: 881 veterans, perioperative death 0.5 versus 3.0%, 2-year death 7.0 versus 9.8% nonsignificant, with EVAR halving blood loss (200 versus 1000 mL), stay (3 versus 7 days) and ICU (1 versus 4 days) at a fluoroscopy price.^[11] Give DREAM exactly: 351 patients, 6-year survival 69.9 versus 68.9% tied, but freedom from reintervention 81.9 versus 70.4% favouring open.^[12] Give Cochrane EVAR exactly: 2790 pooled, short-term 1.4 versus 4.2% (OR 0.33), intermediate and long-term tied, reinterventions doubled (OR 1.98) — and in the unfit, EVAR over nothing moves aneurysm-related death (HR 0.53) without moving all-cause death (HR 0.99), so preference and anatomy carry the unfit decision.^[13]

The surgical resolution: offer EVAR for perioperative safety, fast recovery and high operative risk; offer open repair for young fit patients with long horizons who accept laparotomy for durability — and book lifelong imaging after EVAR, because the sac can still kill at 8 years.^[10][12][13]

Management — Rupture: endovascular-first when suitable

Give IMPROVE 30-day exactly, because this is the surgeon's night trial: 613 suspected ruptures across 30 centres, endovascular-first (open if unsuitable) versus open — 30-day death 35.4 versus 37.4% (OR 0.92, nonsignificant), with women possibly gaining more (OR 0.44 versus 1.18, interaction P 0.02) and far more endovascular patients discharged straight home (94 versus 77%).^[14] Give 1-year exactly: death 41.1 versus 45.1% still tied, but stays of 17 versus 26 days, better EQ-5D, and an incremental net benefit of GBP 3877 — no survival gain, but faster discharge with better quality of life and cost-effectiveness.^[15] Give 3-year exactly: the mid-term divergence — HR 0.57 from 3 months to 3 years, 3-year death 48 versus 56% (42 versus 54% in repaired ruptures), reinterventions tied (HR 1.02), QALYs up 0.17, costs down GBP 2605, over 90% probably cost-effective — converging again toward 60% each by 7 years.^[16] Give the reintervention paper exactly: 186 versus 226 per 100 person-years early, slowing to 9.5 versus 6.0 mid-term with a third life-threatening, 13% needing at least one mid-term reintervention — endoleak dominating post-EVAR, distal aneurysms post-open — with amputation fivefold less common after EVAR and bespoke post-rupture surveillance mandated.^[17]

The bedside resolution: run the endovascular-first strategy for suspected rupture where morphology suits and the service exists around the clock; open repair where it does not — and consent for reintervention as the norm, not the exception.^[16][17][14]

Management — Screening: invite at 65, counsel the trade

Give MASS exactly: 67,800 men invited or not at 65 to 74 — 42% fewer AAA deaths (65 versus 113), 53% in attenders, with elective repair at 6% death against emergency at 37%.^[18] Give the 13-year tail exactly: 42% AAA-death reduction sustained (224 versus 381), all-cause down 3%, 216 invited to save one death — benefit accumulating, not fading.^[19] Give USPSTF exactly: invitation tied to AAA death OR 0.65, rupture OR 0.62 and emergency operations OR 0.57 — but all-cause RR 0.99 with 44% more procedures and no long-term quality-of-life difference.^[20] Give Sweden exactly: the contemporary proof — 302,957 invited, 84% attend, 1.5% prevalence, 30-day death 0.9% overall (1.3 open, 0.3 EVAR), 667 screened and 1.5 operated per premature death prevented, EUR 7770 per QALY.^[21] Counsel the invited man with both sides: screening halves his AAA-death risk and emergency operation risk, at the price of more elective procedures and no proven longer life overall.^[20][18]

Complications & Pitfalls — the six traps

The small-repair trap — 40% of VSGNE repairs and 41% of VQI EVARs sit below the randomised threshold, three-quarters endovascular — trial evidence supports none of it, and the patients are selected young and fit, flattering the numbers.^[24][25][1]

The EVAR-and-forget trap — complications to 8 years, secondary sac rupture killing 7% of EVAR patients late, reinterventions doubled — lifelong surveillance with reintervention is the price of the perioperative win.^[9][10][13]

The open-by-default rupture trap — open-first for every rupture ignores the 3-year 48-versus-56% split, the 17-versus-26-day stays and the home-discharge gap; suitability and service, not habit, should gate the strategy.^[16][15][14]

The female-threshold trap — rupture fourfold higher in women with faster growth and worse repair outcomes, against male-built trials with no verified female number — individualise, escalate early, never quote 5.5 cm as her evidence.^[4][26][20]

The normal-screen discharge trap — a 2.5 to 2.9 cm baseline aorta still ruptures; half of MASS normal-screen ruptures started there.^[19]

The all-cause counselling trap — promising longer life from screening overreaches: AAA death falls 42% in MASS (OR 0.65 in the USPSTF pool) while all-cause mortality sits at RR 0.99 — promise fewer aneurysm deaths and fewer emergency operations, not more years.^[20][19]

Prognosis & Disposition — the numbers that set expectations

^{[1] [11] [10] [16] [19] [25]}

Every threshold-crossing or ruptured AAA needs vascular-surgical ownership with anaesthetic, critical-care and interventional cover, a named surveillance owner after EVAR, and a screening-programme link for the family — set-and-forget after repair is a failure-to-rescue setup. Modifiers: diameter and early growth (repair urgency), anatomy and fitness (EVAR versus open), sex (threshold uncertainty), and presentation acuity (elective 6% versus emergency 37%).^{[7][14][26][18]}

Special Populations — surgical contexts that change the emphasis

• Women: faster growth, smaller-diameter rupture, worse ruptured and intact repair outcomes — against male-built trials; no verified threshold, so individualise early with vascular surgery.^[26][4][20]
• Large AAA (≥6.5 cm): the worst EVAR band — 1.6% 30-day death, most cardiac, respiratory and renal complications, 82% 1-year reintervention-free and 75% 5-year survival — plan meticulously, consent heavily.^[25]
• Unfit for open repair: EVAR over nothing halves aneurysm-related death without moving all-cause death — decide by anatomy and preference, never by default.^[13]
• Sub-aneurysmal aorta (2.5–2.9 cm): not normal — half of normal-screen ruptures start here; keep in the programme.^[19]
• Symptomatic intact AAA: an ESVS-named rupture-pathway category alongside rupture itself — treat as urgent vascular-surgical business, and name the evidence boundary for exact timing numbers, which no keeper abstract supplies.^[22]
• Complex, iliac, inflammatory, mycotic and saccular disease: ESVS-managed with dedicated indication logic — refer to the guideline and the vascular surgeon, and never stretch infrarenal trial numbers across them.^[22]

Evidence, Guidelines & Regional Differences — the five stories and who led them

• The threshold story (UK-led): small-AAA randomisation → Cochrane pool of 3314 with no long-term difference → CAESAR confirming for EVAR with the feasibility-loss warning → RESCAN/HTA turning growth into calendars.^[1][2][3][4]
• The durability story (UK/Europe/US): EVAR-1 perioperative win → NEJM convergence → 15-year open catch-up via sac rupture → OVER recovery numbers → DREAM reintervention split → Cochrane synthesis with the unfit EVAR-2 boundary.^{[8][9][10][11][12][13]}
• The rupture story (UK-led): IMPROVE 30-day tie with the female signal → 1-year faster-discharge win → 3-year survival and cost win → reintervention audit mandating bespoke surveillance.^{[14][15][16][17]}
• The screening story (UK/US/Sweden): MASS 42% → 13-year sustainment → USPSTF all-cause null with procedure excess → Swedish contemporary cost-effectiveness.^{[18][19][20][21]}
• The guideline split (Europe/UK/US): ESVS 160 recommendations → NICE open-first versus ESVS EVAR-first discordance explained by methods → SVS 5.5 cm threshold versus 40% sub-threshold real-world repair.^[22][23][24]
• Sibling-topic boundary: shock owns pressors and perfusion targets; massive transfusion owns blood strategy — this topic owns diameter, growth, repair choice, rupture strategy and screening. Cite each where it lives.
• Guideline honesty: ESVS fields 160 recommendations from service standards to complex and iliac disease with shared decision-making; NICE answers 46 questions with RCT-plus-modelling discipline — both direct individualisation, and neither supplies the open-technique or drug numbers this topic declines to invent.^[22][23]

Exam Pearls — the one-liners that score

• Cochrane small in one breath: 4 trials, 3314 patients 4.0–5.5 cm — pooled open HR 0.99, EVAR RR 1.92 ns; no early-repair advantage by age, diameter or sex.^[1]
• CAESAR in one breath: 360 patients, HR 0.76 ns, 14.5 vs 10.1% — 59.7% need repair by 36 months, 16.4% lose EVAR feasibility.^[2]
• RESCAN in one breath: 15,471 patients — per 0.5 cm, +0.59 mm/yr growth and ×1.91 rupture; 7.4 yr at 3.0 cm, 8 mo at 5.0 cm; rupture-safe 8.5 yr vs 17 mo.^[3]
• Growth modifiers in one breath: smokers +0.35, diabetes −0.51; rupture ×4 women, ×2 smokers, up with BP; 30 mm ≤4%/5 yr.^[4][5]
• Early growth in one breath: diameter HR 9.16, ≥5% early growth HR 4.46; slow small growth 0.98 event-free at 5 yr; 70% linear, median 0.17 cm/yr.^[7][6]
• EVAR-1 in one breath: 4-yr death ~28% both, aneurysm death 4 vs 7%, complications 41 vs 9%, £13,257 vs £9946 — then 30-day 1.8 vs 4.3%, then 15-yr open wins beyond 8 yr (sac rupture 13 vs 2).^[8][9][10]
• OVER in one breath: 881 veterans — periop 0.5 vs 3.0%, 2-yr tied; blood 200 vs 1000 mL, stay 3 vs 7 d, ICU 1 vs 4 d.^[11]
• DREAM/Cochrane in one breath: 6-yr survival 69.9 vs 68.9% tied, reintervention freedom 81.9 vs 70.4%; pooled short-term 1.4 vs 4.2%, long-term tied, reinterventions doubled.^[12][13]
• IMPROVE in one breath: 613 suspected ruptures — 30-day 35.4 vs 37.4% ns (women OR 0.44), home 94 vs 77%; 1-yr tied with 17 vs 26 d stays; 3-yr 48 vs 56% (repaired 42 vs 54%); reinterventions 186 vs 226 early, endoleak rules late.^{[14][15][16][17]}
• MASS in one breath: 67,800 men — 42% AAA-death cut, elective 6% vs emergency 37%; 13-yr sustained, NNI 216; USPSTF all-cause RR 0.99 with 44% more ops; Sweden NNS 667 at €7770/QALY.^{[18][19][20][21]}
• Guidelines in one breath: ESVS 160 recommendations; NICE open-first elective vs ESVS EVAR-first; NICE EVAR for ruptures in women, open for ruptured men under 71; SVS 5.5 cm vs 40% sub-threshold practice.^[22][23][24]
• Women in one breath: faster growth, smaller rupture, worse repair outcomes — male-built trials, no verified threshold.^[26]

Revision summary

Survey small AAA (Cochrane 3314-patient tie; CAESAR 59.7% delayed repair with 16.4% feasibility loss) on a RESCAN/HTA calendar (years at 3–4 cm, ~1 year at 4–4.9, 6 months at 5–5.4), weighting early growth (HR 4.46) and modifiers (smoking, sex, BP).^{[1][2][3][4][7]} Repair at threshold by fitness and anatomy: EVAR for perioperative safety (30-day 1.8 vs 4.3%, OVER 0.5 vs 3.0%) with lifelong surveillance for the late sac-rupture tail (15-yr open advantage beyond 8 yr), open for durability (DREAM reintervention freedom 81.9 vs 70.4%).^{[9][10][11][12]} Run rupture endovascular-first when suitable (IMPROVE 30-day tie, 3-year 48 vs 56%, QALY and cost wins) with bespoke reintervention watch (endoleak dominant, amputation rarer).^[14][16][17] Screen once at 65 in men (MASS 42% sustained, NNI 216; Sweden NNS 667) while counselling the all-cause null and procedure excess (USPSTF RR 0.99, OR 1.44).^[19][21][20] Hold guidelines honestly (NICE open-first vs ESVS EVAR-first; SVS 5.5 cm vs 40% sub-threshold repair) and the female threshold gap.^[23][24][26]

References26ShowHide

1. [1]Ulug P, et al. Surgery for small asymptomatic abdominal aortic aneurysms. Cochrane Database Syst Rev, 2020.PMID 32609382
2. [2]Cao P, et al. Comparison of surveillance versus aortic endografting for small aneurysm repair (CAESAR): results from a randomised trial. Eur J Vasc Endovasc Surg, 2011.PMID 20869890
3. [3]Bown MJ, et al. Surveillance intervals for small abdominal aortic aneurysms: a meta-analysis. JAMA, 2013.PMID 23443444
4. [4]Thompson SG, et al. Systematic review and meta-analysis of the growth and rupture rates of small abdominal aortic aneurysms: implications for surveillance intervals and their cost-effectiveness. Health Technol Assess, 2013.PMID 24067626
5. [5]Vardulaki KA, et al. Growth rates and risk of rupture of abdominal aortic aneurysms. Br J Surg, 1998.PMID 9876073
6. [6]Olson SL, et al. Evaluating Growth Patterns of Abdominal Aortic Aneurysm Diameter With Serial Computed Tomography Surveillance. JAMA Surg, 2021.PMID 33595625
7. [7]Kindon AJ, et al. Early Relative Growth Rate of Abdominal Aortic Aneurysms and Future Risk of Rupture or Repair. Eur J Vasc Endovasc Surg, 2023.PMID 37567340
8. [8]EVAR trial participants Endovascular aneurysm repair versus open repair in patients with abdominal aortic aneurysm (EVAR trial 1): randomised controlled trial. Lancet, 2005.PMID 15978925
9. [9]Greenhalgh RM, et al. Endovascular versus open repair of abdominal aortic aneurysm. N Engl J Med, 2010.PMID 20382983
10. [10]Patel R, et al. Endovascular versus open repair of abdominal aortic aneurysm in 15-years' follow-up of the UK endovascular aneurysm repair trial 1 (EVAR trial 1): a randomised controlled trial. Lancet, 2016.PMID 27743617
11. [11]Lederle FA, et al. Outcomes following endovascular vs open repair of abdominal aortic aneurysm: a randomized trial. JAMA, 2009.PMID 19826022
12. [12]De Bruin JL, et al. Long-term outcome of open or endovascular repair of abdominal aortic aneurysm. N Engl J Med, 2010.PMID 20484396
13. [13]Paravastu SC, et al. Endovascular repair of abdominal aortic aneurysm. Cochrane Database Syst Rev, 2014.PMID 24453068
14. [14]Powell JT, et al. Endovascular or open repair strategy for ruptured abdominal aortic aneurysm: 30 day outcomes from IMPROVE randomised trial. BMJ, 2014.PMID 24418950
15. [15]IMPROVE Trial Investigators Endovascular strategy or open repair for ruptured abdominal aortic aneurysm: one-year outcomes from the IMPROVE randomized trial. Eur Heart J, 2015.PMID 25855369
16. [16]IMPROVE Trial Investigators Comparative clinical effectiveness and cost effectiveness of endovascular strategy v open repair for ruptured abdominal aortic aneurysm: three year results of the IMPROVE randomised trial. BMJ, 2017.PMID 29138135
17. [17]Powell JT, et al. Editor's Choice - Re-interventions After Repair of Ruptured Abdominal Aortic Aneurysm: A Report From the IMPROVE Randomised Trial. Eur J Vasc Endovasc Surg, 2018.PMID 29503083
18. [18]Ashton HA, et al. The Multicentre Aneurysm Screening Study (MASS) into the effect of abdominal aortic aneurysm screening on mortality in men: a randomised controlled trial. Lancet, 2002.PMID 12443589
19. [19]Thompson SG, et al. Final follow-up of the Multicentre Aneurysm Screening Study (MASS) randomized trial of abdominal aortic aneurysm screening. Br J Surg, 2012.PMID 23034729
20. [20]Guirguis-Blake JM, et al. Primary Care Screening for Abdominal Aortic Aneurysm: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force. JAMA, 2019.PMID 31821436
21. [21]Wanhainen A, et al. Outcome of the Swedish Nationwide Abdominal Aortic Aneurysm Screening Program. Circulation, 2016.PMID 27630132
22. [22]Wanhainen A, et al. Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms. Eur J Vasc Endovasc Surg, 2024.PMID 38307694
23. [23]Powell JT, et al. Analysis of the Differences Between the ESVS 2019 and NICE 2020 Guidelines for Abdominal Aortic Aneurysm. Eur J Vasc Endovasc Surg, 2020.PMID 32439141
24. [24]Schlieder I, et al. Increasing disparity between Society for Vascular Surgery guidelines for infrarenal abdominal aortic aneurysm repair and real-world practice. J Vasc Surg, 2021.PMID 32889077
25. [25]Jones DW, et al. Differences in patient selection and outcomes based on abdominal aortic aneurysm diameter thresholds in the Vascular Quality Initiative. J Vasc Surg, 2019.PMID 31147111
26. [26]Deery SE, et al. Should Abdominal Aortic Aneurysms in Women be Repaired at a Lower Diameter Threshold? Vasc Endovascular Surg, 2018.PMID 29720046