01Purpose and principlesWhat the treatment does and how it fits into care.
Open surgical repair excludes an aneurysm by clamping the aorta and suturing a prosthetic graft in place through an abdominal or retroperitoneal approach. Standard EVAR introduces a stent graft through the iliac and femoral arteries, seals above and below the aneurysm, and redirects blood through the graft. EVAR generally has lower early mortality and a shorter initial recovery, but requires anatomical suitability, surveillance and potential secondary procedures for endoleak, migration, limb failure or sac expansion. Open repair imposes greater early cardiac, pulmonary and renal stress and a longer recovery, but has established durability.
The decision begins with whether repair is appropriate at all. NICE says to consider repair for a symptomatic unruptured AAA, an asymptomatic AAA larger than 4.0 cm that has grown by more than 1 cm in one year, or an asymptomatic AAA at least 5.5 cm, using maximum AP inner-to-inner ultrasound diameter. Size is not an automatic command: discuss morphology, age, life expectancy, fitness, comorbidity, rupture risk, peri-operative risk, hospital stay, recovery, reintervention and surveillance. Conservative management may best serve someone whose competing mortality or operative burden outweighs rupture prevention.
For UK practice, NICE recommends offering open repair for qualifying unruptured AAA unless abdominal copathology, anaesthetic risk or medical comorbidity contraindicates it. Consider standard EVAR for hostile abdomen, horseshoe kidney, stoma or other person-specific considerations that favour it; if open repair is contraindicated by anaesthetic risk or comorbidity, consider EVAR or conservative management. ESVS 2024 has different European recommendations: EVAR should be considered preferred for most people with suitable anatomy and reasonable life expectancy, while open repair should be considered preferred for most with long life expectancy. These frameworks must be labelled by jurisdiction rather than blended into one rule.
Key points
- First confirm that symptoms, size or growth justify considering aneurysm repair.
- NICE offers open repair for qualifying unruptured AAA unless specific contraindications apply.
- NICE considers EVAR when abdominal copathology or individual factors make it preferable.
- If anaesthetic risk or comorbidity contraindicates open repair, consider EVAR or conservative management.
- EVAR requires suitable sealing zones and access anatomy plus lifelong imaging surveillance.
- Open repair carries greater early physiological stress but avoids endograft-specific late failures.
- Shared decisions include life expectancy, fitness, morphology, recovery, reintervention and surveillance burden.
- ESVS European advice differs: EVAR is preferred for most suitable patients, while long life expectancy favours open repair.
02Indications, selection and cautionsWho may benefit, who needs urgent treatment and important alternatives.
Symptoms, qualifying rapid growth or an asymptomatic inner-to-inner AP ultrasound diameter at least 5.5 cm prompt repair consideration.
Standard EVAR needs adequate proximal and distal sealing zones, workable neck morphology and safe iliac-femoral access.
Cardiac, pulmonary, renal and frailty assessment estimates tolerance of open repair and meaningful recovery.
Life expectancy determines whether immediate EVAR benefit or longer-established open durability matters most.
New pain or tenderness requires urgent vascular reassessment rather than continuing an elective modality discussion.
03Assessment before treatmentTests and checks that guide safe selection.
Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.
- 01
Thin-slice arterial CT angiographyFirst step - Why
- Map aneurysm morphology, branch vessels and access anatomy
- Interpretation and limitations
- CTA determines standard EVAR feasibility, clamp level and graft planning; centreline measurements should follow device-specific requirements.
- 02
Aortic ultrasound review - Why
- Confirm the NICE diameter or growth indication for repair
- Interpretation and limitations
- Use maximum AP inner-to-inner values and verify serial method before calling growth greater than 1 cm yearly.
- 03
Cardiopulmonary exercise testing - Why
- Support elective physiological assessment and shared decision-making
- Interpretation and limitations
- NICE says to consider it when results will assist discussion; it is not a single pass-fail gate for repair.
- 04
Renal function and blood tests - Why
- Identify anaemia, kidney impairment and correctable peri-operative risk
- Interpretation and limitations
- Renal dysfunction affects contrast strategy and both procedures; abnormalities prompt optimisation rather than an automatic technique choice.
- 05
Cardiorespiratory assessment - Why
- Estimate open-repair stress and anaesthetic risk realistically
- Interpretation and limitations
- Integrate history, examination and indicated testing; do not use one risk score alone to deny unruptured repair.
04Treatment approachPreparation, options, escalation and aftercare.
01Decision pathwayConfirm repair and choose strategyFirst stepAn unruptured AAA meets NICE criteria for considering repair+
- 1Verify symptoms, maximum AP inner-to-inner ultrasound size and any documented growth.
- 2Obtain CTA to define neck, branch-vessel and iliac access anatomy.
- 3Assess fitness, life expectancy, abdominal copathology and capacity for surveillance.
- 4Explain open, standard EVAR and conservative options with early and late trade-offs.
- 5Apply NICE in UK practice and document the jointly chosen plan.
02NICE routeOpen repair suitableA qualifying unruptured AAA has no contraindication to open surgery+
- 1Offer open surgical repair under the NICE UK recommendation.
- 2Discuss higher early physiological burden, hospital stay and recovery expectations.
- 3Explain durable exclusion and the possibility of late graft or anastomotic complications.
- 4Optimise cardiovascular, respiratory, renal and nutritional risks before surgery.
03NICE alternativeEVAR or conservative managementAlternativeAbdominal factors favour EVAR or open surgery is contraindicated+
- 1Confirm that anatomy fits an approved standard endograft instruction for use.
- 2If abdominal copathology favours EVAR, consider it with the person's priorities.
- 3If comorbidity contraindicates open repair, compare EVAR directly with conservative management.
- 4Confirm willingness and ability to attend long-term surveillance before proceeding.
04Post-procedure pathwayTechnique-specific follow-upRepair is complete and the patient enters long-term follow-up+
- 1After EVAR enrol the patient in risk-based surveillance imaging for graft complications.
- 2Investigate suspected endoleak with contrast-enhanced CTA or contrast ultrasound when CTA is contraindicated.
- 3After open repair review recovery and later graft, anastomotic or new aneurysm complications when clinically indicated.
05Complications, monitoring and follow-upAdverse effects, response and longer-term review.
- Before repair, track symptom status, ultrasound diameter, growth, fitness and shared-decision outcomes.
- After EVAR, enrol every patient in imaging surveillance tailored to complication risk.
- Monitor renal, cardiac, pulmonary, bowel and limb complications after either procedure.
- After open repair, monitor wound recovery, incisional hernia and late graft or anastomotic problems.
- Reassess conservative management if symptoms, growth, fitness or patient preference changes.
06Special situationsVariants, exceptions and circumstances that change the usual approach.
Early versus late trade-off
Randomised evidence shows an early survival advantage with EVAR that diminishes over time, while late endograft complications and reinterventions make longevity central to choice.
NICE jurisdiction
In UK practice NICE offers open repair when suitable, then considers EVAR for specific abdominal factors or alongside conservative management when open repair is contraindicated.
ESVS jurisdiction
European ESVS 2024 guidance prefers EVAR for most patients with suitable anatomy and reasonable life expectancy, but prefers open repair for most patients with long life expectancy.
Instructions for use
ESVS advises against elective EVAR outside the manufacturer's device instructions because hostile neck or access anatomy increases seal failure, migration and reintervention risk.
Complex EVAR boundary
NICE places special consent, audit and research conditions on complex EVAR because long-term benefit over open repair or conservative management remains uncertain.
Conservative is active
Choosing no operation still requires cardiovascular prevention, symptom safety-netting and a clear surveillance or reassessment plan where future repair remains plausible.
07Common pitfallsFrequent interpretation and management errors.
- 01
Equating anatomical EVAR feasibility with clinical benefit ignores life expectancy and surveillance burden.
- 02
Presenting EVAR as a one-off cure omits lifelong imaging and possible reintervention.
- 03
Treating open repair as automatically unsuitable in old age substitutes age for individual physiological assessment.
- 04
Combining NICE and ESVS modality recommendations without labels creates a false universal rule.
- 05
Using CT diameter directly against an inner-to-inner ultrasound threshold can misclassify eligibility.
- 06
Offering repair whenever 5.5 cm is reached ignores competing mortality, frailty and informed preference.