Synopsis
Interpret surveillance after endovascular aortic repair, distinguish endoleak mechanisms, and escalate sac growth or device failure safely.
- Lifelong imaging surveillance is required after EVAR or TEVAR because endoleak, migration, component failure, kinking and sac enlargement can arise late.
- Type I is an inadequate proximal or distal seal; type III is component separation or fabric failure, and both directly pressurize the sac.
- Type II is retrograde branch-vessel filling; intervene for associated aneurysm sac expansion rather than for the label alone.
Key red flags
New pain, syncope, hypotension or anaemia after endovascular repair requires emergency rupture assessment even if the previous surveillance scan was reassuring.
A new type I or type III endoleak transmits systemic pressure to the sac and needs prompt specialist re-intervention planning.
Aneurysm sac enlargement is treatment-relevant even when no leak is visible because occult type I or III leak, endotension and infection must be excluded.
Fever, bacteraemia, perigraft gas or increasing periaortic inflammation after the early postoperative period suggests graft infection rather than a sterile endoleak.
Type I attachment failure or type III graft disruption creates arterial-pressure sac filling and a continuing rupture mechanism.
Progressive sac growth without visible flow suggests occult endoleak, endotension, measurement inconsistency or graft infection.
New buttock or leg claudication, rest pain, reduced pulses or acute ischaemia can follow graft limb stenosis, kinking or occlusion.
Fever, malaise, bacteraemia, back pain, perigraft gas or soft-tissue change requires urgent assessment for endograft infection.
Investigation priorities
Track sac diameter and detect EVAR-related device complications over life.
Management branches
A surveillance scan reports increasing sac diameter after a previously stable infrarenal EVAR.
- Retrieve the implant record, early postoperative CTA, smallest sac measurement, intervening images, renal function and current symptoms before classifying risk.
- Re-measure the sac using the same plane and method, then inspect proximal and distal seals, overlap, migration, limbs and arterial or delayed sac enhancement.