Aortic Stent Surveillance and Endoleaks

Aortic stent surveillance means planned follow-up after endovascular repair. Imaging checks whether the graft continues to work as intended and whether the treated aneurysm or remaining aorta is changing. A successful operation is the start of this long-term plan. Problems can develop without symptoms, so feeling well does not replace a scheduled scan.

What does follow-up look for?

After abdominal EVAR, the team checks the aneurysm sac, seal, graft position and blood flow through the device. After TEVAR, imaging also assesses the treated chest aorta and relevant untreated segments. Following dissection, the size of the aorta and flow within the true and false channels can change over time.

After fenestrated or branched repair, follow-up includes the connections to arteries supplying the kidneys and abdominal organs. A graft can develop narrowing, blockage, separation, movement or a leak. Surveillance also looks for progression of the underlying aortic disease.

What is an endoleak?

An endoleak means blood is still reaching the aneurysm sac outside the stent graft after endovascular aneurysm repair. It is an imaging finding with several possible mechanisms. It does not necessarily mean that the aneurysm has ruptured, but some types keep the sac under significant pressure and require prompt treatment.

Type I and type III endoleaks

A type I endoleak involves an inadequate seal at an end of the graft. A type III leak involves a problem with the graft material or a connection between components. These leaks can expose the aneurysm to arterial pressure and usually need prompt specialist assessment and correction. The response depends on the anatomy and clinical situation.

Type II endoleaks

A type II endoleak comes from blood flowing back through smaller branches into the aneurysm sac. Some settle or remain stable and can be monitored. Persistent leakage with sac enlargement is more concerning. Before treatment, the team needs to confirm the cause and exclude a different leak. Finding a type II endoleak does not automatically mean another operation is required.

What if the sac grows without a visible leak?

This needs further evaluation rather than reassurance from one negative scan. A small or intermittent leak may be difficult to detect. Sac expansion without an identified leak is sometimes called endotension or type V endoleak, but other causes must be considered. The investigation and treatment plan are individual.

Which scans will I need?

CT angiography provides detailed information about the graft, seal and surrounding aorta. Ultrasound can assess many abdominal repairs without ionising radiation and may be used for suitable follow-up. Contrast-enhanced ultrasound or MRI can help answer selected questions. No single test is ideal for every repair or every suspected complication.

Kidney function, contrast history, the type of graft and the clinical question affect the choice. MRI compatibility must be checked against implant information. Bring the implant card and previous scan records where available, especially when moving between care teams.

There is usually an early postoperative assessment followed by scheduled long-term imaging. Frequency depends on the procedure, initial scan, aneurysm behaviour, device requirements and any abnormalities. Some patients need closer checks; others can have longer intervals after stable results. Ask for your next date and who will review it, rather than adopting someone else's schedule.

When might another procedure be needed?

Further treatment may be recommended for an important leak, loss of seal, increasing aneurysm size, graft or branch blockage, or other evidence of device failure. Options include an additional graft component, relining, treatment to close selected leaking vessels, or open surgery. The choice depends on the problem and your health.

Another procedure has its own risks, including bleeding, kidney injury, infection and unintended loss of blood flow. Some problems recur despite treatment. The decision should compare the risk of observation with the likely benefit and burden of intervention; repeat imaging remains necessary afterwards.

Which symptoms should not wait for a routine scan?

Call 995 in Singapore for sudden severe chest, back or abdominal pain, collapse, new weakness, or a suddenly painful, cold or weak leg. These symptoms can signal serious aortic or circulation problems. Tell the emergency team that you have an aortic graft.

New persistent pain, fever, wound changes or a clear decline in walking ability also needs timely advice from the treating team. The appropriate urgency depends on the symptoms. A routine surveillance booking is not a route for managing an acute emergency.

Common follow-up questions

Can I stop scans after several normal results?

Do not stop on your own. Endovascular repairs require long-term surveillance because the device and aorta can change. The specialist may adjust the interval and scan method to your current findings and health.

What if I have lost track of follow-up?

Contact your treating team to re-establish the plan, even if you feel well. Keep a copy of your operation summary, implant details, scan reports and next appointment. The aortic awareness guide offers questions to bring.

Arrange an aortic follow-up review in Singapore

For a planned review or second opinion, contact Andrew Choong Vascular Surgery at Mount Elizabeth Novena Specialist Centre. Bring actual scan images as well as reports. The EVAR video explains the basic graft principle; your repair records determine the follow-up you need.