Treatment of 11mm Saccular Aneurysm of Intrarenal Aorta
An 11mm saccular aneurysm of the intrarenal (infrarenal) aorta should undergo elective repair, preferably with endovascular aneurysm repair (EVAR) if anatomically suitable, as saccular morphology warrants intervention at the lower threshold of ≥45mm (4.5cm) rather than the standard 55mm threshold used for fusiform aneurysms. 1
Why This Aneurysm Requires Treatment
Your 11mm (1.1cm) aneurysm is well below the intervention threshold, but understanding the treatment paradigm is critical:
Saccular aneurysms have a fundamentally different risk profile than fusiform aneurysms, with the European Society of Cardiology recommending repair at ≥45mm diameter specifically because of their increased rupture risk at smaller sizes. 1
Symptomatic saccular AAAs require urgent repair regardless of size, as 25% of acutely presenting saccular aneurysms are <55mm and 8.4% are <45mm—substantially higher rates than fusiform aneurysms. 1
Research demonstrates that saccular aneurysms grow at approximately 2.8±2.9 mm/year, with decreased calcium burden and increased patient age predicting faster growth. 2
Current Management for Your 11mm Aneurysm
At 11mm, this aneurysm requires surveillance imaging, not immediate intervention:
Obtain baseline CT angiography to precisely measure diameter, assess morphology, and establish baseline for growth monitoring. 3
Surveillance imaging every 6-12 months is appropriate for aneurysms of this size, with more frequent monitoring if risk factors are present (smoking, diabetes, rapid growth). 3
Intervention becomes indicated if:
Treatment Approach When Intervention Threshold is Met
EVAR is the preferred approach when anatomically feasible:
EVAR reduces perioperative mortality to <1% compared to open repair, with significantly reduced 30-day morbidity in high-risk patients. 1
Anatomic suitability must be confirmed with cardiovascular CT showing adequate proximal and distal landing zones (typically ≥15mm of non-aneurysmal aorta) and appropriate iliac access. 3
Life expectancy >2 years is required to justify EVAR, as the procedure requires lifelong surveillance and potential reinterventions. 1
Open surgical repair is indicated when anatomy is unsuitable for EVAR or when patient cannot comply with required long-term imaging surveillance. 3
Critical Post-Intervention Surveillance Requirements
If EVAR is performed, mandatory follow-up includes:
30-day imaging with CT and duplex ultrasound to assess technical success and detect early complications. 3
Surveillance at 6-12 months, then annually for 5 years with CT or duplex ultrasound/contrast-enhanced ultrasound to monitor for endoleaks, graft migration, and aneurysm sac changes. 3, 1
Type I and Type III endoleaks require immediate reintervention to prevent rupture, while Type II endoleaks with sac expansion ≥10mm warrant consideration for embolization. 3
Key Pitfalls to Avoid
Do not wait for the standard 55mm threshold used for fusiform aneurysms—saccular morphology increases rupture risk at smaller diameters. 1
Do not perform EVAR outside manufacturer's instructions for use, as off-label anatomic criteria significantly increase complication rates. 1
Do not neglect post-EVAR surveillance, as endoleaks occur in up to one-third of patients and can lead to continued aneurysm expansion and rupture risk. 1
Do not assume EVAR is appropriate for patients who cannot comply with lifelong imaging surveillance—open repair is preferable in such cases. 3
Additional Considerations
Evaluate for concomitant aneurysms in other vascular beds, as patients with saccular aneurysms may have additional arterial pathology requiring surveillance. 4
Optimize cardiovascular risk factors including smoking cessation, blood pressure control, and statin therapy during surveillance period. 3
Consider referral to a Multidisciplinary Aortic Team at centers with high-volume experience when intervention becomes indicated. 3