What is the recommended management for a penetrating atherosclerotic ulcer of the infrarenal aorta?

Management of Penetrating Atherosclerotic Ulcer of the Infrarenal Aorta

For penetrating atherosclerotic ulcer (PAU) of the infrarenal aorta, initiate immediate aggressive medical therapy with intravenous beta-blockers targeting heart rate ≤60 bpm and systolic blood pressure <120 mmHg, followed by endovascular repair (EVAR) for symptomatic cases or those with high-risk imaging features. 1, 2, 3

Immediate Medical Management (All Patients)

Medical therapy is mandatory for all patients with PAU regardless of location or severity and must be initiated immediately upon diagnosis. 1, 2

Hemodynamic Control Protocol

Heart Rate Control (First Priority):

• Target heart rate ≤60 beats per minute using intravenous beta-blockers as first-line therapy 2, 3
• If beta-blockers are contraindicated, use non-dihydropyridine calcium channel blockers as an alternative 2, 3
• Critical pitfall: Never initiate vasodilators before achieving heart rate control, as this provokes reflex tachycardia that increases aortic wall stress 2, 3

Blood Pressure Control (Second Priority):

• Target systolic blood pressure <120 mmHg and diastolic <80 mmHg 2, 3
• After achieving adequate heart rate control, if systolic BP remains >120 mmHg, add intravenous ACE inhibitors and/or other vasodilators 2

Pain Management:

• Provide adequate analgesia as part of initial management 3

Diagnostic Confirmation and Risk Stratification

Imaging:

• Obtain contrast-enhanced CT as the diagnostic technique of choice (96% sensitivity for detecting associated intramural hematoma) 2, 3
• Look for the classic "mushroom-shaped protrusion" with overhanging edges penetrating through the internal elastic lamina 3

High-Risk Imaging Features Requiring Intervention:

• Maximum PAU width ≥13-20 mm 1, 3
• Maximum PAU depth ≥10 mm 1, 3
• Significant growth of PAU width or depth >5 mm/year 1
• PAU associated with a saccular aneurysm 1
• PAU with increasing pleural effusion 1
• Aortic diameter >42 mm at the site of PAU 4
• Associated intramural hematoma 5

Indications for Endovascular Intervention

Absolute Indications (Proceed to EVAR):

• Any symptomatic PAU (pain, shock, contained rupture) 1, 4, 6
• Complicated PAU with recurrent/persistent pain despite medical therapy 1, 5
• Hematoma expansion on serial imaging 1, 5
• Periaortic hematoma 1, 5
• Intimal disruption 5

Relative Indications (Should Consider EVAR):

• Asymptomatic PAU with any high-risk imaging features listed above 1, 4
• Aortic diameter >50 mm 4
• Concomitant aortic pathology 4

Endovascular Repair Technique

Technical Approach:

• Deploy endoprostheses according to standard elective EVAR anatomical requirements via femoral access 6
• For infrarenal PAU, standard aortic stent grafts are appropriate 6
• If PAU involves visceral vessel origins (paraceliac), use custom-made fenestrated endografts with fenestrations for celiac trunk, superior mesenteric artery, and renal arteries 7

Expected Outcomes:

• Technical success rate approaches 100% 6, 8
• 30-day mortality approximately 5% for endovascular repair (compared to higher mortality with open surgery or medical management alone) 4, 6
• In-hospital mortality approximately 10.5% 6
• 1-year PAU-related mortality 10.5% 6

Conservative Management (Highly Selected Cases Only)

Criteria for Conservative Management:

• Small asymptomatic PAU with NO high-risk features 1, 4
• Patient must be suitable for close surveillance 1

Surveillance Protocol:

• Imaging (CT or MRI) at 1 month after diagnosis 2, 3
• Then at 3,6, and 12 months 3
• Annually thereafter if stable 3
• Important: 13% of conservatively managed patients demonstrate progression requiring subsequent intervention 4

Long-Term Medical Management (All Patients)

Blood Pressure Control:

• Continue strict blood pressure control (systolic <120 mmHg) indefinitely 2, 3

Lipid Management:

• LDL-C reduction by ≥50% from baseline with goal <55 mg/dL (<1.4 mmol/L) using moderate-to-high intensity statins 2, 3

Antiplatelet Therapy:

• Low-dose aspirin 75-162 mg daily to reduce cardiovascular event risk 2, 3

Post-Intervention Surveillance

For Patients Who Undergo EVAR:

• 9% require reintervention after initial endovascular surgery 4
• Continue regular imaging surveillance to detect endoleaks or device-related complications 6
• Maintain lifelong medical therapy as outlined above 2, 3

Key Clinical Pitfalls to Avoid

• Never delay intervention for symptomatic PAU: Symptom onset indicates PAU expansion with tunica adventitia involvement and imminent rupture risk 1, 2
• Do not underestimate infrarenal PAU: While most PAU occur in the descending thoracic aorta (>90%), infrarenal PAU carries similar rupture risk when symptomatic or with high-risk features 1, 6
• Avoid open surgery when EVAR is anatomically feasible: Early mortality is lowest with endovascular interventions (5%) compared to open surgical management 4
• Do not ignore asymptomatic PAU: These require risk stratification and surveillance, as 13% progress to requiring intervention 4