45-year-old patient who was incidentally found on ultrasound (US) to have an abdominal aortic aneurysm (AAA)…

Explanation

Core Concept: Abdominal aortic aneurysm (AAA) management is based on size and growth rate. For AAA 4.0-5.4 cm, the risk of rupture is low (<1%/year), and surveillance is preferred over surgery. Surgical repair (open or EVAR) is indicated when AAA reaches ≥5.5 cm in men (≥5.0 cm in women), grows >0.5 cm in 6 months, or becomes symptomatic.

Clinical Presentation:

• Usually asymptomatic (incidental finding).
• May present with deep, boring abdominal/back pain if expanding.
• Pulsatile abdominal mass on examination.
• Complications: Rupture (catastrophic hemorrhage, 80-90% mortality), distal embolization, aortoenteric fistula.

Diagnosis:

• First-line tool: Abdominal ultrasound (screening and surveillance).
• Gold standard: CT angiography for pre-operative planning, measuring maximum diameter, and assessing morphology for EVAR suitability.

Management:

• Acute: For 4.5 cm AAA: No immediate intervention. Cardiovascular risk modification (smoking cessation, statin, antiplatelet, BP control).
• Long-term/Definitive: Surveillance ultrasound every 12 months for AAA 4.0-5.4 cm (some guidelines: every 6-12 months). Surgical repair (EVAR or open repair) when threshold reached (≥5.5 cm) or rapid expansion (>0.5 cm/6 months).