The INCORRECT Statement is B: Surgical repair when the diameter exceeds 7.5 cm
Statement B is definitively wrong—the threshold for elective repair of an infrarenal abdominal aortic aneurysm (AAA) is ≥5.5 cm in men, not 7.5 cm. 1
Analysis of Each Statement
Statement A: Risk of rupture is proportional to diameter - CORRECT
This is accurate. The strongest risk factor for AAA rupture is maximal aortic diameter 2. Rupture risk increases progressively: approximately 0.5-5% annually for aneurysms <5 cm, 3-15% for 5-6.9 cm, and ≥30% for aneurysms ≥8 cm 1. For this patient's 4.5 cm aneurysm, the annual rupture risk is approximately 1-2% 3.
Statement B: Surgical repair when diameter exceeds 7.5 cm - INCORRECT
This is dangerously wrong. The 2023 ACC/AHA guidelines provide a Class I, Level A recommendation that repair is indicated when AAA diameter reaches ≥5.5 cm in men or ≥5.0 cm in women 1. Multiple high-quality trials (UKSAT, ADAM, CAESAR, PIVOTAL) established that 5.5 cm is the appropriate threshold, balancing rupture risk against operative risk 1, 4. Waiting until 7.5 cm would expose patients to unacceptably high rupture rates (≥30% annually for aneurysms ≥8 cm) 1.
For this 72-year-old man with a 4.5 cm aneurysm, surveillance with ultrasound or CT every 6 months is recommended 5. Repair becomes indicated when the aneurysm reaches 5.5 cm.
Statement C: Endovascular stent placement if open repair contraindicated - CORRECT
Endovascular aneurysm repair (EVAR) is an established alternative to open surgical repair, particularly for patients with significant comorbidities that increase operative risk 2. While short-term mortality and morbidity are lower with EVAR compared to open repair, long-term survival is similar, and EVAR requires ongoing surveillance for endoleaks and potential reintervention 2, 6.
Statement D: Frequent association with atherosclerotic coronary artery disease - CORRECT
AAA is strongly associated with atherosclerotic disease in other vascular beds. The guidelines specifically note that risk of AAA increases with three-vessel coronary artery disease 5. This patient population commonly has concurrent coronary, cerebrovascular, and peripheral arterial disease, reflecting the systemic nature of atherosclerosis.
Statement E: Treat symptomatic coronary disease first, then aortic disease - CORRECT
This represents standard practice for managing coexisting symptomatic coronary artery disease and asymptomatic AAA. When both conditions are present, the symptomatic and immediately life-threatening condition (unstable coronary disease) takes priority. However, this applies specifically to asymptomatic AAA—if the AAA becomes symptomatic or reaches repair threshold (≥5.5 cm), the management sequence must be reassessed based on relative urgency.
Key Clinical Pitfalls
- Never delay repair until 7.5 cm—this exposes patients to catastrophic rupture risk
- For this patient's 4.5 cm aneurysm: surveillance every 6 months is appropriate 5
- Repair is also indicated if growth exceeds 0.5 cm in 6 months, regardless of absolute size 1
- Women have lower thresholds (5.0 cm) due to higher rupture rates at smaller diameters 1, 4