The Correct Answer is B!

 

A 68-year-old man with a history of hypertension, hyperlipidemia, and former 20-pack-year smoker presents to the clinic for a routine physical exam. He feels well, and his review of systems is negative. His current medications include hydrochlorothiazide and atorvastatin. 

On exam, his heart rate is 65 beats per minute, blood pressure is 125/70 mmHg, and the rest of the physical exam is unremarkable. Given his age and smoking history, a screening abdominal ultrasound is ordered and reveals a 4.0 cm infrarenal abdominal aortic aneurysm.

Which of the following is the best management strategy?

A) No repeat imaging unless symptoms occur

B) Repeat imaging in 6-12 months

C) Repeat imaging in 1-3 months

D) Refer the patient for surgical repair

Rationale:

Based on the patient’s age, sex, and smoking history, screening is correctly performed in this case. Based on the U.S. Preventive Services Task Force guideline, one-time screening for abdominal aortic aneurysm (AAA) is recommended for men aged 65-75 who have ever smoked. There is also a weaker recommendation for screening in men aged 65-75 who have never smoked but have risk factors such as the family history of AAA in first-degree relative, obesity, hypercholesterolemia, hypertension, and history of another vascular disease (other vascular aneurysms, coronary artery disease, cerebrovascular disease, atherosclerosis).

Because the risk of rupture is dependent on size, once AAA is identified, size determines the management strategy. According to the ACCF/AHA 2011 guideline, patients with AAAs measuring 5.5 cm or larger should undergo repair. Patients with AAAs measuring 4.0-5.4 cm should be monitored by ultrasound or CT every 6-12 months, and those with AAAs <4.0 cm can be monitored by ultrasound every 2-3 years. Similarly, the Society for Vascular Surgery 2009 practice guidelines recommend monitoring at 12-month intervals for patients with AAA of 3.5-4.4 cm and 6-month intervals for those with AAA of 4.5-5.4 cm. In patients with AAAs measuring 3.0-3.4 cm, monitoring is recommended at 3-year intervals, and AAAs <3.0 cm can be monitored at 5-year intervals.

References

LeFevre ML, Siu AL, Peters JJ, et al. Screening for abdominal aortic aneurysm: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2014;161(4): 281-290.

Chaikof EL, Brewster DC, Dalman RL, et al. The care of patients with an abdominal aortic aneurysm: the Society of Vascular Surgery practice guidelines. J Vasc Surg. 2009;50(Suppl 4):S2-S49.

Rooke TW, Hirsch AT, Misra S, et al. Management of patients with peripheral artery disease (compilation of 2005 and 2011 ACCF/AHA guideline recommendations): a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2013;61(14):1555-1570.

Buy Internal Medicine Essentials