Abdomen, Pelvis, and Perineun

Pathology
Pathogenesis
Management & Determining the Cause
Study Question

As the person uses his or her arm repeatedly and the axillo-subclavian vein is compressed, the vein becomes inflamed. The condition develops when a vein in the armpit (the axilla) or in the front of the shoulder (the subclavian vein) is compressed by the collarbone (clavicle), the first rib, or the surrounding muscle.

Over time, fibrous tissue builds up in the vein. The inside of the vein eventually becomes too narrow to allow normal blood flow. As a result, a blood clot forms.

It is considered a type of thoracic outlet syndrome.

Determine Size by Ultrasound

Image result for ultrasound aorta

Measure the diameter of the outside wall in a posterior-anterior direction and a right to left direction.

< 5 cm

> 5 cm

Nondiagnostic

A 62-year-old man presents with an asymptomatic abdominal aortic aneurysm (AAA) measuring 4.8 cm in diameter. The patient’s past medical history is significant for hypertension and stable angina. He has a 40-pack-year smoking history. His current medications include aspirin, a beta-blocker, and nitrates. The patient describes himself as an active man who just retired and plays 18-holes of golf two times a week. On examination, the carotid pulses and upper extremity pulses are normal. The abdomen is nontender with a prominent aortic pulse. Pulses in the femoral and popliteal regions are readily palpable and appear more prominent than usual.

Questions

What are the complications associated with this disease process?

Answer

What is the best treatment?

Answer

Clinical Considerations

A 62-year-old man with hypertension and stable angina presents with a 4.8 cm asymptomatic infrarenal AAA. The patient’s physical examination is suggestive of aneursymal disease in the femoral and popliteal arteries.

Based on the current size of his AAA, it is best to just follow the AAA with repeat physical examinations and follow-up ultrasound examinations every 6 months.

The reason for continuing surveillance rather than repairing the AAA at this time is that randomized controlled trials comparing observation vs. elective repairs of small asymptomatic AAA (4.0-5.0 cm) showed that elective repairs were associated with increased 30-day mortality and did not improve patient survival over a mean follow-up period of 20 months. The current recommendations for open or endovascular interventions for AAA are based on size, growth rate, and symptoms; criteria are specifically: (1) Diameter >5.5 cm in men or diameter >5.0 cm in women; (2) Rapid growth of >0.5 cm/6 months; (3) Symptomatic AAA (pain or distal embolism).

Even though intervention for his aneurysm is not currently indicated based on the size and the asymptomatic nature, it is important to educate the patient regarding risk reduction strategies to minimize AAA expansion and rupture. The control of hypertension, hypercholesterolemia, and coronary artery disease seem to be beneficial in reducing the risk of AAA expansion.

In addition, it is important to obtain ultrasound, CT-angiography, or MR-arteriography to assess the femoral and popliteal arteries since the physical examination findings are suspicious for the presence of aneurysmal changes in those areas.

Subclavian Vein Thrombosis

Questions

USMLE Reviewer

Diseases and Disorders