Question

An inferior vena cava (IVC) filter is used for all of the following purposes except:

• A. To reduce symptoms
• B. Negligible size of emboli
• C. To prolong life
• D. To prevent progression of native blood vessel disease

Hint:

Think about what a mesh filter can and cannot trap.

Answer 1

The Correct Option is B

Step 1: Purpose of an IVC filter. An IVC filter is placed in patients with venous thromboembolism (deep vein thrombosis or pulmonary embolism) who cannot receive anticoagulation, or who develop recurrent emboli despite adequate anticoagulation. Its goal is to mechanically trap large clots before they reach the pulmonary circulation.

Step 2: What the filter actually achieves. By catching sizeable thrombi, the filter reduces symptomatic and life-threatening pulmonary embolism, thereby helping to reduce symptoms and prolong life. It also limits ongoing thrombotic burden in the vascular bed.

Step 3: Why option (b) is the exception. An IVC filter cannot stop small or microscopic emboli; tiny clots simply pass through the gaps of the filter mesh. So a filter has no effect on emboli of negligible size. This makes "negligible size of emboli" the statement that is NOT a use of the device.

Step 4: Conclusion. The correct answer is option (b).