Which of the following is the most serious complication of deep vein thrombosis?

• A. Gangrene in the affected limb
• B. Cerebral thrombosis
• C. Pulmonary embolism
• D. Varicose veins

Answer: (C)

When a deep vein thrombosis forms, a piece of the clot can break free and travel through the bloodstream to the lungs. This pulmonary embolism can suddenly block blood flow in the lungs, leading to severe shortness of breath, chest pain, low oxygen levels, and can be life-threatening, especially if the clot is large or the person has other health problems. That immediacy and potential for rapid deterioration is why it’s considered the most serious complication of DVT.

Gangrene in the affected limb is possible with very severe venous obstruction but is far less common and not as immediately dangerous as a pulmonary embolism. Cerebral thrombosis refers to a stroke from an arterial clot in the brain, which isn’t a direct result of a leg DVT. Varicose veins are usually a benign condition and not a dangerous complication of DVT.