Try it
Pathology · Haemodynamics: paradoxical embolism
Sample itemA 30-year-old with calf swelling suddenly develops hemiparesis. Echocardiography with bubble study shows a patent foramen ovale. Through which mechanism did the stroke occur?
Original practice item, not a recalled exam question. Nothing here is recorded.
The answer and the reasoning
B. Paradoxical embolus from the venous system
Venous thrombi from the leg can cross a right-to-left shunt such as a patent foramen ovale into the arterial circulation. This causes systemic or cerebral emboli despite a venous source.
Option by option
A. Cholesterol embolus from the aortic arch
Cholesterol emboli arise from ulcerated atheroma in older patients and cause livedo and renal failure.
B. Paradoxical embolus from the venous system (correct)
Correct. A deep vein thrombus crossing a septal defect becomes an arterial embolus.
C. Fat embolus from long bone fracture
Fat emboli follow fractures and cause lung, brain and skin signs, and no calf swelling.
D. Embolus from a left ventricular mural thrombus
A left ventricular thrombus arises after myocardial infarction and does not relate to calf swelling.
Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.
More Pathology questions
- Haemodynamics: paradoxical embolismA 30-year-old woman with a recent calf deep vein thrombosis develops sudden right-sided…
- HaematopathologyBinucleate 'owl-eye' cells that stain for CD15 and CD30 are characteristic of which cond…
- NeuropathologyEosinophilic intracytoplasmic inclusions in the pigmented neurons of the substantia nigr…
- HaemodynamicsWhich of the following is NOT a component of Virchow's triad for thrombosis?