Haemodynamics: pulmonary embolism: practice question

A Pathology question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

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Pathology · Haemodynamics: pulmonary embolism

Sample item

A 45-year-old woman collapses and dies 6 days after a hip replacement. Autopsy shows a large coiled thrombus straddling the bifurcation of the main pulmonary trunk. Where did this thrombus most probably originate?

AThe left ventricle after a silent infarctBDeep veins of the calf and thigh, from which it embolised through the right heartCThe left atrial appendage in atrial fibrillationDSuperficial varicose veins of the leg

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

B. Deep veins of the calf and thigh, from which it embolised through the right heart

Most pulmonary emboli come from deep leg veins (popliteal, femoral, iliac) and a saddle embolus at the bifurcation can cause sudden death by acute right heart failure. Postoperative immobility and orthopaedic surgery are strong risk factors. Left-sided thrombi cause systemic, not pulmonary, emboli.

Option by option

A. The left ventricle after a silent infarct
Left ventricular thrombus embolises into the systemic arterial circulation.
B. Deep veins of the calf and thigh, from which it embolised through the right heart (correct)
Correct. Deep vein thrombi pass through the right heart into the pulmonary arteries.
C. The left atrial appendage in atrial fibrillation
Left atrial thrombi also lead to systemic arterial emboli such as stroke.
D. Superficial varicose veins of the leg
Superficial varicosities rarely embolise because their thrombi are usually adherent and small.

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.

Questions about this Pathology question

What is the answer to this Pathology question?

The best answer is B, Deep veins of the calf and thigh, from which it embolised through the right heart. Most pulmonary emboli come from deep leg veins (popliteal, femoral, iliac) and a saddle embolus at the bifurcation can cause sudden death by acute right heart failure.

Why is "The left ventricle after a silent infarct" not the answer?

Left ventricular thrombus embolises into the systemic arterial circulation.

Why is "The left atrial appendage in atrial fibrillation" not the answer?

Left atrial thrombi also lead to systemic arterial emboli such as stroke.

Why is "Superficial varicose veins of the leg" not the answer?

Superficial varicosities rarely embolise because their thrombi are usually adherent and small.

What concept does this question test?

It tests Haemodynamics: pulmonary embolism in Pathology. Postoperative immobility and orthopaedic surgery are strong risk factors. Left-sided thrombi cause systemic, not pulmonary, emboli.

How hard is this question?

We tag it as a multi-step question: it asks you to combine more than one idea. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Haemodynamics: pulmonary embolism?

Learn each disease as a bundle: cause, key histology, markers, and the clinical hallmark. Then use the flashcards and the other Pathology questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.