skip to main content

SVC Obstruction — FRCA Final MCQ

Instant feedback + full explanation. One question, done properly.

HardPreoperative AssessmentSVC ObstructionFRCA Final

A 72-year-old woman with breast cancer has an implantable venous access device entering via the right subclavian vein. During chemotherapy she develops acute dyspnoea, facial and neck plethora, right arm swelling and distended superficial veins over the upper chest; the symptoms worsen when she lies supine. Contrast-enhanced CT shows thrombus surrounding the catheter and extending from the right subclavian vein through the brachiocephalic vein into the superior vena cava, causing severe luminal narrowing. Which diagnosis and mechanism best explain this presentation?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: A — Thrombotic superior vena cava obstruction caused by the venous access device

The diagnosis is catheter-associated thrombotic superior vena cava obstruction. Facial and neck plethora, ipsilateral arm oedema, superficial venous distension and deterioration when supine indicate impaired venous drainage from the head and upper limb. CT confirms that catheter-related thrombus extends into and severely narrows the SVC. Pulmonary embolism can cause acute dyspnoea but does not explain this pattern of upper-body venous congestion. Tamponade and right ventricular failure cause raised systemic venous pressure, usually with more generalised signs, and are not supported by the venous imaging. Anaphylaxis would be suggested by hypotension, urticaria, bronchospasm or acute angioedema and would not account for the demonstrated central venous thrombus.

Reference: Song X, Whittles J, Ding X. Iatrogenic Superior Vena Cava Syndrome With Extensive Thromboembolism Associated With Chronic Indwelling Catheterization. 2025. https://pubmed.ncbi.nlm.nih.gov/40026999/