Cardiovascular for PLAB 1

A 58 year old woman has a swollen, painful left calf four days after a long-haul flight. The calf is 4 cm larger than the right, warm and tender along the deep veins, with pitting oedema. She has no erythematous advancing edge and is afebrile. Her Wells score is 3. What is the SINGLE most likely diagnosis?

1. Deep vein thrombosis correct Correct. Unilateral calf swelling more than 3 cm greater than the other side, deep venous tenderness, pitting oedema and a recent immobility risk factor. The absence of fever and of a spreading erythematous edge argues against the cellulitis that is its commonest mimic.
2. Chronic venous insufficiency Bilateral, chronic, with haemosiderin staining and lipodermatosclerosis. A Wells score of 3 with unilateral pitting oedema is acute and unilateral.
3. Lymphoedema Non-pitting, chronic, involving the toes with a positive Stemmer sign. A Wells score of 3 with unilateral pitting oedema is not that.
4. Calf muscle tear Sudden pain during exertion with bruising, and a clear mechanism. A Wells score of 3 with unilateral pitting oedema gives no such history.
5. Cellulitis Spreading erythema with a defined advancing edge, fever and a portal of entry, and it is the differential most often confused with DVT. A Wells score of 3 with unilateral pitting oedema points away from it.

The point: Wells score first. Two or more means DVT is LIKELY: proximal leg vein ultrasound within 4 hours, or interim anticoagulation and a scan within 24 hours. One or less means UNLIKELY: D-dimer, and if negative it is excluded. A D-dimer taken without a Wells score is uninterpretable. It is sensitive, not specific, and rises in infection, malignancy, pregnancy and old age.

Source: NICE NG158 — Venous thromboembolic diseases: diagnosis, management and thrombophilia testing NICE · tier 1, national regulator or guidance

A 58 year old woman has a swollen, painful left calf four days after a long-haul flight. The calf is 4 cm larger than the right, warm and tender along the deep veins, with pitting oedema. She has no erythematous advancing edge and is afebrile. Her Wells score is 3. What is the SINGLE most appropriate initial investigation?

1. D-dimer Only useful where DVT is UNLIKELY on Wells, to rule out. A positive result in that group still needs a scan, and it cannot rule anything in. A Wells score of 3 with unilateral pitting oedema decides whether it helps.
2. CT pulmonary angiogram For suspected pulmonary embolism, not for an isolated swollen leg. A Wells score of 3 with unilateral pitting oedema does not raise that.
3. Proximal leg vein ultrasound correct Correct. A Wells score of 2 or more makes DVT LIKELY, and in that group ultrasound is the test, a D-dimer adds nothing because a negative result would not be enough to rule out. The scan should happen within 4 hours, or she gets interim anticoagulation and a scan within 24.
4. Thrombophilia screen For unprovoked venous thromboembolism where stopping anticoagulation is being considered, and never during the acute event or on anticoagulation. A Wells score of 3 with unilateral pitting oedema makes the timing wrong.
5. Wells score Determines which test to do next and makes the D-dimer interpretable. It comes before anything, and it is the step candidates skip. A Wells score of 3 with unilateral pitting oedema makes it first.

The point: Wells score first. Two or more means DVT is LIKELY: proximal leg vein ultrasound within 4 hours, or interim anticoagulation and a scan within 24 hours. One or less means UNLIKELY: D-dimer, and if negative it is excluded. A D-dimer taken without a Wells score is uninterpretable. It is sensitive, not specific, and rises in infection, malignancy, pregnancy and old age.

Source: NICE NG158 — Venous thromboembolic diseases: diagnosis, management and thrombophilia testing NICE · tier 1, national regulator or guidance

A 58 year old woman has a swollen, painful left calf four days after a long-haul flight. The calf is 4 cm larger than the right, warm and tender along the deep veins, with pitting oedema. She has no erythematous advancing edge and is afebrile. Her Wells score is 3. What is the SINGLE most appropriate immediate management?

1. Investigate for underlying malignancy Her thrombosis is provoked by the flight, so blanket cancer screening is not indicated. History, examination and basic tests are, and anything abnormal there is followed up, and a Wells score of 3 with unilateral pitting oedema here points elsewhere.
2. Direct oral anticoagulant correct Correct. Apixaban or rivaroxaban started immediately on confirmation, for at least three months. Neither needs bridging with heparin, which is the change from the warfarin era that examiners test.
3. Reassure and review in one week Unsafe where DVT is possible. The risk is a fatal pulmonary embolism in the interval. A Wells score of 3 with unilateral pitting oedema makes it wrong.
4. Catheter-directed thrombolysis For extensive iliofemoral thrombosis with limb-threatening ischaemia, phlegmasia. A Wells score of 3 with unilateral pitting oedema meets that.
5. Interim anticoagulation pending the scan Where DVT is likely and the ultrasound cannot be done within 4 hours. A Wells score of 3 with unilateral pitting oedema makes it the safe bridge.

The point: Wells score first. Two or more means DVT is LIKELY: proximal leg vein ultrasound within 4 hours, or interim anticoagulation and a scan within 24 hours. One or less means UNLIKELY: D-dimer, and if negative it is excluded. A D-dimer taken without a Wells score is uninterpretable. It is sensitive, not specific, and rises in infection, malignancy, pregnancy and old age.

Source: NICE NG158 — Venous thromboembolic diseases: diagnosis, management and thrombophilia testing NICE · tier 1, national regulator or guidance