Pulmonary Embolism on Anticoagulation
A 62-year-old woman diagnosed 5 days ago with a proximal deep vein thrombosis is adherent to therapeutic low molecular weight heparin. She now has pleuritic chest pain and breathlessness. She is normotensive with oxygen saturation 94% on room air. Computed tomography pulmonary angiography shows bilateral segmental filling defects with a right to left ventricular ratio of 0.8. Troponin and natriuretic peptide are normal. Which is the most appropriate next step?
- A.Insert a retrievable inferior vena cava filter
- B.Give systemic thrombolysis with alteplase
- C.Proceed to surgical pulmonary embolectomy
- D.Continue the current therapeutic anticoagulationCorrect
Explanation
Risk stratification, not the mere presence of a new embolus, determines treatment in pulmonary embolism. This patient is haemodynamically stable with a normal blood pressure, a normal right ventricular to left ventricular ratio and normal cardiac biomarkers, which places her in the low-risk category, so therapeutic anticoagulation alone is the correct treatment. Segmental emboli commonly arise from an already known proximal deep vein thrombosis during the first days of treatment, before the clot has organised and adhered, and this does not by itself mean treatment failure. Systemic thrombolysis is reserved for high-risk (massive) pulmonary embolism defined by sustained hypotension, shock or cardiac arrest, because it roughly triples the risk of major bleeding and carries a 2 to 3% risk of intracranial haemorrhage. In intermediate-high risk disease with right ventricular dysfunction and raised troponin, the approach is close monitoring with rescue thrombolysis only if deterioration occurs. Surgical or catheter embolectomy is reserved for high-risk patients in whom thrombolysis fails or is contraindicated. An inferior vena cava filter is indicated only when anticoagulation is absolutely contraindicated, such as active major bleeding, or for genuinely recurrent embolism despite documented therapeutic anticoagulation; used inappropriately it increases the long-term risk of recurrent deep vein thrombosis. Adherence, correct dosing and the possibility of occult malignancy or antiphospholipid syndrome should be reviewed before labelling any event true anticoagulation failure.
Why each option
- A.
- A vena cava filter is used when anticoagulation is contraindicated by active bleeding, and it increases long-term recurrent deep vein thrombosis risk.
- B.
- Thrombolysis is indicated only for high-risk pulmonary embolism with hypotension or shock, and carries a substantial risk of major and intracranial haemorrhage.
- C.
- Embolectomy is reserved for high-risk patients when thrombolysis fails or is contraindicated, not for a stable patient with segmental emboli.
- D.
- Correct. A haemodynamically stable patient with a normal right ventricle and normal biomarkers has low-risk pulmonary embolism, for which therapeutic anticoagulation alone is the treatment.
Reference: ESC Guidelines for the Diagnosis and Management of Acute Pulmonary Embolism, 2019
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