Pulmonary Embolism Complicating Deep Vein Thrombosis
A 62-year-old man had ultrasonography confirming a femoropopliteal deep vein thrombosis, and no treatment has been started. Two hours later he develops pleuritic chest pain and breathlessness. Blood pressure is 126/78 mm Hg and oxygen saturation 92% on room air. CT pulmonary angiography shows filling defects in segmental pulmonary arteries with a normal-sized right ventricle, and high-sensitivity troponin is normal. What is the most appropriate next step in management?
- A.Systemic thrombolysis with alteplase
- B.Therapeutic-dose low molecular weight heparinCorrect
- C.Inferior vena cava filter placement
- D.Surgical pulmonary embolectomy
Explanation
This patient has a confirmed deep vein thrombosis that has embolised to the pulmonary arteries, but he is haemodynamically stable with a normal blood pressure, a normal-sized right ventricle and a normal troponin, which places him in the low-risk category. For low-risk and intermediate-risk pulmonary embolism, prompt therapeutic anticoagulation is the treatment that prevents clot propagation and further embolisation while endogenous fibrinolysis clears the existing thrombus. Low molecular weight heparin, fondaparinux, or a direct oral anticoagulant such as rivaroxaban or apixaban are all acceptable, and anticoagulation should not be delayed once the diagnosis is confirmed. Systemic thrombolysis reduces mortality only in high-risk (massive) pulmonary embolism defined by persistent hypotension or shock, and carries roughly a 2% risk of intracranial haemorrhage, so it is not justified in a normotensive patient. An inferior vena cava filter is reserved for patients in whom anticoagulation is absolutely contraindicated, such as active major bleeding or recent neurosurgery, or for recurrent embolism despite adequate anticoagulation. Surgical or catheter embolectomy is a rescue option for high-risk embolism when thrombolysis fails or is contraindicated. Risk stratification using clinical scores such as the Wells or revised Geneva score guides diagnostic testing, while haemodynamic status and right ventricular assessment guide treatment intensity. Anticoagulation is then continued for at least 3 months, with duration determined by whether the event was provoked or unprovoked.
Why each option
- A.
- Thrombolysis is indicated only for high-risk pulmonary embolism with persistent hypotension or shock, given the substantial bleeding risk.
- B.
- Correct. Haemodynamically stable pulmonary embolism is treated with prompt therapeutic anticoagulation, which prevents propagation and recurrence.
- C.
- A vena cava filter is used only when anticoagulation is contraindicated or has failed; this patient can safely be anticoagulated.
- D.
- Surgical embolectomy is reserved for massive embolism when thrombolysis fails or is contraindicated.
Reference: ESC 2019 Guidelines on the Diagnosis and Management of Acute Pulmonary Embolism; UpToDate 2025, Treatment of acute pulmonary embolism
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