From the Guidelines
For patients with subsegmental pulmonary embolism (PE) and no proximal DVT, I recommend clinical surveillance over anticoagulation for those with low risk for recurrent VTE, and anticoagulation over clinical surveillance for those with high risk for recurrent VTE. This approach is based on the most recent guidelines from the Chest journal, which suggest that clinical surveillance is a viable option for patients with low risk of recurrence, while anticoagulation is preferred for those with high risk 1.
Key Considerations
- The decision to use anticoagulation or clinical surveillance should be based on the patient's risk factors for recurrent VTE, as well as their individual risk of bleeding complications.
- Clinical surveillance involves patient education to recognize signs and symptoms of progressive thrombosis, and regular follow-up to monitor for complications.
- Anticoagulation therapy, such as direct oral anticoagulants (DOACs) or low molecular weight heparin (LMWH), can be used to prevent further clot formation and reduce the risk of recurrence.
- The European Heart Journal guidelines also support the use of anticoagulation in patients with cancer and subsegmental PE, with a preference for LMWH or specific DOACs (edoxaban or rivaroxaban) 1.
Treatment Options
- For patients with low risk of recurrence, clinical surveillance may be sufficient, with regular follow-up to monitor for complications.
- For patients with high risk of recurrence, anticoagulation therapy should be initiated, with options including DOACs (such as apixaban, rivaroxaban, or edoxaban) or LMWH (such as enoxaparin) followed by warfarin.
- The choice of anticoagulant should be based on individual patient factors, including their risk of bleeding complications and their preference.
Monitoring and Follow-up
- Regular follow-up is essential to monitor for bleeding complications and to assess treatment efficacy.
- Patients should be educated to recognize signs and symptoms of progressive thrombosis, and to seek medical attention immediately if they occur.
- The need for extended therapy should be evaluated based on risk factors for recurrence versus bleeding risk, with periodic reassessment of the risk-to-benefit ratio of continued anticoagulant treatment.
From the Research
Recent Trials on Subsegmental PE
- Recent studies have investigated the treatment of subsegmental pulmonary embolism (SSPE), with a focus on anticoagulant therapy 2, 3, 4.
- The use of direct oral anticoagulants (DOACs) has been explored as a potential treatment option for PE, offering advantages such as oral availability, rapid onset of action, and predictable pharmacokinetics 5.
- However, the effectiveness and safety of anticoagulation therapy versus no intervention in patients with SSPE or incidental SSPE remains unclear, with no randomised controlled trials meeting the inclusion criteria in recent reviews 2, 3, 4.
Clinical Context and Anticoagulation
- A study published in 2023 found that anticoagulation for SSPE is controversial, and the decision to anticoagulate is often influenced by the clinical context, including risk factors, alternative indications, and illness severity 6.
- The study found that patients who received anticoagulation had a different clinical context, with higher rates of previous venous thromboembolism, recent surgery, and elevated serum D-dimer, and were more likely to require inpatient care 6.
- The study also found that SSPE is associated with high mortality, regardless of anticoagulation, due to coexistent disease processes rather than SSPE itself 6.
Need for Further Research
- Despite the availability of DOACs and their potential benefits, further research is needed to determine the effectiveness and safety of anticoagulation therapy in patients with SSPE or incidental SSPE 2, 3, 5, 4.
- Well-conducted randomised controlled trials are required to inform practice decisions and provide evidence-based guidance for the treatment of SSPE 2, 3, 4.