Treatment of Pulmonary Embolism
The recommended treatment for pulmonary embolism is immediate anticoagulation, with direct oral anticoagulants (DOACs) preferred over vitamin K antagonists for most patients without contraindications. 1, 2
Risk Stratification
Risk stratification is essential to determine the appropriate treatment approach:
- High-risk PE: Characterized by hemodynamic instability (shock or persistent hypotension) 1, 3
- Intermediate-risk PE: Hemodynamically stable with right ventricular dysfunction and/or elevated cardiac biomarkers 2, 3
- Low-risk PE: Hemodynamically stable without right ventricular dysfunction or elevated cardiac markers 2
Initial Treatment
High-Risk PE (with hemodynamic instability)
- Initiate unfractionated heparin (UFH) without delay, including weight-adjusted bolus injection 1, 3
- Systemic thrombolytic therapy is recommended 1, 3
- If thrombolysis is contraindicated or fails, surgical pulmonary embolectomy is recommended 1
- Percutaneous catheter-directed treatment should be considered when thrombolysis is contraindicated or has failed 1, 3
- Vasopressor support with norepinephrine and/or dobutamine should be considered 1
- Extracorporeal membrane oxygenation (ECMO) may be considered in refractory circulatory collapse 1, 3
Intermediate or Low-Risk PE
- Initiate anticoagulation immediately in patients with high or intermediate clinical probability of PE, even while diagnostic workup is ongoing 1, 2
- For parenteral anticoagulation, low molecular weight heparin (LMWH) or fondaparinux is preferred over UFH for most patients 1, 2
- When starting oral anticoagulation, a DOAC (apixaban, dabigatran, edoxaban, or rivaroxaban) is recommended over vitamin K antagonists (VKAs) for eligible patients 1, 2, 4
- If VKAs are used, overlap with parenteral anticoagulation until an INR of 2.0-3.0 is reached 1, 2
- Routine use of primary systemic thrombolysis is not recommended for intermediate or low-risk PE 1, 3
Special Considerations
Contraindications to DOACs
- DOACs should not be used in patients with: 1, 2
- Severe renal impairment
- Pregnancy and lactation
- Antiphospholipid antibody syndrome
Rescue Therapy
- Rescue thrombolytic therapy is recommended for patients who develop hemodynamic deterioration while on anticoagulation 1, 2
- Surgical embolectomy or catheter-directed treatment should be considered as alternatives to rescue thrombolysis 1
Inferior Vena Cava (IVC) Filters
- IVC filters should be considered in patients with: 1, 2
- Acute PE and absolute contraindications to anticoagulation
- PE recurrence despite therapeutic anticoagulation
- Routine use of IVC filters is not recommended 1
Duration of Treatment
- Therapeutic anticoagulation should be administered for at least 3 months to all patients with PE 2, 5
- After 3 months, patients should be assessed for discontinuation of therapy, indefinite anticoagulation, or extended anticoagulation based on individual risk-benefit assessment 2
Follow-up Care
- Schedule follow-up examination after 3-6 months of anticoagulation to assess for signs of VTE recurrence, bleeding complications, and persistent symptoms 2
- If persistent symptoms are present, diagnostic workup should be implemented to exclude chronic thromboembolic pulmonary hypertension 2
Common Pitfalls to Avoid
- Delaying anticoagulation while awaiting diagnostic confirmation in patients with high clinical probability 2, 5
- Using DOACs in patients with severe renal impairment or antiphospholipid antibody syndrome 1, 2
- Routinely administering thrombolysis for PE without hemodynamic compromise 1, 3
- Losing patients to follow-up after initial treatment, risking missed chronic thromboembolic pulmonary hypertension diagnosis 2