What is the typical treatment for a patient with pulmonary embolism?

Treatment of Pulmonary Embolism

The standard treatment for pulmonary embolism (PE) involves risk stratification based on hemodynamic stability, followed by prompt anticoagulation with preference for NOACs in most patients, with systemic thrombolysis reserved for high-risk PE patients with hemodynamic instability. 1, 2

Risk Stratification

• PE should be classified as high-risk (with shock/hypotension), intermediate-risk (hemodynamically stable with right ventricular dysfunction), or low-risk (hemodynamically stable without right ventricular dysfunction) to guide treatment decisions 2
• Initiate anticoagulation immediately while diagnostic workup is in progress for patients with high or intermediate clinical probability of PE 1

Initial Management by Risk Category

High-Risk PE (with shock or hypotension)

• Immediately start unfractionated heparin (UFH) with a weight-adjusted bolus injection 1
• Administer systemic thrombolytic therapy unless contraindicated 1
• Consider surgical pulmonary embolectomy when thrombolysis is contraindicated or has failed 1
• Percutaneous catheter-directed treatment should be considered when thrombolysis is contraindicated or has failed 1
• Norepinephrine and/or dobutamine should be used to correct hypotension 2
• Extracorporeal membrane oxygenation (ECMO) may be considered in combination with surgical embolectomy or catheter-directed treatment for patients with refractory circulatory collapse 1

Intermediate or Low-Risk PE

• Low molecular weight heparin (LMWH) or fondaparinux is recommended over UFH for initial parenteral anticoagulation 1
• When oral anticoagulation is started, a non-vitamin K antagonist oral anticoagulant (NOAC) such as apixaban, dabigatran, edoxaban, or rivaroxaban is preferred over vitamin K antagonists (VKAs) 1
• Rescue thrombolytic therapy is recommended if hemodynamic deterioration occurs while on anticoagulation 1
• Routine use of primary systemic thrombolysis is not recommended for intermediate or low-risk PE 1

Anticoagulation Protocol

• For high-risk PE: UFH with an initial bolus of 80 U/kg or 5,000-10,000 units, followed by continuous infusion of 18 U/kg/h, adjusted to maintain aPTT 1.5-2.5 times control 2
• When using VKAs, overlap with parenteral anticoagulation until an INR of 2.5 (range 2.0-3.0) is reached 1
• NOACs are contraindicated in patients with severe renal impairment, during pregnancy and lactation, and in patients with antiphospholipid antibody syndrome 1

Duration of Treatment

• All patients require a minimum of 3 months of therapeutic anticoagulation 3
• For PE secondary to a major transient/reversible risk factor, consider discontinuing anticoagulation after 3 months 3
• For unprovoked PE, extended anticoagulation beyond 3 months should be considered indefinitely due to high recurrence risk 3
• Rivaroxaban is FDA-approved for treatment of PE and reduction in risk of recurrence of DVT and/or PE 4

Special Considerations

• Inferior vena cava (IVC) filters should be considered in patients with absolute contraindications to anticoagulation or in cases of PE recurrence despite therapeutic anticoagulation 1
• Routine use of IVC filters is not recommended 1
• Carefully selected patients with low-risk PE should be considered for early discharge and home treatment 1
• Follow-up examination after 3-6 months of anticoagulation is recommended to assess for recurrence, bleeding complications, and persistent symptoms 3
• If symptoms persist, implement diagnostic workup to exclude chronic thromboembolic pulmonary hypertension (CTEPH) 3

Common Pitfalls and Caveats

• Premature discontinuation of anticoagulation increases risk of thrombotic events; if discontinuation is necessary, consider coverage with another anticoagulant 4
• Risk of spinal/epidural hematoma in patients receiving neuraxial anesthesia or undergoing spinal puncture while on anticoagulation 4
• Failure to achieve adequate anticoagulant response (APTT >1.5 times control) with heparin is associated with high risk of recurrent venous thromboembolism 5
• Fluid challenges may worsen hypotension in high-risk PE patients with right ventricular overload; consider vasopressors instead 6