What is the management of acute pulmonary embolism?

Management of Acute Pulmonary Embolism

Direct oral anticoagulants (DOACs) are the first-line treatment for most patients with low to intermediate-risk pulmonary embolism (PE), while systemic thrombolytic therapy is the first-line treatment for high-risk (massive) PE with hemodynamic instability. 1

Risk Stratification

Risk assessment is crucial for determining the appropriate management strategy:

• High-risk (massive) PE: Characterized by:

  • Collapse/hypotension
  • Unexplained hypoxia
  • Engorged neck veins
  • Often right ventricular gallop 2

• Low to intermediate-risk PE: Use validated tools like:

  • Pulmonary Embolism Severity Index (PESI)
  • Simplified PESI 1

Management Algorithm Based on Risk

1. High-Risk (Massive) PE with Hemodynamic Instability

• Cardiac arrest:

  • Initiate CPR
  • Administer 50 mg alteplase IV
  • Reassess after 30 minutes 2

• Deteriorating condition:

  • Contact consultant
  • Administer 50 mg alteplase IV 2

• Stable but high-risk:

  • Administer 80 units/kg heparin IV
  • Arrange urgent echocardiography or CTPA if deterioration occurs
  • For confirmed massive PE in stable patients, give alteplase 100 mg IV over 90 minutes 2
  • Follow thrombolysis with unfractionated heparin after 3 hours, preferably weight-adjusted 2

2. Low to Intermediate-Risk PE

• Initial anticoagulation:

  • DOACs are preferred over vitamin K antagonists (VKAs) 1
  • Recommended DOAC options:
    • Apixaban: 10 mg twice daily for 7 days, then 5 mg twice daily
    • Rivaroxaban: 15 mg twice daily for 21 days, then 20 mg once daily
    • Dabigatran: 150 mg twice daily after initial LMWH
    • Edoxaban: 60 mg once daily (30 mg once daily if CrCl 30-50 mL/min or body weight <60 kg) 1

• If DOACs are contraindicated:

  • Low molecular weight heparin (LMWH) or fondaparinux is preferred over unfractionated heparin (UFH) 1

Special Populations

Cancer Patients

• LMWH for at least 6 months, followed by continuous anticoagulation while cancer is active 1

Pregnant Patients

• LMWH is the treatment of choice
• DOACs and vitamin K antagonists are contraindicated 1

Antiphospholipid Syndrome

• VKAs are recommended, not DOACs
• Indefinite treatment is advised 1

Renal Impairment

• Patients with CrCl <30 mL/min may not be suitable for DOACs 1
• Rivaroxaban should be avoided in patients with CrCl <15 mL/min 3

Hepatic Impairment

• Avoid DOACs in moderate to severe liver disease 1, 3

Duration of Anticoagulation

• PE with major transient/reversible risk factor: 3 months
• Unprovoked PE or persistent risk factors: Extended treatment (>3 months)
• Recurrent PE: Indefinite anticoagulation 1

Outpatient Management

Outpatient treatment may be considered if:

• Patient is not unduly breathless
• No medical or social contraindications
• Efficient protocol is in place 2
• No hemodynamic instability, need for thrombolysis or embolectomy
• No severe pain requiring IV analgesia
• No high bleeding risk
• Oxygen saturation ≥90% 1

Follow-up and Monitoring

• Regular clinical follow-up at 3-6 months to assess:
  • Medication adherence
  • Bleeding complications
  • Signs of chronic thromboembolic pulmonary hypertension (CTEPH)
  • Need for extended anticoagulation 1

Important Cautions

• DOACs are not recommended for patients with triple-positive antiphospholipid syndrome 3
• DOACs are not recommended for patients with prosthetic heart valves 3
• Initiation of DOACs is not recommended acutely as an alternative to unfractionated heparin in patients with PE who present with hemodynamic instability 3
• Contraindications to thrombolysis should be ignored in life-threatening PE 2

By following this evidence-based approach to PE management, clinicians can optimize outcomes while minimizing risks of recurrent thromboembolism, bleeding complications, and long-term sequelae.