What is the management approach for Pulmonary Embolism (PE)?

Management of Pulmonary Embolism (PE)

Direct oral anticoagulants (DOACs) are the preferred first-line treatment for intermediate or low-risk pulmonary embolism, while high-risk PE with hemodynamic instability requires immediate thrombolytic therapy. 1

Risk Stratification

Risk stratification is essential for determining the appropriate management approach:

1. High-risk PE (massive): Hemodynamically unstable patients (hypotension, shock)
2. Intermediate-risk PE (submassive): Hemodynamically stable with evidence of right ventricular dysfunction
3. Low-risk PE: Hemodynamically stable without right ventricular dysfunction

Treatment Algorithm

1. High-Risk PE (with hemodynamic instability)

• First-line: Systemic thrombolytic therapy 1
  • rtPA (Alteplase) is preferred over streptokinase due to shorter infusion time, lower risk of hypotension, and fewer allergic reactions
• If thrombolysis is contraindicated or fails: Surgical pulmonary embolectomy 1
• Anticoagulation: Start unfractionated heparin (UFH) with thrombolysis

2. Intermediate or Low-Risk PE

• First-line: Direct oral anticoagulants (DOACs) 1

  • Apixaban: 10 mg twice daily for 7 days, followed by 5 mg twice daily 1, 2
  • Rivaroxaban: 15 mg twice daily for 21 days, followed by 20 mg once daily 1, 3
  • Dabigatran: 150 mg twice daily after ≥5 days of initial LMWH 1
  • Edoxaban: 60 mg once daily (30 mg once daily if CrCl 30-50 mL/min or body weight <60 kg) after ≥5 days of initial LMWH 1

• Alternative: Vitamin K antagonists (e.g., Acenocoumarol)

  • Must be overlapped with parenteral anticoagulation until INR reaches 2.0-3.0 (target 2.5) 1
  • Requires regular INR monitoring

Parenteral Anticoagulation

• LMWH or fondaparinux: Preferred over UFH for initial parenteral anticoagulation 1
• UFH: Consider for patients with severe renal impairment or when rapid reversal may be needed
  • Dose adjustment based on aPTT monitoring (target 1.5-2.3× control) 1

Duration of Anticoagulation

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

• Indefinite treatment with vitamin K antagonists (not DOACs) 1

Outpatient Management

Low-risk PE patients can be managed as outpatients if they meet all criteria:

• No hemodynamic instability
• No need for thrombolysis or embolectomy
• No severe pain requiring IV analgesia
• No high bleeding risk
• Oxygen saturation ≥90%
• No severe renal or liver disease
• No social barriers to outpatient care 1

Follow-up

• 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

• Never discontinue anticoagulation prematurely as it increases the risk of thrombotic events 2, 3
• Temporary interruption for surgery: Stop apixaban at least 48 hours prior to procedures with moderate/high bleeding risk and 24 hours prior to low bleeding risk procedures 2
• DOACs are contraindicated in pregnancy, antiphospholipid syndrome, and severe liver disease 1
• Monitor for drug interactions with medications metabolized through CYP3A4 enzyme or P-glycoprotein 1

Vena Cava Filters

Consider only in patients with absolute contraindications to anticoagulation or recurrent PE despite adequate anticoagulation 4