What is the role of Novel Oral Anticoagulants (NOACs) in patients with peripartum cardiomyopathy (PPCM) and deep vein thrombosis (DVT)?

Role of NOACs in Patients with Peripartum Cardiomyopathy and DVT

NOACs are appropriate for postpartum treatment of DVT in patients with peripartum cardiomyopathy (PPCM), particularly when left ventricular ejection fraction (LVEF) is <35%, but should be avoided during pregnancy when low molecular weight heparin (LMWH) is preferred. 1, 2, 3

Patient Selection for NOACs in PPCM with DVT

Timing Considerations

• During pregnancy: NOACs are contraindicated due to potential placental crossing 2
  • LMWH is the preferred anticoagulant during pregnancy
• Postpartum period: NOACs can be safely used after delivery 3

LVEF-Based Recommendations

• LVEF <35%: Strong recommendation for anticoagulation to prevent thromboembolism 4
• LVEF 35-40%: Consider anticoagulation based on additional risk factors
• LVEF >40%: Anticoagulation may not be necessary unless other risk factors present

Risk Assessment

• Complete evaluation before NOAC initiation should include:
  • Complete blood count
  • PT, aPTT
  • Renal function (creatinine clearance calculation)
  • Liver function tests
  • Assessment of bleeding risk factors 2

NOAC Selection and Dosing

Preferred NOACs for DVT

1. Rivaroxaban: FDA-approved for DVT treatment 1, 5

   • Initial: 15 mg twice daily for 21 days
   • Maintenance: 20 mg once daily
   • Dose adjustment to 15 mg daily if CrCl 15-50 mL/min

2. Apixaban: FDA-approved for DVT treatment 1

   • Initial: 10 mg twice daily for 7 days
   • Maintenance: 5 mg twice daily
   • Consider 2.5 mg twice daily for extended therapy

3. Edoxaban: After initial parenteral anticoagulation 1

   • 60 mg once daily
   • 30 mg once daily if CrCl 15-50 mL/min or body weight ≤60 kg

4. Dabigatran: After initial parenteral anticoagulation 1

   • 150 mg twice daily

Duration of Therapy

• Minimum: 3 months for provoked DVT 1
• Extended therapy: Consider for PPCM patients with persistent reduced LVEF (<35%) until EF recovery 3, 4
• No need to change anticoagulant after initial 3 months if well-tolerated 1

Contraindications and Precautions

Absolute Contraindications

• Severe renal impairment (CrCl <30 mL/min) 2
• Active major bleeding
• Pregnancy or breastfeeding
• Mechanical heart valves

Relative Contraindications/Cautions

• Moderate renal impairment (dose adjustment required)
• Liver disease with coagulopathy
• Concomitant antiplatelet therapy (increased bleeding risk) 1
• Strong CYP3A4 and P-glycoprotein inhibitors/inducers 2

Monitoring and Follow-up

• Initial follow-up after 1 month, then every 3 months 2
• Monitor:
  • Renal function
  • Liver function
  • Signs/symptoms of bleeding
  • Medication adherence
  • LVEF recovery (may determine duration of therapy)

Common Pitfalls to Avoid

1. Inappropriate dosing: Failure to adjust dose based on renal function
2. Overlooking drug interactions: Particularly with medications affecting CYP3A4 and P-glycoprotein 1
3. Inadequate patient education: NOACs have short half-lives, making adherence critical 2
4. Combining with antiplatelet therapy without clear indication: Significantly increases bleeding risk 1
5. Failure to transition appropriately: When switching between anticoagulant regimens 1

Special Considerations

• Bromocriptine treatment: If used for PPCM, may increase thrombotic risk; ensure adequate anticoagulation 3, 4
• Procedural management: For patients requiring procedures, discontinue NOACs at least 48 hours beforehand for procedures where hemostatic control is essential 1
• Reversal strategies: Limited reversal agents available for NOACs; factor this into risk assessment 1

NOACs offer an effective alternative to traditional vitamin K antagonists for DVT treatment in PPCM patients postpartum, with comparable or better efficacy and reduced risk of intracranial bleeding 1, 6.