What is the treatment for Atrial Fibrillation (Afib) with Rapid Ventricular Response (RVR)?

Treatment of Atrial Fibrillation with Rapid Ventricular Response (AFib RVR)

Beta blockers and calcium channel blockers are the first-line treatments for AFib with RVR, with specific medication selection based on cardiac function status. 1

Initial Assessment and Stabilization

• Hemodynamic stability assessment:
  • If unstable (hypotension, altered mental status, acute heart failure, ongoing chest pain): Immediate electrical cardioversion 2
  • If stable: Proceed with pharmacological rate control

Pharmacological Rate Control

First-line Medications Based on Cardiac Function:

1. For patients with Heart Failure with Reduced Ejection Fraction (HFrEF):

   • Beta blockers are preferred first-line therapy 1
   • Options include:
     • Esmolol: 500 mcg/kg IV over 1 min, then 60-200 mcg/kg/min IV
     • Metoprolol: 2.5-5 mg IV bolus over 2 min

2. For patients with preserved ejection fraction (HFpEF):

   • Non-dihydropyridine calcium channel blockers or beta blockers 1
   • Options include:
     • Diltiazem: 0.25 mg/kg IV over 2 min, then 5-15 mg/h IV
     • Verapamil: 0.075-0.15 mg/kg IV over 2 min
     • Beta blockers (as above)

3. Additional options for refractory cases:

   • Digoxin: 0.25 mg IV each 2 h, up to 1.5 mg (effective for resting heart rate control, particularly in HFrEF) 1
   • Amiodarone: 150 mg IV over 10 min, then 0.5-1 mg/min IV (consider when other agents fail) 1

Target Heart Rate:

• 60-80 beats per minute at rest
• 90-115 beats per minute during moderate exercise 1

Evidence Considerations

• Recent meta-analysis shows metoprolol is associated with 26% lower risk of adverse events compared to diltiazem (10% vs 19% incidence) 3
• Despite traditional contraindication, diltiazem may be considered as a second-line option in HFrEF patients with AFib RVR when beta blockers are contraindicated or ineffective 4, 5
• Combination therapy (digoxin plus beta blocker or calcium channel blocker) may provide better rate control during both rest and exercise 1

Anticoagulation Management

• Anticoagulation should be continued for at least 4 weeks after cardioversion if AFib duration was ≥48 hours or unknown 1
• Long-term anticoagulation based on CHA₂DS₂-VASc score:
  • Score ≥2 in men or ≥3 in women: Indefinite anticoagulation recommended 1
  • Warfarin (target INR 2.0-3.0) is recommended if contraindications to DOACs exist 1, 6
  • DOACs (e.g., apixaban) are preferred over warfarin in patients with CKD G1-G4 1

Common Pitfalls to Avoid

1. Inappropriate medication selection:

   • Avoid calcium channel blockers as first-line in HFrEF (use beta blockers instead)
   • Avoid verapamil in HFrEF patients (diltiazem may be considered as second-line) 4

2. Inadequate monitoring:

   • Failure to assess heart rate during both rest and exercise
   • Neglecting to monitor for hypotension after rate control medication administration 7

3. Inadequate anticoagulation:

   • Ensure appropriate anticoagulation for at least 4 weeks post-conversion regardless of CHA₂DS₂-VASc score 1

4. Electrolyte imbalances:

   • Monitor and correct potassium and magnesium levels, particularly in patients with CKD 1

Follow-up Recommendations

• Cardiology follow-up within 1-2 weeks after discharge
• Regular monitoring of renal function and echocardiogram to reassess cardiac function 1
• Reassessment of rhythm, rate control, and anticoagulation status