Atrial Fibrillation and Flutter

Atrial Fibrillation & Flutter - Benjamin Palmer


  • AF: 12-lead EKG with absence of p-waves and irregularly irregular QRS complexes
  • Flutter: typically sawtooth atrial activity with regular or regularly irregular QRS complexe
    • Look for “sawtooth” waves in inferior leads and V1; ventricular rate of ~150 or ~100
  • 3 classifications:
    • Paroxysmal (self-terminating within 7 days)
    • Persistent (not self-terminating, >7 days)
    • Permanent (normal rhythm cannot be restored)
  • Rapid ventricular response (RVR) is HR > 100 (ie AFib/Flutter w/ tachycardia)
    • RVR is the equivalent to sinus tachycardia in a patient with Afib
  • AF/RVR is far more often a consequence of hypotension than the cause of it
  • Avoid using antiarrhythmics (including amiodarone) in any pt you wouldn’t electrically cardiovert without TEE (e.g. not on chronic anticoagulation, unknown duration of AFib, possibility of prior asymptomatic episodes of AFib)


  • Causes: Mnemonic “H PIRATES”  
    • Hypertension
    • Pneumonia, Pericarditis
    • Post-op
    • Ischemia (rare)
    • Rheumatic Valve
    • Atrial Myxoma, Accessory Pathway
    • Thyrotoxicosis
    • Ethanol, Excess Volume
    • Sick sinus, sepsis




  • Always work to address the underlying cause (infection, volume overload etc)
  • Rate control is rarely an emergency unless the patient is hemodynamically unstable 
  • If acute rate control is NOT needed (i.e patient is hemodynamically stable), opt for PO meds
  • Treatment goals:
    • Rate control, Goal HR < 110
    • Anticoagulation
    • Rhythm Control (if indicated)
  • Rate control:
    • β-blockers (Metoprolol), calcium channel blockers (Diltiazem), Digoxin, Amiodarone
        • Before administering any nodal blocking agents be wary of WPW/pre-excitation
        • AV-node blocking in this setting can accelerate A-V conduction and VT/VF
        • Would use procainamide in those situations
  • HFrEF: low dose PO metoprolol provided pt is warm and well :perfused
      • Avoid CCB
      • Consider discussion with Cardiology for Digoxin or Amiodarone
  • If acute rate control needed, consider IV metoprolol 5mg x1 or IV diltiazem 15-20mg x1, must follow with maintenance therapy (See acute tachyarrhythmia section above)
  • Anticoagulation (AC):
    • If new onset a-fib and cardioversion is anticipated, begin AC as soon as possible, Lovenox > heparin drip initially, DOAC would also be acceptable
    • If new onset a-fib but no immediate plans for cardioversion, AC should be considered based off of CHA2DS2-VASc
        • AC in this setting is not an emergency
    • If arrhythmia persists >48 hours, AC should be initiated if indicated
    • If known a-fib continue his or her AC while inpatient
    • If procedures/surgery is anticipated, bridging AC w/ heparin or LMWH should be decided on a case-by-case basis, likely not indicated with low stroke risk
  • Rhythm Control:
    • New onset a-fib (first time diagnosis): most pts will be a candidate for trial of electrical cardioversion
        • If onset clearly within 48 hours, can proceed without TEE
        • If onset >48 hours, will need TEE to rule out LAA thrombus
        • If cardioversion is anticipated or performed, pts need AC for at least one month
    • If typical flutter, consider EP consult as ablation can be quickly and safely performed
    • If hemodynamically unstable, HFrEF, or highly symptomatic a-fib, should be considered for rhythm control strategies (options include class 1c agents (Flecainide) and class III agents (amiodarone, sotalol, dofetilide)​​​​​​​


  • Rate control typically achieved with beta blocker therapy, metoprolol is most frequently used and can be converted to once daily dosing with metoprolol succinate
  • AC pending CHA2DS2-VASc scoring; DOACs are typically the agents of choice 
    • Warfarin indicated in valvular afib (AF 2/2 mitral stenosis)
  • Rhythm control is a complex decision, consider EP referral 
    • If highly symptomatic or HFrEF, consider ablation vs pharmacologic rhythm control
  • Serial monitoring for risks/benefits of AC and tachycardia induced cardiomyopathy