Summary of the ED Medications Used to Manage Atrial Fibrillation

Highlight point: Urgent cardioversion should be undertaken for any patient with…

1. Active ischemia (symptomatic or ECG-evidence)2. Evidence of organ hypoperfusion3. Severe manifestations of heart failure4. Presence of a pre-excitation syndrome

Initial efforts should be directed at identifying and treating potential causative factors prior to immediate cardioversion

RATE CONTROL Indication: AF/flutter with rate>110bpm Beta Blockers:

o Have modest protection against recurrence1

o Best in elderly patients but could be used for any ageo Recommended: metoprolol XL 25mg QD

Calcium Channel Blockers:o May protect against AF-induced electrical remodeling2

o Do not prevent recurrence of AF3

o Best in younger patients, not ideal for older patientso Recommended: verapamil 80mg TID or cardizem 120mg QD

Bolus to control, only drip if you’re going to admit Alternatively, infuse Diltiazem 2.5 mg/min to max 50 mg11

If pt is unstable, give in 5 mg aliquots every few minutesRHYTHM CONTROL

Indications: Restoring sinus rhythm for clinically unstable pts or those with new onset AF between 24-48h and CHADS2

Amiodaroneo Associated with greatest likelihood of maintaining sinus rhythm4

150mg over 10mino Associated with highest risk of long-term complications5

o Ideal chemical agent for CV in hypotensive patientso Highest success rate of cardioversion but associate with most side

effects (confirmed in Canadian Trial of A.Fib, AFFIRM, and SAFE-T trials)

Ibutilideo Drug of choice (AHA/ACC) for chemical cardioversion of AF9

1mg over 10min (may repeat)o Associated with increased risk of Torsades

Recommended to be given along with 2g MagSulfate to prevent

o Must observe for 4h after administration Flecainide

o Excellent alternative choice for most patients (AHA/ACC guidelines) 300mg PO x1

o Associated with increased risk of arrhythmia Recommended to be given along with metoprolol to prevent

o Might be more efficacious than amiodarone10

OTHER DRUGS Digoxin

o To be used only for inotropic support in CHF patients with symptomatic hypotension and AF6

o May be considered adjunctively pts with RVR refractory to standard therapies

More efficacious when used in combination with CCB than beta-B7

ACE-inhibitor/ARBo May reduce rate of recurrence of AF8

o First line agent to be considered on converted (spontaneous or iatrogenic) patients with hypertension

Magnesiumo 2-4g over 10min monotherapy might be more efficacious than

amiodarone12 and cardizem13

o Won’t hurt…might help, but beware that boluses can cause hypotension

o If they convert and need admission, continue to drip at 1-2mg/h for maintenance

REFERENCES:1. Kuhlkamp et al. Use of metoprolol CR/XL to maintain sinus rhythm after

conversion from persistent atrial fibrillation. J Am Coll Cardiol. 20002. Tieleman et al. Verapamil reduces tachycardia-related electrical remodeling

of the atria. Circulation 19973. Fuster et al. ACC/AHA/ESC 2006 Guidelines for the Management of Patients

with Atrial Fibrillation. J Am Coll Cardiol 2006.4. McNamara et al. Management of atrial fibrillation. Ann Int Med 20035. Lafluente et al. Antiarrhythmic drugs for maintaining sinus rhythm after

cardioversion of atrial fibrillation. Ann Int Med 20066. European Heart Rhythm Association. Guidelines for the management of atrial

fibrillation. Eur Heart J 20107. Segal et al. The evidence for the drugs used in ventricular rate control. J Fam

Prac 20008. Tardif et al. Perondipril reduces the incidence of AF after cardioversion. Eur

Heart J 20079. NEJM 340:24 June 1999 JB17

10. Emerg Med J 2004; 21:19911. Resuscitation 52:167, 200212. Clin Card 12:2, 1989, J Am Coll Card 7:6, 198613. Internat J Cardiol 2001;79 287-29114. Ann Emerg Med 2005;45(4):347