Hx
A common complication of CABG
Dx
Absence of P waves
Irregularly irregular rhythm
Classifications
Duration
Paroxysmal (<7 days duration)
Persistent (>7 days duration)
Permanent (>1 year)
Lone AF is AF (in any category) without structural heart disease and generally occurs in patients aged <60 years.
Complications
Embolic stroke (up to 5 events per 100 patient life-years). Risk is greater in presence of hx of previous stroke, heart failure, valvular disease, diabetes, or hypertension.
Ischemic heart disease
Thyrotoxicosis
Thrombus formation
Arterial embolism
Tx, if first episode
Identify and correct cause
Convert to sinus rhythm (ideally)
Admit to telemetry
Control rate with
1. Cardizem (IV bolus; if a-fib persists, start drip)
20 mg IV over 2 minutes, may repeat after 30 minutes. Once rate <=110 then convert to oral IR dosing q6h, keep on q6h to titrate then convert to extended release
Note: it is perfectly fine to treat with a non-dihydropyridine CCB (e.g. Diltiazem) even if recently/simultaneously treated with a betablocker (PO or IV)
and/or
2. Metoprolol
if 1 and 2 fail, use
Digoxin
Consult cardiology
Note
Cardioversion may be attempted, but not before stabilization with rate control.
Amiodarone can be used to convert to sinus rhythm. It has roughly the same efficacy as electrical cardioversion.
Sample loading dose regimen: Amiodarone 400mg po q12h x 8/7 then 200 mg po daily x 4/52. Remember to also anticoagulate
Tx
If hemodynamically unstable
Immediate synchronized DC cardioversion is indicated, with success rate of approximately 90% for recent-onset AF
Cardioversion is favored over pharmacologic cardioversion due to its higher success rate and reduced likelihood of inducing an arrhythmia
Stroke risk is decreased by
Anticoagulation (See CHADS2) PLUS
Rhythm control OR
Rate control
Rate control plus anticoagulation is preferred in most patients
If a patient is asymptomatic, without tachycardia, provide anticoagulation but not rate control
Rate control
Amiodarone (does both)
Digoxin
Calcium channel blockers
Beta blockers
Rhythm control
Amiodarone (does both)
Cardioversion
Quinidine
Tx (if WPW)
Cardioversion
OR
Procainamide
AVOID AV nodal blockers like beta-blockers, calcium channel blockers, digoxin, and adenosine because they can cause increased conductance through the accessory pathway
