II. Indications

  1. Chronic control
    1. Age over 65 years
    2. Coronary Artery Disease
    3. Contraindications to Antiarrhythmic medications
    4. Cardioversion unlikely to be effective (e.g. atrial enlargement)
  2. Acute episode
    1. Atrial Fibrillation with rapid ventricular rate

III. Precautions

  1. Beware agents which may cardiovert Atrial Fibrillation >48 hours
    1. Risk of embolic complications

IV. Exam: Target Heart Rate

  1. Heart Rate with Exercise: <110 bpm
  2. Heart Rate at rest: <80 bpm
    1. Heart Rates up to 110 at rest may be acceptable for asymptomatic patients

V. Preparations: First-Line Agents for acute rate control (rapid ventricular rate)

  1. Precautions
    1. Avoid these agents in WPW Syndrome or other accessory pathway (pre-excitation states)
    2. Atrial Flutter is more difficult to rate control than Atrial Fibrillation
      1. However Atrial Flutter responds better to cardioversion
  2. Background
    1. Acute agent choice is often based on the agent patient is already taking
      1. Consider Diltiazem IV if on a Calcium Channel Blocker
      2. Consider Metoprolol IV if on a Beta Blocker
    2. Diltiazem IV is used most commonly for acute rate control in U.S. emergency departments
    3. Diltiazem IV may be preferred from study data
      1. More rapid acting, more effective and with less risk of Hypotension than Metoprolol
      2. Fromm (2015) J Emerg Med 49(2):175-82 +PMID:25913166 [PubMed]
    4. Metoprolol IV is preferred if ejection fraction <35%
  3. Diltiazem
    1. Bolus: In 10-20 mg (or 0.35 mg/kg) increments up to 50 mg IV cummulative total bolus
    2. Next: 5-20 mg/hour IV infusion
    3. Avoid in WPW Syndrome or other accessory pathway or if ejection fraction <35%
    4. If Hypotension occurs, consider Calcium Gluconate (does not counter AV Block)
  4. Metoprolol
    1. Bolus: 5 mg IV every 5 minutes up to 3 doses (15 mg)
    2. Next: 25-50 mg orally
    3. Avoid in WPW Syndrome or other accessory pathway
  5. Disposition
    1. Do not use Diltiazem with Metoprolol (risk of AV Block)
    2. If already on a rate control agent (e.g. Metoprolol or Diltiazem) when presented with RVR
      1. Increase the oral dose of that agent after IV rate control achieved
      2. If at maximum dose, consider adding Digoxin 0.125 mg or Amiodarone (consult cardiology)
    3. If not on a rate control agent, consider Metoprolol first
      1. Oral Metoprolol appears more effective for chronic rate control than oral Diltiazem
      2. Contrast with IV forms, in which Diltiazem appears more effective in acute rate control

VI. Preparations: Second-Line Agents for acute rate control (rapid ventricular rate)

  1. Esmolol
    1. Bolus: 500 mcg/kg IV
    2. Next: 50-200 mcg/kg/min IV infusion
    3. Requires very close (1:1) monitoring
    4. Avoid in WPW Syndrome or other accessory pathway
  2. Magnesium
    1. Bolus: 2.5 g IV over 20 minutes
    2. Next: 2.5 g IV over 2 hours
    3. Slow or stop infusion for Hypotension or respiratory depression
  3. Procainamide
    1. Bolus: 20-30 mg/min IV until controlled rate
    2. Next: 2-6 mg/min IV up to 17 mg/kg
    3. Stop for Hypotension or QRS Widening >50%
  4. Amiodarone
    1. Bolus: 150 to 300 mg IV
    2. Next: 1 mg/min IV infusion
    3. Prepare for Hypotension
  5. Digoxin
    1. Bolus: 0.5 mg IV
    2. Next: 0.25 mg orally at 4 and 8 hours
    3. Avoid in WPW Syndrome or other accessory pathway

VII. Protocol: Rate Control if WPW Syndrome with preserved heart function

  1. General
    1. Risk of embolus if rhythm cardioverts
    2. Consider Atrial Fibrillation Anticoagulation
  2. Avoid Harmful agents
    1. Adenosine
    2. Beta Blocker
    3. Calcium Channel Blocker
    4. Digoxin
  3. Recommended agents (Use only 1 agent)
    1. Electrical Synchronized Cardioversion if unstable
    2. Class IA Agents
      1. Procainamide
    3. Class IC Agents
      1. Propafenone (Rythmol)
      2. Flecainide (Tambocor)
    4. Class III Agents
      1. Sotalol (Betapace)
  4. Mixed Evidence
    1. Amiodarone (Cordarone) may induce ventricular arrhythmias in WPW (per 2010 ACLS guidelines)

VIII. Protocol: Rate control if WPW with Ejection Fraction <40%

  1. General
    1. Risk of embolus if rhythm cardioverts
    2. Consider Atrial Fibrillation Anticoagulation
  2. Recommended agents
    1. Electrical Synchronized Cardioversion
    2. Amiodarone (Cordarone)

IX. Protocol: Rate control if Heart function preserved (No WPW)

  1. General
    1. Risk of embolus if rhythm cardioverts
    2. Consider Atrial Fibrillation Anticoagulation
  2. Recommended agents
    1. Beta Blockers (preferred)
      1. Metoprolol (Lopressor) - preferred
      2. Propranolol (Inderal)
      3. Esmolol (Brevibloc)
    2. Calcium Channel Blocker
      1. Verapamil (Calan)
      2. Diltiazem (Cardizem) - preferred
        1. See Diltiazem for dosing protocol
  3. Second line agents
    1. Digoxin
      1. Effect on Heart Rate is delayed 3 hours (contrast with 5 minutes for Diltiazem)
    2. Amiodarone
      1. Not as effective as Diltiazem or Magnesium for rate control in most cases
      2. Used in critically ill patients with Atrial Fibrillation
      3. Clemo (1998) Am J Cardiol 81(5): 594-8 [PubMed]
    3. Magnesium Sulfate
      1. Effective adjunctive management of ventricular response rate control
      2. Slows AV nodal conduction and decreases Heart Rate
      3. Davey (2005) Ann Emerg Med 45(4): 347-53 [PubMed]

X. Protocol: Rate control if Ejection Fraction <40% (No WPW)

  1. General
    1. Risk of embolus if rhythm cardioverts
    2. Consider Atrial Fibrillation Anticoagulation
  2. Recommended agents
    1. Diltiazem (Cardizem) - preferred
    2. Amiodarone
    3. Digoxin (Lanoxin)
      1. Avoid Digoxin for Atrial Fibrillation Rate Control outside of comorbid CHF
      2. Increased mortaility when used for Atrial Fibrillation Rate Control
      3. Whitbeck (2012) Eur Heart J 10.1093/eurheartj/ehs348
        1. http://eurheartj.oxfordjournals.org/content/early/2012/11/14/eurheartj.ehs348.full

XI. Management: Choosing longterm rate versus rhythm control

  1. Rate control has less drug-related adverse effects
  2. Rate control has equivalent efficacy to rhythm control
    1. Same survival benefit
    2. Same Cerebrovascular Accident risk
  3. Rhythm control may offer benefit in age <65 years
  4. Beta Blockers (e.g. Metoprolol) are typically most effective oral agents for rate control
    1. Contrast with Diltiazem IV, which is typically more effective than IV Beta Blockers
    2. Avoid non-selective Beta Blockers in acute CHF, COPD, Asthma
  5. References
    1. Wyse (2002) N Engl J Med 347:1825-33 [PubMed]

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Ontology: Atrial Fibrillation (C0004238)

Definition (CHV) rapid tremor and shake of upper chambers of the heart
Definition (CHV) rapid tremor and shake of upper chambers of the heart
Definition (CHV) rapid tremor and shake of upper chambers of the heart
Definition (CHV) rapid tremor and shake of upper chambers of the heart
Definition (CHV) rapid tremor and shake of upper chambers of the heart
Definition (CHV) rapid tremor and shake of upper chambers of the heart
Definition (MEDLINEPLUS)

An arrhythmia is a problem with the speed or rhythm of the heartbeat. Atrial fibrillation (AF) is the most common type of arrhythmia. The cause is a disorder in the heart's electrical system.

Often, people who have AF may not even feel symptoms. But you may feel

  • Palpitations -- an abnormal rapid heartbeat
  • Shortness of breath
  • Weakness or difficulty exercising
  • Chest pain
  • Dizziness or fainting
  • Fatigue
  • Confusion

AF can lead to an increased risk of stroke. In many patients, it can also cause chest pain, heart attack, or heart failure.

Doctors diagnose AF using family and medical history, a physical exam, and a test called an electrocardiogram (EKG), which looks at the electrical waves your heart makes. Treatments include medicines and procedures to restore normal rhythm.

NIH: National Heart, Lung, and Blood Institute

Definition (NCI_CTCAE) A disorder characterized by a dysrhythmia without discernible P waves and an irregular ventricular response due to multiple reentry circuits. The rhythm disturbance originates above the ventricles.
Definition (NCI_FDA) An arrhythmia in which minute areas of the atrial myocardium are in various uncoordinated stages of depolarization and repolarization; instead of intermittently contracting, the atria quiver continuously in a chaotic pattern, causing a totally irregular, often rapid ventricular rate.
Definition (NCI) A disorder characterized by an electrocardiographic finding of a supraventricular arrhythmia characterized by the replacement of consistent P waves by rapid oscillations or fibrillatory waves that vary in size, shape and timing and are accompanied by an irregular ventricular response. (CDISC)
Definition (CSP) disorder of cardiac rhythm characterized by rapid, irregular atrial impulses and ineffective atrial contractions.
Definition (MSH) Abnormal cardiac rhythm that is characterized by rapid, uncoordinated firing of electrical impulses in the upper chambers of the heart (HEART ATRIA). In such case, blood cannot be effectively pumped into the lower chambers of the heart (HEART VENTRICLES). It is caused by abnormal impulse generation.
Concepts Pathologic Function (T046)
MSH D001281
ICD9 427.31
SnomedCT 155364009, 266306001, 49436004
LNC LA17084-7
English Atrial Fibrillations, Auricular Fibrillation, Auricular Fibrillations, Fibrillations, Atrial, Fibrillations, Auricular, FIBRILLATION ATRIAL, AURICULAR FIBRILLATION, Auricular fibrillation, Fibrillation, Atrial, Fibrillation, Auricular, AF, atrial fibrillation, atrial fibrillation (diagnosis), Afib, AFib, Fibrillation atrial, Atrial Fibrillation [Disease/Finding], Fibrillation;atrial, afib, atrial fibrillation (AF), auricular fibrillations, atrial fibrillations, Familial Atrial Fibrillation, Fibrillation - atrial, ATRIAL FIBRILLATION, Atrial fibrillation, AF - Atrial fibrillation, Atrial fibrillation (disorder), atrium; fibrillation, auricular; fibrillation, fibrillation; atrial or auricular, Atrial Fibrillation, auricular fibrillation
French FIBRILLATION AURICULAIRE, FA, AFib, Fibrillation auriculaire, Fibrillation atriale
German VORHOFFLIMMERN, AF, Afib, Flimmern Vorhof, Herzohrflimmern, HERZVORHOFFLIMMERN, Vorhofflimmern, Aurikuläres Flimmern
Portuguese FIBRILACAO AURICULAR, FA, FIBRILHACAO AURICULAR, Fibrilhação auricular, Fibrilação Atrial, Fibrilação Auricular
Spanish FIBRILACION AURICULAR, FA, Fibrilación atrial, AURICULAR, FIBRILACION, fibrilación auricular (trastorno), fibrilación auricular, Fibrilación auricular, Fibrilación Atrial, Fibrilación Auricular
Dutch AFib, AF, atriumfibrillatie, hartoorfibrilleren, atrium; fibrilleren, auriculair; fibrilleren, fibrilleren; atrium of auriculair, atriale fibrillatie, Atriumfibrillatie, Boezemfibrillatie, Fibrillatie, atrium-, Fibrillatie, boezem-, Fibrilleren, boezem-
Swedish Förmaksflimmer
Japanese シンボウサイドウ, 心房細動, 心房性細動
Finnish Eteisvärinä
Russian USHKA PREDSERDIIA FIBRILLIATSIIA, PREDSERDII FIBRILLIATSIIA, ПРЕДСЕРДИЙ ФИБРИЛЛЯЦИЯ, УШКА ПРЕДСЕРДИЯ ФИБРИЛЛЯЦИЯ
Czech Fibrilace ouška, Fibrilace síní, fibrilace síní, síňová fibrilace, FiS
Italian Fibrillazione auricolare, Fibrillazione atriale
Croatian ATRIJ, FIBRILACIJA
Polish Migotanie przedsionków
Hungarian AFib, Fibrillatio atrialis, Pitvarfibrillatio
Norwegian Forkammerflimmer, Hjerteflimmer, Artrieflimmer