III. Contraindications: Conditions that if present may trump the decision to anticoagulate

  1. Valvular heart disease
  2. Prior peripheral embolism
  3. Intracardiac thrombus
  4. Hyperthyroidism

IV. Criteria: Mnemonic = CHADS

  1. Congestive Heart Failure (1 point)
    1. Relative Risk of Stroke or TIA: 1.4
  2. Hypertension (1 point)
    1. Relative Risk of Stroke or TIA: 1.6
  3. Age over 75 years (1 point)
    1. Relative Risk of Stroke or TIA: 1.4
  4. Diabetes Mellitus (1 point)
    1. Relative Risk of Stroke or TIA: 1.7
  5. Stroke or TIA history (2 points)
    1. Mitral Stenosis or prosthetic Heart Valve carry similar risk and also indicate Warfarin
    2. Relative Risk of Stroke or TIA: 2.5

V. Disadvantages

  1. Does not account for atrial enlargement (higher risk of CVA)
  2. CHADS2-VASc Score is preferred over CHADS2 due to its greater efficacy

VI. Interpretation

  1. CHADS Score >2 (CVA risk >5% per year): Warfarin with goal INR 2.0 to 3.0
  2. CHADS Score 1 (CVA risk >4% per year): Warfarin or Aspirin
  3. CHADS Score 0: Aspirin 81 to 325 mg daily

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Calculation (SoapNote.org)

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
Czech Fibrilace ouška, Fibrilace síní, fibrilace síní, síňová fibrilace, FiS
Italian Fibrillazione auricolare, Fibrillazione atriale
Polish Migotanie przedsionków
Hungarian AFib, Fibrillatio atrialis, Pitvarfibrillatio
Norwegian Forkammerflimmer, Hjerteflimmer, Artrieflimmer