Friday, August 29, 2008 - 1:39AM EST

Introduction to Atrial Fibrillation

Classification of Atrial Fibrillation

The 2001 American College of Cardiology (ACC)/American Heart Association (AHA) guidelines for the management of patients with atrial fibrillation classifies atrial fibrillation into the following types:

  • Secondary Atrial Fibrillation - This type of atrial fibrillation occurs as a consequence of another underlying condition that is reversible if treated. Examples of underlying conditions that may lead to secondary atrial fibrillation include:

    • coronary artery disease
    • heart valve diseases (e.g., rheumatic heart disease)
    • hypertension (high blood pressure)
    • pericarditis (inflammation of the lining of the heart)
    • heart attack
    • cardiac surgery (e.g., coronary artery bypass graft surgery)
    • pulmonary embolism (blood clot to the lungs)
    • hyperthyroidism (overactive thyroid gland)
  • First Detected Atrial Fibrillation - The first time the patient's atrial fibrillation comes to the attention of a health care provider.

  • Recurrent Atrial Fibrillation - Refers to patients who have experienced a recurrence (2 or more episodes) of atrial fibrillation. Two types of recurrent atrial fibrillation are recognized:

    • Paroxysmal Atrial Fibrillation

      • intermittent episodes of atrial fibrillation lasting from minutes to hours
      • usually terminates spontaneously (self-limited)
    • Persistent Atrial Fibrillation

      • a sustained pattern of atrial fibrillation that does not terminate spontaneously
      • in some patients, recurrent episodes of paroxysmal atrial fibrillation can lead to persistent atrial fibrillation
  • Permanent Atrial Fibrillation - Atrial fibrillation that cannot be successfully reverted back to normal sinus rhythm with cardioversion (pharmacological or electrical).

  • Lone Atrial Fibrillation - Atrial fibrillation in a patient younger than 60 years of age who does not have any evidence of underlying heart disease. Patients with lone atrial fibrillation usually have a favorable prognosis and are unlikely to develop serious complications such as blood clots or stroke. Lone atrial fibrillation may be triggered by:

    • hyperthyroidism (overactive thyroid gland)
    • hypoglycemia (low blood sugar)
    • alcohol consumption (particularly "binge" drinking)
    • nicotine
    • caffeine