Causes of AFib

Conditions that damage or strain the heart commonly cause atrial fibrillation. These include:
  • High blood pressure
  • Coronary artery disease
  • Heart attack
  • Heart valve disease
  • Congenital heart disease
  • Pulmonary embolism

Other possible causes include:

  • Other medical problems, such as heart failure, lung disease, pneumonia, or a high thyroid level
  • Heart surgery
  • Heavy alcohol use (having more than three drinks a day over many years as well as drinking large amounts at one time)
  • Use of stimulants including nicotine, medications such as decongestants and illegal drugs such as cocaine
  • Use of some prescription medications such as albuterol or theophylline

In at least 10 percent of AFib cases, no underlying heart disease is found. In these cases, AFib may be related to alcohol or excessive caffeine use, stress, certain drugs, electrolyte or metabolic imbalances, severe infections, or genetic factors. In some cases, no cause can be found.