Atrial Fibrillation (AFib)

Afib medical prevention

Atrial Fibrillation Symptoms and Signs

Symptoms of atrial fibrillation occur when the upper chambers of the heart (atria) beat in a disorganized fashion. Atrial fibrillation is a type of arrhythmia. Characteristic symptoms include:

  • shortness of breath,
  • palpitations, and
  • lightheadedness.

Other symptoms of atrial fibrillation are:

  • fatigue,
  • confusion, and
  • a reduced tolerance for exercise.

What is the normal function of the heart?

  • The heart has four chambers. (The upper two chambers are the atria, and the lower two chambers are the ventricles.)
    1. The right atrium (upper right)
    2. The left atrium (upper left)
    3. The right ventricle (lower right)
    4. The left ventricle (lower left)
  • Blood returning to the heart from the body contain low levels of oxygen and high levels of carbon dioxide. This blood flows into the right atrium and then down into the adjacent right ventricle.
  • After the right ventricle fills, contraction of the right atrium pumps additional blood into the right ventricle.
  • The right ventricle then contracts and pumps the blood to the lungs where the blood takes up oxygen and gives off carbon dioxide.
  • The blood then flows from the lungs to the left atrium, and then down into the adjacent left ventricle.
  • Contraction of the left atrium pumps additional blood into the left ventricle.
  • The left ventricle then contracts and pumps the blood to the rest of the body.
  • The heartbeat (pulse) that we feel is caused by the contraction of the ventricles.
  • The ventricles must deliver enough blood to the body for the body to function normally.
  • The amount of blood that is pumped depends on several factors. The most important factor is the rate of contraction of the heart (the heart rate).
  • As the heart rate increases, more blood is pumped.
  • The heart pumps more blood with each beat when the atria contract and fill the ventricles with additional blood just before the ventricles contract. Continue Reading
Reviewed on 5/27/2015
Atrial Fibrillation Pictures Slideshow: Visual Guidelines to Causes, Tests and Treatment


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