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AFIB symptoms AND Signs

AFIB symptoms AND Signs

Afib Symptoms and Signs

What are the symptoms and signs of Afib?

Some patients with atrial fibrillation may have no symptoms. The commonest symptoms are palpitations (a fluttering sensation in the chest). Other commonly reported symptoms of atrial fibrillation are shortness of breath, tiredness, chest pain, fatigue, dizziness and even loss of consciousness (syncope). The reasons why some people with atrial fibrillation experience symptoms, while others do not, are not completely known. In many patients, the symptoms are related to a faster heart beat. However, some patients have symptoms, even if the heart rate is not fast. In some patients, if the heart beats too slowly during atrial fibrillation, this can also cause symptoms.

An irregular pulse (usually confirmed by listening to the heart with stethoscope) is the most common sign of atrial fibrillation at physical examination.

Table 1. 

Common signs and symptoms of atrial fibrillation

Irregular pulse


Shortness of breath

Feeling overtired or lacking energy

Dizziness or confusion

Light-headedness or fainting

Feelings of fear or anxiousness

Chest discomfort or chest pain

Syncope (loss of consciousness)

When should you seek urgent medical attention?

Some patients with atrial fibrillation can experience unpleasant symptoms which make them feel really unwell, particularly patients who have episodes of atrial fibrillation that come and go, known as paroxysmal atrial fibrillation. If you experience any or all of the above mentioned symptoms you should seek immediate medical attention at a hospital.

Is Afib dangerous?

Atrial fibrillation itself does not pose a direct and immediate risk of death and many patients live with the arrhythmia for decades. However, atrial fibrillation can lead to serious complications, such as:

  • Stroke
  • Heart failure


The most common and serious complication of atrial fibrillation is stroke. Stroke occurs in approximately 1 in 20 of patients with atrial fibrillation each year. People with atrial fibrillation are at 5-times increased risk of having a stroke compared to someone of the same age and sex who does not have atrial fibrillation.

In general, a stroke can happen in one of 2 ways: a blood vessel in the brain can either get blocked (cutting off blood flow; called ischemic stroke) or start bleeding (called hemorrhagic stroke). Strokes caused by blockage are more common than strokes caused by bleeding.

article1atrial fibrillation and stroke

Why does atrial fibrillation cause stroke?

A blood clot usually forms in the left atrial appendage due to decreased flow here. This happens because uncoordinated electrical activity in the atria stops them contracting properly, causing blood cells to stick together and increasing the risk of clots. Once formed, clots can break free in the blood stream and block arteries. If this occurs in brain arteries, a stroke is caused.

What are the symptoms and signs of stroke?

The amount and type of symptoms of stroke depend on what part of the brain is involved. The bigger the clot is and the larger the blocked artery is, the more devastating the consequences of the stroke can be. If very small clots are dislodged from the main clot in the heart, a mini-stroke (called a 'transient ischemic attack' or TIA) could occur and the symptoms resolve within a day.

The following tables show the most common signs and symptoms of stroke and you should seek immediate medical help if you experience any one (or more than one) of them, even if the symptoms are mild or go away after a few minutes:

Table 2.

Common signs and symptoms of stroke

Numbness or weakness in your face, arm, or leg, especially on one side

Asymmetry in the face or a droop on one side of the face

Confusion or trouble understanding other people

Unusual sensations on one side of the body

Trouble speaking (speech is slurred; cannot repeat a simple phrase)

Inability to swallow properly

Trouble seeing with one or both eyes (or sudden blindness)

Trouble walking or staying balanced or coordinated

Severe dizziness

Severe headache that comes on for no known reason

Table 3.

Spot a stroke: the “F.A.S.T.” acronym

Face drooping – Does one side of the face droop or is it numb? Can the patient smile?

Arm Weakness – Is one arm weak or numb? Can the person raise both arms? Does one arm drift downwards?

Speech Difficulty – Is their speech slurred? Is the patient able to speak, or is he or she hard to understand? Can the patient repeat a simple sentence, like “the sky is blue”?

Time to call the emergency medical services – If the patient shows any of these symptoms, even if the symptoms go away, call your country's emergency number and get him or her to hospital immediately.

Heart failure

Patients with long-standing atrial fibrillation are at risk of developing heart failure, whereby the heart is no longer capable of pumping a sufficient amount of blood to the organs and tissues. Although atrial fibrillation can lead to heart failure, patients who have heart failure for other reasons are more likely to develop atrial fibrillation. So in some situations it may be difficult to establish which of these two conditions occurred first if both are present. Not everyone who has atrial fibrillation will develop heart failure.