Cardiac arrhythmias are caused by a disruption or abnormality in the electrical impulses of the heart. The heart is less efficient at pumping blood when the beats are too fast, too slow or when the beats are irregular. Cardiac arrhythmias are common, and most are harmless, according to the American Heart Association. However, some arrhythmias can reduce a person's quality of life, and others can be life threatening.
Fibrillation
Fibrillation of the heart can originate in the upper heart chambers called the atria, or in the lower chambers, called the ventricles. This arrhythmia results in a quiver, rather than an effective heart beat.
Atrial fibrillation is a manageable condition but can result in stroke or heart failure, especially if untreated.
Fibrillation of the ventricles can quickly result in death, because the heart can't pump enough blood.
Bradycardia
This type of arrhythmia is when the heart beats too slowly, and is defined as an adult heart rate of less than 60 beats per minute, reports the National Heart Blood and Lung Institute. This condition can cause a decrease in blood flow to the brain, and result in fatigue, dizziness and fainting spells. Left untreated, bradycardia can lead to complications such as high blood pressure, and even heart failure.
Tachycardia
Tachycardia is when the heart beats too rapidly with a rate of over 100 beats per minute. This arrhythmia can begin in either the atria or the ventricles of the heart. Tachycardia can cause poor blood circulation. It results in the sensation of a racing heart, light headedness, dizziness and fainting. Tachycardia originating suddenly in the ventricles of the heart can be life threatening.
Premature Contractions
These rhythm disturbances can arise from either the atria or the ventricles, and are common in both normal children and adults. Premature contractions can feel as though the heart has skipped a beat, but an extra beat occurred early. Premature contractions are generally harmless, and resolve on their own. Usually, no particular cause is found for these abnormal rhythms.
Wolff-Parkinson-White Syndrome
Wolff-Parkinson-White syndrome is a condition that results from a faulty electrical connection in the heart. This condition occurs in about 4 out of 100,000 people. It can cause rapid heart rates, increasing the risk for sudden cardiac death.
