Cardiac dysrhythmia

Cardiac dysrhythmia (also known as arrhythmia or irregular heartbeat) is a group of conditions in which the heartbeat is irregular, too fast, or too slow. A heart rate that is too fast – above 100 beats per minute in adults – is called tachycardia and a heart rate that is too slow – below 60 beats per minute – is called bradycardia. Many types of dysrhythmia have no symptoms. When symptoms are present, they may include palpitations or feeling a pause between heartbeats.

Types of Cardiac Dysrhythmia

There are many types of cardiac dysrhythmia. They are categorized by where they originate (atria or ventricles) and by the speed of heart rate they cause:

• Atrial fibrillation and atrial flutter are irregular heart rhythms that occur in the atria of the heart. These can lead to blood clots forming in the heart, which may circulate to other organs and lead to stroke.
• Ventricular fibrillation is a serious condition in which the heart's electrical activity becomes disordered. When this happens, the heart's lower (pumping) chambers contract in a rapid, unsynchronized way. The heart can't pump blood effectively, which can cause cardiac arrest.

Causes

Cardiac dysrhythmia can be caused by a variety of factors including heart disease, hypertension, diabetes, and thyroid disease. Lifestyle factors such as smoking, alcohol, and illicit drug use can also contribute to the development of dysrhythmia.

Diagnosis

Diagnosis of cardiac dysrhythmia is made by using an electrocardiogram (ECG), which records the electrical activity of the heart. Other tests may include a Holter monitor, which is a portable ECG device worn for a day or more to record the heart's activity as the person goes about their daily activities.

Treatment

Treatment of cardiac dysrhythmia depends on the type of dysrhythmia, the severity of symptoms, and the overall health of the individual. Treatment options may include medications, lifestyle changes, and in some cases, surgery or a procedure called catheter ablation.

See also

• Heart disease
• Electrocardiogram
• Atrial fibrillation
• Ventricular fibrillation