An arrhythmia is defined as the irregular rhythm of the heartbeat. The irregular rhythm could either be too slow or too fast (either less or more than the normal rate). Arrhythmias occur due to disturbances in the normal activation of the myocardium by cardiac impulses. Normal activation of the myocardium results in sinus rhythm, which is the normal rhythm of the heartbeat. Arrhythmias disturb the sinus rhythm of the heart. They can occur at any age, and their severity depends on associated cardiac structural changes.
The exact mechanism by which cardiac arrhythmias are caused is not fully understood and can vary according to the type of arrhythmias. Release of excess catecholamines from the body during stress, rapid changes in blood pressure, loss of oxygen flow to the cardiac tissue, inflammation or infection of the underlying cardiac muscle, anti-arrhythmic drugs, and increased demand for oxygen due to any physiological or pathological cause can cause cardiac arrhythmias.
Depending on the clinical features, site of involvement, and mechanisms, cardiac arrhythmias can be classified into various types.
Cardiac arrhythmias according to the heart rate are classified into:
Cardiac arrhythmias according to the mechanism are classified into:
Cardiac arrhythmias occur worldwide in people of every age and race. The most common type of these arrhythmias is atrial fibrillation. There is no gender preference, but certain arrhythmias such as atrial fibrillation (AF) occur more commonly in men than women. Risk factors for cardiac arrhythmias include:
Signs and symptoms of cardiac arrhythmias include:
Complications of cardiac arrhythmias include:
Differential diagnoses of cardiac arrhythmias include the distinction between different types of arrhythmias. Other related disorders in the differentials include:
The mainstay of treatment against cardiac arrhythmias is to restore normal cardiac rhythm, treat underlying functional or structural pathology and prevent coagulation of blood due to irregular rhythm of the heart.
The prognosis of cardiac arrhythmias depends upon the type of arrhythmia and associated structural changes in the heart. With advancing age, the morbidity and mortality associated with these also increase. The most common type of cardiac arrhythmia, atrial fibrillation (AF), is associated with the highest mortality (almost 2-fold greater risk of death). Its association with thromboembolic events can prove fatal for the patient.
Cardiac arrhythmias can be prevented by the prevention of risk factors.
Our clinical experts continually monitor the health and medical content posted on CURA4U, and we update our blogs and articles when new information becomes available. Last reviewed by Dr.Saad Zia on May 14, 2023.
What is an Arrhythmia? | American Heart Association
Inherited cardiac arrhythmias | Nature Reviews Disease Primers