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Arrhythmia, also known as abnormal heart rhythm or irregular heartbeat, refers to any change in the normal sequence of electrical impulses produced by the heart. The abnormal heart rhythms can be slow or fast in rate, having extra beats, or have rhythm irregularity.
Age increases the probability of experiencing an arrhythmia. It can occur in people who do not have structural heart disease. Arrhythmias often occur during and after
heart attacks. Some types of arrhythmias, such as ventricular
fibrillation, are serious and potentially life-threatening. Arrhythmias can result in poor blood circulation to the vital organs of the body.
Slow heart rates (less than 60 beats per minute) are called
bradycardias. Fast heart rates (more than 100 beats per minute) are called tachycardia.
The most common type of heart rhythm problem is
atrial fibrillation (AF), which occurs when there is abnormal electrical activity within the upper chambers (atria) of the heart, resulting in the lower chambers (ventricles) to beat in a fast and irregular manner.
While some arrhythmias are harmless, it is important to rule out any serious arrhythmias (abnormal heart rhythms) or pre-existing heart problems.
These arrhythmic heart palpitations can have serious implications:
Supraventricular tachycardia (SVT)This is a prevalent arrhythmia in young adults This is experienced as a sudden burst of rapid heartbeats that begin and end abruptly, lasting for seconds or hours. SVT is usually not life threatening.
Atrial fibrillationThis fast and irregular palpitation occurs in the atria or upper chambers of the heart and could last a few minutes to an hour. Atrial fibrillation arrhythmias could become chronic and lead to stroke. It is seldom life-threatening, but the heart palpitations could indicate underlying coronary artery disease or heart valve disorders.
Ventricular tachycardia (VT)Ventricular tachycardia is a very rapid, but regular heartbeat of 100 beats or more a minute occurring in the lower chambers (ventricles) of the heart.
Sustained heart palpitations lasting more than 30 seconds are considered a medical emergency. They could indicate pre-existing heart diseases such as coronary artery disease or heart valve disorders.
Ventricular fibrillation (VF)If ventricular tachycardia is left untreated, it will lead to a life-threatening condition called ventricular fibrillation, characterised by very fast and very irregular heartbeats. It usually precedes a heart attack. You could lose consciousness within seconds and die within minutes.
The symptoms of an arrhythmia or abnormal heart rhythm include:
While arrhythmias may not always be prevented, having regular health screening or checkups with your doctor can help you note on any irregularities in heart rhythms.
Arrhythmias or abnormal heart rhythm occur when there is a short-circuit in the electrical impulses controlling your heartbeat. These electrical impulses are what will cause your heart to beat too rapidly, too slowly or irregularly.
There are different causes for cardiac arrhythmias, including intrinsic heart problems, endocrinological and metabolic causes. Some common triggers are exercise, stress, caffeine, alcohol, appetite suppressant and decongestants in cough and cold medicines.Other risk factors of arrhythmias include:
An abnormal heart rhythm or arrhythmia is diagnosed by a physical examination,
electrophysiologic studies. However, as arrhythmias are not always present, they may not occur during the physical examination.You may have already received diagnostic tests to confirm if you have an arrhythmia and its likely causes. Otherwise, your doctor may discuss some of these tests with you to see if you have AF:
The treatment of arrhythmias is targeted at its underlying cause if any, rate control and/or rhythm control, with focus to maintain adequate blood circulation to the rest of the body and to prevent complications of the arrhythmias.
In some cases, treating the underlying heart disease remove the arrhythmia. In general, arrhythmias can be treated with drugs,
electrical shock (cardioversion), implanting
automatic implantable defibrillators,
catheter ablation, or surgery.Other treatments for arrhythmias include:
Often arrhythmias can be managed by drug therapy alone. Anti-arrthymic drugs are commonly classified using Vaughan Williams cliassification. Response to drugs is usually measured by
holter monitor or
This clinic evaluates patients with cardiac arrhythmias, providing tertiary service for patients with complex cardiac arrhythmias that require further investigations and evaluations. It also provides follow up monitoring and care for patients with
defibrillators.If you suspect you may have arrhythmia or an abnormal heart rhythm, you may make an appointment with a cardiologist for further investigations and treatment.To make an appointment at NHCS, please visit here:Book an Appointment