What´s Cardiac Arrhythmia?

ARRHYTHMIA

Description

Cardiac arrhythmia, also known as cardiac dysrhythmia or irregular heartbeat, is a group of conditions in which the heartbeat is irregular, too fast, or too slow. Arrhythmias are due to problems with the electrical conduction system of the heart. The most common forms of arrhythmia observed is either, tachycardia (A heartbeat that is too fast - above 100 beats per minute in adults) or bradycardia (A heartbeat that is too slow - below 60 beats per minute). While most types of arrhythmia are not serious, some predispose a person to complications such as stroke or heart failure. Others may result in cardiac arrest.

There are four main types of arrhythmia

1. Extra beats: Extra beats include premature atrial contractions

Supraventricular tachycardias: Supraventricular tachycardias include atrial fibrillation, atrial flutter, and paroxysmal supraventricular tachycardia. This is a type of tachycardia that originates from above the ventricles, such as the atria. It is sometimes known as paroxysmal atrial tachycardia (PAT). Several types of supraventricular tachycardia are known to exist.

3. Ventricular arrhythmias: It includes Ventricular Tachycardia, Ventricular Fibrillation and Premature Ventricular Contractions. In adults and children over 15, resting heart rate faster than 100 beats per minute is labelled tachycardia. Tachycardia may result in palpitation; however, tachycardia is not necessarily an arrhythmia. Increased heart rate is a normal response to physical exercise or emotional stress. This is mediated by the sympathetic nervous system on the sinus node and called sinus tachycardia.

4. Bradyarrhythmias: A slow rhythm (less than 60 beats/min), is labelled bradycardia. This may be caused by a slowed signal from the sinus node (sinus bradycardia), a pause in the normal activity of the sinus node (sinus arrest), or by blocking of the electrical impulse on its way from the atria to the ventricles (AV block or heart block). Heart block comes in varying degrees and severity. It may be caused by reversible poisoning of the AV node (with drugs that impair conduction) or by irreversible damage to the node. Bradycardias may also be present in the normally functioning heart of endurance athletes or other well-conditioned