Categories of Arrhythmias
Arrhythmias are generally divided into two categories: ventricular and supraventricular. Ventricular arrhythmias occur in the lower chambers of the heart, called the ventricles. Supraventricular arrhythmias occur in the area above the ventricles, usually in the upper chambers of the heart, called the atria. The irregular beats can either be too slow (bradycardia) or too fast (tachycardia).
(Diagram of the electrical conduction system of the heart.)
Bradycardia
Bradycardia is a very slow heart rate of less than 60 beats per minute. It happens when the electrical impulse that signals the heart to contract is not formed in your heart's natural pacemaker, the sinoatrial node (SA node), or is not sent to the heart's lower chambers (the ventricles) through the proper channels.
Bradycardia most often affects elderly people, but it may affect even the very young. It may be caused by one of two sources: The central nervous system does not signal that the heart needs to pump more, or the SA node may be damaged. This damage might be related to heart disease, aging, inherited or congenital defects, or it might be caused by certain medicines—including those used to control arrhythmias and high blood pressure.
Symptoms of Arrhythmia
The most common symptoms of arrhythmia are:
* palpitations or rapid thumping in your chest
* feeling tired or light-headed
* loosing consciousness
* shortness of breath
* chest pain.
Symptoms of bradycardia:
* feeling tired
* short of breath
* dizziness
