Symptoms of arrhythmias include
Causes of arrhythmia
Electrical impulses that cause the heart to contract must follow a precise pathway for it to work properly. Any interruption to these impulses can result in arrhythmia. The human heart consists of four chambers - the chambers on each half of the heart form two adjoining pumps, with the atrium (upper chamber) and the ventricle (lower chamber).
When heartbeat occurs, the less muscular and smaller atria contract and fill the relaxed ventricles with blood. The contraction starts when a small group of cells in the right atrium (the sinus node) send an electrical impulse which causes the right and left atria to contract. The impulse then moves to the atrioventricular node (at the center of the heart) on the pathway between the atria and ventricles. From here the impulse leaves the atrioventricular node, travels through the ventricles, causing them to contract and pump blood - this blood pumps throughout the body.
For a person with a healthy heart the process works properly and he/she should have a heart rate of between 60 and 100 beats per minute when resting. The fitter you are the lower your resting heart rate. Olympic athletes, for example, will usually have a resting heart rate of less than 60 beats per minute because their hearts are very efficient.