Tachycardia
greater than 100 beats per minute. The tachycardias include sinus tachycardia, paroxysmal atrial tachycardia ( PAT ) , and ventricular tachycardia.
Sinus tachycardia is due to rapid firing of a normal structure called the sinoatrial ( sinus ) node which is the natural pacemaker of the heart. Sinus tachycardia occurs in response to exercise, exertion, excitement, pain, fever, excessive thyroid hormone, low blood oxygen ( hypoxia ) , stimulant drugs ( such as caffeine and amphetamines ) , etc.
Paroxysmal atrial tachycardia ( PAT ) consists of bouts of rapid, regular heart beating originating in the atrium ( upper chamber of the heart ) . Often due to abnormalities in the AV node "relay station" that lead to rapid firing of electrical impulses from the atrium which bypass the AV node under certain conditions. These conditions include alcohol excess, stress, caffeine, overactive thyroid or excessive thyroid hormone intake, and certain drugs. PAT is an example of an arrhythmia where the abnormality is in the electrical system of the heart, while the heart muscle and valves may be normal.
Ventricular tachycardia is an abnormal heart rhythm that
is rapid, regular and originates from an area of the ventricle, the lower chamber of the heart. Ventricular tachycardias are most commonly associated
with heart attacks or scarring of the heart muscle from previous heart attacks and are life threatening.
Tachycardia in Wikipedia
Tachycardia refers to rapid beating of the heart. By convention it is defined as a heart rate greater than 100 beats per minute in adults. Tachycardia may be normal, such as in exercise and stress, or abnormal, such as in cardiac arrhythmias. However, depending on the mechanism of the tachycardia and the health status of the person, tachycardia may be harmful and require medical treatment. In ext ....View wikipedia
Related Pages on Tachycardia
Tachycardia
Tachycardia refers to rapid beating of the heart. By convention it is defined as a heart rate greater than 100 beats per minute in adults. Tachycardia may be normal, such as in ... 
Tachycardia - Wikipedia, the free encyclopedia
A supraventricular tachycardia (SVT) is a tachycardia or rapid rhythm of the heart in which the origin of the electrical signal is either the atria or the AV node.