Arrhythmia

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. There are four main types of arrhythmia: extra beats, supraventricular tachycardias, ventricular arrhythmias, and bradyarrhythmias. Extra beats include premature atrial contractions and premature ventricular contractions. Supraventricular tachycardias include atrial fibrillation, atrial flutter, and paroxysmal supraventricular tachycardia. Ventricular arrhythmias include ventricular fibrillation and ventricular tachycardia. Arrhythmias are due to problems with the electrical conduction system of the heart. A number of tests can help with diagnosis including an electrocardiogram (ECG) and Holter monitor. 

Model for Arrhythmia is useful in our understanding of the mechanisms of ventricular arrhythmia and of antiarrhythmic and proarrhythmic agents. Models can be induced by  aconitine with intravenous in jection,barium chloride and calcium choloridc, by chloroform and chloroform-adrenaline and cardiac glycoside etc..