Administration of adenosine triphosphate or adenosine is an important clinical trial in diagnosis and treatment of arrhythmias. It may not only terminate the paroxysmal supraventricular tachycardia and the specific type of ventricular tachycardia, but also identify the mechanism of majority of arrhythmias. Otherwise, It is also a useful diagnostic test for sick sinus sydrome and a reliable methos to assess radiofrequency catheter ablation.