Adenosine is used to terminate atrioventricular node dependent arrhythmias like AV nodal reentrant tachycardia and atrioventricular reentrant tachycardia. It is also useful in the treatment of other forms of tachycardias sometimes. Use of adenosine in tachycardias could be for diagnosis of the mechanism as well. Adenosine can induce a PR jump on surface ECG in those with AVNRT which can be used to differentiate AVNRT from AVRT with concealed accessory pathway. In those with concealed accessory pathway, pre-excitation will not be manifest in ECG as there is no antegrade conduction in that pathway in sinus rhythm. It takes part in the retrograde limb of re-entry in AVRT.
