Adenosine and its cardiovascular effects.

Adenosine is a new antiarrhythmic agent recently released with the permission of the Food and Drug Administration. It is an endogenously occurring nucleoside indicated for use in the diagnosis and treatment of supraventricular tachycardia. Its greatest utility is in patients with AV nodal reentry. Its antiarrhythmic action is mediated at the cellular level through the potassium channel, causing hyperpolarization of the myocyte membrane potential. In addition to its current indication as an antiarrhythmic agent, adenosine is now being used under an investigational protocol for pharmacologic stress testing. It can be given in conjunction with thallium or used in echocardiography as an imaging tool for patients who can not be adequately exercised. Adenosine's side effect profile is relatively benign and the agent's extremely short half-life makes most adverse reactions clinically insignificant. In this report we attempt to highlight this agent's clinical utility and discuss its future in the cardiovascular pharmacopeia.