Used as an initial treatment for the termination of paroxysmal supraventricular tachycardia (PVST), including that associated with accessory bypass tracts, and is a drug of choice for terminating stable, narrow-complex supraventricular tachycardias (SVT). Also used as an adjunct to thallous chloride TI 201 myocardial perfusion scintigraphy (thallium stress test) in patients who are unable to exercise adequately, as well as an adjunct to vagal maneuvers and clinical assessment to establish a specific diagnosis of undefined, stable, narrow-complex SVT.
Adenosine slows conduction time through the AV node and can interrupt the reentry pathways through the AV node, resulting in the restoration of normal sinus rhythm in patients with paroxysmal supraventricular tachycardia (PSVT), including PSVT associated with Wolff-Parkinson-White Syndrome. This effect may be mediated through the drug's activation of cell-surface A<sub>1</sub> and A<sub>2</sub> adenosine receptors. Adenosine also inhibits the slow inward calcium current and activation of adenylate cyclase in smooth muscle cells, thereby causing relaxation of vascular smooth muscle. By increasing blood flow in normal coronary arteries with little or no increase in stenotic arteries (with little to no increase in stenotic arteries), adenosine produces a relative difference in thallous (thallium) chloride TI 201 uptake in myocardium supplied by normal verus stenotic coronary arteries.
Less than 10 secs