[Adenosine triphosphate and supraventricular tachycardia].

UNLABELLED: Intravenously administered adenosine triphosphate (ATP) converts some supraventricular tachycardias to a sinus rhythm. Temporary atrioventricular block can help with the differentiation of different forms of supraventricular tachycardia.

METHOD: Twenty-one patients with different forms of supraventricular tachycardia were subjected to electrophysiological examination for diagnostic or therapeutic (ablation) purposes. During tachycardia (after 5 minutes duration) ATP Spofa was administered by the i.v. route within 3 s into the cubital vein--0.3 mg per 1 kg body weight.

RESULTS

One patient had two forms of supraventricular tachycardia. In the first group with auricular fibrillation (AF, n = 10), with auricular flutter (AFL, n = 5) and with automatic auricular tachycardia (AAT, n = 1) tachycardia was not eliminated by intravenously administered ATP. In the second group the authors were always able to eliminate paroxysmal supraventricular tachycardia, AV nodal reciprocal (AVNRT, n = 4) and atrioventricular reciprocal tachycardia (AVRT, n = 2) by intravenously administered ATP.

CONCLUSIONS

1. The authors conclude that ATP exerts an antiarrhythmic effect by blocking the reentry circuit in the AV node, i.e. it converts reentry supraventricular tachycardias (AVNRT and AVRT) to a sinus rhythm after reciprocal atrial activity. 2. The effect on atria can be proarythmogenic. 3. The authors did not confirm the effect on abnormal automaticity.