[Therapeutic efficacy and diagnostic potential of adenosine in infants and children].

In an open study a total of 53 episodes of supraventricular reentrant tachycardia in 31 infants and children were treated with intravenous adenosine at two centers. Adenosine was given as a rapid intravenous bolus injection beginning with a dose of 0.1 mg/kg. If there was persistence of the dysrhythmia dosage was increased in 0.05 mg/kg-steps up to a maximum dose of 0.3 mg/kg if necessary. The median dose required for successful termination of the tachycardias was 0.15 mg/kg. In 26 patients with 48 episodes of regular narrow-QRS-complex tachycardia adenosine was used as the therapeutic agent of first choice. In all patients a shortlasting atrioventricular block occurred within seconds after the administration of adenosine. In 42 of 48 episodes of tachycardia (87%) the dysrhythmias were converted to a stable sinus rhythm. In six episodes (13%) recurrence of the tachycardia was observed immediately. In five children adenosine was used for diagnostic purpose: in three children with wide-QRS-complex tachycardia successful termination with adenosine proved the supraventricular origin of the dysrhythmia. In two children with suspected atrial flutter adenosine-induced atrioventricular block allowed identification of flutter waves in one patient while in the other patient no effect of adenosine was seen. Side-effects such as flush, chest-pain or abdominal pain were frequent but mild and only of a few seconds' duration. No influence of adenosine on blood pressure was noted. Only in one child with previously unknown sinus node dysfunction was a relevant electrophysiologic side effect seen: a prolonged sinus arrest with asystole of 12 seconds' duration occurred after adenosine administration.(ABSTRACT TRUNCATED AT 250 WORDS)