Adenosine: a clinical experience and comparison with verapamil for the termination of supraventricular tachycardias.

The efficacy and side-effects of adenosine for treatment of supraventricular arrhythmias were compared to verapamil therapy in patients presenting to the emergency room. Clinical variables and the time interval from the initiation of treatment to the termination of the supraventricular tachycardia, as well as the time from the initial effective dose of medication to the termination of supraventricular tachycardia were compared for adenosine and verapamil. Adenosine was given to a total of 44 patients, 16 patients in the electrophysiology laboratory, and 28 patients in the emergency room for evaluation and termination of their tachycardia. In the electrophysiology laboratory, 7 patients had AV node reentry, 5 had Wolff-Parkinson-White syndrome, 2 of whom had atrial flutter and fibrillation but no bypass tract reentry, 1 had concealed bypass tract reentry, 1 had Lown-Ganong-Levine syndrome, 1 had intraatrial reentry, and 1 had an automatic atrial tachycardia. Twenty-five patients received adenosine in the emergency room and 3 patients in the hospital for 31 episodes of supraventricular arrhythmias. In the emergency room, 11 patients had supraventricular tachycardia due to AV node reentry, 3 had Wolff-Parkinson-White syndrome, 6 had atrial flutter or intra-atrial re-entry, 2 had ventricular tachycardia, and 3 had sinus tachycardia. In the hospital, 2 patients had atrial flutter and one had sinus tachycardia. The group of 14 patients with supraventricular tachycardia due to Wolff-Parkinson-White syndrome or AV node reentry presenting in the emergency room were compared in a retrospective manner to the patients treated with standard verapamil therapy with respect to time from initiation of therapy to termination of supraventricular tachycardia and time from effective dose of medication to the termination of supraventricular tachycardia, as well as side-effects. There was no significant difference between the two groups with respect to clinical variables. Adenosine converted 18 of 18 episodes of supraventricular tachycardia in 14 patients 24.6 +/- 9.6 seconds from the administration of the effective dose (0.104 +/- 0.024 mg/kg) and a mean of 4.4 +/- 2.0 minutes from the initiation of therapy. Verapamil converted 29 of 32 episodes of supraventricular tachycardia in 20 patients, 10.9 +/- 7 minutes from the administration of the effective dose, and a mean of 16.8 +/- 20 minutes from the initiation of therapy using a mean of 8.4 +/- 3.4 mg of IV verapamil.(ABSTRACT TRUNCATED AT 400 WORDS)