LIFE-THREATENING ALTERATIONS IN HEART-RATE AFTER THE USE OF ADENOSINEIN ATRIAL-FLUTTER

Adenosine has become the preferred treatment for common types of supra ventricular tachycardia because it is extremely effective and rarely a ssociated with serious side effects. It has also been advocated as an intervention for diagnostic use to assess uncommon types of tachycardi a. Evidence is shown in this report that adenosine was associated with dangerous worsening of arrhythmia in patients with atrial flutter. In two patients, adenosine precipitated acceleration of ventricular resp onse, in one case necessitating emergent cardioversion. Both patients had atrial flutter with 2 to 1 atrioventricular block that evolved int o 1 to 1 atrioventricular conduction. In three other patients, adenosi ne was associated with prolonged bradyasystole and hypotension. In eac h of the five patients, adenosine was given in a standard fashion (6 o r 12 mg). In summary, adenosine should be recognized as a potentially dangerous intervention in patients with atrial flutter. If it is used for diagnostic purposes, resuscitative equipment should be readily ava ilable.