Adenosine induced polymorphic ventricular tachycardia in adults without structural heart disease.

Adenosine has been reported to cause polymorphic VT in patients with congenital or acquired prolonged QT intervals and to cause pause dependent VT in a patient with a normal QT interval. There have been no previous reports of adenosine causing nonpause dependent polymorphic VT in patients without structural heart disease. We report two patients, with normal hearts and normal QT intervals, who developed nonsustained polymorphic VT that was not pause dependent. Adenosine induced polymorphic VT does not appear to be a marker of the long QT syndrome, but may be an uncommon yet not unexpected pharmacological response to drug administration.