Erythromycin-induced QT prolongation and polymorphic ventricular tachycardia (torsades de pointes): case report and review.

Although uncommon, ventricular arrhythmias associated with erythromycin use have been reported previously, usually in the presence of heart disease and/or situations causing abnormal cardiac electrophysiology (such as bradycardia, hypokalemia, and the administration of other cardioactive drugs). We report a case of QT prolongation and polymorphic ventricular tachycardia (torsades de pointes) that was precipitated by the intravenous administration of erythromycin. In contrast to most other previously described patients, our patient did not demonstrate significant heart disease or other apparent factors contributing to the genesis of the arrhythmia.