Refractory postoperative torsades de pointes syndrome successfully treated with isoproterenol

P OLYMORPHIC VENTRICULAR tachycardia (PVT) is a variant of ventricular tachycardia, characterized by QRS complexes of changing amplitude, typically occurring at a rate of 200 to 250 depolarizations per minute. PVT in association with a prolonged QT interval comprise the torsades de pointes (TdP) syndrome.‘,* TdP may be caused by a variety of conditions (Table I), but is most commonly seen postoperatively in patients on antiarrhythmic medications, especially the class I-A agents such as quinidine and procainamide.3 Recognition of TdP syndrome is important because it may be resistant to. or worsened by, conventional treatment for the more common form of ventricular tachycardia. Unrecognized TdP that is inappropriately treated is potentially fatal.” A cast is reported of postoperative TdP, induced by procainamide and refractory to conventional therapy. that was successfully treated with isoproterenol.