Successful treatment by overdrive pacing of recurrent quinidine syncope due to ventricular tachycardia.

A 54 year old patient who experienced recurrent ventricular tachycardia subsequent to quinidine administration for conversion of atrial fibrillation is described. Over a 10 hour period, 25 sustained episodes of ventricular tachycardia occurred for which electrical cardioversion was required in addition to numerous self-terminating paroxysms. Medical therapy with lidocaine, procainamide and propranolol was unsuccessful in controlling the arrhythmia. However, placement of a transvenous right ventricular pacemaker with overdrive pacing at a rate of 110 beats/min abrupty terminated all further ventricular ectopic activity during the period of quinidine elimination. Temporary overdrive pacing may be the treatment of choice for refractory, recurrent, ventricular tachycardia associated with quinidine therapy.