Long-term use of controlled-release disopyramide in patients with severe ventricular arrhythmias

Controlled-release (CR) disopyramide phosphate has been available for the past four years for the management of patients with ventricular arrhythmias. The advantages of this preparation over the earlier form have for most patients been striking. Improved patient compliance as regards dosing, ease in stabilizing blood levels of disopyramide, and effective antiarrhythmic control has been a significant factor in physician satisfaction with this preparation. Studies have demonstrated that effective blood levels are obtained with the 12-hour dosing schedule for controlled-release disopyramide phosphate in both normal volunteers and in patients with cardiac arrhythmias. Concern over the safety of disopyramide in patients with significant underlying heart disease, and especially in patients with a history of congestive heart failure, has been reported in a number of publications. No clinical observations are available in which patients with intractable ventricular arrhythmias have been managed with controlled-release disopyramide phosphate in addition to other appropriate therapy for their cardiac condition. Fifteen patients with significant left ventricular dysfunction were followed for an average of 20.6 months while receiving controlled-release disopyramide phosphate, and control of ventricular arrhythmias was achieved without worsening of left ventricular function.