Efficacy and Safety Evaluation of Azimilide Dihydrochloride in Patients With Implantable Cardioverter Defibrillators

Inclusion criteria: * Currently have an ICD implanted * Have had a documented episode of symptomatic arrhythmias that triggered a spontaneous ICD shock within 180 days of randomization. * If the ICD implant is recent, the patient must have had a documented episode of sustained arrhythmias or cardiac arrest within 42 days before implantation of the ICD Exclusion criteria: * have severe heart failure * have a current diagnosis of psychosis * use illicit drugs * abuse alcohol * if female, are currently breast feeding, or plan to become pregnant during the study * are currently taking antiarrhythmic drugs or other drugs that prolong the QTc interval (a measurement taken from the ECG) * creatinine \>2.5 mg/dL (221 mmol/L) * potassium \<4.0 mEq or \>5.5 mEq * have a neutrophil count (ANC) \< 100 mL (low count of a type of white blood cell) at time of randomization * have 2 or more consecutive QTc values \>440 msec