Natural history of potentially lethal ventricular arrhythmias in patients treated with long-term antiarrhythmic drug therapy

Myocardial ischemia is a compromised blood supply to the heart muscle that affects patients with coronary artery disease (CAD). Ischemic CAD patients sometimes experience episodes of arrhythmia abnormal heart beats. Life-threatening arrhythmias known as ventricular premature complexes (VPCs) are treated with antiarrhythmic drugs. It is not known whether this therapy actually reduces the risk of sudden death. Long-term antiarrhythmic therapy to prevent VPC was evaluated in 28 patients receiving the antiarrhythmic drug moricizine for one to 56 months. A transient reduction in drug efficacy was evident in 36 percent of the patients at follow-up. An increase in moricizine was needed in four (14 percent) of the patients. The drug ceased to be effective in another four patients (14 percent). Some patients experienced spontaneous resolution of arrhythmias, late arrhythmic events and delayed side effects. Although moricizine is a safe and effective drug for treating arrhythmias, its long-term ability to control arrhythmias is problematic. It is suggested that drug efficacy assessments be made every year. (Consumer Summary produced by Reliance Medical Information, Inc.)