FDA APPROVAL OF WIDER USE
OF IMPLANTABLE DEFIBRILLATOR

The implantable defibrillator was previously approved for use in patients who are at high risk of sudden death due to ventricular fibrillation and/or ventricular tachyarrhythmias and who have experienced one of the following situations: survival of at least one episode of cardiac arrest (manifested by a loss of consciousness) due to a ventricular tachyarrhythmia; recurrent, poorly tolerated sustained ventricular tachycardia (VT) that remains inducible or occurs spontaneously despite the most efficacious antiarrhythmic drug therapy that the patient can tolerate.

A new clinical study in this high risk population demonstrated that the implanted defibrillator is significantly better than drugs in reducing sudden cardiac deaths. A multicenter study in the United States and Europe of 196 heart attack patients at high risk for sudden death due to ventricular arrhythmias was conducted over 5 years. Patients included the study had a history of prior myocardial infarction, left ventricular ejection fraction of less than 35%, and a documented episode of nonsustained VT. On electrophysiologic testing these patients had an inducible ventricular tachyarrhythmia which was not suppressible with intravenous procainamide or an equivalent antiarrhythmic. Of the patients, 95 were implanted with defibrillators, and 101 were treated with medication. The group treated with the implanted defibrillators had 54% fewer deaths than those treated with drugs. Study sponsors stopped the study early because of the significance of the results in the test population.