Methodology for clinical trials with antiarrhythmic drugs to prevent XXXX : US experience.

@entity1164 @entity1 @entity712 @entity1165 @entity1167 @entity583 @entity943 @entity204 @entity1002
@entity1164 is a massive public health problem that claims almost a half million lives a year in the United States. Several high-risk groups have been identified: survivors of @entity1167 ; @entity1 with recurrent sustained @entity1165 ; survivors of @entity583 ( @entity583 ) who have more than 10 ventricular premature depolarizations (VPD) per hour or repetitive VPD; and @entity1 with class III or IV @entity712 ( @entity712 ) and unsustained @entity1165 . The effects of open label drug treatment have been tested in survivors of @entity1167 or sustained @entity1165 using either electrophysiologic studies or 24-hour ECG recordings and exercise testing. @entity1 classified as drug responders using these methods have a lower mortality rate during follow-up than do those classified as nonresponders. This result is difficult to interpret. The test procedures may be identifying effective drugs, or alternatively, drug testing may identify high- and low-risk groups even though the drugs have no effect on survival. Recently, study designs have been proposed for conducting controlled trials in @entity1 with malignant @entity943 . @entity943 after @entity583 have been the subject of intensive study for the past 20 years. About 20% of these @entity1 have @entity943 between 6 and 90 days after @entity583 . The presence of @entity943 after @entity583 increases the risk of dying two- to fourfold. @entity943 predict @entity204 independently of @entity1002 . However, it has not been demonstrated that treatment of @entity943 after @entity583 significantly decreases mortality. The goals of the @entity943 Pilot Study (CAPS) were: to find a therapeutic strategy that could significantly suppress @entity943 with an acceptable adverse effect rate; to determine efficient methods for case finding; to identify efficient methods for evaluating the efficacy of antiarrhythmic drug therapy; to demonstrate the feasibility of recruiting @entity1 and maintaining treatment over a 1-year period; and to evaluate the feasibility and usefulness of behavioral studies. The study enrolled 502 @entity1 , randomizing approximately 100 @entity1 each into one of five treatment limbs: one group treated with placebo, and four treated with antiarrhythmic drugs (two with class IC and two with class IA action). Dose adjustment was permitted; @entity1 who failed to satisfy the criteria for drug efficacy were permitted to cross over to a second drug ( @entity1 on class IC agents crossed over to class IA agents and vice versa).(ABSTRACT TRUNCATED AT 400 WORDS)
