WHAT CAN WE EXPECT FROM PROPHYLACTIC IMPLANTABLE DEFIBRILLATORS

Death due to ventricular tachyarrhythmia (VT) remains an important pub lic health problem; patients with prior myocardial infarction (MI) con stitute the largest identifiable population for prophylactic intervent ions. Targeting of progressively higher-risk subgroups of post-MI svrv ivors carries inevitable tradeoffs with respect to the global impact o f interventions on overall mortality. Therapy with aspirin, beta block ers, and angiotensin-converting enzyme (ACE) inhibitors comprise the b enchmark against which all additional interventions, including implant able defibrillators, must be measured. Initial enthusiasm for empiric amiodarone therapy has been tempered by the limited benefit demonstrat ed in recent randomized trials. Trials of other class III antiarrhythm ic drugs, including both d,l-sotalol and d-sotalol, have also failed t o demonstrate survival benefit. The Multicenter Automatic Defibrillato r Implantation Trial (MADIT) demonstrated significantly improved survi val associated with defibrillators in a small subgroup of post-MI surv ivors with a high short-term risk of death. The ultimate number and op timal criteria for selection of patients who may benefit from prophyla ctic defibrillator therapy after MI will undergo continued evolution a s new data from current and ongoing trials become available. (C) 1997 by Excerpta Medica, Inc.