Novel Strategy to Reduce Sudden-Death Risk in the Healing Phase After Myocardial Infarction

Abstract

For patients with reduced ejection fraction (EF), the risk of cardiac arrest is particularly high in the healing phase immediately after a myocardial infarction (MI). Estimates from recent clinical trials show an annualized sudden-death risk of 8% to 12% in the 3-month period after MI, even with optimal medical therapy including appropriate revascularization, β-adrenergic receptor blocker, aldosterone inhibitor, and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker therapy.1 Article p 19 The recently initiated Vest Prevention of Early Sudden Death Trial/Prediction of ICD Therapies Study (VEST/PREDICTS) illustrates the gravity of this situation (clinicaltrials.gov identifier NCT00628966). VEST/PREDICTS is randomizing acute MI patients with EF ≤35% to wear an external defibrillator, an apparatus that consists of a jacket containing electrodes to detect the cardiac rhythm, defibrillator patches with explosive gel packs that release conductive gel immediately before a shock is delivered, and an on-board computer to interpret and manage the rhythm.2 The device also contains 2 safety buttons that need to be pressed simultaneously to suppress a shock, in case the patient is still conscious when the tachycardia alarm goes off or in the event of a false alarm. Continued pressure on the buttons suppresses the shock, and release of the pressure allows the shock to proceed (assuming that the arrhythmia is still detected at that point). This suggests the unpleasant image of a patient squeezing the buttons with all available force in a panicked rush to the emergency room for less painful therapy, but, at the very least, the protection afforded by the vest should allow that patient to make it alive to the emergency room. Unfortunately, in 2008 this is the best we have to offer to reduce sudden-death mortality in the healing phase after MI. This is a sad state of affairs. In recent times, when we think of reducing …