Management of sudden cardiac death risk in the very early postmyocardial infarction period

PURPOSE OF REVIEW: The purpose of this review is to summarize the numerous recent studies assessing the strategies to manage the increased risk of sudden cardiac death (SCD) early after a myocardial infarction (MI). RECENT FINDINGS: Early after a MI, the risk of SCD is high. Several trials have been completed in attempt to identify and treat patients at increased risk for SCD early post-MI. These trials have evaluated QT interval, cardiac autonomic modulation, signal-averaged ECG, microvolt T-wave alternans, electrophysiology testing and early measurement of the left-ventricular ejection fraction (LVEF). Although some of these parameters were associated with increased total mortality, no parameter provided adequate predictive accuracy of increased risk for SCD that could guide use of an implantable cardiac defibrillator (ICD). SUMMARY: Other than LVEF measured more than 40 days post-MI (consistent with current ICD guidelines), there is no noninvasive or invasive test that reliably predicts the risk for SCD or that can guide empiric ICD implantation soon after a MI. In the early post-MI period, therefore, the goal is to maximize medical therapy and revascularization. The LVEF should then be measured no sooner than 40 days post-MI and, if the LVEF is 35% or less, the patient should be considered for ICD implantation.