Risk Stratification for Sudden Cardiac Death After Myocardial Infarction

Abstract

Sudden cardiac death (SCD) accounts for ∼50% of mortality after myocardial infarction (MI). Most SCDs result from ventricular tachyarrhythmias, and the tachycardias that precipitate cardiac arrest result from multiple mechanisms. As a result, it is highly unlikely that any single test will identify all patients at risk for SCD. Current guidelines for use of implantable cardioverter-defibrillators (ICDs) to prevent SCD are based primarily on measurement of left ventricular ejection fraction (LVEF). Although reduced LVEF is associated with increased total cardiac mortality after MI, the focus of current guidelines on LVEF omits ∼50% of patients who die suddenly. In addition, there is no evidence of a mechanistic link between reduced LVEF and arrhythmias. Thus, LVEF is neither sensitive nor specific as a tool for post-MI risk stratification. Newer tests to screen for predisposition to ventricular arrhythmias and SCD examine abnormalities of ventricular repolarization, autonomic nervous system function, and electrical heterogeneity. These tests, as well as older methods such as programmed stimulation, the signal-averaged electrocardiogram, and spontaneous ventricular ectopy, do not perform well in patients with LVEF ≤30%. Recent observational studies suggest, however, that these tests may have greater utility in patients with LVEF >30%. Because SCD results from multiple mechanisms, it is likely that combinations of risk factors will prove more precise for risk stratification. Prospective trials that evaluate the performance of risk stratification schema to determine ICD use are necessary for cost-effective reduction of the incidence of SCD after MI.

Impact of wearable cardioverter‐defibrillator compliance on outcomes in the VEST trial: As‐treated and per‐protocol analyses

“…We did not find any variables that demonstrated a statistically significant interaction with any of the outcome variables. However, there were trends toward improved survival with the WCD in patients with a cardiac arrest, pulmonary edema requiring intubation, or elevated Cr during their index MI, all of which are likely to portend higher mortality and arrhythmic death risk 13,14 …”

Comparison of Continuous ECG Monitoring by Wearable Patch Device and Conventional Telemonitoring Device

“…Current risk stratification models largely dependent to left ventricular ejection fraction lacks both sensitivity and specificity for prediction of sudden death. 1 Despite the fact that frequent ventricular ectopy or non-sustained VT (NSVT) were associated with post-MI mortality, 14 current guideline does not provide optimal indication or time period of 24-hour ECG monitoring in post-MI patients. 2 …”

“…For patients who have experienced stroke or myocardial infarction (MI), accurate diagnosis and treatment of arrhythmia is crucial for prevention of adverse outcome including additional embolic event or sudden cardiac death (SCD). 1 However, current guidelines do not provide appropriate indication, duration, or specific modality of electrocardiogram (ECG) monitoring for the diagnosis of arrhythmia in these patients. 2 …”

An Aurora Kinase B–Based Mouse System to Efficiently Identify and Analyze Proliferating Cardiomyocytes

“…Myocardial infarction (MI) is among the leading causes of morbidity and mortality worldwide, severely affecting human health (Waks and Buxton, 2018). MI leads to a rapid loss of a large number of cardiomyocytes, resulting in irreversible heart failure.…”