Design of Korean Noninvasive Risk Evaluation Study for Sudden Cardiac Death from Infarction or Heart Failure: Myocardial infarction study of K-REDEFINE registry

BACKGROUND AND OBJECTIVES: Despite significant advances in the treatment of acute myocardial infarction (MI), the prevention of sudden cardiac death (SCD), the most common mode of death in patients with MI, remains challenging. Furthermore, previous Korean MI registries did not address the issue of post-MI SCD. Additional risk stratifiers of post-MI SCD are still required to compensate for the limitation of using left ventricular ejection fraction to predict lethal arrhythmic events. SUBJECTS AND METHODS: We designed the first Korean prospective nationwide multicenter registry primarily focused on SCD; the Korean noninvasive Risk Evaluation study for sudden cardiac DEath From INfarction or heart failurE (K-REDEFINE). The registry consists of 2 groups of patients presenting with (1) acute MI or (2) acute heart failure (HF) at 25 tertiary referral cardiovascular centers. The primary endpoint of the MI group study of K-REDEFINE registry is the incidence and risk factors of post-MI SCD. In particular, the association between the risk of SCD and non-invasive Holter-based electrocardiogram (ECG) variables will be evaluated, such as T-wave alternans (marker of repolarization heterogeneity) and heart rate turbulence/variability (a marker of autonomic function). Other secondary study outcomes include atrioventricular arrhythmias, HF-related admission, repeated myocardial ischemic events, stroke, and overall deaths. CONCLUSION AND PERSPECTIVE: The K-REDEFINE registry will provide new prospects for the better management of MI patients with high risk of SCD by clarifying the burden and predictors of SCD and the clinical utility of various non-invasive ambulatory ECG-based variables in risk stratification for SCD in this patient population.

Design of Korean Noninvasive Risk Evaluation Study for Sudden Cardiac Death from Infarction or Heart Failure: Heart failure study of K-REDEFINE registry

BACKGROUND AND OBJECTIVES: Sudden cardiac death (SCD) is one of the most common causes of death in patients with heart failure (HF). However, there are no available data on SCD in previous Korean HF registries. Additionally, although widely used, the utility of left ventricular (LV) ejection fraction (EF) in risk stratification for SCD is limited. SUBJECTS AND METHODS: The Korean non-invasive Risk Evaluation study for sudden cardiac DEath From INfarction or heart failurE (KREDEFINE) is the first Korean prospective, nationwide multicenter registry, primarily focused on SCD. The registry consists of 2 groups of patients presenting with (1) acute HF or (2) acute myocardial infarction (MI) at 25 tertiary referral cardiovascular centers. Using the HF-group data of the K-REDEFINE registry, the incidence and risk factors of SCD in patients with HF will be assessed. In particular, the efficacy of Holter-based ECG variables, such as T-wave alternans (marker of repolarization heterogeneity) and heart rate turbulence/ variability (maker of autonomic function), in risk stratification for SCD will be evaluated. Other cardiovascular outcomes will also be analyzed, including atrioventricular arrhythmias, HF-related admission, stroke, and overall deaths. CONCLUSION AND PERSPECTIVE: The K-REDEFINE registry will pave the way for better management of patients with HF at high risk of SCD by elucidating the burden and risk factors of SCD and the clinical utility of various non-invasive ambulatory ECG-based parameters in risk stratification for SCD in this patient population.