ECG Risk Score Model to Predict SCD in HFrEF: Retrospective Review in a Tertiary Centre

Abstract

INTRODUCTION: Heart failure with reduced ejection fraction (HFrEF) patients need to be risk stratify as guidelines have shown that patients with left ventricularejection fraction (LVEF) <35% could be prevented from sudden cardiac death (SCD) by insertion of prophylactic implantable cardioverter-defibrillator (ICD). Thus we conducted a retrospective single tertiary centre study to evaluate the used of electrocardiogram (ECG) risk score model in identifying the individuals who at higher risk of SCD. MATERIALS AND METHODS: A total of 356 heart failure with reduced ejection fraction (HFrEF) patients treated at University Malaya Medical Centre between January 2017 and December 2021 were enrolled into this study. The patients’ demographics, types of heart failure, medications, and ECG parameters data were collected. The study outcomes were survivor or death in and the cause of death were subdivided into SCD or non-sudden cardiac death (non-SCD). RESULTS: A total of 156 study patients were survivor whereas another 120 had SCD and 70 had non-SCD. There were six ECG parameters that remained significant in the final model, namely the bundle branch block (BBB), abnormal P waves, QRS duration, QTc duration, TpTe interval and PR interval. The significant ECG parameters were combined into a risk score to enumerate prediction ability towards SCD. From our ECG risk score model, subject with ≥2 ECG abnormalities had more than 3-fold increased risk for SCD (HR 3.739, 95% CI 1.703-8.211, P 0.001) and the risk proportionately increased with increasing ECG abnormalities. CONCLUSION: Our findings suggested that the cumulative ECG risk score model was independently associated with SCD and particularly effective for LVEF <40% where risk stratification model remained scarce. So, we would like to propose for a prospective study to further evaluate our study outcome.