Assessment of the association between the presence of fragmented QRS and the predicted risk score of sudden cardiac death at 5 years in patients with hypertrophic cardiomyopathy

Abstract

Objective:It has been shown that the presence of fragmented QRS (fQRS) is associated with poor prognosis in many cardiovascular diseases and in patients with hypertrophic cardiomyopathy (HCM). However, no study has shown an association with the absolute risk score of sudden cardiac death. The aim of this study was to determine the relationship between QRS and the predicted risk score of sudden cardiac death at 5 years (HCM Risk-SCD) in HCM patients.Methods:In total, 115 consecutive HCM patients were included in this prospective observational study. The patients were divided into two groups according to the presence [fQRS(+) group (n=65)] or absence [fQRS(–) group (n=50)] of fQRS on a 12-lead electrocardiogram (ECG).Results:The HCM Risk-SCD (%) HCM Risk-SCD (>6%) values and some echocardiographic parameters, including ventricular extrasystole, ventricular tachycardia, cardiopulmonary resuscitation, implantable cardioverter defibrillator implantation, appropriate shock, and heart failure at the time of admission, were significantly higher in the fQRS(+) group than in the fQRS(–) group (all p<0.05). Both univariate and multivariate analyses revealed fQRS and New York Heart Association (NYHA) class as independent predictors of HCM Risk-SCD. In a receiver operating characteristic (ROC) curve analysis, an HCM Risk-SCD value of >4 was identified as an effective cut-off point in fQRS for HCM. An HCM Risk-SCD value of >4 yielded a sensitivity of 77% and a specificity of 76%.Conclusion:fQRS is determined to be an independent high-risk indicator of HCM Risk-SCD. It seems to be associated with increased ventricular arrhythmias and some echocardiographic parameters.

Baseline fragmented QRS increases the risk of major arrhythmic events in hypertrophic cardiomyopathy: Systematic review and meta‐analysis

“…Fibrosis or tissue heterogeneity increases susceptibility to reentry and arrhythmias. The presence of fQRS is more common in patients with high-risk characteristics, such as family history of SCD, history of syncope, and HCM patients with a calculated HCM Risk-SCD score >6% (Ozyilmaz et al, 2017). The strength of the association of fQRS with MAE may depend on observed territory of distribution (Femenia et al, 2013;Kang et al, 2014).…”

“…Fragmented QRS (fQRS) is a marker of myocardial scar and identifies high-risk patients in various cardiac conditions, including acute coronary syndrome, cardiac sarcoidosis, Brugada syndrome, acquired long QT syndrome, or idiopathic dilated cardiomyopathy (Das, Khan, Jacob, Kumar, & Mahenthiran, 2006;Sha et al, 2011;Take & Morita, 2012). Recent studies suggest that fQRS is associated with increased major arrhythmic events in patients with HCM (Debonnaire et al, 2015;Femenia et al, 2013;Kang et al, 2014;Nomura et al, 2015;Ozyilmaz et al, 2017). However, no systematic review or meta-analysis of literature has been done to address the association in this group of patients.…”

Assessment of the relationship between the ambulatory electrocardiography-based micro T wave alternans and the predicted risk score of sudden cardiac death at five years in patients with hypertrophic cardiomyopathy

“…First, abnormal cell-to-cell conduction may contribute to the inhomogeneous action potential propagation and heterogeneous repolarization, which result in the alternans of T-wave in HCM. Second, fibrous tissue replacement of both RV and LV, an important characteristic of HCM, may delay cell-to-cell conduction and facilitate the development of re-entrant ventricular arrhythmias ( 19 ). Previous studies have shown that re-entry is the main mechanism responsible for ventricular arrhythmias causing sudden deaths ( 20 ).…”

Clinical and molecular characterization of seven patients with Danon disease

“…An fQRS on surface ECG reflects myocardial scarring and abnormal conduction (30). It may be used as an indirect marker to predict the presence of fibrosis (31) and has been associated with severe arrhythmic events and poor prognosis in HCM (32,33). The patients of the present study who presented with fQRS on surface ECG (57%) had an average age of ~11 years, which was much earlier than that reported in a previous review on patients with HCM (32).…”