Abstract 11440: Fragmented QRS as a Novel Non-Invasive Predictor for Lethal Arrhythmic Events in Hypertrophic Cardiomyopathy
Presence of fragmented QRS complex (frgQRS) of ECG has been recognized as a potential predictor of lethal ventricular arrhythmias in ischemic heart disease or cardiomyopathies, however the prognostic value of frgQRS in hypertrophic cardiomyopathy(HCM) is still unclear.
Methods: Of 494 consecutive HCM patients, 238 pathologically confirmed patients were enrolled (56 year-old, 145-male), in which we evaluated presence of frgQRS of 12-lead ECG associated with development of lethal arrhythmic events (VT/VF, sudden cardiac death (SCD), and appropriate ICD discharge). Electrophysiologic parameters and degree of fibrosis from RV biopsy samples or cardiac MR(CMR) imaging study were also evaluated.
Results: Eighty-eight (40%) patients had frgQRS of ECG, and 63 were implanted ICD. Presence of frgQRS was associated with QRS duration, LVEF, late potential of signal-averaged ECG, late gadolinium enhancement (LGE) in LV mass and tissue fibrotic change, in which, however, tissue fibrosis (p<0.001), CMR-LGE (p<0.01) and QRS duration (p<0.01) were independently correlated. During follow-up of 5.1 years, 2 patients died suddenly, and 35 had VT/VF events including ICD discharges (n=26). Presence of frgQRS (HR 4.3; p<0.0001), LVEF (HR 0.96; p<0.0001), and QRS duration (HR 1.12/ms; p<0.05) were associated with development of lethal arrhythmic events. Cox regression analysis revealed that frgQRS (RR 3.18; p<0.005) and LVEF (RR 0.96; p<0.0001) were the independent predictors for lethal arrhythmias. Presence of frgQRS indicated significant higher risk for lethal arrhythmias in patients with lower LVEF (≤50%) compared to those with preserved LVEF (>50%) (FigA). Thus combined evaluation of frgQRS with LVEF was useful to stratify the risk for lethal arrhythmias in HCM(FigB).
Conclusion: Presence of frgQRS in 12-lead ECG and lower LVEF were the important predictors for lethal arrhythmic events in HCM patients.
- © 2013 by American Heart Association, Inc.