Fragmented QRS Predicts Cardiovascular Death of Patients with Structural Heart Disease and Inducible Ventricular Tachyarrhythmia

Background: Fragmented QRS (fQRS) can predict cardiac events, and inducible ventricular tachycardia/fibrillation (VT/VF) is a known high-risk factor for arrhythmic death. However, whether fQRS is a predictor of cardiac events in patients with inducible VT/VF is unknown. We aimed to evaluate whether fQRS is a predictor of cardiac events in patients with structural heart disease and inducible VT/VF.

Methods And Results: We retrospectively investigated 98 patients with structural heart disease who had a defibrillator device implanted. All patients underwent electrophysiological testing prior to or after device implantation and VT/VF was induced. fQRS was present in 30 patients. Appropriate defibrillator therapies were similar between the fQRS and non-fQRS groups (47% vs. 47%). In total, 25 patients (26%) died during a mean follow-up period of 87±43 months. All-cause mortality (12 [40%] vs. 13 [19%]) and cardiovascular deaths (9 [30%] vs. 4 [6%]) were significantly higher in the fQRS group than non-fQRS group, respectively; Kaplan-Meier analysis revealed significantly lower event-free survival for all-cause mortality (P=0.012) and cardiovascular deaths (P=0.001) for fQRS patients. A multivariable Cox regression model revealed that fQRS was an independent predictor of cardiovascular death (hazard ratio, 4.58; 95% confidence interval, 1.34-15.64; P=0.015).

Conclusions: fQRS is a predictor of cardiovascular death in patients with structural heart disease and inducible VT/VF.