Clinical outcome of monomorphic ventricular tachycardias after electrophysiological study in patients with maintained left ventricular ejection fraction

Abstract

Backgrounds : Ventricular tachycardia (VT) in patients with reduced left ventricular ejection fraction (LVEF) leads to sudden death. Mortality of patients with maintained LVEF has not been fully elucidated. We evaluated the relationship between clinical outcome and the inducibility of VT by electrophysiological study (EPS) in patients with comparatively maintained LV function.
Methods and Results : We retrospectively investigated consecutive 65 patients (55 men, 52±16 years) with structural heart disease, sustained monomorphic VT and LVEF≥35%who underwent EPS or CA between 2003 and 2009, including 21 individuals with ischemic heart disease, 13 with dilated cardiomyopathy, 3 with hypertrophic cardiomyopathy, 6 with sarcoidosis, 17 with ARVC, and 5 after operation for tetralogy of Fallot. ICD was implanted in 36 patients (55%) . During 43±21 months of follow-up, no patients died of any cause. Non-inducibility of VT at the end of procedures related to lower VT recurrence than patients with inducible VT (19%vs. 45%, p=0.028, log-rank) . Among 44 patients who underwent CA, non-induction related to less VT recurrence (18%vs. 55%, p=0.025, log-rank) . VT inducibility after CA was an independent predictor of VT recurrence (hazard ratio 3.38, p=0.04, Cox regression) .
Conclusions : Patients with VT and comparatively maintained LVEF had a favorable prognosis even with VT recurrence. Non-VT-inducibility at EPS or after CA demonstrated reduced risk of VT recurrence.