Programmed ventricular stimulation for risk stratification in patients with myocardial scarring and mildly reduced or...

Implantable cardioverter defibrillators (ICDs) are recommended in patients with left ventricular ejection fraction (LVEF) of ≤35%. However, no recommendation exists to guide the use of prophylactic ICD in patients with less altered LVEF and myocardial scarring, even though they represent most of sudden cardiac deaths.

This study aimed to evaluate the prognostic value of programmed ventricular stimulation (PVS) in patients with mildly reduced or preserved LVEF.

Patients who underwent PVS with myocardial scarring and LVEF of ≥40% were included. The primary endpoint was the occurrence of a major arrhythmic event (MAE), namely sudden cardiac death, ventricular tachycardia/fibrillation, and appropriate ICD therapy.

A total of 168 patients were included (mean age, 62 ± 13 years; LVEF, 54% ± 9%). Indication for PVS was mostly nonsustained ventricular tachycardia and/or syncope (83%). Patients with post-myocardial infarction represented approximately half of the cases (52%). Inducibility during PVS was observed in 21 patients (13%). Over a mean follow-up of 46 ± 38 months, an MAE occurred in 9 patients with positive PVS (43%) vs 4 patients (2.7%) with negative PVS. Inducibility during PVS provided high rule-out performance with a 97% negative predictive value for the prediction of MAE and a fair rule-in performance with a 43% positive predictive value (sensitivity 69%; specificity 92%).

PVS is a useful tool to discriminate patients with myocardial scar and LVEF of ≥40% at an increased arrhythmic risk. Effective utilization of ICD may be anticipated in the case of positive PVS, whereas noninducible patients are at a lower MAE risk.