Intermittent ventricular pre-excitation

Background: Intermittent ventricular pre‐excitation has long been considered a low‐risk marker for sudden death. Accessory pathways (APs) with high‐risk intermittent antegrade conductive properties may exist, but this still represents a gray area in current guidelines. We evaluated differences in risk characteristics between symptomatic and asymptomatic patients with intermittent pre‐excitation (IPX) and those with persistent pre‐excitation (PPX) in a multicenter international registry. Methods: 392 consecutive patients [IPX: 79 (20.15%)