TY - JOUR T1 - Mechanism of QRS electrical alternans. JF - Heart JO - Heart SP - 180 LP - 182 DO - 10.1136/hrt.77.2.180 VL - 77 IS - 2 AU - B. Brembilla-Perrot AU - H. Lucron AU - F. Schwalm AU - A. Haouzi Y1 - 1997/02/01 UR - http://heart.bmj.com/content/77/2/180.abstract N2 - In patients with latent dual atrioventricular nodal pathways a 2:1 ventriculoatrial block often occurs during ventricular pacing and is generally associated with the concomitant appearance of QRS alternans. This type of QRS alternans is related to retrograde conduction, and a concealed retrograde conduction in the His Purkinje system could explain the QRS alternans. A case that confirms the hypothesis that electrical alternans is secondary to a 2:1 block in the activation of some part of the ventricles is reported. ER -