1. Nicholas Jackson et al. JACEP 2015;1:187-197
Purkinje Potentials Precede Local Activation in LDVF (A) Isochronal maps of ventricular activation from the bipolar endocardial electrograms shown in B. Apical electrodes are shown at the center and basal electrodes at the periphery. Eight beats of long-duration ventricular fibrillation (LDVF) are shown with earliest Purkinje activation represented by a star. Rapid endocardial activation can be seen to spread out across the septum via the Purkinje network, with latest activation consistently at the basolateral endocardium. On beats 5 and 6, separate focal activations away from the Purkinje system are also seen and contribute further to rapid endocardial activation. (B) VF on pseudosurface electrocardiography followed by 4 adjacent, endocardial bipolar traces from the left ventricular septum. Small, sharp Purkinje potentials can be identified preceding each local endocardial activation (arrows). It is also demonstrated that the frequency of activity shown on pseudosurface electrocardiography in LDVF is more rapid than the regional cycle length shown by the septal electrograms because it represents an amalgamation of the global myocardial activity.
Nicholas Jackson et al. JACEP 2015;1:
American College of Cardiology Foundation