The effects of remodeling with heart failure on mode of initiation of ventricular fibrillation and its spatiotemporal organization.

Purpose: The effect of the heart failure substrate on the initiation of ventricular fibrillation (VF) and its resulting mechanism is not known. The objective of this study was to determine the effects of substrate on VF initiation and its spatiotemporal organization in the heart failure model.

Methods: Optical action potentials were recorded from LV wedge preparations either from structurally normal hearts (control, n = 11) or from congestive heart failure (CHF; n = 7), at the epicardial surface, endocardial surface which included a papillary muscle, and a transmural cross section.

Transmural characteristics of atrial fibrillation in canine models of structural and electrical atrial remodeling assessed by simultaneous epicardial and endocardial mapping.

Background: Epicardial mapping has shown that atrial substrate may play a role in the characteristics of the resulting atrial fibrillation (AF). However, it is not known whether these differences also occur in 3 dimensions.

Objective: This study sought to examine the 3-dimensional characteristics of AF by simultaneously analyzing AF on the epicardial and endocardial surfaces.