An electrode cardiac catheter positioned across the tricuspid valve successfully recorded extracellular action potentials of the A-V node, His bundle, and right bundle branch in human subjects.
Observational
Demonstrates the feasibility of recording specialized conducting fibers in humans using an electrode catheter, foundational for clinical cardiac electrophysiology.
Extracellular action potentials of the A-V node (N), His bundle (H), and right bundle branch (RB) were recorded in subjects with an electrode cardiac catheter which was fluoroscopically positioned across the tricuspid valve. The N potential is a slow diphasic wave occurring between the atrial electrogram (P) and the H potential. It is characterized by slurring or notching on the upstroke. The H potential, as previously described, is a biphasic or triphasic wave of 15 to 20-msec duration. The RB potential is a fast biphasic wave of 10 to 20-msec duration occurring between the H potential and the Q wave. During single atrial pacing and premature atrial stimulation, the A-V conduction delay could be localized to the N-H interval. Evidence suggests that during aberrant ventricular conduction of the right bundle-branch block type the impulse was blocked proximally in the right bundle. During concealed conduction the nonconducted impulse was completely blocked within the A-V node or the N-H interval.
Damato et al. (1969) conducted an observational in Cardiac conduction. Electrode cardiac catheter recording was evaluated on Extracellular action potentials of the A-V node, His bundle, and right bundle branch. An electrode cardiac catheter positioned across the tricuspid valve successfully recorded extracellular action potentials of the A-V node, His bundle, and right bundle branch in human subjects.