Optical imaging of spiral waves: pharmacological modification of spiral-type excitations in a 2-dimensional layer of ventricular myocardium

Differential effects of sodium channel blockers, an I Kr blocker (nifekalant) and amiodarone on the spiral-type reentry, were investigated in rabbit hearts by using a high-resolution optical mapping system. Two-dimensional subepicardial layer of left ventricular myocardium with uniform anisotropy wa...

Full description

Saved in:
Bibliographic Details
Published in:Journal of electrocardiology 2005-10, Vol.38 (4), p.126-130
Main Authors: Kodama, Itsuo, Honjo, Haruo, Yamazaki, Mastoshi, Nakagawa, Harumichi, Ishiguro, Yuko, Okuno, Yusuke, Sakuma, Ichiro, Kamiya, Kaichiro
Format: Article
Language:English
Subjects:
Amiodarone
Amiodarone - pharmacology
Animals
Anisotropy
Anti-Arrhythmia Agents - pharmacology
Heart Conduction System - drug effects
Heart Conduction System - pathology
Humans
Myocardium - pathology
Nifekalant
Optical mapping
Pre-Excitation Syndromes - drug therapy
Pre-Excitation Syndromes - pathology
Pyrimidinones - pharmacology
Signal Processing, Computer-Assisted
Sodium channel blockers
Sodium Channel Blockers - pharmacology
Spiral reentry
Tachycardia, Ventricular - drug therapy
Tachycardia, Ventricular - pathology
Ventricular tachycardia
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Differential effects of sodium channel blockers, an I Kr blocker (nifekalant) and amiodarone on the spiral-type reentry, were investigated in rabbit hearts by using a high-resolution optical mapping system. Two-dimensional subepicardial layer of left ventricular myocardium with uniform anisotropy was prepared by endocardial cryoablation. During ventricular tachycardia (VT) elicited by cross-field stimulation, spiral-type excitations rotating around functional block lines (FBLs) were visualized. All the sodium channel blockers stabilized rotors; VT duration was prolonged in association with increases of FBLs and VT cycle length. The rotors in the presence of nifekalant were characterized by large meandering, long FBLs, and frequent front-tail interactions generating wave breaks. Amiodarone (acute application) increased FBLs and VT cycle length, but shortened the VT duration with minimal front-tail interaction. These results suggest that multifaceted drug action on both depolarization and repolarization may be required for the early termination of spiral-type reentry without causing breakup of rotors.
ISSN:0022-0736
1532-8430
DOI:10.1016/j.jelectrocard.2005.06.025