title: Reversible cardiac conduction block and defibrillation with high-frequency electric field.
abstract: Electrical impulse propagation is an essential function in cardiac, skeletal muscle, and nervous tissue. Abnormalities in cardiac impulse propagation underlie lethal reentrant arrhythmias, including ventricular fibrillation. Temporary propagation block throughout the ventricular myocardium could possibly terminate these arrhythmias. Electrical stimulation has been applied to nervous tissue to cause reversible conduction block, but has not been explored sufficiently in cardiac tissue. We show that reversible propagation block can be achieved in cardiac tissue by holding myocardial cells in a refractory state for a designated period of time by applying a sustained sinusoidal high-frequency alternating current (HFAC); in doing so, reentrant arrhythmias are terminated. We demonstrate proof of concept using several models, including optically mapped monolayers of neonatal rat ventricular cardiomyocytes, Langendorff-perfused guinea pig and rabbit hearts, intact anesthetized adult rabbits, and computer simulations of whole-heart impulse propagation. HFAC may be an effective and potentially safer alternative to direct current application, currently used to treat ventricular fibrillation.
authors.affiliation: Department of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA.
authors.forename: Harikrishna
authors.initials: H
authors.lastname: Tandri
authors.forename: Seth H
authors.initials: SH
authors.lastname: Weinberg
authors.forename: Kelly C
authors.initials: KC
authors.lastname: Chang
authors.forename: Renjun
authors.initials: R
authors.lastname: Zhu
authors.forename: Natalia A
authors.initials: NA
authors.lastname: Trayanova
authors.forename: Leslie
authors.initials: L
authors.lastname: Tung
authors.forename: Ronald D
authors.initials: RD
authors.lastname: Berger
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac / Q000503:physiopathology / Q000628:therapy; D003198:Computer Simulation; D004554:Electric Countershock / Q000379:methods*; D004558:Electric Stimulation; D004560:Electricity; D006168:Guinea Pigs; D006329:Heart Conduction System / Q000503:physiopathology*; D066298:In Vitro Techniques; D008297:Male; D032383:Myocytes, Cardiac / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley