Body surface distribution of electrical potential during atrial depolarization and repolarization.

Electrical potential distribution surrounding the atria during depolarization and repolarization in the dog.

The potential distribution at the atrial surface during depolarization and repolarization was studied in intact dogs. A preparation was developed by implanting 30 to 40 miniature electrodes permanently on each atrium to record unipolar electrograms in the intact animal. Heart block was created to dissociate atrial and ventricular activity. The electrograms were recorded on magnetic tape and atr...

Body surface distribution of equipotential lines during atrial depolarization and ventricular repolarization.

Isopotential body surface maps and their relationship to atrial potentials in the dog.

The origin of body surface P waves was evaluated in the intact dog by recording body surface isopotential maps and atrial epicardial potential maps. P waves were recorded from 150 points on the body surface, and 80 atrial unipolar electrograms were recorded by means of permanently implanted atrial electrodes during normal sinus rhythm and during atrial pacing. When the atrial pacing sites were ...

Antiarrhythmic and Electrophysiologic Effects of Flecainide on Acutely Induced Atrial Fibrillation in Healthy Horses

BACKGROUND Only few pharmacologic compounds have been validated for treatment of atrial fibrillation (AF) in horses. Studies investigating the utility and safety of flecainide to treat AF in horses have produced conflicting results, and the antiarrhythmic mechanisms of flecainide are not fully understood. OBJECTIVES To study the potential of flecainide to terminate acutely induced AF of short...

Quantitative prediction of body surface potentials from myocardial action potentials using a summed dipole model.

This paper demonstrates quantitatively, using streamlined mathematics, how the transmembrane ionic currents in individual cardiac muscle cells act to produce the body surface potentials of the electrocardiogram (ECG). From fundamental principles of electrostatics, anatomy, and physiology, one can characterize the strength of apparent dipoles along a wavefront of depolarization in a local volume...