Circus movement in canine right ventricle.

Mapping of ventricular tachycardia induced by programmed stimulation in canine preparations of myocardial infarction.

To investigate the mechanism of uniform ventricular tachycardia induced by programmed stimulation, we recorded His bundle electrograms and unipolar electrograms from 64 subepicardial, subendocardial, and intramural sites in dogs. Isochronal maps were generated off-line by computer. Two groups of dogs were studied 3 days after occlusion of their left anterior descending coronary arteries; one gr...

A Unified Functional/Anatomic Substrate for Circus Movement A Rutter: Activation and Refractory patterns the Canine Right A Enlargement Model

Slow conduction and reentry in the ventricular conducting system. II. Single and sustained circus movement in networks of canine and bovine Purkinje fibers.

Closed loops of fibers of the ventricular conducting system of canine or bovine hearts were used to study circus movement of excitation. Action potentials were recorded at three sites with intracellular microelectrodes. Discrete segments were depressed by application of K-rich agar or the entire loop was depressed by modified Tyrode's solution containing 15—17 DIM K and 1 to 5 X 10~M epinephrin...

Atrioventricular and Ventriculoatrial Excitation in Wolff - Parkinson - White Syndrome ( Type B )

A patient with an atrial septal defect, paroxysmal tachyeardia, and the WolffParkinson-White syndrome (type B) had epicardial exploration to determine the nature of the excitation anomaly. Right bundle-branch block in association with the WPW syndrome (type B) was evidenced by the late activation (0.12 sec) of the epicardium over the outflow tract of the right ventricle. Early activation of the...

Atrioventricular and ventriculoatrial excitation in Wolff-Parkinson-White syndrome (type B). Temporary ablation at surgery.

A patient with an atrial septal defect, paroxysmal tachyeardia, and the WolffParkinson-White syndrome (type B) had epicardial exploration to determine the nature of the excitation anomaly. Right bundle-branch block in association with the WPW syndrome (type B) was evidenced by the late activation (0.12 sec) of the epicardium over the outflow tract of the right ventricle. Early activation of the...