Extracellular detection of delayed afterdepolarization of cardiac fibers using signal averaging technique

摘要

Acetylstrophanthidin and resibufogenin both induced DAD in the intracellular recording and extracellu- lar DAD(DAD-E)in the extracellular electrogram in sheep heart Purkinje fibers. Acetylstrophanthidin and re- sibufogenin induced typical changes in the action potential including decrease in action potential amplitude, resting potential, maximum diastolic potential, and action poten- tial duration. Similar shortening occurred in the "Q-T interval" recorded by the extracellular electrogram. DAD can Be detected using the extracellular electrograms combined With the high resolution, signal averaging technique.