Heart and Vascular Center

Electrophysiology test (EP)

Electrophysiologic testing provokes known but infrequent arrhythmias. Using local anesthesia, temporary electrode catheters are positioned in the heart’s atria and/or ventricles and at strategic locations along the conduction system. They record cardiac electrical signals and “map” the spread of electrical impulses during each heartbeat. This shows where the heart blocks it.

The ability to electrically stimulate the heart at programmed rates and induce precisely timed premature beats allows your doctor to assess electrical properties of the heart's conduction system. Most significantly, it also triggers latent tachycardia or bradycardia. Induced tachycardias can usually be stopped by rapid pacing via the electrode catheters. Being able to "turn on" and "turn off" tachycardias during electrophysiologic studies allows antiarrhythmic drugs to be tested quickly for effectiveness. This can be done during a single study using intravenous therapy or during short follow-up studies with oral medication. Electrophysiologic testing has been performed safely worldwide; complications only rarely occur.