Electrophysiology is the branch of physiology that pertains broadly to the flow of ions (ion current) in biological tissues and, in particular, to the electrical recording techniques that enable the measurement of this flow.
An electrophysiology (EP) study is a test performed to assess your heart's electrical system or activity and is used to diagnose abnormal heartbeats or arrhythmia. The test is performed by inserting catheters and then wire electrodes, which measure electrical activity, through blood vessels that enter the heart.
Electrophysiologists, as the name suggests, deal with electricity--specifically, with the electrical impulses in the heart that control its rhythm and trigger heartbeats. The electrophysiologist is trained to diagnose and treat arrhythmias.
Tell your care team if you feel any pain. An EP study can take one to four hours. Your test may last longer if you're also undergoing cardiac ablation.