Investigations - Electrophysiological Study

An electrophysiologic (or EP) study investigates the electrical wiring of the heart. It is usually performed in patients with palpitations to make an accurate diagnosis of the arrhythmia causing the symptoms. It is carried out as a ‘key-hole’ procedure through a vein at the top of one, or sometimes both legs under local anaesthetic. Thin wires are passed painlessly into the heart where electrical recordings can be made and the heart’s response to electrical stimulation recorded. The test carries very little risk, although rarely damage to the leg vein can occur (approximately one in 500 cases). This can be repaired.

In many patients, particularly those with supraventricular arrhythmias, the doctor can then proceed directly to cauterise and eliminate the electrical problem causing the palpitations. See treatment section, catheter ablation.