Electrophysiology Study

 Electrophysiology studies (EP studies) are carried out to measure the heart’s electrical activity along the conduction pathways and within the heart’s muscle cells themselves. Patients are often given some sedation prior to the procedure; this keeps them technically ‘awake’ during the procedure, but nice and relaxed they often cannot recall much of it afterwards. The studies are carried out in a specialised Cardiac Angiography Suite. A number of thin, flexible wires (or catheters) are inserted into the veins (or occasionally an artery) in the groins after local anaesthetic has been injected first to make the skin numb. The catheters are then guided up into the chambers of the heart using x-ray imaging. Only a very small amount of x-rays are normally used. The tip of each catheter has electrodes (rings of metal, often platinum) which measure the electrical activities of the heart, and these measurements can be used to identify any abnormal heartbeats or pathways, and locate where the abnormal heartbeats are being initiated. If an abnormality is found then it is common to proceed to catheter ablation to try and fix the problem at the same time.