An EP<unk>  is typically performed in an EP lab or cath lab. These are specially equipped operating rooms that usually contain an X-ray machine capable of acquiring live X-ray video images (a fluoroscope), equipment to record electrical signals from the heart, a stimulator to electrically excite the heart and control the heart rate, and ablation equipment to destroy abnormal tissue. A 3D navigation system that tracks and records the catheter position and associated electrical signals may also be used. The procedure may be performed awake under local anaesthetic, or under general anaesthetic. Monitoring equipment is attached including an automated blood pressure cuff and a pulse oximeter to measure the oxygen saturation of the blood. A peripheral venous cannula is generally inserted to allow medication to be given such as sedatives, anesthesia, or drugs. An access site that will allow catheters to be passed to the heart via an artery or vein is shaved and cleaned, usually in the groin. The blood vessels used to reach the heart (the femoral or subclavian veins, and sometimes the femoral artery) are punctured before a guidewire and plastic sheath are inserted into the vessel using the Seldinger technique. EP<unk>  and inducibility Once the catheter is in and all preparations are complete elsewhere in the lab, the EP<unk>  begins. The X-ray machine will give the doctor a live view of the heart and the position of the electrodes. He will guide the (steerable) electrodes to the correct position inside the heart. The electrophysiologist begins by moving the electrodes along the conduction pathways and along the inner walls of the heart, measuring the electrical activity along the way. The next step is pacing the heart, this means he/she will speed up or slow down the heart by placing the electrode at certain points along the conductive pathways of the heart and control the depolarization rate of the heart. The doctor will pace each chamber of the heart one by one, looking for any abnormalities. Then the electrophysiologist tries to provoke arrhythmias and reproduce any conditions that have resulted in the patient's placement in the<unk> . This is done by injecting electric current into the conductive pathways and into the endocardium at various places. Last, the electrophysiologist may administer various drugs (proarrhythmic agents) to induce arrhythmia (inducibility of VT/VF). If the arrhythmia is reproduced by the drugs (inducible), the electrophysiologist will search out the source of the abnormal electrical activity. The entire procedure can take several hours. Ablation If at any step during the EP<unk>  the electrophysiologist finds the source of the abnormal electrical activity, they may try to ablate the cells that are misfiring. This is done using high-energy radio frequencies (similar to microwaves) to effectively heat up the abnormal cells, to form scar tissue. This can be painful with pain felt in the heart itself, the neck and shoulder areas. A more recent method of ablation is cryoablation, which is considered less risky and less painful.
Electrophysiology study
Vectorcardiography
Cardiac electrophysiology
Evoked potential
Clinical neurophysiology
Magnetocardiography
Electroneuronography
Mechanomyogram