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Electrophysiology study (or EP Study) is the process of stimulating the heart with small electrical impulses and recording electrical activity inside the heart. An electrophysiological (or electrophysiologic) study is the most accurate and reliable method of evaluating heart rhythms, allowing doctors to assess serious arrhythmias by stimulating the heart with small electrical impulses.
To do this, patients are brought to the electrophysiology laboratory, and thin catheters are placed through the leg veins, inside the heart. The catheters have electrodes at the tip and, like a pace maker, this allows small impulses to be given inside the heart, simulating aarhythmia. Based on the results, your doctor may recommend specific treatment options: catheter ablation, medication, surgery, and/or implantable cardioverter defibrillator (ICD) or a pacemaker.
Prior to your EPS, youll undergo a series of tests, including blood tests and an electrocardiogram (ECG). In some cases, you may be instructed not to take certain medications for several days before the EPS. Your physician will discuss specific risks of the EPS and answer any questions you may have about the procedure.
During an EPS, the doctor passes a thin, flexible wire through a vein in your upper thigh and sometimes the side of the neck to your heart. The wire records the hearts electrical signals. Your doctor uses the wire to provide minute electrical impulses to the heart to cause the heart to beat in a specific sequence. These extra beats may cause your heart to go into an arrhythmia. If an arrhythmia is produced, it frequently can be stopped by using another series of electrical impulses. Sometimes, if a serious heart rhythm is produced and you begin to pass out an electrical shock to the chest will be given to convert the rhythm immediately back to normal. Your doctor may also choose to do a catheter ablation, a procedure used to fix some types of arrhythmia, during an EPS.
Most procedures are out-patient, lasting anywhere from 2-6 hours. Patients are asked to limit activity the first 24 hours after the procedure. If the dressing over the groin was not removed in the hospital, you can remove it the day after the procedure. At the site of insertion, you my notice a lump about the size of a walnut. This is not abnormal and can last for about three to six weeks after the swelling goes down. Warm packs may help to dissolve it more quickly. It is also normal to experience some bruising around the insertion site. If the puncture sites continue to be painful or warm to the touch, show any signs of infection or become increasingly bruised and tender, call your physician.