Cardiac Mapping What's it for An electrophysiology study, or EP study for short, is used to find out what is causing a heart rhythm problem like an arrhythmia. Electrophysiology is the branch of cardiology that deals with the electrical patterns in your heart. How it's done EP studies are done in the EP Lab at the University of Rochester Medical Center. An electrophysiologist, a doctor with special expertise in the heart’s electrical systems, will perform your study. You are given a medication to help you relax and a local anesthetic. A small incision is made in your thigh or in your neck. One or more thin, flexible tubes called catheters are then inserted into the incision and carefully guided through your blood vessels and to your heart. The ends of these catheters have tiny electrodes. The electrodes allow the electrophysiologist to gather data about the electrical signals that are flowing through your heart, helping to pinpoint the cause of your heart rhythm problem. The electrodes can also provide tiny electrical impulses to your heart. The pulses can be used to safely “turn on” an arrhythmia and to identify the problem area. Your doctor can then test various medications or electrical impulses to see if they are able to “turn off” the arrhythmia, helping to determine the best treatment for you. In some cases, a procedure called an ablation will also be performed. Ablations can often cure an arrhythmia by painlessly inactivating a small region of abnormal tissue inside the heart. An EP study typically takes about two hours and does not require general anesthesia. Many patients stay awake during the study and sometimes ask questions, while other patients fall asleep. Technology and expertise at URMC The University of Rochester Medical Center is considered a world leader in electrophysiology. Our research on heart rhythm disorders and treatments has helped improve treatments for patients around the globe. We have three fully-equipped electrophysiology labs for the diagnosis and treatment of heart rhythm disorders. Our labs are staffed by nurses and technicians who work exclusively with patients who have heart rhythm disorders. Our newest lab include robotic navigation for radiofrequency ablation. This advanced technology gives us even greater precision, versatility and safety. The EP Lab at URMC performs thousands of cases every year. Who to contact If you need additional information on the EP Lab at URMC, please call us at (585) 275-4775.