What is an EP or electrophysiology study?

Heart rhythm problems often come and go in an unpredictable way. Sometimes it is difficult for doctors to catch an abnormal heart rhythm “event” even using sensitive tests such as an ECG (electrocardiogram), cardiac echo test, or Holter monitor.

An electrophysiology (EP) study uses one or more catheters (flexible tubes) threaded through a vein into your heart. The catheters are fitted with tiny sensors that measure the precise flow of electric signals through the heart.

During an EP study, a doctor can also use a catheter to provoke the unstable heart rhythm. Measurements recorded while the heart is in an unstable rhythm can help doctors determine its cause, where it starts, and even what medications control it best.
An EP study, or electrophysiology study, is a minimally invasive cardiac diagnostic procedure that involves placing specialized catheters in the heart through a patient’s blood vessels. These catheters allow a physician to see the heart’s electrical conduction with much greater detail than a surface electrocardiogram can provide. During an EP study, a physician can provoke an arrhythmia using several methods. An EP study can provide a definitive diagnosis of an arrhythmia and information essential in the selection of the appropriate treatment.
Atul Bhatia, MD
Clinical Cardiac Electrophysiology
During an electrophysiology (EP) study, two or more catheters (long, flexible wires) are inserted through veins in the leg, arm and/or neck into the heart. Then X-ray equipment is used to position the catheters in the chambers of the heart. The heart rhythm is monitored on a special screen to show the electrical pathway of each heartbeat.

For a normal heartbeat, an electrical signal starts in the sinus node and travels through the right and left atria, then through the AV node to the right and left ventricles. In some people, the signal starts elsewhere in the heart and follows an abnormal pathway. This can cause the heart to beat very slowly (bradycardia) or very quickly (tachycardia).
Abdul J. Tajik, MD
Cardiology (Cardiovascular Disease)
During an electrophysiology (EP) study electrode catheters are placed in the heart chambers to stimulate and determine the electric map of your heart rhythm. This helps your health care provider determine what abnormal rhythm you might be experiencing and what the best treatment would be for it.
An electrophysiological study (EP study) is an invasive procedure that tests the heart's electrical system. The electrical system of the heart generates the heartbeat.

During an EP study, a small, plastic catheter (tube) is inserted through a vein in the groin (or arm, in some cases) and is threaded into the heart, using a special type of x-ray, called fluoroscopy, to guide the catheter. Once in the heart, electrical signals are sent through the catheter to the heart tissue to evaluate the electrical conduction system contained within the heart muscle tissue.
An electrophysiology (EP) study is an invasive test to assess the heart’s electrical pathways. It is used to identify causes of abnormal heart rhythms (arrhythmias) and to provide therapies (called an ablation) to fix abnormalities in the electrical system of the heart.
An EP study is performed in the cardiac catheterization lab of a hospital. In this safe and controlled setting, your doctor will map your heart’s electrical pathways and intentionally try to reproduce the abnormal rhythm. Special catheters (thin, flexible tubes) are inserted into the vessels in the leg and neck. These catheters sense the small electrical currents within the heart. Special ablation catheters can heat or freeze the abnormal areas of heart tissue to alter the ability of these areas to create arrhythmias. If successful, it is possible that the person will no longer need to take medications to control their abnormal heart rhythms after an ablation procedure. Typically, an EP study is performed as an outpatient procedure.
In an electrophysiology study, one or more catheters are inserted into a major blood vessel and threaded to your heart. Doctors use tiny sensors on the catheters to capture and record your heart's activity, and may be able to identify the heart cells that are causing the problem.

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