What is Electrophysiology (EP)?

Electrophysiology is the branch of cardiology that deals with problems related to the electrical system of the heart. A cardiologist who specializes in the diagnosis and treatment of problems related to heart rhythm is an Electrophysiologist.

• The normal electrical system of the heart causes the heart to beat in a regular manner to supply the body and the various organs with blood supply necessary for the different levels of activities we perform.
• Electrical impulses in the heart are generated by two main “pacemakers” and conducted by certain electrical “cables” or pathways.
• Abnormal electrical impulses cause the heart to beat too slow, too fast or in an irregular, chaotic fashion. One example is atrial fibrillation.

What does a person with an abnormal heart rhythm feel?

A person may experience one or more of the following symptoms:

The flow of electrical impulses from one part of the heart to another causes the heart to:

• Contract and relax, thus pumping blood to the body.
• The flow of electrical impulses in the heart is called conduction. So, when the heart rate is too slow, we conclude that the conduction of impulses is taking longer time than it should normally take.
• A diseased pacemaker or diseased tissues in the heart can cause conduction problems. Sometimes a slow heart rate can be caused by side effects of certain medications.
• Any part of the heart muscle can generate electrical impulses. If conduction flows through an abnormal pathway, it may cause the heart rate to be either too fast or irregularly.
• In the Electrophysiology Lab problems related to heart rhythm can be diagnosed and a suitable treatment can be followed.
• An electrophysiology study is a procedure during which a rhythm problem can be identified and possibly treated.

What kinds of procedures are performed in the EP Lab?

Implantation of Cardiac Pacemakers, Defibrillators, and Biventricular Pacemakers-Defibrillators

1. Special kinds of pacemakers and defibrillators are implanted to treat slow heart rate , congestive heart failure, or to prevent sudden cardiac death.
2. Some abnormally fast heart rates are lethal. These originate from the bottom chambers of the heart. When these chambers beat too fast, the heart loses its ability to pump enough blood supply to the vital organs, especially the brain, resulting in loss of consciousness. Death may occur if this problem is not corrected within a few minutes. Patients with this kind of a problem may need an implantable defibrillator. This is a device capable of identifying lethal arrhythmias and delivering a low-voltage shock to the heart to restore normal rhythm.

Electrophysiology Study and Radiofrequency Ablation

1. The electrical system of the heart can be studied to identify certain conduction problems and abnormal heart rhythms.
2. Abnormally fast heart rates can be induced, diagnosed, and their exact point of origin can be located.
3. The spot generating the abnormally fast heart rate can be destroyed and rendered inactive, thus eliminating the problem. The amount of tissue destroyed is very tiny (the size of the tip of a pencil), and would not affect the function of the heart muscle. This curative procedure is called radiofrequency ablation.

How is an Electrophysiology study done?

• The EP Lab is similar to the laboratory used for heart catheterization. During the procedure, the patient is given medications to help him or her relax or sleep.
• Special wires, called catheters, are placed in strategic areas of the heart. These catheters record electrical activity inside the heart and allow the physician (electrophysiologist) to artificially “pace” the heart.
• An x-ray machine allows the physician to monitor the catheters to see that they are properly placed. The patient receives only intermittent, low doses of x-rays.
• Following the study, the findings and recommendations will be explained to the patient and family members.
• If an ablation is necessary, a special catheter is used to apply thermal heat to burn and eliminate the precise location in the heart that the arrhythmia originates from.
• During any electrophysiology procedure, the patient is safely monitored by a highly trained team of doctors and nurses.