What is Cardiac Electrophysiology?
Cardiac electrophysiology is the study of the heart's electrical system. The term "electrophysiology study" or "EP study" applies to any procedure that requires the insertion of an electrode catheter into the heart. Electrode catheters are long, flexible wires that transmit electrical currents to and from the heart.

Some electrophysiology studies are done to diagnose abnormalities (see Heart Rhythm Problems and Conditions ), while others are done to access the heart for treatment or correction of certain conditions, such as Pacemaker Implantation, ICD Insertion, or Cardiac Ablation.

Electrical Impulses Keep Your Heart Pumping
The heart's electrical system controls the rhythmic contractions that keep the blood pumping and circulating throughout your body. These electrical impulses are controlled by the sinus node, a group of specialized cells that act as the heart's natural pacemaker.

Why is good blood circulation important?
Blood is rich with the oxygen and nutrients that keep our cells alive and functioning, so a strong circulation of blood throughout the body is a vital component of good health. Electrical signals from the sinus node keep the heart contracting at a healthy pace, which controls the rate of blood that is pumped to nourish and energize the body.

How does the heart control blood circulation?
The heart is a muscular pump that serves as the master control station for blood circulation. The heart is divided into four chambers. The upper chambers are called the right and left atrium, and the lower chambers are called the right and left ventricle.

Blood from all parts of the body drains into the right atrium, passes through a valve and reaches the right ventricle. The right ventricle contracts with each heartbeat and blood is pushed into the lungs, where it gives off carbon dioxide, takes up oxygen, and returns via the pulmonary veins to the left atrium. During relaxation of the left ventricle, the blood passes from the left atrium to the left ventricle where, with each heartbeat, it is ejected through the aortic valve into the aorta. From the aorta, blood flows through the circulatory system to nourish the organs and tissues of the body.

Why is the heart's electrical system so important to good blood circulation?
The heart's electrical system transmits signals throughout the heart that keep it pumping at a healthy pace. Beginning in the sinus node, these electrical impulses then travel through pathways of the heart's upper chambers, which causes them to contract and squeeze blood into the ventricles. Electrical impulses then spread to the atrioventricular node, or AV node, which buffers them before they pass through the ventricles. Specialized muscle fibers running through the ventricles distribute the impulses that cause them to contract and pump blood.

How do problems with the electrical system affect blood circulation?
When there is a problem with the heart's electrical system, its pumping power is diminished and blood does not circulate effectively. The body does not get the full supply of oxygen that it needs to thrive. This can cause irregular heart rhythms and conditions.