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Electrophysiology is the science that studies your heart’s electrical activity. Studying this activity can detect problems with your heart rate or rhythm that can put you at high risk for heart disease and heart rhythm abnormalities. Once properly diagnosed, arrhythmias can be managed or even cured.

Electrophysiology study

This is a detailed study of the heart’s electrical system and is used to see if you have a heart rhythm disturbance, and if so, where it is coming from. During the procedure, a long, flexible wire called an electrode catheter is placed in your heart. This diagnostic study will show your doctor what treatment is best for you: a pacemaker, an automatic implantable cardiac defibrillator, cardiac resynchronization therapy or a catheter ablation. All these are explained here.

Pacemaker insertion and maintenance

A pacemaker is a small, battery-operated device that helps maintain a normal heart rhythm. It sends electrical signals to the heart to stimulate the heart muscles to pump. Pacemakers are designed for patients who have irregular or very slow heart rates that can lead to weakness, fatigue, dizziness, fainting or death.

A pacemaker is placed under the skin near the left or right collarbone. It has wires that are put inside the heart to measure the heart’s electrical activity and, if needed, transmit signals that cause the muscles to pump. The doctor sets the pacemaker’s rate.

We provide pacemaker checkups over the phone and Internet as well as pacemaker clinics.

Automatic implantable cardioverter defibrillator (AICD) insertion and maintenance

An AICD is similar to a pacemaker, but while a pacemaker is usually used to correct a heart rhythm that is too slow, an AICD is used to correct a heart rhythm that is too fast. For patients who have both problems, the doctor will choose an AICD to pace the heart as needed.

An AICD is placed under the skin near the collarbone much like a pacemaker. It has wires that are put inside the heart to measure and monitor the heart’s electrical activity and, if needed, correct an abnormal rhythm. The doctor programs the AICD’s required function.

The doctor checks the AICD’s function at regular checkups as well as AICD clinics.

Cardiac resynchronization therapy (CRT)

When heart muscles become damaged and weak, they can no longer pump effectively. Heart rhythms lose their pace and become uncoordinated. This leads to congestive heart failure (CHF). Cardiac resynchronization therapy can relieve CHF symptoms by improving the coordination of the heart’s contractions.

A device similar to a pacemaker is placed under the skin near the collarbone. It is used to restore coordinated contractions, leading to a better heart beat and better quality of life.

The doctor checks the CRT’s function at regular checkups.

Catheter ablation

This procedure is used to treat problems with the rate or rhythm of the heartbeat (cardiac arrhythmia). During catheter ablation, a long, thin, flexible tube is put into a blood vessel in your arm, groin (upper thigh) or neck. This tube is called an ablation catheter. It’s guided into your heart through the blood vessel.

Energy is delivered through the ablation catheter to your heart. The energy corrects small areas of heart tissue where abnormal electrical circuitry may cause an arrhythmia to start.

There are two types of ablation:

  • Radiofrequency (RF) ablation. This type of energy uses radio waves to produce heat that disrupts the abnormal heart circuit. Studies have shown that RF energy is safe and effective.
  • Cryotherapy. Here, an extremely cold temperature, as low as -75°C, is used to freeze targeted cells so they no longer interfere with electrical messages that control the heart’s rhythm.

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