Electrophysiology / Pacemaker and Defibrillator Services

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Heed Heart Attack Warning Signs

Anyone who has chest pain that worsens over a five-minute period should call for emergency medical help, according to new guidelines released by the American Heart Association (AHA). Worsening chest pain, especially if accompanied by shortness of breath, weakness or lightheadedness, can be a sign of a heart attack. The more quickly a person having a heart attack is treated, the more likely the person is to survive without long-term complications, the AHA says. Other symptoms of a heart attack include pain in the arms, back, neck, jaw or stomach. Not everyone having a heart attack experiences typical symptoms. The more signs and symptoms you have, the more likely that you are having a heart attack.

Physicians specializing in cardiac electrophysiology perform pacemaker and defibrillator implants in our Cardiac Catheterization Lab.

An electrophysiologist is a doctor who diagnoses and treats problems with your heart's electrical system, such as abnormal heart rhythms.


The heart's electrical system helps it beat at a healthy, normal speed (pace). Slow heart rhythms can happen in people who have healthy hearts, or in people with heart disease. Symptoms of “too slow” heart rhythm can include fatigue, light-headedness, palpitations, shortness of breath and dizziness.


An abnormally fast rhythm is another problem that can occur with the heart's electrical system. Two types of dangerous fast rhythms, called ventricular tachycardia and ventricular fibrillation, can cause shortness of breath, fainting and cardiac arrest. Milder symptoms could include palpitations, chest pain or shortness of breath. Fast heart rhythms generally occur in people with scars on their hearts from heart attacks or coronary heart disease, or in people with cardiomyopathy (a condition due to a weakened heart muscle).


Pacemakers and defibrillators are devices sometimes used to treat abnormal heart rhythms.


Pacemakers and Defibrillators – Answers to Common Questions
Your doctor is the best person to determine if you are a good candidate for a pacemaker or defibrillator implant. Here is are answers to frequently asked questions about pacemakers and defibrillators provided by our heart care experts:

What is a pacemaker?
A pacemaker is a small electronic device that helps your heart beat at a regular pace. The pacemaker’s generator is the size of a half-dollar and contains the battery as well as a small computer. The pacemaker’s leads are thin flexible wires attached to the generator on one end and the heart on the other end.

If the heart is beating regularly, the pacemaker doesn’t do anything; it just waits to see if the heart tries to beat too slow. When the leads see that the heart is beating too slow, a message is sent to the generator, which then tells the leads to make the heart’s rhythm a little bit faster. It does this by sending a small electrical charge through the leads and into the heart, which then makes it beat and squeeze. The electrical charge is not very much, and people who have pacemakers cannot feel when the pacemaker is working. The electrical charge does not hurt the heart in any way. Top >

How is a pacemaker placed in the body?
An approximately two-inch incision is made in the chest just below the collarbone. A pocket is created under the skin. Pacemaker leads are placed through the incision and into a vein that runs under the collarbone. Using an X-ray monitor, the leads are then threaded through the vein into the heart. The leads are then attached to a generator. The generator and leads are then placed into the pocket under the skin, and the incision is “closed” with internal stitches. The entire procedure takes about 60-to-90 minutes. Top >

What is a defibrillator?
An electronic device called an Implantable Cardioverter-Defibrillator (ICD or defibrillator) can help the heart stay in a normal rhythm. A defibrillator is placed in people who have had a cardiac arrest, or in people who are in danger of having a cardiac arrest. A defibrillator’s generator is about three times the size of a pacemaker. The generator serves as the “brains” of the defibrillator. The defibrillator’s leads are thin flexible wires that are attached to the generator on one end and the heart on the other end. The leads serve as both the “eyes” and the “arms” of the defibrillator. If the heart is beating regularly, the defibrillator doesn’t do anything; it just waits to see if the heart tries to beat too fast.

When the leads see that the heart is going too fast, a message is sent to the generator, which then tells the leads to shock the heart. It does this by sending an electrical charge through the leads and into the heart, which then makes the heart go back to a normal rhythm. Unlike with a pacemaker, this electrical charge is felt by the patient as a shock, which is very uncomfortable. However, it does stop a potentially life threatening fast heart rhythm.


Another feature of defibrillators is that all modern defibrillators have the ability to pace the heart if it tries to get too slow. That is, the generator contains a computer that detects when the heartbeat is either too fast or too slow, and can fix both problems. It can serve as both a pacemaker and as a defibrillator.
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How is a defibrillator placed in the body?

Implantation of a defibrillator is similar to implantation of a pacemaker. The entire procedure takes about two hours. Top >

What happens after the procedure?

Patients usually go home the day after receiving either a pacemaker or defibrillator implant, and must take it easy for the first two weeks. Patients can return to work in five to seven days, but should avoid any strenuous activity for approximately four weeks. Generators will have to be changed every five to eight years on a pacemaker and every five years on a defibrillator. Top >

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Hendricks Regional Health is a hospital system with medical facilities and a physician group serving residents of Hendricks County in suburban Indianapolis, Indiana (IN), including the towns of Avon, Bainbridge, Brownsburg, Danville, Greencastle, Lizton, Monrovia and Plainfield.
1000 East Main Street Danville, Indiana 46122 Phone: (317) 745-4451
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