Centro Medico Excel

A pacemaker is an electronic device that sends impulses to the heart in order to help it maintain a normal rhythm. The device is implanted thru a small incision just below the collarbone.

What does the pacemaker do?

The pacemaker is designed to produce electronic impulses with the purpose of stimulating the heart when the normal physiological stimulation fails. These impulses, once generated, need a conductor cable, or electrocatheter, in order for it to work.

In what cases is the use of a pacemaker recommended?

Pacemakers, in general, are recommended when there is an irregular heart rhythm or an abnormal drop in heart frequency.

There are two main causes of an abnormal drop in heart frequency:

1. The inability of the sinoatrial node to produce the sufficient number of impulses per minute. When the node fails, it reduces its trigger frequency, and sometimes it produces long pauses during which the heart stops beating. The use of a pacemaker is recommended when symptoms like syncope, heart failure occur, as long as these symptoms are secondary to bradycardia (drop in heart frequency).
2. The failure in the conduction of the impulses produced by the node to the heart muscle. If there is a malfunction of the atrioventricular node, the use of a pacemaker is recommended depending on the gravity of the situation and the symptoms of the patient. If there is a complete atrioventricular blockage, the use of a pacemaker is highly recommended.

These two problems are usually the result of degenerative disease or atherosclerosis syndrome.

Types of pacemakers

Temporary pacemaker: the generator is not implanted in the patient, and can be:

• Transcutaneous (generally included in some defibrillators): the electrodes are placed on the skin, one the thorax (negative electrode) and the other one in the back (positive electrode).
• Intravenous (endocavitary): the electrodes are placed thru a central vein in contact with the endocardium.

Permanent pacemakers: the generator is implanted subcutaneous.

How is a pacemaker implanted?

A small incision is made below the left colorbone and a cable is introduced thru a vein all the way to the right atrium or the left ventricle (depending on the type of disorder). Then, when the cable is in place, the pacemaker is connected and placed below the skin. The procedure is finalized by closing the incision.