Treatment Overview
A pacemaker is a battery-powered device about the
size of a pocket watch that sends weak electrical impulses to “set a pace” so
that the heart is able to maintain a regular heartbeat.
There are
different types of pacemakers, so your doctor will work with you to decide what
kind will be best for you.
- Single-chamber pacemakers stimulate one chamber of the heart, either an upper chamber
(atrium) or, more commonly, a lower one (ventricle).
- Dual-chamber pacemakers send electrical impulses to both
the atrium and the ventricle and pace both chambers. A dual-chamber pacemaker
synchronizes the rhythm of the atrium and ventricles in a pattern that closely
resembles the natural heartbeat. Dual-chamber pacemakers are often used to
treat a slow heart rate.
- Biventricular pacemakers pace the rhythm of the heart's lower chambers (ventricles) so
that the chambers contract at the same time. Biventricular pacemakers are used
in people who have heart failure and problems with the heart's electrical
system. Biventricular pacemakers are also called cardiac resynchronization
therapy (CRT).
Most new pacemakers are rate-responsive, or physiologic,
pacemakers. This type of pacemaker varies its rate to cause the heart to beat
faster when you are exercising to meet your body's increased needs or slower
when you are at rest. Another type, the fixed-rate pacemaker, sends electrical
impulses at a set rate that does not vary either faster or slower. Both types
of pacemakers kick in when the heart rate drops to a predetermined "slow"
level.
Some pacemakers are a combination of a pacemaker with an
implantable cardioverter-defibrillator (ICD). This
combination pacemaker and ICD is used for people who need a pacemaker and also
have a risk for abnormal heart rhythms.
Permanent pacemakers are
surgically implanted into the chest. See a picture of
pacemaker placement.
The procedure to implant a pacemaker is
considered minor surgery. It can usually be done using
local anesthesia. Your doctor will make a small
incision in your chest wall just below your collarbone. He or she then usually
threads the pacemaker wires (leads) through the incision into a large blood
vessel in the upper chest and into the heart. Your doctor uses X-rays to place
the leads in the heart. Using the same incision, your doctor creates a small
pocket under the skin to hold the pacemaker. He or she then attaches the leads
to the pacemaker. The procedure takes about an hour.
Permanent
pacemakers are powered by batteries. The batteries usually last 5 to 15 years
before they need to be replaced.
Temporary pacemakers are located
outside the body and attached to the heart by a wire threaded through a neck
vein or leg vein or through the chest wall. Temporary pacemakers are most
commonly used for a short time following heart surgery or in emergency
situations.
What To Expect After Treatment
Most people stay overnight in the
hospital after having a pacemaker implanted and typically go home the next day.
But sometimes, the surgery is done as an
outpatient procedure, which means you do not need to
stay overnight in the hospital.
Most people return to normal
activities after a few weeks. You should avoid driving or participating in
vigorous physical activity that involves the upper body for several weeks after
having a pacemaker implanted.
About twice a year your doctor will
check your pacemaker and adjust it, if needed. In
between checkups, you may be asked to send information from your pacemaker to
your doctor or clinic over the telephone (telephone monitoring).
Why It Is Done
Historically, pacemakers have been
used to treat slow heart rates by sensing when the heart rate falls below a
certain rate and then pacing the heart to increase it to a set rate. But newer
rate-responsive pacemakers can alter the heart rate to a faster or slower rate
based on your activity.
How Well It Works
Pacemakers stimulate the heart to
speed up when it beats too slowly. They can also substitute for the natural
pacemaker of the heart (SA node) or the heart tissue that
regulates the beating of the ventricles (AV node).
Risks
Pacemakers allow people to return to normal,
active lives. Most people have very few limitations, if any. But some
activities and situations can interrupt the signals sent by the pacemaker to
the heart. You may need to modify some of your activities. Follow your doctor's
specific instructions about care and precautions if you have a
pacemaker.
Risks during the procedure to implant a pacemaker
include:
- Puncture of the
heart.
- Bleeding.
- Difficulty
breathing.
- Irregular heart
rhythms.
- Infection.
- Blood clot.
- Pacemaker
malfunction.
What To Think About
In rare cases, people feel
throbbing in the neck, chest fullness, or lightheadedness when the pacemaker
sends out impulses. Talk to your doctor about what types of side effects you
may expect from your pacemaker.
Rate-responsive pacemakers are
often the ideal choice for active people. These pacemakers closely reproduce
natural heart rhythms and are able to raise heart rate in response to physical
activity. Your doctor can decide how fast the pacemaker should respond and how
quickly your heart rate should return to a resting rate.
Strong
electric or magnetic fields can interfere with your pacemaker. You can safely
use most household and office equipment. And you can usually avoid electrical
interference from magnetic or electrical sources by keeping certain things a
few inches away from your pacemaker. You should completely avoid things like
heavy electrical or industrial equipment.
You may walk through
metal detectors (in airports or other security checkpoints) at a normal speed,
but avoid standing near or leaning on these systems. Your pacemaker may set off
a metal detector, but the security archways will not damage the device. Your
doctor will give you a pacemaker identification card to carry at all times.
Before you pass through a metal detector, tell the security guards that you
have a pacemaker, and show them your device identification card.
If you have a pacemaker, you will not be able to have an MRI (magnetic
resonance imaging) test. Before you have any tests or surgery, tell all of the
health professionals involved in your care that you have a pacemaker. You may
choose to wear a medical alert bracelet that says you have a pacemaker. Experts
are trying to make pacemakers that can work safely during an MRI test.
Heart problems: Living with a pacemaker or ICD
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