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 two basic types of
pacemakers:
- 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.
- 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.
Permanent pacemakers are surgically implanted into the
chest. The procedure to implant a pacemaker is considered minor surgery. It can
usually be done using
local anesthesia. 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.
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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