Download Bradycardia - Heartistry

HEALTH CONDITIONS
BRADYCARDIA
What is it?
Bradycardia is an abnormally slow heartbeat, or
heart rhythm. An abnormal heart rhythm is called
an arrhythmia. Arrhythmias result from a
problem in your heart's electrical system.
A typical heart rate is about 60-100 beats per
minute. If you have bradycardia, your heart rate
is slower than 60 beats per minute. The slower
your heart beats, the less blood it pumps to your
body. If your heart beats too slowly, your body
may not get enough blood and oxygen to
function properly.
Another name for bradycardia: bradyarrhythmia.
What is the cause?
Bradycardia is caused by an abnormality in your heart's electrical system. In
some cases, your heart's natural pacemaker (the sinoatrial node) may not create
enough electrical signals in your heart. In other cases, the electrical signal does
not travel down the typical pathways. To learn more about your heart's electrical
system, go to the Heart & Blood Vessel Basics section.
However, the underlying cause of bradycardia varies from person to person.
Sometimes doctors cannot identify the cause. Other times bradycardia is caused
by aging, medications, or an existing heart condition.
What are the symptoms?
Some people with bradycardia don’t have any symptoms. Others may have
episodes of:
• Fatigue
• Shortness of breath
• Dizziness or fainting
• Chest pain
• Disturbed sleep
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Palpitations (feeling that your heart is racing or that your heartbeat is
irregular)
Even routine activities—going up a few stairs or walking to the mailbox—can give
you symptoms like shortness of breath. Usually the symptoms of bradycardia
appear gradually. People sometimes think the symptoms are due to aging, rather
than a heart problem.
What tests could I have?
To find out if you have bradycardia, your doctor may suggest one or more of the
tests listed below. The test results can also help your doctor choose the best
treatment(s) for you.
In some cases you may be sent to specialists for diagnosis and testing—and
sometimes for treatment. To learn more, go to the Your Treatment Team section.
Echocardiogram
Electrocardiogram (ECG or EKG)
Electrophysiology (EP) Study
Holter Monitoring
Stress Test
Echocardiogram
What is an echocardiogram?
An echocardiogram (also called an echo) is a three-dimensional, moving image
of your heart. An echo uses Doppler ultrasound technology. It is similar to the
ultrasound test done on pregnant women. The echo machine emits sound waves
at a frequency that people can't hear. The waves pass over the chest and
through the heart. The waves reflect or "echo" off the heart, showing:
• The shape and size of your heart
• How well the heart valves are working
• How well the heart chambers are contracting
• The ejection fraction (EF), or how much blood your heart pumps with each
beat
What can I expect?
When you have an echocardiogram, you undress from the waist up, put on a
hospital gown, and lie on an exam table. The technician spreads gel on your
chest and side to help transmit the sound waves. The technician then moves a
pen-like instrument (called a transducer) around on your chest or side. The
transducer records the echoes of the sound waves. At the same time, a moving
picture of your heart is shown on a special monitor. You may be asked to lie on
your back or your side during different parts of the test. You may also be asked
to hold your breath briefly so that the technician can get a good image of your
heart. An echo is a painless test. You feel only light pressure on your skin as the
transducer moves back and forth.
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Electrocardiogram (ECG or EKG)
What is an ECG?
An electrocardiogram (ECG or EKG) reveals how your heart’s electrical system is
working. The ECG senses and records your heartbeats, or heart rhythms. The
results are printed on a strip of paper. An ECG can also help your doctor
diagnose whether:
• You have arrhythmias
• Your heart medication is effective
• Blocked coronary arteries (in the heart) are cutting off blood and oxygen to
your heart muscle
• Your blocked coronary arteries have caused a heart attack
In all, there are three kinds of tests that record your heart's electrical activity,
each for a different period of time:
• Electrocardiogram (ECG)—done in the doctor's office. It records your heart
rhythms for a few seconds.
• Holter monitoring—records and stores (in its memory) all of your heart
rhythms for 24-48 hours.
• Event recorder—constantly records your heart rhythms. But it stores the
rhythms (in its memory) only when you push a button.
What are the parts of an ECG strip?
The peaks on an electrocardiogram (ECG) strip are called waves. Together, all
the peaks and valleys give your doctor important information about how your
heart is working:
• The P-wave shows your heart's upper chambers (atria) contracting
• The QRS complex shows your heart's lower chambers (ventricles) contracting
• The T-wave shows your heart's ventricles relaxing
The P-Q-R-S-T waves in a series reflect one heart beat.
What can I expect?
When you have an electrocardiogram (ECG) you undress from the waist up, put
on a hospital gown, and lie on an exam table. As many as 12 small patches
called electrodes are placed on your chest, neck, arms, and legs. The electrodes,
which connect to wires on the ECG machine, sense the heart's electrical signals.
The machine then traces your heart’s rhythm on a strip of graph paper.
Electrophysiology (EP) Study
What is an EP study?
An electrophysiology (EP) study is a test of your heart's electrical system. While
an electrocardiogram (ECG) gives an overview of your heart's electrical system,
the EP study gives a more in-depth view. The test helps find out details about
abnormal heart rhythms, called arrhythmias. The EP study can reveal:
• If you have an arrhythmia
• The cause of the arrhythmia
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Where the arrhythmia begins in the heart
If you are at risk for sudden cardiac arrest (SC)
The best treatment for an arrhythmia
The EP study begins when one or more leads are inserted into a blood vessel,
usually in the groin. The doctor gently "steers" the leads toward your heart. Once
in place, the leads sense your heart's electrical activity. One special lead also
delivers electrical signals to your heart to trigger an arrhythmia. That’s to help
find out how easily your heart can produce arrhythmias on its own.
During the EP study, your doctor closely monitors your heartbeats. If an
arrhythmia occurs, the doctor treats you with:
Medications given through the intravenous (IV) line in your arm or hand
Electrical signals delivered to the outside of your chest through patches
In some cases, ablation (a form of treatment) is done at the same time as your
EP study. (To learn about ablation, go to the Procedures part of the Medications
& Procedures section.) Or your doctor can suggest other types of treatment after
the EP study.
What can I expect?
Your test will be performed in a "cath lab." You undress, put on a hospital gown
or sheet, and lie on an exam table. An intravenous (IV) line put into your arm
delivers fluids and medications during the test. The medication makes you
groggy, but not unconscious. Patches called electrodes are put on your chest.
The electrodes monitor your heart's electrical signals during the test. A blood
pressure cuff on your arm also regularly takes your blood pressure.
The doctor makes a small incision (usually in the groin) for the catheter. The
groin area will be numbed so you shouldn't feel pain, but you may feel some
pressure as the catheter is inserted. If the doctor delivers electrical signals to
your heart, you might feel your heart racing or pounding. You won't be fully
asleep, so during the test your doctor or nurse might ask you questions.
Afterwards you may be in the hospital overnight, but most people have a fairly
rapid recovery.
Holter Monitoring
What is Holter monitoring?
Holter monitoring uses a small recording device called a Holter monitor. The
monitor tracks and records your heart's electrical activity, usually for 24-48
hours.
Holter monitoring can help your doctor find out if you have abnormal heart
rhythms, or arrhythmias. Arrhythmias might happen rarely, yet it is still important
for your doctor to know about them and to treat them.
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In all, there are three kinds of tests that record your heart's electrical activity,
each for a different period of time:
• Electrocardiogram (ECG)—done in the doctor's office. It records your heart
rhythms for a few minutes.
• Holter monitoring—records and stores (in its memory) all of your heart
rhythms for 24-48 hours.
• Event recorder—constantly tracks your heart rhythms. But it stores the
rhythms (in its memory) only when you push the button.
When the heart rhythms from any of these three tests are printed out, they all
look the same: the electrical signals look like peaks and valleys. A doctor may
suggest Holter monitoring when you have symptoms at least once every day or
two.
Your doctor may ask you to write down any symptoms you have during the test.
Symptoms might include faintness, dizziness, or fluttering in the chest. You
should note the time and how long the symptoms last. Your doctor might also ask
you to write down when you exercise, take medications, or get upset. This can
help your doctor see if there is a connection between your heart rhythms and
your symptoms or activities.
What can I expect?
As many as seven 4-7 sticky patches called electrodes are placed on your chest.
The electrodes connect to wires on the Holter monitor. The electrodes sense
your heart rhythms, while the monitor records and stores the rhythms. Since the
electrodes cannot get wet, you should shower or bathe before you begin the
Holter monitoring, and not at all during the testing. The Holter monitor device
itself is the size of a small portable tape recorder. It fits easily on a belt or can be
worn on a shoulder strap.
You should be able to do most or all of your daily activities at home and work
while using the Holter monitor. You won't feel anything while the Holter monitor is
tracking your heart rhythms, although the skin may become irritated from the
sticky patches. After 24-48 hours, you return the monitor. A technician examines
the recordings, notes whether you had any arrhythmias, and prepares a report
for your doctor.
Stress Test
What is a stress test?
A stress test is a type of electrocardiogram (ECG or EKG). Regular ECGs
examine how your heart beats at rest. Stress tests examine your heart’s
response to exercise, or stress. There are many variations of stress tests. But the
purpose of most stress tests is to find out if your heart is getting enough blood
and oxygen.
Stress tests are often done to reproduce symptoms like chest pain or shortness
of breath. The test looks at:
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Heart rate
Blood pressure
Your heart's electrical system
The test can show:
If you have coronary artery disease (CAD)
If you might be at risk for a heart attack
The cause of symptoms like chest pain (angina)
Whether you have irregular heart rhythms (arrhythmias)
Whether treatment—medications or an implanted device—has improved your
heart and blood vessel function
In one of the simpler types of stress tests, you walk on a treadmill or pedal a
stationary bike. You begin at an easy pace. The machine is slowly adjusted to
make you work harder. You continue exercising until you feel symptoms or until
you get too tired. A stress test is also known as an exercise test, a treadmill test,
or an exercise ECG.
During a nuclear stress test, the technician or nurse inserts an intravenous (IV)
line—usually in your arm. A small amount of a radioactive substance called
thallium is injected through the IV into your bloodstream. Usually a nuclear stress
test is done as part of a regular stress test, since the thallium can give your
doctor more information about whether your heart gets enough blood and
oxygen. But a nuclear stress test can be done even if you are unable to exercise,
since another medication can also be given to make your heart work harder.
After the thallium is injected, you lie on a table underneath a special camera. The
camera then takes images of your heart. Any part your heart that doesn't receive
enough blood and oxygen also receives less thallium. Therefore that part of your
heart shows up as a different color on the image.
What can I expect?
When you have a stress test you undress from the waist up and put on a hospital
gown. As many as 12 small patches called electrodes are placed on your chest,
neck, arms, and legs. The electrodes connect to wires on the electrocardiogram
(ECG). The machine then records the electrical activity in your heart from each of
the electrodes. A blood pressure cuff is also put on your arm, and your blood
pressure is checked often. If you have a nuclear stress test, you will also have an
IV inserted (usually into your arm).
A stress test itself does not usually cause any pain, although sometimes it
reproduces painful symptoms. However the test gives you a workout, since you
exercise until you're very tired. Usually a nurse talks to you and gives you
instructions throughout the test. The nurse continues to monitor your symptoms,
your blood pressure, and your heart rate for about 10-15 minutes after you stop
exercising.
What are the treatment options?
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Your treatment depends on your test results. Your doctor may recommend one
or more of these medications or procedures.
Medications
Antiarrhythmics
Procedures
Pacemaker Implant
MEDICATIONS
Tips for Taking Heart Medications
If you have a heart or blood vessel condition, you might want to know more about
some of the medications you take. The information in this section describes
some medications commonly prescribed for heart or blood vessel conditions. It
also includes some tips to help you take your medications as ordered.
Make sure you tell your doctor—or any new doctor who prescribes medication for
you—about all the medications and dietary supplements you take. Your doctor
can then help make sure you get the most benefit from your medications. Telling
your doctor this information also helps avoid harmful interactions between
medications and supplements.
You may also want to discuss these topics with your doctor or nurse each time
you get a new medication:
• The reason you're taking the medication, its expected benefits, and its
possible side effects
• How and when to take your medications
• If you take other medicines, vitamins, supplements, or other over-the-counter
products
In some cases, your heart needs several months to adjust to new medications.
So you may not notice any improvement right away. It also may take time for
your doctor to determine the correct dosage.
Blood tests are sometimes necessary for people who take heart medications.
The blood tests help your doctor determine the correct dosage—and therefore
help avoid harmful side effects.
Never stop taking your medication or change the dosage on your own because
you don't believe you need it anymore, don't think it's working properly, or feel
fine without it.
Be sure to talk to your doctor or nurse if you have:
• Questions about how your medications work
• Unpleasant side effects
• Trouble remembering to take your pills
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Trouble paying for your medications
Other factors that prevent you from taking your medications as needed
Questions about taking any of your medications
And don't hesitate to ask your pharmacist if you have questions about how and
when to take your medications.
Antiarrhythmics
Antiarrhythmics affect the electrical system in your heart. You can understand the
purpose of antiarrhythmics by looking at the root words of the term. Anti =
counter or against; arrhythmia = an abnormal heartbeat or heart rhythm.
Some generic (and Brand) names
All medications are approved by the Food and Drug Administration (FDA) for a
specific patient group or condition. Only your doctor knows which medications
are appropriate for you.
amiodarone (Cordarone, Pacerone)
disopyramide (Norpace)
dofetilide (Tikosyn)
flecainide (Tambocor)
procainamide (Procanbid)
propafenone (Rythmol)
quinidine (Quinaglute)
Sometimes other categories of medications—beta blockers and calcium channel
blockers—are used to help prevent arrhythmias.
What they're used for
To prevent and treat tachyarrhythmias (abnormally fast heartbeats, or heart
rhythms)
To restore normal heart rhythms
How they work
Antiarrhythmic drugs work in different ways to change the electrical activity in
your heart. Different drugs are used because the source of the arrhythmia can
come from different places in the heart.
Taking antiarrhythmics can:
Restore a normal heart rhythm
Reduce the chance for abnormally fast rhythms.
Pacemaker Implant
What is a pacemaker?
A pacemaker is a small implanted device that treats abnormal heart rhythms
called arrhythmias. Specifically, a pacemaker treats slow arrhythmias called
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bradycardia. A pacemaker can usually eliminate symptoms like shortness of
breath, fatigue, and dizziness caused by bradycardia.
Arrhythmias result from a problem in your heart's electrical system. Electrical
signals follow a certain path throughout the heart. It is the movement of these
signals that causes your heart to contract. During bradycardia, however, too few
signals flow through the heart. To learn more about your heart's electrical
system, go to the Heart & Blood Vessel Basics section.
A pacemaker restores your heart to a normal rhythm. The pacemaker can also
adjust to your body's needs. This is because the device has sensors that can
detect:
• When you rest and need a slow heart rate
• When you exercise and need a faster heart rate
Perhaps your heart does a good job of regulating your heart rhythm most of the
time. A pacemaker is used as backup treatment only when your heart needs it.
In other cases, a person’s heart can no longer create its own electrical signals, or
send them down the proper pathways. For example, sometimes aging, or an
ablation procedure in certain parts of the heart, can make particular therapy
necessary. In such cases the pacemaker might deliver continual treatment, in
order to cause each heartbeat.
The pacemaker delivers electrical signals to the heart. The device does this by
sending tiny amounts of electrical energy (too small to feel) to either the top or
the bottom chambers of the heart, or both.
A device implant is a procedure that uses local numbing. General anesthesia
usually is not needed.
An implanted device needs to be checked regularly to review information that is
stored in the device and to monitor settings.
How is the implant procedure done?
A pacemaker system has two parts.
Device—the device is quite small and easily fits in the palm of your hand. It
contains small computerized parts that run on a battery.
Leads—the leads are thin, insulated wires that connect the device to your heart.
The leads carry electrical signals back and forth between your heart and your
device.
Your doctor inserts the leads through a small incision, usually near your
collarbone. Your doctor gently steers the leads through your blood vessels and
into your heart. Your doctor can see where the leads are going by watching a
video screen with real-time, moving x-rays called fluoroscopy.
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The doctor connects the leads to the device and then tests to make sure both
work together deliver treatment. Your doctor then places the device just
underneath your skin and stitches the incision closed.
What can I expect?
Usually you are told not to eat or drink anything for a number of hours before the
procedure. You undress and put on a hospital gown or sheet. Your procedure will
be performed in a ”cath lab." You lie on an exam table and an intravenous (IV)
line is put into your arm. The IV delivers fluids and medications during the
procedure. The medication makes you groggy, but not unconscious.
The doctor makes a small incision near your collarbone to insert the leads. The
area will be numbed so you shouldn't feel pain, but you may feel some pressure
as the leads are inserted. You may be in the hospital overnight, and there may
be tenderness at the incision site. Most people have a fairly quick recovery.
Important Safety Information
Medications, procedures and tests can have some risks and possible side effects. Results may vary
from patient to patient. This information is not meant to replace advice from your doctor. Be sure to talk
to your doctor about these risks and possible side effects.
A pacemaker system can monitor and treat your heart rhythm by delivering electrical energy to pace
your heart when it senses a slow rhythm. But it is not for everyone, including patients with certain steroid
allergies. Patients who have additional medical conditions that may not allow the pacemaker to function
appropriately should not receive a device. Procedure risks include infection, tissue damage and kidney
failure. In some cases, the device may not respond to your heart rhythm. In rare cases severe
complications or device failures can occur. Electrical or magnetic fields can affect the device. Only your
doctor knows what is right for you.
Boston Scientific is a trademark and HEARTISTRY is a service mark of Boston Scientific Corporation.
All other brand names mentioned are used for identification purposes only and are trademarks of their respective owners.
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