Arrhythmia Heart
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What is an arrhythmia?
An arrhythmia is a change in the regular beat of the heart. The heart may seem
to skip a beat or beat irregularly or very fast or very slowly.
Does having an arrhythmia mean that a person has heart disease?
No, not necessarily. Many arrhythmias occur in people who do not have
underlying heart disease.
What causes arrhythmias?
Many times, there is no recognizable cause of an arrhythmia. Heart disease may
cause arrhythmias. Other causes include: stress, caffeine, tobacco, alcohol,
diet pills, and cough and cold medicines.
Are arrhythmias serious?
The vast majority of people with arrhythmias have nothing to fear. They do not
need extensive exams or special treatments for their condition. In some
people, arrhythmias are associated with heart disease. In these cases, heart
disease, not the arrhythmia, poses the greatest risk to the patient. In a very
small number of people with serious symptoms, arrhythmias themselves are
dangerous. These arrhythmias require medical treatment to keep the heartbeat
regular. For example, a few people have a very slow heartbeat (bradycardia),
causing them to feel lightheaded or faint. If left untreated, the heart may
stop beating and these people could die.
How common are arrhythmias?
Arrhythmias occur commonly in middle-age adults. As people get older, they are
more likely to experience an arrhythmia.
What are the symptoms of an arrhythmia?
Most people have felt their heart beat very fast, experienced a fluttering in
their chest, or noticed that their heart skipped a beat. Almost everyone has
also felt dizzy, faint, or out of breath or had chest pains at one time or
another. One of the most common arrhythmias is sinus arrhythmia, the change in
heart rate that can occur normally when we take a breath. These experiences
may cause anxiety, but for the majority of people, they are completely
harmless. You should not panic if you experience a few flutters or your heart
races occasionally. But if you have questions about your heart rhythm or
symptoms, check with your doctor.
Arrhythmia Types:
Originating in the Atria
• Sinus arrhythmia. Cyclic changes in the heart
rate during breathing. Common in children and often found in adults.
• Sinus tachycardia. The sinus node sends out
electrical signals faster than usual, speeding up the heart rate.
• Sick sinus syndrome. The sinus node does not
fire its signals properly, so that the heart rate slows down. Sometimes the
rate changes back and forth between a slow (bradycardia) and fast
(tachycardia) rate.
• Premature supraventricular contractions or premature
atrial contractions (PAC). A beat occurs early in the atria, causing
the heart to beat before the next regular heartbeat.
• Supraventricular tachycardia (SVT), paroxysmal atrial
tachycardia (PAT). A series of early beats in the atria speed up the
heart rate (the number of times a heart beats per minute). In paroxysmal
tachycardia, repeated periods of very fast heartbeats begin and end suddenly.
• Atrial flutter. Rapidly fired signals cause the
muscles in the atria to contract quickly, leading to a very fast, steady
heartbeat.
• Atrial fibrillation. Electrical signals in the
atria are fired in a very fast and uncontrolled manner. Electrical signals
arrive in the ventricles in a completely irregular fashion, so the heart beat
is completely irregular.
• Wolff-Parkinson-White syndrome. Abnormal
pathways between the atria and ventricles cause the electrical signal to
arrive at the ventricles too soon and to be transmitted back into the atria.
Very fast heart rates may develop as the electrical signal ricochets between
the atria and ventricles.
Originating in the Ventricles
• Premature ventricular complexes (PVC). An
electrical signal from the ventricles causes an early heart beat that
generally goes unnoticed. The heart then seems to pause until the next beat of
the ventricle occurs in a regular fashion.
• Ventricular tachycardia. The heart beats fast
due to electrical signals arising from the ventricles (rather than from the
atria).
• Ventricular fibrillation. Electrical signals in
the ventricles are fired in a very fast and uncontrolled manner, causing the
heart to quiver rather than beat and pump blood.
What happens in the heart during an arrhythmia?
Describing how the heart beats normally helps to explain what happens during
an arrhythmia. The heart is a muscular pump divided into four chambers--two
atria located on the top and two ventricles located on the bottom. Normally
each heartbeat starts in the right atrium. Here, a specialized group of cells
called the sinus node, or natural pacemaker, sends an electrical signal. The
signal spreads throughout the atria to the area between the atria called the
atrioventricular (AV) node.
The AV node connects to a group of special pathways that conduct the signal to
the ventricles below. As the signal travels through the heart, the heart
contracts. First the atria contract, pumping blood into the ventricles. A
fraction of a second later, the ventricles contract, sending blood throughout
the body.
Usually the whole heart contracts between 60 and 100 times per minute. Each
contraction equals one heartbeat.
An arrhythmia may occur for one of several reasons:
• Instead of beginning in the sinus node, the heartbeat begins in another part
of the heart.
• The sinus node develops an abnormal rate or rhythm.
• A patient has a heart block.
What is a heart block?
Heart block is a condition in which the electrical signal cannot travel
normally down the special pathways to the ventricles. For example, the signal
from the atria to the ventricle may be (1) delayed, but each one conducted;
(2) delayed with only some getting through; or (3) completely interrupted. If
there is no conduction, the beat generally originates from the ventricles and
is very slow.
What are the different types of an arrhythmias?
There are many types of arrhythmias. Arrhythmias are identified by where they
occur in the heart (atria or ventricles) and by what happens to the heart's
rhythm when they occur. Arrhythmias arising in the atria are called atrial or
supraventricular (above the ventricles) arrhythmias. Ventricular arrhythmias
begin in the ventricles. In general, ventricular arrhythmias caused by heart
disease are the most serious.
How does the doctor know that I have arrhythmia?
Sometimes an arrhythmia can be detected by listening to the heart with a
stethoscope. However, the electrocardiogram is the most precise method for
diagnosing the arrhythmia. An arrhythmia may not occur at the time of the exam
even though symptoms are present at other times. In such cases, tests will be
done if necessary to find out whether an arrhythmia is causing the symptoms.
What tests can be done?
First the doctor will take a medical history and do a thorough physical exam.
Then one or more tests may be used to check for an arrhythmia and to decide
whether it is caused by heart disease.
Tests for Detecting Arrhythmias
• Electrocardiogram (ECG or EKG). A record of the
electrical activity of the heart. Disks are placed on the chest and connected
by wires to a recording machine. The heart's electrical signals cause a pen to
draw lines across a strip of graph paper in the ECG machine. The doctor
studies the shapes of these lines to check for any changes in the normal
rhythm. The types of ECGs are:
o Resting ECG. The patient lies down for a few
minutes while a record is made. In this type of ECG, disks are attached to the
patient's arms and legs as well as to the chest.
o Exercise ECG (stress test). The patient
exercises either on a treadmill machine or bicycle while connected to the ECG
machine. This test tells whether exercise causes arrhythmias or makes them
worse or whether there is evidence of inadequate blood flow to the heart
muscle ("ischemia").
o 24-hour ECG (Holter) monitoring. The patient
goes about his or her usual daily activities while wearing a small, portable
tape recorder that connects to the disks on the patient's chest. Over time,
this test shows changes in rhythm (or "ischemia") that may not be detected
during a resting or exercise ECG.( if you have arrhythmias and they never seem
to happen when the doctor is listening or an EKG is preformed INSIST on this
test or the next one below it...I did and they finally seen all the ones I was
having..)
o Transtelephonic monitoring. The patient wears
the tape recorder and disks over a period of a few days to several weeks. When
the patient feels an arrhythmia, he or she telephones a monitoring station
where the record is made. If access to a telephone is not possible, the
patient has the option of activating the monitor's memory function. Later,
when a telephone is accessible, the patient can transmit the recorded
information from the memory to the monitoring station. Transtelephonic
monitoring can reveal arrhythmias that occur only once every few days or
weeks.(this is also the other one I had which is wonderful to have
done...INSIST)
• Electrophysiologic study (EPS). A test for
arrhythmias that involves cardiac catheterization. Very thin, flexible tubes
(catheters) are placed in a vein of an arm or leg and advanced to the right
atrium and ventricle. This procedure allows doctors to find the site and type
of arrhythmia and how it responds to treatment.
How are arrhythmias treated?
Many arrhythmias require no treatment whatsoever. Serious arrhythmias are
treated in several ways depending on what is causing the arrhythmia. Sometimes
the heart disease is treated to control the arrhythmia. Or, the arrhthmia
itself may be treated using one or more of the following treatments.
• Drugs: There are several kinds of drugs used to
treat arrhythmias. One or more drugs may be used. Drugs are carefully chosen
because they can cause side effects. In some cases, they can cause arrhythmias
or make arrhythmias worse. For this reason, the benefits of the drug are
carefully weighed against any risks associated with taking it. It is important
not to change the dose or type of your medication unless you check with your
doctor first. If you are taking drugs for an arrhythmia, one of the following
tests will probably be used to see whether treatment is working: a 24-hour
electrocardiogram (ECG) while you are on drug therapy, an exercise ECG, or a
special technique to see how easily the arrhythmia can be caused. Blood levels
of antiarrhythmic drugs may also be checked.
• Cardioversion: To quickly restore a heart to
its normal rhythm, the doctor may apply an electrical shock to the chest wall.
Called cardioversion, this treatment is most often used in emergency
situations. After cardioversion, drugs are usually prescribed to prevent the
arrhythmia from recurring.
• Automatic implantable defibrillators: These
devices are used to correct serious ventricular arrhythmias that can lead to
sudden death. The defibrillator is surgically placed inside the patient's
chest. There, it monitors the heart's rhythm and quickly identifies serious
arrhythmias. With an electrical shock, it immediately disrupts a deadly
arrhythmia.
• Artificial pacemaker: An artificial pacemaker
can take charge of sending electrical signals to make the heart beat if the
heart's natural pacemaker is not working properly or its electrical pathway is
blocked. During a simple operation, this electrical device is placed under the
skin. A lead extends from the device to the right side of the heart, where it
is permanently anchored.
• Surgery: When an arrhythmia cannot be
controlled by other treatments,
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"Medical Terms"
That can be useful to
know...:-)
Ablation: The removal or destruction of tissue.
Advance Directive (living will): A document written
in "good" health which informs your family and health care providers of your
wishes for extended medical treatment in times of emergency.
Aerobic Exercise: Exercise which can improve your
functional ability and, in some cases, reduce symptoms of heart disease. It is
repetitive in nature and involves the large muscle groups. Examples are walking,
swimming, and cycling.
Ambulatory Monitors: Small portable
electrocardiograph machines that are able to record the heart's rhythm. Each
type of monitor has unique features related to length of recording time and
ability to send the recordings over the phone. They include: Holter Monitor,
Loop Recorder, and Transtelephonic transmitter.
Anemia: A condition characterized by a deficiency
of red blood cells. Anemia reduces the amount of oxygen available to the body.
Aneurysm: A sac formed by the bulging of a blood
vessel wall or heart tissue. When aneurysms grow too large, they can rupture and
the bleeding can be life threatening. In cardiac surgery, aneurysms usually
apply either to the ascending, aortic arch, or descending aorta. Aneurysms that
have grown too large should be replaced.
Angina (also called angina pectoris): Discomfort or
pressure, usually in the chest, caused by a temporarily inadequate blood supply
to the heart muscle. Discomfort may also be felt in the neck, jaw or arms.
Angiogenesis: The spontaneous or drug-induced
growth of new blood vessels. The growth of these vessels may help to alleviate
coronary artery disease by rerouting blood flow around clogged arteries.
Angioplasty: An invasive procedure, during which a
specially designed balloon catheter with a small balloon tip is guided to the
point of narrowing in the artery. Once in place, the balloon is inflated to
compress the fatty matter into the artery wall and stretch the artery open to
increase blood flow to the heart.
Angiotensin-Converting Enzyme Inhibitors (ACE
inhibitors): A group of drugs used to treat high blood pressure and heart
failure. ACE inhibitors block a specific enzyme (ACE or angiotensin-converting
enzyme) that retains salt in the kidney and can cause heart and blood pressure
problems. ACE inhibitors have been shown to decrease the risk of dying from a
heart attack.
Angiotensin II Receptor Blockers (ARBs): A group of
drugs used to treat high blood pressure.
Annulus: A ring of tough fibrous tissue that is
attached to and supports the leaflets of the heart valve.
Anomalous Coronary Artery: The normal anatomy for
the coronary arteries involves their origin from the aorta at each of two
separate sites. Sometimes people can be born with the origin of a coronary
artery that comes from an abnormal site and this can lead to problems of
coronary ischemia which can subsequently lead to a heart attack. Not all
coronary anomalies need surgery, but some do and the specific operation depends
on which of the many varieties of coronary anomalies is present.
Antiarrhythmic: A drug that is used to treat
abnormal heart rhythms.
Anticoagulant ("blood thinner"): A medication that
prevents blood from clotting; used for people at risk for stroke or blood clots.
Antihypertensive: A medication used to treat high
blood pressure.
Antioxidant: Vitamins (A, B, C and E) that may help
to limit the cellular damage caused by free radicals (which are released when
tissue is being injured, such as during the progression of heart disease.)
Studies suggest that certain antioxidants may protect against coronary artery
disease.
Aorta: Large artery leaving the heart. All blood
pumped out of the left ventricle travels through the aorta on its way to other
parts of the body.
Aortic Insufficiency : Aortic insufficiency refers
specifically to the aortic valve, which is the valve the blood passes through as
it leaves the heart and enters the aorta. When blood leaks back through the
valve it is known as aortic insufficiency. Small amounts of aortic insufficiency
may be inconsequential, but larger amounts require repair or replacement of the
aortic valve.
Aortic Valve: The aortic valve is the last valve
through which the blood passes before it enters the aorta or main blood vessel
of the body. The valve prevents blood from leaking back into the left ventricle
from the aorta after it has been ejected from the heart.
Aortic Valve Replacement : When the aortic valve is
diseased, it can become either stenotic (too narrow) or insufficient (leaky)
