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RESEARCHRIVERA

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PULSE
In medicine, one's pulse represents the tactile arterial palpation of the heartbeat by trained
fingertips. The pulse may be palpated in any place that allows an artery to be compressed against
a bone, such as at the neck (carotid artery), at the wrist (radial artery), behind the knee (popliteal
artery), on the inside of the elbow (brachial artery), and near the ankle joint (posterior tibial
artery). The pulse can also be measured by listening to the heart beat directly (auscultation),
traditionally using a stethoscope.
In Physiology, the pulse is a decidedly low tech/high yield and antiquated term still useful at the
bedside in an age of computational analysis of cardiac performance. Claudius Galen was perhaps
the first physiologist to describe the pulse. The pulse is an expedient tactile method of
determination of systolic blood pressure to a trained observer. Diastolic blood pressure is non-
palpable and unobservable by tactile methods, occurring between heartbeats.
Pressure waves generated by the heart in systole moves the arterial walls. Forward movement of
blood occurs when the boundaries are pliable and compliant. These properties form enough to
create a palpable pressure wave.
The heart rate may be greater or lesser than the pulse rate depending upon physiologic demand.
In this case, the heart rate is determined by auscultation or audible sounds at the heart apex, in
which case it is not the pulse. The pulse deficit (difference between heart beats and pulsations at
the periphery) is determined by simultaneous palpation at the radial artery and auscultation at the
heart apex.

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Pulse velocity, pulse deficits and much more physiologic data are readily and simplistically
visualized by the use of one or more arterial catheters connected to a transducer and oscilloscope.
This invasive technique has been commonly used in intensive care since the 1970s.
The rate of the pulse is observed and measured by tactile or visual means on the outside of an
artery and is recorded as beats per minute or BPM.
The pulse may be further indirectly observed under light absorbance of varying wavelengths
with assigned and inexpensively reproduced mathematical ratios. Applied capture of variances of
light signal from the blood component hemoglobin under oxygenated versus deoxygenated
conditions allows the technology of pulse oximetry.
NORMAL PULSE RATE
Normal pulse rates at rest, in beats per minute (BPM):
Table 1
Newborn
(03 months)
Infants
(36 months)
Infants
(612 months)
Children
(110 years)
Children over
10 years and
Adults,
including
seniors
Well
trained
adult
athletes
100 - 150 90120 80120 70 - 130 60 - 100 40 - 60
The pulse rate can be used to check overall heart health and fitness level. Generally lower is
better, but bradycardias can be dangerous. Symptoms of a dangerously slow heartbeat include
weakness, loss of energy and fainting.

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NORMAL BODY PULSE RATE
Pulse rates vary from individual to individual depending on factors such as fitness. Your
pulse, simply put, is the number times your heart beats in one minute. It will go up during
exercise and come down when you are resting. Knowing your pulse rate is important. A variation
in your pulse rate can signal a health condition.
The significance, a pulse rate can be useful for determining your fitness level and your
overall health. A quick pulse rate may indicate that you are dehydrated. If your resting heart rate
is usually above 100 beats per minute, this is called tachycardia, and it can indicate a health
problem. A bounding or strong and forceful pulse can come along with a rapid pulse rate, or can
occur separately. A bounding pulse can indicate that there is a fluid overload in the circulation,
or it can occur with high blood pressure. You should seek medical attention if you have a pulse
rate increase that's persistent, sudden or severe, advises the National Institutes of Health.
But warning when a person has an unusually slow heart rate--below 60 beats per minute--
and it's not due to a high fitness level, this is called bradycardia. This becomes a problem if the
heart doesn't pump enough oxygen-rich blood to a person's body, advises the Mayo Clinic.
People who have this condition may also feel faint, dizzy, weak confused or short of breath.
People with bradycardia sometimes need pacemakers.
A normal pulse rate varies depending on a person's age. The normal range for children
older than 10 and adults of all ages is 60 to 100 beats per minute. Athletes have a normal range
of 40 to 60 beats per minute. Kids ages 1 to 10 have a regular rate of 70 to 120 beats in a minute.
Infants have the fastest normal pulse rates, at 100 to 160 beats per minute, according to the NIH.

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The pulse may be measured at several points on the body where an artery is close to the
skin. These include the wrist, back of the knees, neck, temple, groin and the top or inner side of a
person's foot. When you find the pulse, count your beats for one minute. You also can count
beats for 30 seconds and then multiply by two or count beats for 10 seconds and multiply by six
to get your beats per minute. A person needs to rest for a minimum of 10 minutes before
measuring a resting heart rate. The heart rate for exercising may be taken during the activity.
NORMAL RANGE OF A HUMAN PULSE RATE
Your pulse signals how fast your heart is pumping. The pulse is taken to ensure the heart
is functioning properly and is also used as an indicator of general health. The normal pulse rate
varies depending on age, but most adults should be between 60 and 100 beats per minute.
A pulse is the number of times an individual's heart beats per minute. It is also known as
the heart rate. The pulse can be taken at any point on the body where an artery passes close to the
skin. These include the groin, temple, and top of the foot and back of the knee. However, the
easiest and most common spots are the wrist and neck. To properly measure the pulse, place two
fingers on one of these areas and count the beats for 30 seconds, then double that number. For a
proper reading of your resting pulse rate, 10 minutes of rest is required prior to measuring.
The normal range is Healthy resting pulse rates vary by age group. Newborn infants
should have a range of between 100 and 160 beats per minute and children ages 1 to 10 should
have a resting pulse between 70 and 120. Children over 10 and adults should have a resting pulse
range between 60 and 100 beats per minute. Maximal heart rates can also vary, even among
adults. To find your maximal heart rate, subtract your age from the number 220. Using this rule-
of-thumb calculation, if you are 35, your maximal heart rate is approximately 185.

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An individual's pulse rate is a good indicator of his overall health. A divergence either
above or below the recommended range can be a factor or symptom of a medical condition. In
serious and critical emergencies, pulse rates indicate that the heart is still working and pumping
blood through the body. High pulses can indicate an infection or dehydration. Athletes can use
pulse rates as a tool after exercise, the lower your heart rate the more physically fit you are.
Poor Pulse Rates
A high pulse, known as tachycardia, and a low pulse, known as bradycardia, may be
signs of a health problem. If you are suffering from either of these conditions, you should consult
your physcians. Irregular heart beat and a pulse that is very firm and lasts for several minutes
should also be discussed. If it is hard to feel your pulse, it may indicate that the arteries are
blocked. This is common in patients with diabetes and atherosclerosis.
NORMAL PULSE RATE FOR WOMEN
Pulse, or heart rate, is one way to objectively assess a woman's fitness level. Resting
heart rate reflects a baseline level of fitness, and pulse during exercise reveals the capacity that
your heart has to increase its performance. For an adult woman, an average pulse is between 60
and 100 beats per minute. The actual pulse depends on many factors, however, which is why the
normal range is so large.
Heart rate is one measurement of physical fitness. A single measurement can be
misleading, however, because individual heart rates vary greatly among women. Therefore, you
should measure your pulse on a regular basis, both at rest and during exercise, to know what

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your personal baseline is. Measuring heart rate recovery, or the speed at which your pulse returns
to resting rate after exercise, is another objective measure of fitness.
Depending on a woman's age, the normal 60 to 100 beats per minute changes. Female
infants have a normal pulse range of 100 to 160 beats per minute, whereas female children
between the ages of 1 and 10 have a normal range of 70 to 120 beats per minute, according to
Medline Plus. Female athletes typically have lower pulses than the normal range, and adult
athletes may have a rate as low as 30 beats per minute. Resting heart rate is your pulse when you
are completely at rest, ideally taken after you have been sitting quietly for at least 15 minutes.
Resting heart rate is in contrast to your heart rate during exercise, which can approach your
maximum heart rate. A good rule of thumb for your maximal heart rate is 220 minus your age.
Therefore, a woman aged 50 years has a predicted maximal heart rate of 170 beats per minute.
Warning, Normal heart rates and predicted maximal heart rates are not perfect standards
for comparison with your pulse. You should take your heart rate on a regular basis during both
rest and exercise, to determine whether your pulse is changing in any significant way over time.
If it does, you should consult your physician to identify the potential reasons that your pulse is
changing.
Potentially, by consistently measuring youre resting, maximal and recovery heart rates,
you can gain an objective and rather accurate assessment of your cardiovascular health. You
should strive to maintain a heart rate just below your maximal heart rate during exercise. Over
time, you will see that your resting heart rate will begin to decrease, as will your recovery time
from exercise to resting pulse. These measurements would indicate that you are improving your
overall fitness.

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CAUSES OF CHANGES OF HEART RATE
According to MayoClinic.com, a normal heart rate is between 60 and 100 beats per
minute. It is not uncommon for an athlete to have a resting heart rate between 40 to 60 beats per
minute. A low resting heart rate may be indicative of a healthy cardiovascular system or it may
signal the advent of heart disease. When the heart rate is over 100, it can be indicative of
strenuous activity or illness.
In order to keep adequate oxygenation of the muscles when working out, the heart has to
beat faster. As the intensity of exercise increases, the respiratory rate increases to bring more
oxygen into the system and the heart beats faster in order to transport that oxygen.
MayoClinic.com recommends that people not exceed a moderate intensity workout that keeps
the heart rate in between 75 and 80 percent of its maximum rate, which contributes to good heart
health.
Systemic illness can increase the heart rate. Fever increase the body's metabolism as it
tries to fight off the disease. Increased metabolism requires increased oxygenation and nutrients,
requiring the heart to beat faster. Fever also causes fluid loss through sweating, which is the
body's natural way of eliminating excess heat. The heart pumps faster when the body is
dehydrated. Drinking plenty of non-alcoholic liquids and using acetaminophen to bring the fever
down can help lower the heart rate.
MayoClinic.com states that other factors influence heart rate. Body size has a direct
effect on heart rate. The more weight the body has to carry around, the harder the heart has to
work to oxygenate the system. Emotions and stress can influence the heart rate. Stressful
situations turn on the fight or flight system in the brain, and this increases the heart rate. A

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meditative, peaceful state of mind can slow the heart rate. Air temperature, medications and body
position can also influence heart rate.
FOUR FACTORS THAT CAN CHANGE THE HEART RATE
The human heart is an amazing muscle that pumps oxygenated blood to every cell and
part of the body every second, minute and hour of the day. It never rests, but it can go through a
variety of changes, increasing its pace under certain circumstances. Knowing what's normal and
what's not helps individuals listen to their heart and their body and seek a doctor's advice if
something doesn't seem quite right. Multiple factors may affect the heart rate of any individual,
regardless of age, size or weight.
Exercise causes exertion, which makes the muscles work harder. When the muscles work
harder, they need more oxygen and nutrients for energy, which triggers the heart to beat faster to
supply these things. Depending on a person's physical fitness, her heart rate may rise only a little
or a lot. The human heart can beat more than 200 times per minute for those engaging in intense
activities or exercise. If you feel lightheaded, out of breath or ill when exercising, or if you feel
your heart is beating too rapidly, you may need to slow down and rest while the heart returns to a
more normal beat. Talking to your doctor will help you determine your maximum safe heart rate.
The American Heart Association suggests keeping within 50 to 80 percent of your maximum
heart rate.

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FACTORS THAT AFFECT HEART RATE
A person's heart rate is an effective indication of how healthy they are. Typical heart
rates, according to MayoClinic.com, are between 60 and 100 beats per minute at a resting rate. A
heart rate on the lower end of the range usually indicates a greater degree of cardiac efficiency
and health. There are many factors that affect heart rate.
Outside Temperature
High temperatures can increase heart rates, according to Dr. Pete Pfitzinger, a physician
and former runner who has extensively studied the physiology of human performance. When the
temperature jumps to 75 from 60 degrees F, a person's heart rate will increase by two to four
beats per minute. If the temperature rises from 75 to 90 degrees F, heart rate will rise by about 10
beats per minute. High amounts of humidity also can increase heart rate up to 10 beats per
minute. Pfitzinger suggests not doing any high intensity training on extremely hot days, as the
mixture of heat and humidity, mixed with high amounts of training, can cause an unsafe increase
in heart rate that can cause a heart attack.
Dehydration
When the body suffers from a lack of water, the volume of blood inside decreases along
with the amount of blood pumped with every heart beat. For every 1 percent of body weight lost
from dehydration, the heart rate rises seven beats per minute. For example, if someone weighs
175 lbs. and loses 5.25 lbs. through dehydration, their heart rate will increase by 21 beats per
minutea dangerous amount. The best way to counterbalance the risks is to stay hydrated,
especially on hot days when physical activity is being performed.

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Time of Day
Heart rate also changes based on whether it is morning, afternoon or evening. According
to Pfitzinger, heart rate increases by an average of five to six beats per minute in the afternoon,
but can rise by up to 10 beats per minute. The heart rate will increase slightly between the
afternoon and evening as well.
This means that if someone trains regularly, it is best to train in the morning, when heart
rate is at its lowest. By doing this, they maximize the amount of cardiovascular exercise.
Other Factors
According to the MayoClinic.com, other factors that can influence someone's heart rate
include body position, body size, medication use, level of fitness, activity level and emotions.
Combinations of these factors can also cause the heart to beat faster or slower than average.

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TYPICAL HEART RATE DURING SLEEP
When you sleep, your heart rate works in a cyclical variation. This variation ranges from
a minimal heart rate of 63 bps to a maximum of 67 bps, according to a study by researchers at
the University of Cape Town in South Africa, and published in a 2003 issue of "Journal of Sports
Medicine." Physical fitness and well-being have yet to be determined as variables that influence
a significant change in heart rate cyclical variation.
Cyclical Variation of Heart Rate
Cyclical variation of heart rate describes an increase and decrease of your heart rate
stages. Some factors include sudden arousal, also called apneas, or hypopneas -- the suspension
of abnormal breathing and overly shallow breathing, respectively. It represents why you may
have repeated autonomic arousals, even when you sleep. However, the clinical significance of
these arousals in daytime sleepiness remains unknown.
Heart Rate Arousals
Heart rate arousals during sleep occur for several reasons; some cannot be explained. For
example, a change in your EEG levels, electric activity present along the scalp, can represent one
valid occurrence. There must be a specific amount of activity over a certain threshold for you to
have an arousal for "no apparent reason," according to a study published in a 2007 issue of
"Computers in Cardiology." When respiratory events leading to arousal occur, they cause a sharp
rise in your heart rate when you awaken. When you fall asleep once more, your heart returns to
normal, causing a new cycle to begin.
Training Status and Sleep
As you exercise regularly, you may notice a shift in your heart rate, which can lead to
your heart performing at an optimal level. The "Journal of Sports Medicine" study found that

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subjects, which self-reported physical activity and average sleep time, ranging from four to 12
hours per week, and 5.5 to nine per night, respectively, had minimal heart rates ranging between
36 to 65 bpm, and maximum heart rates varying between 82 to 116 bpm.
Heart Rate Pattern Findings
The "Computers in Cardiology" study concluded that an adult's cyclical variation of heart
rate is frequent and easily quantifiable. An average of 60 events occurred, with the average heart
rate increasing by 7 to 8 bpm, and the cyclical variation averaging 16 bpm. This finding suggests
there is periodic activity activating the autonomic nervous system during sleep.

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NORMAL HEART RATE WHILE SLEEPING
Normal sleep is an uninterrupted and unconscious resting time your body and mind need
for seven to eight hours out of every 24. Sleep slows and relaxes your heart and circulatory
system because your metabolic needs are lower. So predicting your normal sleeping heart rate
depends on your normal waking heart rate. And all your hours of sleep are not alike, either.
SLEEP ONSET
Dr. K. Krauchi, in a study reported in "Neuropsychopharmacology" (2001), detected an
average drop from 64 to 52 beats per minute, about 8 percent, by the end of his subjects' gradual
sleep onset. He also reported that the mere signaling of "lights out" to subjects started the drop.
Researchers at the Abramson Center for Medical Physics at Tel Aviv University in Isreal, in
2006, discovered that during sleep onset your body transitions between two different
physiological states. Nerves that slow your heart are activated during sleep onset and nerves that
speed your heart are suppressed.
Subtracting 8 percent from your awake-resting heart rate approximates the drop that will
begin at lights off and continue until you reach light, continuous sleep (stage 1).
Later Stages
Sleep progresses from stage 1 through stage 4--progressively deeper stages of physical
relaxation--which occupy about 80 percent of your sleep time. During this time your heart rate
continues at its lower rate and may slow a few percent more as relaxation deepens, metabolism
slows and your body temperature drops slightly. Differences in age (seniors have progressively
less stage 3 and 4 sleep), general physical condition, your metabolic response to your previous
day's work level and other factors prevent exact predictions of further heart rate decreases during
stage 1 through stage 4.

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Dreaming
Twenty percent of the night, someone watching you sleep will see rapid-eye-movements
(REM) under your sleeping eye lids--you're watching all the action fly by in your dreams. In
REM sleep, your nervous system transitions to another physiological control state. Your heart
rate and breathing are freed to vary widely and unpredictably and may even exceed waking
norms. There is no "normal" heart rate in REM sleep.
Normal sleep is a series of approximately 90-minute cycles from stage 1 through stage 4,
followed by REM, then back to stage 1. As a result, your heart rate changes frequently all night.
After a Heart Attack
After a heart attack--a myocardial infarction (MI)--a patient's heart responds differently
in sleep than before. It may not slow from its waking rates. According to Dr. Emilio Vanoli, in
the Cardiovascular Disease Section, at the University of Oklahoma, the nerves that slow your
heart are not activated during sleep onset, and the nerves that can speed your heart remain active.
As a result, loss of calming influences leave a patient's heart more vulnerable during sleep,
possibly explaining the higher incidence of heart attacks and death during sleep.
Sleep Apnea
Sleep apnea is a periodic upper airway closure (obstructive sleep apnea, OSA) or periodic
absence of nerve impulses to breathe (central sleep apnea, CSA), which can occur from five to
200 times an hour, most commonly during REM sleep, but possible in other stages, too. This
sometimes causes severe oxygen deprivation, circulatory changes and heart stress along with
changes in heart rates. The actual rate depends on factors such as previous MI, cardiac

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medications, continuous positive airway pressure therapy (CPAP) for OSA, oxygen
administration and many others. No "normal" sleeping heart rate can be predicted in sleep apnea
patients.
Does your heart rate increase when you dream?
If you are wondering whether your heart rate went up while you had that crazy dream last
night, the simple answer is yes. In fact, whether you have a good dream or a bad dream, your
heart and breathing rate always increase during a dream cycle. Your first dream cycle will
typically occur 70 to 90 minutes after you fall asleep, and you will have several throughout the
night.
Physical Changes
A heart rate change while you are asleep is a clear indicator that you've entered a dream
cycle. In fact, your heart rate, body temperature and breathing rate all speed up as you enter a
dream cycle, according to "Dreams," by Mary Herd Tull and Amy Ning. Your heart rate is likely
to vary throughout this cycle and may speed up as much as 35 percent for short periods.
Dream Cycles
Dreaming seems to take lots of energy, note Tull and Ning, because your body goes into
another deep rest after each dream you have during the night. As the night goes on, each dream
cycle and its subsequent physiological changes, such as a higher heart rate, lasts longer. Your
first dream is likely to last eight to nine minutes, whereas your last dream can be an hour long.
You are likely to have a total dream time of about two hours if you sleep for eight. If your dream
cycle sleep is disrupted, however, your body won't follow the normal sleep cycle progression the
next time you sleep. Instead, you may go directly into a dream cycle and have extended dream

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cycle periods until you "catch up" on this stage of sleep, according to the National Institute of
Neurological Disorders and Stroke.
Mental Condition
Your state of mind as well as your physical condition can affect your heart rate. This may
be true even as you dream, says M. F. Madigan Jr., lead author of a study published in the
journal "Perceptual and Motor Skills." In his study, Madigan found that angry Type-A men have
greater heart-rate increases during their dream cycles than non-angry Type-B men.
Measuring
You can measure how much your heart rate changes during sleep with a heart rate
monitor. Monitoring your heart rate may provide enough information to show what your
breathing and sleep stages are throughout the night. In the past, sleep studies have used
electrodes connected to a person's head and torso to monitor muscle activity, brain waves and
eye movement along with heart rate. New information from the American Institute of Physics,
however, theorizes that heart rate monitoring is all that is really needed. The newer sleep analysis
method uses a mathematical technique to analyze synchronization between heartbeat and
breathing. This technique may even provide a measure of cardio-respiratory fitness, which may
be useful for athletes who want to optimize their workout routines and as a tool for choosing
treatments for people with cardiac diseases, notes PsychCentral.com.

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HEART RATE VARIABILITY DURING SLEEP
Sleep to get the rest you need every night, but rest assured, your heart does not sleep. It
slows down, a state called bradycardia, for part of the night, but may speed up, too. Your heart
stays on alert, varying its rate for your body's changing needs in different sleep stages.
Physicians at the Mayo Clinic define bradycardia as a heart rate under 50 beats per minute.
Trained athletes and normal sleepers may safely drop that low.
Falling Asleep
When you lie down to sleep, your heart takes a break from pumping blood uphill from
your feet, and from your heart to your head. Your body also uses less energy for balance and
movement, slowing to meet lower energy demands. Your mind also sends a slow-down message
to your heart. In 2001, Dr. Kurt Krauchi, reporting in "Neuropsychopharmacology," observed
that heart rates in sleep-study subjects started to drop at the moment of a "lights out" signal.
Overall, heart rate declines by about 8 percent from normal of about 72 beats per minute during
sleep onset.
Dreaming
You dream for about one-fifth to one-fourth of a normal night's sleep, a stage called
rapid-eye-movement, or REM sleep, even if you don't remember it when you wake up. Your
heart is released from its usual neurological and physiological controls during this time, and its
rate varies unpredictably over a wide range above and below normal. The rate may vary because
of the emotional content in your dreams.

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Non-REM Sleep
When you are not dreaming, during sleep stages 1 through 4, about 75 to 80 percent of
normal sleep, your heart is under more direct nervous and metabolic control than in REM sleep.
Your heart stays near its sleep-onset, 8 percent lower rate. But relaxation and neurological
controls lower your body temperature during deepest sleep. Your heart rate may decrease by a
few percent more. Sleep shifts through 90-minute cycles of stage 1 through 4 and REM all night.
Your heart rate varies all night, and is also influenced by your physical conditioning and the kind
of work you did all day.
Heart Disease
An injured heart does not respond in normal ways to sleep signals from your brain.
Reporting in a 1995 edition of the journal "Circulation," a research team at the University of
Oklahoma described heart rate changes they observed in sleeping patients after a heart attack.
The normal slow-down signal transmitted through the vagus nerve became ineffective, allowing
higher and more variable heart rates in sleep, unlike with normal subjects.
Sleep Disorders
If you use a continuous positive airway pressure, or CPAP, machine for obstructive sleep
apnea, your heart rate is subject to other than normal influences. Some CPAP machines are
prescribed with extra oxygen. This relieves your heart from speeding up in response to low
oxygen levels. If your sleep apnea is only partially controlled, or you remove your mask during
the night, your airway may re-obstruct as many as 200 times per hour, sending your heart rate to
emergency high levels. With sleep apnea, your heart rate is highly variable.

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Bradycardia
A slow heart rate of 60 beats per minute or less is called bradycardia. It can be caused by
problems with the heart's sinus node or problems with the electrical pathways in the heart. The
condition results in a lack of blood flow to the brain, so symptoms include dizziness and fainting.
Treatment options are limited. Doctors may implant a pacemaker to increase the heart rate. It's
risky because it can lead to heart failure and high blood pressure.
When to Seek Help
You may not have an irregular heart beat just because your heart is beating faster or
slower. It's normal for the heart to speed up during exercise and to slow down when you're
resting. It's not normal, however, when you have additional symptoms such as dizziness or
nausea. In those cases, you should seek attention from your doctor as soon as possible. If you are
concerned about heart attack, call 911 or go to the emergency room.

22/25
ABNORMAL HEART RATE
Heart rate is controlled by electrical impulses sent throughout the heart muscle.
Disruption to the electrical conduction system can alter the rate at which the heart beats.
Tachycardia and bradycardia are abnormal heart rates.
Normal Heart Rate
The electrical impulse that generates a heart beat originates at the sinoatrial node, located
in the right atrium. This node consists of the heart's pacemaker cells. These cells initiate a
heartbeat at a rate of approximately 60 to 100 beats per minute when a person is at rest.
Bradycardia
Bradycardia occurs when the heart is unable to maintain a resting rate of at least 60 beats
per minute. The heart's major function is to deliver oxygen and nutrients throughout the body. A
slow heart rate limits this delivery capability and reduces oxygen transport. Because the body,
and especially the brain, relies on a constant supply of oxygen for proper functioning, the Mayo
Clinic says bradycardia can cause many symptoms. Dizziness, faintness, fatigue, shortness of
breath and chest pain can all result from a slow heart rate. Bradycardia is common in aging
people, those with known heart disease, and in people on certain medications, such as beta-
blockers. In these people, the bradycardia is considered a pathological complication, meaning it
results from a disease state, and therefore requires treatment. However, some people incur
bradycardia due to the positive adaptation of the heart to exercise training. This type of
bradycardia is termed physiological. Physiological bradycardia enhances oxygen delivery and
indicates the heart has become a more efficient, stronger pump.

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Tachycardia
The term tachycardia refers to a resting heart rate greater than 100 beats per minute.
Tachycardia is identified at rest, because an elevated heart rate is a normal response to exercise.
Tachycardia causes a quivering of muscle in the atria or the ventricles rather than a strong,
synchronized contraction. This quivering reduces the amount of blood ejected from each
chamber per beat. The quivering associated with atrial tachycardia reduces the amount of blood
sent to the ventricles, and could potentially stimulate the ventricles into a fast rhythm.
Ventricular tachycardia is potentially fatal. It can rapidly progress to sudden cardiac arrest. If the
ventricles quiver rather than contract uniformly, they're unable to deliver oxygen-rich blood to
the body. The lack of oxygen causes cells to die off, including those of the heart muscle, and
sudden cardiac arrest ensues.
Diagnosis
According to the text "ECG Interpretation for the Clinical Exercise Physiologist," the
electrocardiogram (ECG) is the initial diagnostic tool used to identify bradycardia and
tachycardia. In the event that a person doesn't have an abnormal heart rate at all times, a portable
ECG is applied to the person, and heart rate recordings are monitored over a period of days.
Additional testing to identify the cause, specific triggers and severity of the abnormal rhythm
might be necessary. These can include tilt table testing, exercise stress testing and
electrophysiological testing.
Treatment
In 2008, the American College of Cardiology published guidelines for the use of
pacemakers in patients with bradycardia. The pacemaker prevents the heart rate from dropping

24/25
below a designated lower limit by taking over the job of the pacemaker cells if they fail to
maintain the necessary rate for adequate oxygen delivery. The same guidelines indicate the use
of a defibrillator for tachycardia patients. Defibrillators deliver an electrical shock that jolts a fast
heart rate back to normal. It's used in the prevention of sudden cardiac arrest.

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REFERENCES:
http://en.wikipedia.org/wiki/Pulse http://www.livestrong.com/article/91011-normal-body-pulse-rate/#ixzz2FqEi3xat http://www.livestrong.com/article/139640-causes-changes-heart-rate/ http://www.livestrong.com/article/379519-typical-heart-rate-during-sleep/ http://www.livestrong.com/article/105256-normal-heart-rate-sleeping/
http://www.livestrong.com/article/91011-normal-body-pulse-rate/#ixzz2FqEi3xathttp://www.livestrong.com/article/91011-normal-body-pulse-rate/#ixzz2FqEi3xat

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