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PRINCIPLES OF THE ELECTROCARDIOGRAM
PROCEDURE AND INTERPRETATION BASIC ELECTROCARDIOGRAPHY
JASSIN M. JOURIA, MD Dr. Jassin M. Jouria is a practicing Emergency Medicine physician, professor of academic medicine, and medical author. He graduated from Ross University School of Medicine and has completed his clinical clerkship training in various teaching hospitals throughout New York, including King’s County Hospital Center and Brookdale Medical Center, among others. Dr. Jouria has passed all USMLE medical board exams, and has served as a test prep tutor and instructor for Kaplan. He has developed several medical courses and curricula for a variety of educational institutions. Dr. Jouria has also served on multiple levels in the academic field including faculty member and Department Chair. Dr. Jouria continues to serve as a Subject Matter Expert for several continuing education organizations covering multiple basic medical sciences. He has also developed several continuing medical education courses covering various topics in clinical medicine. Recently, Dr. Jouria has been contracted by the University of Miami/Jackson Memorial Hospital’s Department of Surgery to develop an e-module training series for trauma patient management. Dr. Jouria is currently authoring an academic textbook on Human Anatomy & Physiology. ABSTRACT
Electrocardiograms are valuable tests for evaluating heart health and to
diagnose cardiac issues. But the test is only as good as the skill of the
clinician performing it. Medical clinicians must commit to learning and
updating their electrocardiogram procedure and interpretation skills to arrive
at a correct diagnosis, and these skills start with an understanding of the
basic function of the electrocardiogram. Being able to identify normal
readings on an electrocardiogram rhythm strip is the first step to recognizing
cardiac issues, and possibly saving lives.
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Policy Statement
This activity has been planned and implemented in accordance with the
policies of NurseCe4Less.com and the continuing nursing education
requirements of the American Nurses Credentialing Center's Commission on
Accreditation for registered nurses. It is the policy of NurseCe4Less.com to
ensure objectivity, transparency, and best practice in clinical education for
all continuing nursing education (CNE) activities.
Continuing Education Credit Designation
This educational activity is credited for 3 hours. Nurses may only claim credit
commensurate with the credit awarded for completion of this course activity.
Statement of Learning Need
Health clinicians in general practice and cardiology need to be able to
understand the function and information generated by an electrocardiogram.
The correct diagnosis and proper treatment of a cardiac condition is
dependent on competent and accurate interpretation of diagnostic tests,
which includes the electrocardiogram in both inpatient and outpatient
settings.
Course Purpose
To provide health clinicians with basic knowledge about the purpose,
function and diagnostic data of an electrocardiogram.
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Target Audience
Advanced Practice Registered Nurses and Registered Nurses
(Interdisciplinary Health Team Members, including Vocational Nurses and
Medical Assistants may obtain a Certificate of Completion)
Course Author & Planning Team Conflict of Interest Disclosures
Jassin M. Jouria, MD, William S. Cook, PhD, Douglas Lawrence, MA
Susan DePasquale, MSN, FPMHNP-BC – all have no disclosures
Acknowledgement of Commercial Support
There is no commercial support for this course.
Please take time to complete a self-assessment of knowledge, on page 4, sample questions before reading the article.
Opportunity to complete a self-assessment of knowledge learned will be provided at the end of the course.
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1. An electrocardiogram (ECG) is best described as
a. a heart blood pressure monitor. b. a pacemaker. c. a recording of the electrical activity of the heart. d. electrodes that mimic the bundle of His.
2. True or False: The rhythm strip output provides a clinician with a
“snapshot” of the heart’s activity at a moment in time.
a. True b. False
3. With the rhythm strip the placement of electrodes for the limb
and augmented voltage leads
a. are the same for all ECGs so the graphs may be compared. b. depends on the polarization of the cardiac cells. c. are different for a resting ECG compared to an exercising ECG. d. depends on the size of the electrical fields.
4. In a normal situation, depolarization of cardiac cells begins in
a. the atrioventricular node. b. the atria. c. the ventricles. d. the sinus node.
5. These electrical signals spread through the heart as wave fronts
of
a. depolarization. b. polarization. c. augmentation. d. electrical fields.
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Introduction
An electrocardiogram is a recording of the electrical activity of the heart. It
measures the electrical waves and impulses of the heart using 10 or 12
electrodes, which are placed on specific areas of the chest, arms, and legs
and are connected to wires. The electrodes pick up heart impulses and sends
them through the wires to produce a graph of the heart’s electrical
conductivity. This allows a clinician to diagnose a patient’s heart rate and
rhythm by analyzing an electrocardiogram rhythm strip using the triplet’s
method and the six second method. By identifying the classification system
of cardiac rhythms, the clinician is able to differentiate between the types of
rhythms, know how to identify a pacemaker rhythm, explain the relationship
between P wave and the QRS complex, and identify common causes of
dysrhythmia.
The 12-Lead Electrocardiogram
The 12-lead electrocardiogram is the standard diagnostic test a clinician will
use to view the electrical activity of a patient’s heart. The 12-lead
electrocardiogram records this activity from electrodes on the body surface.
The term “lead” is used in two ways: it refers to the wire that connects to
two or more electrodes, and it refers to the view of the electrical activity of
the heart from a certain angle of the body as seen on electrocardiogram
paper.4,94
Rhythm Strip Output
The rhythm strip output is different than a 12-lead electrocardiogram (ECG)
output in that a rhythm strip records the same leads (views of heart activity)
across the entire ECG paper. The placement of electrodes for the limb and
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augmented voltage leads are slightly different depending on whether the
ECG is a resting or exercising one.
A rhythm strip is a more precise method of detecting a problem on what is
an otherwise normal ECG. An ECG is like a snapshot of the heart’s activity at
a moment in time, while the rhythm strip is a continuous feed.
Rhythm Analysis
When analyzing a cardiac rhythm, it is critical that medical clinicians
recognize what the cardiac complex represents and what is considered
normal and abnormal. It is also important that clinicians practice cardiac
rhythm analysis. The more practice in rhythm analysis, the more
comfortable a clinician will be with the processes involved and all aspects of
interpretation.
The technique and interpretation of cardiac rhythms can be a combination of
science and art. When interpreting an ECG, a clinician is analyzing a graphic
record of the electrical activity of the heart.94 Each cardiac cell generates an
action potential. This is as it becomes depolarized and then repolarized
during a normal cycle. In a normal situation, depolarization of cardiac cells
proceeds in an orderly fashion. This begins in the sinus node. It then spreads
sequentially through the atria, atrioventricular node, and ventricles. These
electrical signals spread through the heart as wave fronts of depolarization.
The wave fronts result in minute electrical fields. These fields allow detection
at the body’s surface, which clinicians record as the activation and recovery
signals of working myocardial cells.2
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An electrocardiograph may have a default setting to trace each lead for 2.5
seconds. Longer settings of 6 or 10 seconds may be used to identify a
pattern in the heart’s rhythm.
Timing across an ECG report page is continuous. Needles trace each lead on
paper. Each row represents ECG lead activity as the paper is pulled under
the needle. A lead is the source of measurement of a vector. For the limb
leads, they are the comparison between two electrodes. For the precordial
leads, they are compared to a common lead.58 There are three sets of leads;
the limb, augmented limb, and precordial leads. The 12-lead ECG uses three
limb leads and three augmented limb leads that are arranged in a frontal
plane. Six chest (precordial) leads are used to view the heart from the
transverse or horizontal plane.
In the ECG, two leads are called contiguous if they reflect neighboring
anatomical areas. A lead is a connector to an electrode, which is a
conductive pad in contact with the body. It makes an electrical circuit with
the electrocardiograph. Leads can share the same electrode. A standard 12-
lead ECG needs only 10 electrodes. The 10 electrodes in a 12-lead ECG are
applied to the body as described below, and are identified as RA, LA, RL, LL,
V1, V2, V3, V4, V5, and V6. With each of the 12 ECG leads, there is a
recording of cardiac electrical activity from a different angle and anatomical
area of the heart. These differing orientations or views are described
below.95
Bipolar limb leads (frontal plane)
Lead I: RA (right arm) (-) to LA (left arm) (+) (Right Left, or lateral)
Lead II: RA (-) to LL (left foot) (+) (Superior Inferior)
Lead III: LA (-) to LL (+) (Superior Inferior)
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Augmented unipolar limb leads (frontal plane)
Lead aVR (augmented vector right): RA (+) to [LA & LL] (-) (Rightward)
Lead aVL (augmented vector left): LA (+) to [RA & LL] (-) (Leftward)
Lead aVF (augmented vector foot): LL (+) to [RA & LA] (-) (Inferior)
Unipolar (+) chest leads (transverse or horizontal plane)
Leads V1, V2, V3: (Posterior Anterior)
Leads V4, V5, V6:(Right Left, or lateral)
12-Lead ECG Placements
When placing the leads, the following locations and rules apply:
• RA (right arm): avoid thick muscle
• LA (left arm): avoid thick muscle
• RL (right leg): placed at the lower end of the medial aspect of the calf
muscle, avoiding the bony prominences
• LL (left leg): placed at the lower end of the medial aspect of the calf,
avoiding the bony prominences
• V1: placed at the fourth intercostal space between ribs 4 and 5, just to
the right of the sternum breastbone
• V2: placed at the fourth intercostal space between ribs 4 and 5, just to
the left of the sternum
• V3: placed between leads V2 and V4
• V4: placed at the fifth intercostal space between ribs 5 and 6 and in the
mid clavicular line
• V5: placed horizontally even with V4 in the left anterior axillary line
• V6: placed horizontally even with V4 and V5 in the mid axillary line
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ECG Rhythm Strip Report
A normal heart beats when electrical impulses spread through the cardiac
atria (upper chambers) to the cardiac ventricles (lower chambers), in an
organized and sequential manner. When analyzing an ECG tracing, the
clinician must first check R wave to R wave across the strip. If the intervals
vary by 1.5 small boxes or less, the heart rhythm can be considered regular.
When taking a person’s pulse, and repeating the pulse in 10 minutes, the
heart rate can be expected to be the same number. Several factors work
together to maintain the body’s homeostasis, and R wave to R wave analysis
refers to the normal rhythmicity of the cardiac ventricles; and, when
measuring P wave to P wave this refers to the rhythmicity of the atria.2
Several types of information can be determined from evaluating the cardiac
rhythm through an ECG, which indicates normal or abnormal conditions. An
abnormal heart rhythm, referred to as an arrhythmia or dysrhythmia, is an
abnormally slow or fast heart rate, or an irregular cardiac rhythm.
Arrhythmia and dysrhythmia are words used to describe the same condition
in a different way; the word arrhythmia describes a condition in which a
person does not have a regular heart rhythm, whereas dysrhythmia refers to
an abnormal rhythm, so these terms mean the same thing.
The ECG waveform has a number of indicators for each heartbeat. These
indicators are the P, Q, R, S, T, and U waveforms. The first movement of the
ECG tracing is usually an upward deflection and is the P wave. This indicates
electrical activity that triggers atrial contraction. The components of QRS
mark ventricular depolarization and contraction. They are usually of greater
amplitude than the P wave. The T wave is normally a waveform that has an
upward deflection and smaller than the QRS. This indicates ventricular
repolarization.
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A cardiac rhythm strip can provide information on essential dysrhythmia
categories. These include 1) atrial (premature atrial contractions, atrial
flutter, atrial fibrillation, multifocal atrial tachycardia, wandering atrial
pacemaker), 2) junctional (junctional tachycardia, premature junctional
contraction), 3) ventricular (supraventricular tachycardia, premature
ventricular contractions, accelerated idioventricular rhythm, ventricular
fibrillation, monomorphic ventricular tachycardia, polymorphic ventricular
tachycardia), 4) heart blocks (first degree heart block, second degree heart
block, third degree heart block), and 5) sudden arrhythmic death syndrome.
Second degree heart block can also include type 1 (mobitz I) and type 2
(mobitz II).2
Triplets Method Technique
The Triplets method heart rate technique is a quick estimate of the heart
rate. This technique gives the clinician an idea of the arrhythmia to be
interpreted; by example, for the heart rate, the beats per minute is found by
counting with the 0 and using the R wave deflection directly on top of a dark
line of a large box.
The math basis for the Triplets technique involves 1500 small boxes in one
minute. Taking the number of boxes, the clinician divides 1500 by the
number of boxes. If there are 5 small boxes, this is 1500/5 or 300 beats per
minute. The 1500 comes from 25 small boxes per second. The number of
small boxes per minute are determined with there being 60 seconds/minute
and by taking 25 x 60 = 1500 or 1500 small boxes per minute. The clinician
will estimate heart rate as 1500/6 small boxes or 250 beats per minute,
1500/7 small boxes or 214 beats per minute, or 1500/8 small boxes or 187
beats per minute.3
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Six Second Method of Rhythm Analysis
Using the 6-second method with an irregular rhythm to estimate a heart
rate, the number of R waves are counted in a 6-second strip and then
multiplied by 10. For example, if there are seven R waves in a 6-second
strip, the heart rate is 70, which is determined from 7x10=70. If there are
eight R waves in a 6-second strip, the heart rate is 8x10=80.4-8
Rhythm Classification Types
Considering the rhythm according to classification and types, classification
can be regular, regularly irregular, and irregularly irregular. Regular
classification refers to a normal heart rhythm or normal sinus rhythm (NSR)
for short. This normal sinus rhythm has a heart rate that is the same as the
pulse between 50 and 100 beats per minute. It also has a normal impulse
formation from the sinoatrial (SA) node (or P wave in the ECG).
Regularly irregular classification means the RR intervals or PP intervals
between beats are the same. With a sinus arrhythmia there is a cyclical
acceleration of the heart rate with inspiration and slowing with expiration.
The beat to beat interval is different. The rhythm is regularly irregular in that
there is a pattern to the irregularity.
Irregularly irregular classification means there is no pattern at all. All of the
intervals are haphazard. All of the intervals also do not repeat with an
accidental exception that is occasional. Irregularly irregular rhythms include
atrial fibrillation, wandering atrial pacemaker, and multifocal atrial
tachycardia.9
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Identifying ECG Rhythm Types
As mentioned, the classification system of rhythm refers to regular, regularly
irregular, or irregularly irregular. Rhythm is best analyzed when looking at a
rhythm strip. For a 12-lead ECG, this can be a 10-second recording from
lead II. The clinician should confirm or corroborate findings in lead II by
checking other leads. It can be helpful to look at a longer rhythm strip
recorded at a slower speed.9
Considering examples of broad complex tachycardia (BCT), a regular broad
complex tachycardia includes ventricular tachycardia, antidromic
atrioventricular re-entry tachycardia (AVRT) and any regular
supraventricular tachycardia with aberrant conduction; for example,
aberrant conduction may be due to bundle branch block and rate-related
aberrancy. Irregular broad complex tachycardia includes ventricular
fibrillation and polymorphic ventricular tachycardia, including torsades de
pointes. Also included are atrial fibrillation with Wolff-Parkinson-White
(WPW) syndrome (a condition in which there is an extra electrical pathway
in the heart) and any irregular supraventricular tachycardia with aberrant
condition. Again, an aberrant condition may be due to bundle branch block
and related aberrancy.63
Types of Cardiac Rhythms
To differentiate between the types of rhythms a medical clinician should first
consider the difference between rate and rhythm. In a normal heart, the
heart rate is the rate in which the sinoatrial node depolarizes as it is the
source of depolarization of the heart. As with other vital signs such as blood
pressure and respiratory rate, heart rate changes with age. In an adult, a
normal heart rate is between 60 and 100 beats per minute (normocardiac).
For a child, the heart rate will be higher.
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Bradycardia is less than 60 beats per minute in adults and involves a heart
rate less than normal. Tachycardia is higher than 100 in adults and is higher
than normal. If the atria and ventricles are not in synchrony, this is a
complication and the heart rate must be specified as atrial or ventricular. For
example, the atrial rate in atrial fibrillation is 300 to 600 bpm. A ventricular
rate can be normal at 60 to 100 bpm or faster at 100 to 150 bpm.
For a normal resting heart, the physiologic rhythm of the heart is normal
sinus rhythm (NSR). This normal sinus rhythm produces the prototypical
pattern of P wave, QRS complex, and T wave. The first step in interpreting a
rhythm strip or ECG is whether there is a sinus rhythm. A criterion for
evaluating sinus rhythm is that the P wave and QRS complex are 1 to 1,
implying that the P wave generates the QRS complex.
After establishing a sinus rhythm, the heart rate is next determined by
counting the (1 to 1) P waves and QRS complexes. If the rate is too fast, it
is a sinus tachycardia. If the rate is too slow, it is a sinus bradycardia. If it is
not a sinus rhythm, the clinician must determine the rhythm before
proceeding with additional interpretation.
Generally, a deviation from normal sinus rhythm is considered to be a
cardiac arrhythmia. Here are some arrhythmias with characteristic findings.
• Absent P waves and irregularly irregular QRS complexes are signs of
atrial fibrillation.
• A saw tooth pattern with QRS complexes is the sign of atrial flutter.
• A sine wave pattern is the indicator of ventricular flutter.
• Absent P waves with wide QRS complexes with fast rate are signs of
ventricular tachycardia.
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The clinician must make a determination of rate and rhythm to make further
interpretation possible. Remember that a sinus rhythm means a normal
heart beat with respect to the heart rate and rhythm. The heart rate will fall
between 60 and 100 beats per minute. The shape of the tracing on the
rhythm strip or ECG will show the key attributes needed to be considered
normal.
A sinus rhythm occurs with any cardiac rhythm that has depolarization of the
cardiac muscle beginning at the sinus node. It shows a correctly oriented P
wave on the rhythm strip or ECG. Sinus rhythm is needed but is not
sufficient for normal electrical activity in the heart.
Normal sinus rhythm is where all other measurements of the ECG fall in
designated normal limits and show the characteristic appearance of the ECG
when the electrical conduction system of the heart functions normally. Other
sinus rhythms can be normal in certain patient groups and clinical situations,
and include sinus tachycardia, sinus bradycardia, and sinus arrhythmia. A
sinus rhythm could be seen together with other cardiac arrhythmias on the
same ECG.10,11
The term sinus relates to or denotes the sinoatrial node of the heart or its
function as a pacemaker. The sinoatrial node is a small body of specialized
muscle tissue in the wall of the right atrium of the heart that acts as a
pacemaker by producing a contractile signal at regular intervals. This group
of cells located in the wall of the right atrium of the heart is the sinoatrial
node, also called SA node or sinus node.10
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Cardiac Rhythms
Types of cardiac rhythms are identified as sinus, atrial, supraventricular,
ventricular, premature ventricular contractions (PVC), Torsades de Pointes,
asystole, pulseless electrical activity (PEA), and artificial pacemaker. A sinus
rhythm is required for normal electrical activity of the heart however is not
entirely sufficient for normal cardiac electrical activity.
As mentioned above, arrhythmia is a term that means a heartbeat is
irregular. This does not mean the heart is beating too slowly or too fast. It
just means the heart is not functioning in a normal rhythm. A person can
feel that their heart has skipped a beat, added a beat, is fluttering, or is
beating too fast (tachycardia) or too slow (bradycardia). Some arrhythmias
are silent so the person is not aware of the condition.23
An arrhythmia can lead to a medical emergency. It can also be harmless. A
person can have an arrhythmia if the person’s heart is healthy or when heart
disease is present. Changes in the heart muscle, injury from a heart attack,
healing after heart surgery, or the wrong balance of electrolytes in the blood
including sodium or potassium can cause an arrhythmia.
Among the many types of arrhythmias, premature atrial contractions involve
early extra beats that start in the heart's upper chambers (atria), and are
considered harmless and typically need no treatment. Premature ventricular
contractions are among the most common arrhythmias and cause a skipped
heart beat type of feeling. They can be related to too much nicotine or
caffeine. Sometimes they can be caused by an electrolyte imbalance or heart
disease. If a patient has frequent premature ventricular contractions, a
cardiologist should be consulted.
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Atrial fibrillation is a common irregular heart rhythm that causes the upper
chambers of the heart to contract abnormally. Atrial flutter is an arrhythmia
that is usually more organized and regular than atrial fibrillation. This
happens often in a person with heart disease and shortly after heart surgery.
It can change into atrial fibrillation.
Paroxysmal supraventricular tachycardia is a rapid heart rate, usually with a
regular rhythm. It starts from above the heart's ventricles, and begins and
ends suddenly. With accessory pathway tachycardias, a patient can get a
rapid heart rate because there is an extra pathway between the heart's
upper and lower chambers. When this happens the impulses that control
heart rhythm travel quickly and cause the heart to beat unusually fast.
Sinus Rhythm
A sinus rhythm refers to any cardiac rhythm where depolarization of the
cardiac muscle begins at the sinus node. A correctly oriented P wave on the
electrocardiogram or rhythm strip is how a sinus rhythm is characterized.
This sinus rhythm is needed, but not entirely sufficient, for normal electrical
activity in the heart.
Normal sinus rhythm is where all measurements on an electrocardiogram fall
within designated normal limits. This gives rise to a characteristic
appearance on the electrocardiogram when the electrical conduction system
of the heart functions normally. As mentioned earlier, a sinus rhythm can
include a sinus tachycardia, sinus bradycardia, and sinus arrhythmia. A sinus
rhythm can present with other cardiac arrhythmias on the same
electrocardiogram or rhythm strip.64
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P Waves and QRS Complex
To briefly summarize, in a normal
rhythm strip there are three distinct
waves. The first is the P wave. This
represents depolarization of the atria
and happens before the atria contract
and push blood into the ventricles. The
next wave is called the QRS wave. The
third wave is the T wave. The P wave
can show right or left atrial
hypertrophy or atrial arrhythmias. It is
best determined in leads II and V1
during sinus rhythm. A normal P wave
is positive in II and AVF and biphasic
in V1.
The QRS complex is a name for the combination of three of the graphical
deflections as seen on a rhythm strip. It is usually the central and most
visually obvious part of the tracing on the rhythm strip. It corresponds to the
depolarization of the right and left ventricles of the heart. In an adult it
normally lasts 0.06–0.10 s, and in a child and during physical activity it
could be shorter.
The Q, R, and S waves occur in rapid succession. They do not appear in all
leads. They reflect a single event and are usually considered together. The Q
wave is any downward deflection after the P wave. An R wave follows as an
upward deflection. The S wave is any downward deflection after the R wave.
The T wave follows the S wave. In some cases, an additional U wave follows
the T wave.
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The P wave, representing atrial depolarization and preceding the QRS
complex, looks like a small bump up from the baseline. The amplitude for
the P wave is normally 0.05 to 0.25 mV. This is 0.5 to 2.5 small boxes.
Typical abnormalities for a P wave include a P mitrale (bifid P waves), seen
with left atrial enlargement. Another is P pulmonal (peaked P waves), seen
with right atrial enlargement. Another is P wave inversion, seen with ectopic
atrial and junctional rhythms.20
Atrial Rhythms
Atrial rhythms can include atrial fibrillation, atrial tachycardia, atrial flutter,
premature atrial contraction, and multifocal atrial tachycardia. Atrial
fibrillation, also known AF or A-fib, is an abnormal heart rhythm
characterized by rapid and irregular beating of the atria. Atrial tachycardia is
a type of heart rhythm problem in which the heart's electrical impulse comes
from an ectopic pacemaker. Atrial flutter (AFL), is a common abnormal heart
rhythm. It starts in the atrial chambers of the heart.
Premature atrial contractions (PACs), atrial premature complexes (APCs), or
atrial premature beats (APB) are a common cardiac dysrhythmia. Multifocal
atrial tachycardia is also known as a multiform atrial tachycardia (MAT),
which is an abnormal heart rhythm and a type of supraventricular
tachycardia.
Supraventricular Tachycardia
Supraventricular tachycardia (SVT) and a paroxysmal supraventricular
tachycardia (PSVT) is an abnormally fast heart rhythm arising from improper
electrical activity in the upper part of the heart. Paroxysmal supraventricular
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tachycardia is a type of supraventricular tachycardia. Someone with this
condition could have no symptoms.
Supraventricular tachycardia is also broadly defined as an abnormally fast
heartbeat. The problem originates supraventricular or in the atria or atrial
ventricular node.24 Tachycardia involves a heart rate that is greater than 100
beats per minute, and occurs when the electrical impulses coordinating heart
beats do not work properly. It can feel like a racing heart or fluttering. Many
who have a rare episode of supraventricular tachycardia can live a healthy
life with no restrictions or interventions. For some, treatment and lifestyle
changes can help to eliminate or control the rapid heartbeats of tachycardia.
Types of supraventricular tachycardia include atrial tachycardia and
atrioventricular nodal reentry tachycardia (AVNRT). Symptoms include a
supraventricular tachycardia that can come and go suddenly. There can be
stretches of normal heart rate in between. Symptoms can last for a few
minutes and can also last a few days. Some people with the condition have
no symptoms. If supraventricular tachycardia occurs frequently it can
become a problem. If it is ongoing it can be a problem if a patient has heart
damage or another coexisting medical condition or problem.
Signs and symptoms of supraventricular tachycardia can include palpitations
that are a rapid heartbeat, fluttering in the chest, shortness of breath,
lightheadedness, dizziness, sweating, a pounding sensation in the neck,
fainting known as syncope or near fainting. For a young child or an infant,
signs and symptoms can be difficult to identify. A child with a pulse rate of
over 200 beats a minute, poor feeding, and pale skin can indicate
supraventricular tachycardia.
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Ventricular Tachycardia
Ventricular tachycardia can also be called V-tach or VT and include a
catecholaminergic polymorphic ventricular tachycardia (CPVT) and familial
polymorphic ventricular tachycardia (FPVT). Ventricular tachycardia is a type
of regular and fast heart rate that arises from improper electrical activity in
the ventricles. Catecholaminergic polymorphic ventricular tachycardia can
also be called catecholamine-induced polymorphic ventricular tachycardia.25
Ventricular tachycardia is a heart rhythm disorder and arrhythmia that is
caused by abnormal electrical signals in the lower chambers of the heart
(ventricles). Electrical signals regulate the heart rate as the signals are sent
across heart tissues. The rate of a healthy heart normally is about 60 to 100
times a minute at rest. This is defined by signals that originate in the upper
atria.
In ventricular tachycardia, abnormal electrical signals in the ventricles cause
the heart to beat faster than normal. This is usually 100 or more beats a
minute and out of sync with the upper chambers. When this happens the
heart might not pump enough blood to the body and lungs. This is because
the chambers are beating fast and out of sync with each other. They do not
have time to properly fill.
Ventricular tachycardia can be brief. It can last for a few seconds and
possibly not cause symptoms. In some cases, it can last much longer. It can
cause symptoms such as dizziness, lightheadedness, and palpitations. It can
even cause a loss of consciousness. Ventricular tachycardia can also cause a
heart to stop with sudden cardiac arrest, a life-threatening, medical
emergency. The condition can occur when a person has another heart
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condition. For example, it could be a previous heart attack or other
structural heart disease, such as cardiomyopathy.
Ventricular fibrillation is a dangerous condition related to ventricular
tachycardia. With ventricular fibrillation the lower heart chambers contract in
a very rapid and uncoordinated way. At times this rhythm could result from
ventricular tachycardia that degenerates into ventricular fibrillation. Or it
could originate from single ventricular beats. Most often this abnormal
rhythm happens with established heart disease or a prior heart attack. It
could also occur due to an electrolyte abnormality or, rarely, even in what is
an otherwise normal heart. An electrolyte abnormality could be a high or low
potassium level. Ventricular fibrillation can also cause sudden cardiac arrest
and can lead to death if not treated immediately.65
Premature Ventricular Contractions
As previously mentioned, the heart is made up of four chambers - two upper
chambers (atria) and two lower chambers (ventricles) and the rhythm of the
heart is normally controlled by the sinus node. The sinus node is an area of
specialized cells located in the right atrium known as a natural pacemaker. It
produces electrical impulses and triggers the normal heartbeat. From the
sinoatrial node, electrical impulses travel across the atria to the ventricles.
This causes them to contract and pump blood to the lungs and body.11
Premature ventricular contractions are abnormal contractions that begin in
the ventricles. They are extra contractions that usually beat sooner than the
next expected regular heartbeat and often interrupt the normal order of
pumping from atria to the ventricles. What results is extra and out of sync
beats that is usually less effective at pumping blood throughout the
body.12,13
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Torsades de Pointes
Torsades de Pointes is also known as torsade de pointes, TdP, or torsade(s).
In translation from the French it means twisting of the points. It is a specific
type of abnormal heart rhythm and can lead to sudden cardiac death.
Torsades de Pointes is a polymorphic ventricular tachycardia and exhibits
distinct characteristics on an ECG or rhythm strip. Prolongation of the QT
interval can increase the risk a person has of developing this abnormal heart
rhythm.14-16
Asystole
Asystole is the absence of ventricular contractions that last longer than the
maximum time sustainable for life, which is about two seconds. Asystole is
the most serious form of cardiac arrest. It is usually irreversible.
A cardiac flat line, asystole, is the state of complete cessation of electrical
activity from the heart. This means no tissue contraction from the heart
muscle. It also means no blood flow to the rest of the body. As a state of
cardiac standstill, asystole involves no cardiac output. There is also no
ventricular depolarization. This occurs eventually in all dying patients. An
ECG rhythm strip confirms asystole.26
Bradyasystolic rhythms are slow rhythms. They can have a narrow or wide
complex with or without a pulse. They are often interspersed with periods of
asystole. Additionally, pulseless electrical activity (PEA) is a term that
applies to a group of dysrhythmias unaccompanied by a pulse that is
detectable. Concerning PEA, ventricular fibrillation and ventricular
tachycardia are excluded.26
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Asystole can be diagnosed as primary or secondary. With primary asystole
the heart’s electrical system intrinsically fails to generate a ventricular
depolarization. This can result from ischemia or degeneration as with
sclerosis of the sinoatrial node or atrioventricular conducting system.
Usually, primary asystole is preceded by a bradydysrhythmia due to sinus
node block-arrest, complete heart block, or both.
When there is ocular surgery, retrobulbar block, eye trauma, direct pressure
on the globe, maxillofacial surgery, hypersensitive carotid sinus syndrome,
or glossopharyngeal neuralgia, the result can be reflex bradyasystole or
asystole. There are reports of episodes of asystole and bradycardia as
manifestations of left temporal lobe complex partial seizures. Patients
experienced either fainting or dizziness. There were no reports of sudden
death, but it was possible for asystole to persist with the longest interval
being 26 seconds.27
With secondary asystole, factors outside of the heart's electrical conduction
system result in a failure to generate any electrical depolarization. The final
common pathway is usually severe tissue hypoxia with metabolic acidosis.
Ventricular fibrillation asystole or bradyasystole follows and typically occurs
after unsuccessful attempts at defibrillation.26
Cardiac Arrest
A result of idiopathic degeneration of the sinoatrial or atrioventricular node
can be sinus arrest-block and/or AV heart block, respectively. While this
process is progressive and slow, the symptoms can be acute and result in
asystole or cardiac arrest. What is required for these conditions is usually an
implantable pacemaker. Asystolic sudden death can occur from congenital
heart block, cardiac trauma, or local tumor.
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Primary and Secondary Asystole
When cellular metabolic functions are no longer intact and no electrical
impulse can be generated this is when primary asystole develops.
Implantable pacemaker failure can also be the cause of primary asystole.
Severe ischemia can create a situation where pacemaker cells cannot
transport the ions needed to affect the transmembrane action potential. With
proximal occlusion of the right coronary artery can come ischemia or
infarction of both the sinoatrial (SA) and the atrioventricular (AV) nodes.
With extensive infarction can come bilateral bundle-branch block, which is
infranodal complete heart block.
Secondary asystole can result from common conditions such as suffocation,
near drowning, massive pulmonary embolus, stroke, hyperkalemia,
hypothermia, myocardial infarction (MI) complicated by VF or VT that
deteriorates to asystole, post defibrillation, and sedative-hypnotic or narcotic
overdoses leading to respiratory failure. A special circumstance is
hypothermia. This is because asystole can be tolerated for a longer period
under such conditions and can be reversed with rapid rewarming while CPR
is being performed.26
Epidemiology of Asystole
It is difficult to measure accurately the number of adults in the U.S.,
identified with cardiopulmonary arrest who had bradyasystole as the initial
arrest rhythm. Reports vary plus could be skewed by the patient population
studied and/or by the method of reporting the initial rhythm. As an example,
a 1991 study reported on 185 patients in cardiopulmonary arrest at the time
of arrival to the emergency department. Of these patients, 9% had survived
to hospital admission but none were discharged alive. This study did not
report on patients with asystole only. In another Swedish study, asystole
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was the presenting rhythm in the field in 35% of patients with cardiac
arrest.
Race is not a factor in asystole except when related to underlying conditions
that can lead to cardiac arrest. This includes chronic hypertension, coronary
artery disease, renal failure, congestive heart failure, or cardiac
dysrhythmias. When a certain race of people has a relatively low incidence of
coronary artery disease, asystole is relatively more common as a
manifestation of cardiopulmonary arrests. In this case, cardiac ischemia
more frequently results in ventricular fibrillation.
Concerning the factor of age, the prevalence of asystole as the presenting
cardiac rhythm is lower in adults (25-56%) than in children (90-95%).
Asystole is most likely found in cardiopulmonary arrests occurring in
children. This is typically secondary to another non-cardiac event meaning
respiratory arrest due to sudden infant death syndrome, chocking,
infections, drowning, or poisoning. An infant is more statistically likely to
suffer a cardiac arrest compared to an older child or adolescent.
In the Resuscitation Outcomes Consortium Epistry-Cardiac Arrest trial, non-
traumatic cardiac arrest occurred at a rate of 72.1 per 100,000 infants. This
is versus 3.73 per 100,000 in children and 7.37 per 100,000 in adolescents.
Investigators found the adult rate of cardiac arrest was 126.52 per 100,000.
This is when they evaluated 25,405 adults and 624 patients younger than 20
years. Pediatric patients with ventricular fibrillation or ventricular tachycardia
were 4 times more likely to survive an out-of-hospital cardiac arrest (20%)
than those with asystole (5%). Patients younger than 20 years had an
overall better survival rate than adults when all rhythms are included and
traumatic arrests are excluded.
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Concerning gender, the frequency of asystole, as a percentage of all
cardiopulmonary arrests, is higher in women than in men. The frequency of
cardiac arrest in general is proportional to the underlying incidence of heart
disease, which is more common in males until around age 75 years.26
Prognosis
The prognosis for asystole depends on the cause of the asystolic rhythm,
timing of interventions, and failure or success of advanced cardiac life
support. Resuscitation will likely be successful if it is secondary to an event
that can be corrected immediately. This is in a case such as cardiac arrest
due to choking on food and only if an airway can be established and the
patient may be rapidly re-oxygenated. There are occasions where reversal of
primary asystole is possible if it is due to pacemaker failure, which could be
either intrinsic or extrinsic, and if this is corrected immediately by external
pacing.
In general, the prognosis for asystole is not good regardless of its cause.
Individuals with post-counter shock asystole have an especially poor survival
rate. In the Termination of Resuscitation study, when no shock was advised
in patients with unwitnessed cardiac arrest, there were no survivors. In the
Goteborg, Sweden study, 10% of 1,635 asystolic patients survived to
hospital admission; and, only 2% survived to hospital discharge.
According to the American Heart Association (AHA) guidelines to improve
cardiocerebral resuscitation, improved outcomes in all adults with out of
hospital cardiac arrest was evident for ventricular tachycardia and
ventricular fibrillation only. Complications from asystole include permanent
neurologic impairment. Complications can also be due to cardiopulmonary
resuscitation (CPR) or conditions such as liver laceration, fractured ribs,
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pneumothorax, hemothorax, aspiration, air embolus, and gastric/esophageal
rupture. It has been reported that death often occurs.26
Pulseless Electrical Activity
Pulseless electrical activity (PEA) or electromechanical dissociation involves
cardiac arrest where the electrocardiogram shows a heart rhythm that
should produce a pulse but does not. PEA is found at first in about 55
percent of people with cardiac arrest. In a normal circumstance electrical
activation of muscle cells precedes mechanical contraction of the heart. This
is known as electromechanical coupling. With PEA there is electrical activity,
however, the heart either does not contract or there is another reason this
results in an insufficient cardiac output to generate a pulse and supply blood
to the organs. This is classified as a form of cardiac arrest but significant
cardiac output can still be present. This may be determined and best seen
with a bedside ultrasound.28
Pulseless electrical activity is characterized by unresponsiveness and lack of
palpable pulse in the presence of organized cardiac electrical activity. A lack
of ventricular activity always implies a lack of ventricular mechanical activity
or asystole. The reverse is not always true as asystole does not always imply
a lack of ventricular activity. Electrical activity is a necessary but not
sufficient condition for mechanical activity. With cardiac arrest, organized
ventricular electrical activity is not necessarily accompanied by ventricular
mechanical activity that is meaningful. By meaningful ventricular activity,
this means a degree of mechanical activity that is sufficient to generate a
palpable pulse.
Pulseless electrical activity does not mean mechanical quiescence or cell
cycle arrest. A patient could have weak ventricular contractions plus a
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recordable aortic pressure or pseudo pulseless electrical activity. True
pulseless electrical activity refers to a condition where cardiac contractions
are absent and coordinated electrical activity is present. Pulseless electrical
activity can encompass a number of organized cardiac rhythms. These
include supraventricular rhythms as sinus versus non-sinus. They also
include ventricular rhythms as accelerated idioventricular or escape. An
absence of peripheral pulses is not necessarily indicative of pulseless
electrical activity. It could be due to severe peripheral vascular disease.28
Detecting a Heart Rhythm During PEA
Pulseless electrical activity (PEA) is evident on an ECG rhythm strip.
Pulseless electrical activity can also be known as electromechanical
dissociation. It refers to cardiac arrest in which the electrocardiogram shows
a heart rhythm that should produce a pulse, but does not. About half of
people in cardiac arrest are found initially with pulseless electrical activity.16
Normally, electrical activation of muscle cells precedes a mechanical
contraction of the heart. This is known as electromechanical coupling. With
PEA there is electrical activity. However, the heart either does not contract
or there is a reason this results in an insufficient cardiac output to generate
a pulse and supply blood to organs. Pulseless electrical activity is classified
as a type of cardiac arrest and significant cardiac output can still be present.
This can be determined and visualized best by a bedside ultrasound.16
The first treatment for PEA is cardiopulmonary resuscitation (CPR), which
commences while potential underlying causes are identified and treated.
Administration of medication, such as epinephrine, is possible. The rate of
survival is about twenty percent.16
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The condition of pulseless electrical activity leads to the loss of cardiac
output. In addition, the blood supply to the brain is interrupted. PEA is
usually observed when a person loses consciousness and stops
spontaneously breathing. Confirmation comes upon examining the airway for
obstruction plus observing the chest for respiratory movement plus feeling
the pulse usually at the carotid artery for a period of ten seconds.
Some in the medical community use a mnemonic to remember possible
causes. The mnemonic is six Hs and six Ts.
• Six Hs
1) Hypovolemia, 2) Hypoxia, 3) Hydrogen ions (Acidosis), 4) Hyper-
or Hypokalemia, 5) Hypoglycemia, and 6) Hypothermia.
• Six Ts
1) Tablets or Toxins (drug overdose), 2) Cardiac Tamponade,
3) Tension pneumothorax, 4) Thrombosis (for example, myocardial
infarction, pulmonary embolism), 5) Tachycardia, and 6) Trauma (for
example, hypovolemia from blood loss).
The above list is not comprehensive; for example, it does not include
anaphylaxis, but this list is a starting point. A clinical diagnosis of PEA can
also be connected to pressure effects associated with artificial ventilation
that can also contribute to significant reduction in cardiac output.
The possible mechanisms where conditions can cause pulseless in PEA are
those recognized as producing a circulatory shock state. These include
impairment of cardiac filling, impaired pumping effectiveness of the heart,
circulatory obstructions, and pathological vasodilation causing loss of
vascular resistance and excess capacitance. It is possible to have more than
one mechanism involved in a case.
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A clinical diagnosis of cardiac arrest is confirmed by the absence of a pulse.
However, distinguishing PEA from other causes of cardiac arrest can come
only with a device capable of electrocardiography. With PEA there is semi-
organized electrical activity in the heart in contrast to asystole (flatline) or to
disorganized electrical activity of ventricular fibrillation or ventricular
tachycardia.
Cardiopulmonary resuscitation should be initiated promptly to maintain
cardiac output until there is correction of the PEA. This is what ACLS/BCLS
cardiac resuscitation guidelines advise. In treating PEA, the approach is to
treat the underlying cause as known. For example, this could include
relieving a tension pneumothorax. When there is not a determination of the
underlying cause for the PEA or it cannot be reversed, treatment of pulseless
electrical activity can be similar to the treatment for asystole.
External cardiac compression may not increase cardiac output for any
situations involving PEA. This includes hemorrhage where impairment of
cardiac filling is the underlying mechanism that produces the loss of a pulse
that is detectable.
Medications should be provided through an intravenous or intraosseous line.
Drug therapy for PEA can include epinephrine 1 mg every 3-5 minutes. The
AHA in 2010 withdrew the recommendation of what was previously used
with atropine in the treatment of PEA/asystole. This was due to lack of
evidence for therapeutic benefit. Not recommended also is the routine use of
sodium bicarbonate except with special situations such as a preexisting
metabolic acidosis, hyperkalemia, or tricyclic antidepressant overdose. Any
administered drugs should go along with cardiopulmonary resuscitation
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techniques. A cardiac defibrillator cannot correct this rhythm because the
problem lies in the response of technocardial tissue to electrical impulses.
Summary
An electrocardiogram is a recording of the electrical activity of the heart.
This allows a clinician to diagnose a patient’s heart rates and palpitations,
arrhythmia or dysrhythmia.
Several types of information can be determined from evaluating the cardiac
rhythm through an ECG, which indicates normal or abnormal cardiac
conditions. The classification system of cardiac rhythm refers to regular,
regularly irregular, or irregularly irregular. Cardiac rhythm is best analyzed
when looking at an ECG rhythm strip. An ECG is like a snapshot of the
heart’s activity at a moment in time, while the rhythm strip is a continuous
feed. Clinicians caring for cardiac patients should be able to analyze an
electrocardiogram rhythm strip using validated methods and they should
also be able to identify the classification system of cardiac rhythms, be able
to differentiate between the types of rhythms and know how to identify a
pacemaker rhythm as well as serious ventricular rhythms.
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1. An electrocardiogram (ECG) is best described as
a. a heart blood pressure monitor. b. a pacemaker. c. a recording of the electrical activity of the heart. d. electrodes that mimic the bundle of His.
2. True or False: The rhythm strip output provides a clinician with a
“snapshot” of the heart’s activity at a moment in time.
a. True b. False
3. With the rhythm strip the placement of electrodes for the limb
and augmented voltage leads
a. are the same for all ECGs so the graphs may be compared. b. depends on the polarization of the cardiac cells. c. are different for a resting ECG compared to an exercising ECG. d. depends on the size of the electrical fields.
4. In a normal situation, depolarization of cardiac cells begins in
a. the atrioventricular node. b. the atria. c. the ventricles. d. the sinus node.
5. These electrical signals spread through the heart as wave fronts
of
a. depolarization. b. polarization. c. augmentation. d. electrical fields.
6. An electrocardiograph may have a default setting to trace each
lead for
a. 2.5 seconds. b. 10 seconds. c. a minute of tracing. d. 12 heartbeats.
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7. True or False. Pulseless electrical activity is characterized by unresponsiveness and lack of palpable pulse in the presence of disorganized cardiac electrical activity.
a. True b. False
8. In the ECG, two leads are called _______________ leads if they
reflect neighboring anatomical areas.
a. split b. contiguous c. simultaneous d. remote
9. The 12-lead ECG uses ______ chest (precordial) leads.
a. two b. ten c. six d. four
10. True or False: When placing leads for a 12-Lead ECG, the RA
(right arm) lead should be placed on the right arm over an area with thick muscle.
a. True b. False
11. Which of the following transverse leads is placed at the fourth
intercostal space between ribs 4 and 5, just to the right of the sternum breastbone?
a. V1 b. V2 c. V4 d. V5
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12. Using the 6-second method with an irregular rhythm to estimate a heart rate, if there are seven R waves in a 6-second strip, the heart rate is
a. 60 (6-seconds x 10) b. 52 ((6 x 7) + 10) c. 130 ((6+7) 10) d. 70 (7 x 10)
13. When analyzing an ECG tracing, the clinician must first check
_______________________ across the strip.
a. P wave to P wave b. the QRS components c. R wave to R wave d. the T wave
14. The sinus node is an area of specialized cells located in the right
atrium known as
a. a natural pacemaker. b. the QRS components. c. the repolarization center. d. a natural electrocardiogram.
15. Which of the indictors of the ECG waveform indicates ventricular
repolarization?
a. The R wave b. The QRS components c. The P wave d. The T wave
16. Regularly irregular classification means the RR interval or PP
interval between beats
a. have no pattern. b. are the same. c. are haphazard. d. are different.
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17. Regular classification refers to a normal heart rhythm or normal sinus rhythm that is the same as the ________ between 50 and 100 beats per minute.
a. P wave b. impulse c. pulse d. rhythm
18. True or False: An arrhythmia refers to a rapid, abnormal heart
rhythm, whereas a dysrhythmia is a condition of an irregularly slow heart rhythm.
a. True b. False
19. With a 12-lead ECG, rhythm is best analyzed when looking at a
10-second rhythm strip recording from lead II and the clinician should confirm or corroborate findings in lead II
a. by rechecking lead II. b. by looking at an ECG snapshot. c. by checking the patient’s pulse. d. by checking other leads.
20. Wolff-Parkinson-White (WPW) syndrome is a condition in which
there is
a. a bundle branch block. b. an irregularly irregular rhythm. c. a wandering atrial pacemaker. d. an extra electrical pathway in the heart.
21. After establishing a sinus rhythm, the heart rate is determined
and if the heart rate is too fast, the patient has
a. a sinus tachycardia. b. Wolff-Parkinson-White (WPW) syndrome. c. a sinus bradycardia. d. an irregularly irregular rhythm.
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22. True or False: As with other vital signs such as blood pressure and respiratory rate, heart rate changes with age.
a. True b. False
23. A person can have an arrhythmia
a. only if the person has heart disease. b. only if the person has a heart injury or disease. c. if the person’s heart is healthy. d. None of the above
24. Paroxysmal supraventricular tachycardia is a rapid heart rate,
usually with
a. a regularly irregular rhythm. b. Wolff-Parkinson-White (WPW) syndrome. c. a regular rhythm. d. an irregularly irregular rhythm.
25. Electromechanical dissociation involves cardiac arrest where the
electrocardiogram shows a heart rhythm
a. a is regularly irregular. b. that is regular. c. that should produce a pulse but does not. d. that should not produce a pulse but does.
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CORRECT ANSWERS: 1. An electrocardiogram (ECG) is best described as
c. a recording of the electrical activity of the heart. “An electrocardiogram (ECG or EKG) is a recording of the electrical activity of the heart.”
2. True or False: The rhythm strip output provides a clinician with a
“snapshot” of the heart’s activity at a moment in time.
b. False “The rhythm strip output is different than a 12-lead ECG output in that a rhythm strip records the same leads (views of heart activity) across the entire ECG paper..... An ECG is like a snapshot of the heart’s activity at a moment in time, while the rhythm strip is a continuous feed.”
3. With the rhythm strip the placement of electrodes for the limb
and augmented voltage leads
c. are different for a resting ECG compared to an exercising ECG. “The rhythm strip output is different than a 12-lead ECG output in that a rhythm strip records the same leads (views of heart activity) across the entire ECG paper. The placement of electrodes for the limb and augmented voltage leads are slightly different depending on whether the ECG is a resting or exercising one.”
4. In a normal situation, depolarization of cardiac cells begins in
d. the sinus node. “In a normal situation, depolarization of cardiac cells proceeds in an orderly fashion. This begins in the sinus node. It then spreads sequentially through the atria, atrioventricular node, and ventricles.”
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5. These electrical signals spread through the heart as wave fronts of
a. depolarization. “These electrical signals spread through the heart as wave fronts of depolarization. The wave fronts result in minute electrical fields.”
6. An electrocardiograph may have a default setting to trace each
lead for
a. 2.5 seconds. “An electrocardiograph may have a default setting to trace each lead for 2.5 seconds. Longer settings of 6 or 10 seconds may be used to identify a pattern in the heart’s rhythm.”
7. True or False. Pulseless electrical activity is characterized by
unresponsiveness and lack of palpable pulse in the presence of disorganized cardiac electrical activity.
b. False. “Pulseless electrical activity is characterized by unresponsiveness and lack of palpable pulse in the presence of organized cardiac electrical activity.”
8. In the ECG, two leads are called _______________ leads if they
reflect neighboring anatomical areas.
b. contiguous “In the ECG, two leads are called contiguous if they reflect neighboring anatomical areas.”
9. The 12-lead ECG uses ______ chest (precordial) leads.
c. six “The 12-lead ECG uses three limb leads and three augmented limb leads that are arranged in a frontal plane. Six chest (precordial) leads are used to view the heart from the transverse or horizontal plane.”
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10. True or False: When placing leads for a 12-Lead ECG, the RA (right arm) lead should be placed on the right arm over an area with thick muscle.
b. False “When placing the leads, the following locations and rules apply: RA (right arm): avoid thick muscle; LA (left arm): avoid thick muscle; RL (right leg): placed at the lower end of the medial aspect of the calf muscle, avoiding the bony prominences.”
11. Which of the following transverse leads is placed at the fourth
intercostal space between ribs 4 and 5, just to the right of the sternum breastbone?
a. V1 “When placing the leads, the following locations and rules apply: ... V1: placed at the fourth intercostal space between ribs 4 and 5, just to the right of the sternum breastbone.”
12. Using the 6-second method with an irregular rhythm to estimate
a heart rate, if there are seven R waves in a 6-second strip, the heart rate is
d. 70 (7 x 10) “Using the 6-second method with an irregular rhythm to estimate a heart rate, the number of R waves are counted in a 6-second strip and then multiplied by 10. For example, if there are seven R waves in a 6-second strip, the heart rate is 70, which is determined from 7x10=70. If there are eight R waves in a 6-second strip, the heart rate is 8x10=80.”
13. When analyzing an ECG tracing, the clinician must first check
_______________________ across the strip.
c. R wave to R wave “When analyzing an ECG tracing, the clinician must first check R wave to R wave across the strip.”
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14. The sinus node is an area of specialized cells located in the right atrium known as
a. a natural pacemaker. “The sinus node is an area of specialized cells located in the right atrium known as a natural pacemaker.”
15. Which of the indictors of the ECG waveform indicates ventricular
repolarization?
d. The T wave “The T wave is normally a waveform that has an upward deflection and smaller than the QRS. This indicates ventricular repolarization.”
16. Regularly irregular classification means the RR interval or PP
interval between beats
b. are the same. “Regularly irregular classification means the RR intervals or PP intervals between beats are the same. With a sinus arrhythmia there is a cyclical acceleration of the heart rate with inspiration and slowing with expiration. The beat to beat interval is different. The rhythm is regularly irregular in that there is a pattern to the irregularity.”
17. Regular classification refers to a normal heart rhythm or normal
sinus rhythm that is the same as the ________ between 50 and 100 beats per minute.
c. pulse “Regular classification refers to a normal heart rhythm or normal sinus rhythm (NSR) for short. This normal sinus rhythm has a heart rate that is the same as the pulse between 50 and 100 beats per minute. It also has a normal impulse formation from the sinoatrial (SA) node (or P wave in the ECG).”
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18. True or False: An arrhythmia refers to a rapid, abnormal heart rhythm, whereas a dysrhythmia is a condition of an irregularly slow heart rhythm.
b. False “An abnormal heart rhythm, referred to as an arrhythmia or dysrhythmia, is an abnormally slow or fast heart rate, or an irregular cardiac rhythm. Arrhythmia and dysrhythmia are words used to describe this same condition but in a different way: the word arrhythmia describes a condition in which a person does not have a regular heart rhythm, whereas dysrhythmia refers to an abnormal rhythm, so these terms mean the same thing.”
19. With a 12-lead ECG, rhythm is best analyzed when looking at a
10-second rhythm strip recording from lead II and the clinician should confirm or corroborate findings in lead II
d. by checking other leads. “Rhythm is best analyzed when looking at a rhythm strip. For a 12-lead ECG, this can be a 10 second recording from lead II. The clinician should confirm or corroborate findings in lead II by checking other leads. It can be helpful to look at a longer rhythm strip recorded at a slower speed.”
20. Wolff-Parkinson-White (WPW) syndrome is a condition in which
there is
d. an extra electrical pathway in the heart. “Irregular broad complex tachycardia includes ventricular fibrillation and polymorphic ventricular tachycardia, including torsades de pointes. Also included are atrial fibrillation with Wolff-Parkinson-White (WPW) syndrome (a condition in which there is an extra electrical pathway in the heart) and any irregular supraventricular tachycardia with aberrant condition.”
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21. After establishing a sinus rhythm, the heart rate is determined and if the heart rate is too fast, the patient has
a. a sinus tachycardia. “After establishing a sinus rhythm, the heart rate is next determined by counting the (1 to 1) P waves and QRS complexes. If the rate is too fast, it is a sinus tachycardia. If the rate is too slow, it is a sinus bradycardia.”
22. True or False: As with other vital signs such as blood pressure
and respiratory rate, heart rate changes with age.
a. True “As with other vital signs such as blood pressure and respiratory rate, heart rate changes with age.”
23. A person can have an arrhythmia
c. if the person’s heart is healthy. “An arrhythmia can lead to a medical emergency. It can also be harmless. A person can have an arrhythmia if the person’s heart is healthy or when heart disease is present. Changes in the heart muscle, injury from a heart attack, healing after heart surgery, or the wrong balance of electrolytes in the blood including sodium or potassium can cause an arrhythmia.”
24. Paroxysmal supraventricular tachycardia is a rapid heart rate,
usually with
c. a regular rhythm. “Paroxysmal supraventricular tachycardia is a rapid heart rate, usually with a regular rhythm.”
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25. Electromechanical dissociation involves cardiac arrest where the electrocardiogram shows a heart rhythm
c. that should produce a pulse but does not. “Pulseless electrical activity (PEA) or electromechanical dissociation involves cardiac arrest where the electrocardiogram shows a heart rhythm that should produce a pulse but does not.”
Reference Section The References below include published works and in-text citations of published works that are intended as helpful material for your further reading. [These References are for a multi-part series on Basic Electrocardiography]. 1. Prutkin, J.M. (2017). ECG tutorial: Basic principles of ECG analysis.
UpToDate. Retrieved online at https://www.uptodate.com/contents/ecg-tutorial-basic-principles-of-ecg-analysis?source=search_result&search=electrocardiogram&selectedTitle=1~150.
2. O’Brien, T. (2016). Introduction to cardiac rhythm strip analysis. EKG.Academy. Retrieved online at https://ekg.academy/learn-ekg?courseid=318&seq=1
3. Tso, Colin, et al (2015). Electrocardiography: A Technologist’s Guide to Interpretation. Journal of Nuclear Medicine Technology. Vol. 43 no. 4 247-252.
4. Prutkin, J. (2017). ECG tutorial: Electrical components of the ECG. UpToDate. Retrieved online at https://www.uptodate.com/contents/ecg-tutorial-electrical-components-of-the-ecg?soure=search_result&search=6+second+method+ECG+rhythm+strip&selectedTitle=4~150
5. Goldberger, A. (2016). Basic principles of electrocardiographic interpretation. UpToDate. Retrieved online at https://www.uptodate.com/contents/basic-principles-of-electrocardiographic-interpretation?source=see_link
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6. Goldberger, A., et al (2017). Goldberger's Clinical Electrocardiography: A Simplified Approach, 9th ed; Retrieved from Elsevier, Philadelphia.
7. Mirvis, D.M. and Goldberger, A. (2014). Electrocardiography. In: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 10th ed, Bonow, RO, Mann, DL, Zipes, DP, Libby, P (Eds), W.B. Saunders Company, Philadelphia
8. Sauer, W.H. (2017). Left bundle branch block. UpToDate. Retrieved online at https://www.uptodate.com/contents/left-bundle-branch-block?source=see_link
9. Jones & Barlett Learning. (n.d.). Rhythms. Retrieved online at http://samples.jbpub.com/9780763712846/12841_CH08_Garcia.pdf
10. Hampton, John R (2013). The ECG Made Easy (8th ed.). Retrieved from Edinburgh: Churchill Livingstone. p. 4. ISBN 9780702046421.
11. Mayo Clinic (2014). Premature ventricular contractions. Retrieved online at http://www.mayoclinic.org/diseases-conditions/premature-ventricular-contractions/basics/causes/con-20030205
12. Manolis, A. (2017). Supraventricular premature beats. Retrieved online at https://www.uptodate.com/contents/supraventricular-premature-beats?source=search_result&search=premature+ventral+contraction&selectedTitle=2~150
13. Conen, D., et al. (2012). Premature atrial contractions in the general population: frequency and risk factors. Circulation 126:2302.
14. Prutkin, J. (2015). ECG tutorial: Ventricular arrhythmias. UpToDate. Retrieved online at https://www.uptodate.com/contents/ecg-tutorial-ventricular-arrhythmias?source=search_result&search=torsades+de+pointes&selectedTitle=5~150
15. Seslar, S.P., et. al. (2014). Clinical features of congenital long QT syndrome. UpToDate. Retrieved online at https://www.uptodate.com/contents/clinical-features-of-congenital-long-qt-syndrome?source=search_result&search=torsades+de+pointes&selectedTitle=3~145
16. Baldzizhar, A., et al. (2016). Ventricular Tachycardias: Characteristics and Management. Critical care nursing clinics of North America; 28 (3): 317-29.
17. EKG.Academy. (2017). Introduction to pacemaker rhythms. Clinical Skills Education. Retrieved online at www.ekg.academy/pacemaker-rhythms.
18. Prutkin, J. (2017). EKG Tutorial: Pacemakers. UpToDate. Retrieved from https://www.uptodate.com/contents/ecg-tutorial-pacemakers?source=search_result&search=pacemaker+rhythm&selectedTitle=2~150
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19. Mount, D. (2017). Clinical manifestations and treatment of hypokalemia in adults. UpToDate. Retrieved online at https://www.uptodate.com/contents/clinical-manifestations-and-treatment-of-hypokalemia-in-adults?source=search_result&search=hypokalemia&selectedTitle=1~150.
20. He, J., Tse, et. al. (2017). P-Wave indices and risk of ischemic stroke. American Heart Association. Retrieved online at http://stroke.ahajournals.org/content/early/2017/07/05/STROKEAHA.117.017293?download=true
21. Zimetbaum, P. et al. (2017). Clinical features of congenital long QT syndrome. UpToDate. Retrieved online at https://www.uptodate.com/contents/clinical-features-of-congenital-long-qt-syndrome?source=search_result&search=torsades%20de%20pointes&selectedTitle=3~150.
22. Yap, Y.G. and Camm, A.J. (2017). "Drug induced QT prolongation and torsades de pointes". Heart. 89 (11): 1363–1372. ISSN 1355-6037. PMC 1767957
23. Park, D.S. and Fishman, G. (2017). Development and Function of the Cardiac Conduction System in Health and Disease. J Cardiovasc Dev Dis; 4(2). pii: 7. doi: 10.3390/jcdd4020007.
24. Mayo Clinic. (n.d.). Supraventricular tachycardia. Mayo. Retrieved online at http://www.mayoclinic.org/diseases-conditions/supraventricular-tachycardia/symptoms-causes/syc-20355243
25. Mayo Clinic. (n.d.). Ventricular tachycardia. Mayo. Retrieved online at http://www.mayoclinic.org/diseases-conditions/ventricular-tachycardia/symptoms-causes/syc-20355138
26. Shah, S.N. (2015). Asystole. Retrieved from http://emedicine.medscape.com/article/757257-overview
27. van der Lende, M., et al. (2016). Cardiac arrhythmias during or after epileptic seizures. J Neurol Neurosurg Psychiatry. 87 (1):69-74
28. Shah, S.N. (2016). Pulseless electrical activity. Retrieved online at http://emedicine.medscape.com/article/161080-overview
29. Mayo Clinic. (n.d.). Pacemakers. Mayo. Retrieved online at http://www.mayoclinic.org/tests-procedures/pacemaker/home/ovc-20198445
30. The Journal of Family Medicine. (n.d.). EKG PR interval abnormalities. Retrieved online at http://www.mdedge.com/jfponline/dsm/4899/hospital-medicine/ekg-pr-interval-abnormalities
31. MedicineNet.com. (2016). Syncope. Retrieved online at https://www.medicinenet.com/script/main/art.asp?articlekey=5612
nursece4less.com nursece4less.com nursece4less.com nursece4less.com
46
32. Iyasere, C.A. (n.d.). EKG: PR interval abnormalities. Journal of family practice. Retrieved online at http://www.mdedge.com/jfponline/dsm/4899/hospital-medicine/ekg-pr-interval-abnormalities
33. Goldberger’s Clinical Electrocardiography: A Simplified Approach, 7th ed. ISBN-13: 978-0323087865
34. Ferri, F. (2014). Ferri's Clinical Advisor. 1st Ed. eBook ISBN: 9780323084307
35. Homoud, M.K. (2017). Sinus bradycardia. UpToDate. Retrieved online at https://www.uptodate.com/contents/sinus-bradycardia?source=search_result&search=bradycardia&selectedTitle=1%7E150
36. ACLS Training Center. (2017). ACLS bradycardia algorithm. Retrieved online at https://www.acls.net/acls-bradycardia-algorithm.htm
37. Sauer, W. (2017). Second degree atrioventricular block: Mobitz type I (Wenckebach type). UpToDate. Retrieved online at https://www.uptodate.com/contents/second-degree-atrioventricular-block-mobitz-type-i-wenckebach-block?source=search_result&search=mobitz&selectedTitle=1~40
38. Sauer, W. (2017). Second degree atrioventricular block: Mobitz type II. UpToDate. Retrieved online at https://www.uptodate.com/contents/second-degree-atrioventricular-block-mobitz-type-ii?source=search_result&search=mobitz&selectedTitle=2~40
39. Colucci, W.S. (2017). Drugs that should be avoided or used with caution in patients with heart failure. UpToDate. Retrieved online at https://www.uptodate.com/contents/drugs-that-should-be-avoided-or-used-with-caution-in-patients-with-heart-failure?source=search_result&search=torsade&selectedTitle=50~145
40. Dave, J. (2017). Torsade de Pointes. Medscape. Retrieved online at http://emedicine.medscape.com/article/1950863-overview
41. Jackobson, G., et al. (2016). Reckless administration of QT interval-prolonging agents in elderly patients with drug-induced torsade de pointes. Z Gerontol Geriatr.
42. Cho Y. (2016). Management of patients with long QT syndrome. Korean Circ J. 46 (6):747-52.
43. Baker, W.L. (2016). Treating arrhythmias with adjunctive magnesium: identifying future research directions. Eur Heart J Cardiovasc Pharmacother.
44. Kaye, A.D., et al. (2013). QT interval abnormalities: risk factors and perioperative management in long QT syndromes and Torsades de Pointes. J Anesth. 2013. 44
45. Overbey, A.N., et. al. (2013). Overdrive pacing in a patient with incessant torsades de pointes. BMJ Case Rep. doi: 10.1136/bcr-2013-
nursece4less.com nursece4less.com nursece4less.com nursece4less.com
47
200146. PMCID: PMC3822076. Retrieved online at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3822076/
46. Mayo Clinic. (n.d.). Long QT Syndrome. Mayo. Retrieved online at http://www.mayoclinic.org/diseases-conditions/long-qt-syndrome/symptoms-causes/syc-20352518
47. Knight, B.P. (2017). Patient education: Implantable cardioverter-fibrillators. UpToDate. Retrieved online at https://www.uptodate.com/contents/implantable-cardioverter-defibrillators-beyond-the-basics?source=search_result&search=cardiac+rhythms&selectedTitle=1~29
48. Ganz, L.I. (2017). General principles of the implantable cardioverter-defibrillator. UpToDate. Retrieved online at https://www.uptodate.com/contents/general-principles-of-the-implantable-cardioverter-defibrillator?source=search_result&search=ICD&selectedTitle=1%7E150
49. Knight, B.P. (2017). Patient education: Wolff-Parkinson-White syndrome. UpToDate. Retrieved online at https://www.uptodate.com/contents/wolff-parkinson-white-syndrome-beyond-the-basics?source=search_result&search=cardiac+resynchronization&selectedTitle=10~35
50. Knight, B.P. (2017). Patient education: Cardioversion. UpToDate. Retrieved online at https://www.uptodate.com/contents/cardioversion-beyond-the-basics?source=search_result&search=tachycardia&selectedTitle=4~27
51. Mayo Clinic. (n.d.). Cardioversion. Mayo. Retrieved online at http://www.mayoclinic.org/home/ovc-20336882
52. Chen, M.A. (2016). Cardioversion. National Institutes for Health. Retrieved online at www.nlm.nih.gov/medlineplus/ency/article/007110.htm
53. National Heart, Lung, and Blood Institute. (2016). Cardioversion. Retrieved online at https://www.nhlbi.nih.gov/health/health-topics/topics/crv/
54. American Heart Association. (2016). Non-surgical procedures for atrial fibrillation (AFib or AF). AHA. Retrieved online at http://www.heart.org/HEARTORG/Conditions/Arrhythmia/AboutArrhythmia/Non-surgical-Procedures-for-AF_UCM_423782_Article.jsp#.Wd7AsRNSyT8
55. Heart Rhythm Society. (n.d.). Cardioversion. Retrieved online at http://www.hrsonline.org/Patient-Resources/Treatment/Cardioversion#axzz2QAR9BBOa
nursece4less.com nursece4less.com nursece4less.com nursece4less.com
48
56. Prutkin, J.M. (2017). ECG tutorial: Pacemakers. UpToDate. Retrieved online at https://www.uptodate.com/contents/ecg-tutorial-pacemakers?source=search_result&search=pacemaker+rhythm&selectedTitle=2~150
57. Prutkin, J.M. (2016). ECG tutorial: Physiology of the conduction system. UpToDate. Retrieved online at http://www.uptodate.com/contents/ecg-tutorial-physiology-of-the-conduction-system
58. Prutkin, J.M. (2016). ECG tutorial: Electrical components of the ECG. UpToDate. Retrieved online at https://www.uptodate.com/contents/ecg-tutorial-electrical-components-of-the-ecg. source=search_result&search=ECG+leads&selected
59. Aruda-Olson, A.M. (2017). Overview of stress echocardiography. UpToDate. Retrieved online at https://www.uptodate.com/contents/overview-of-stress-echocardiography?source=search_result&search=echo+cardiogram&selectedTitle=1~150
60. Patel, A. (2015). Principles of Doppler echocardiography. UpToDate. Retrieved online at https://www.uptodate.com/contents/principles-of-doppler-echocardiography?source=search_result&search=doppler+echocardiogram&selectedTitle=1~150
61. Ahmed, H. (2017). Contrast echocardiography: Clinical applications. UpToDate. Retrieved online at https://www.uptodate.com/contents/contrast-echocardiography-clinical-applications?source=search_result&search=echo+cardiogram&selectedTitle=6~150
62. Mor-Avi, V. and Lang, R.M. (2015). Three dimensional echocardiography. UpToDate. Retrieved online at https://www.uptodate.com/contents/three-dimensional-echocardiography?source=search_result&search=echocardiography&selectedTitle=2~150
63. Callans, D.J. (2017). Bundle branch reentrant ventricular tachycardia. UpToDate. Retrieved online at http://www.uptodate.com/contents/bundle-branch-reentrant-ventricular-tachycardia?source=search_result&search=bundle+branch&selectedTitle=3~150
64. Bauer, W. (2016). Normal sinus rhythm and sinus arrhythmia. UpToDate. Retrieved online at http://www.uptodate.com/contents/normal-sinus-rhythm-and-sinus-
nursece4less.com nursece4less.com nursece4less.com nursece4less.com
49
arrhythmia?source=search_result&search=sinus+rhythm&selectedTitle=1~150
65. Zimetbaum, P.J. and Wylie, J.V. (2016). Nonsustained ventricular tachycardia clinical manifestations, evaluation, and management. UpToDate. Retrieved from http://www.uptodate.com/contents/nonsustained-ventricular-tachycardia-clinical-manifestations-evaluation-and-management?source=search_result&search=ventricular+tachycardia&selectedTitle=1~150
66. Giardina, E. (2016). Therapeutic use of ibutilde. UpToDate. Retrieved online at http://www.uptodate.com/contents/therapeutic-use-of-ibutilide?source=search_result&search=ibutilide&selectedTitle=1~28
67. Knight, P.B. (2017). Cardioversion for specific arrhythmias. UpToDate. Retrieved online at http://www.uptodate.com/contents/cardioversion-for-specific-arrhythmias?source=search_result&search=cardioversion&selectedTitle=1~150
68. Knight, P.B. (2017). Basic principles and technique of electrical cardioversion and defibrillation. UpToDate. Retrieved online at http://www.uptodate.com/contents/basic-principles-and-technique-of-electrical-cardioversion-and-defibrillation?source=search_result&search=cardioversion&selectedTitle=3~150
69. Biase, L.D., Walsh, E.P. (2016). Treatment of arrhythmias associated with the Wolff-Parkinson-White syndrome. UpToDate. Retrieved online at http://www.uptodate.com/contents/treatment-of-symptomatic-arrhythmias-associated-with-the-wolff-parkinson-white-syndrome?source=search_result&search=Wolff&selectedTitle=1~86
70. Biase, L.D. and Walsh, E.P. (2016). Epidemiology, clinical manifestations, and diagnosis of the Wolff-Parkinson-White syndrome. UpToDate. Retrieved online at http://www.uptodate.com/contents/epidemiology-clinical-manifestations-and-diagnosis-of-the-wolff-parkinson-white-syndrome?source=search_result&search=Wolff&selectedTitle=2~86
71. Ganz, L.I. (2017). Cardiac implantable electronic devices: Long term complications. UpToDate. Retrieved online at http://www.uptodate.com/contents/cardiac-implantable-electronic-devices-long-term-complications?source=search_result&search=implantable+cariac+defibrillator&selectedTitle=3~150
72. Ganz, L.I. and Hayes, D.L. (2016). Cardiac implantable electronic devices: Patient follow-up. UpToDate. Retrieved online at http://www.uptodate.com/contents/cardiac-implantable-electronic-devices-patient-follow-
nursece4less.com nursece4less.com nursece4less.com nursece4less.com
50
up?source=search_result&search=implantable+cariac+defibrillator&selectedTitle=4~150
73. Ganz, L.I. (2016). General principles of the implantable cardioverter-defibrillator. UpToDate. Retrieved online at http://www.uptodate.com/contents/general-principles-of-the-implantable-cardioverter-defibrillator?source=search_result&search=implantable+cariac+defibrillator&selectedTitle=2~150
74. Kirkfeldt, R.E., et. al. (2013). Complications after cardiac implantable electronic device implantations: an analysis of a complete, nationwide cohort in Denmark. European Heart Journal, Volume 35, Issue 18, 7 May 2014, Pages 1186–1194, https://doi.org/10.1093/eurheartj/eht511. Retrieved from https://academic.oup.com/eurheartj/article/35/18/1186/461882/Complications-after-cardiac-implantable-electronic
75. Weinstock, J., et al. (2016). Subcutaneous implantable cardioverter defibrillators. UpToDate. Retrieved online at https://www.uptodate.com/contents/subcutaneous-implantable-cardioverter-defibrillators?source=search_result&search=implantable+defibrillator&selectedTitle=8~150
76. Garlitski, A.C. (2017). Cardiac implantable electronic device lead removal. UpToDate. Retrieved online at http://www.uptodate.com/contents/cardiac-implantable-electronic-device-lead-removal?source=search_result&search=implantable+cariac+defibrillator&selectedTitle=8~150
77. Schulman, P.M. (2017). Perioperative management of patients with a pacemaker or implantable cardioverter-defibrillator. UpToDate. Retrieved online at http://www.uptodate.com/contents/perioperative-management-of-patients-with-a-pacemaker-or-implantable-cardioverter-defibrillator?source=search_result&search=implantable+cariac+defibrillator&selectedTitle=6~150
78. American Heart Association. (2016). Living with your implantable cardioverter defibrillator. AHA. Retrieved online at http://www.heart.org/HEARTORG/Conditions/Arrhythmia/PreventionTreatmentofArrhythmia/Living-With-Your-Implantable-Cardioverter-Defibrillator-ICD_UCM_448462_Article.jsp#.WeE6ihNSyT8
79. Mayo Clinic. (n.d.). Wolff-Parkindson-White Syndrome. Mayo. Retrieved online at https://www.mayoclinic.org/diseases-conditions/wolff-parkinson-white-syndrome/symptoms-causes/syc-20354626
nursece4less.com nursece4less.com nursece4less.com nursece4less.com
51
80. Biase, L.D., Walsh, E.P. (2016). Atrioventricular reentrant tachycardia (AVRT) associated with an accessory pathway. UpToDate. Retrieved online at https://www.uptodate.com/contents/atrioventricular-reentrant-tachycardia-avrt-associated-with-an-accessory-pathway?source=search_result&search=Atrioventricular+reentrant+tachycardia&selectedTitle=1~60
81. Knight, B.P. (2017). Atrioventricular nodal reentrant tachycardia. UpToDate. Retrieved online at https://www.uptodate.com/contents/atrioventricular-nodal-reentrant-tachycardia?source=search_result&search=Atrioventricular+reentrant+tachycardia&selectedTitle=2~60
82. Ganz, L.I. (2017). Overview of catheter ablation of cardiac arrhythmias. UpToDate. Retrieved online at https://www.uptodate.com/contents/overview-of-catheter-ablation-of-cardiac-arrhythmias?source=search_result&search=radiofrequency+ablation+cardiac&selectedTitle=1~150
83. Passman, R. (2016). Catheter ablation to prevent recurrent atrial fibrillation: Clinical applications. UpToDate. Retrieved online at https://www.uptodate.com/contents/catheter-ablation-to-prevent-recurrent-atrial-fibrillation-clinical-applications?source=search_result&search=radiofrequency+ablation+cardiac&selectedTitle=2~150
84. Seslar, S.P., et al. (2014). Clinical features of congenital long QT syndrome. UpToDate. Retrieved online at https://www.uptodate.com/contents/clinical-features-of-congenital-long-qt-syndrome?source=search_result&search=long+qt+syndrome&selectedTitle=6~150
85. Zimetbaum, P.J. (2017). Pathophysiology of the long QT syndrome. UpToDate. Retrieved online at https://www.uptodate.com/contents/pathophysiology-of-the-long-qt-syndrome?source=search_result&search=long+qt+syndrome&selectedTitle=5~150
86. Berul, C.I., et al. (2017) Acquired long QT syndrome. UpToDate. Retrieved online at https://www.uptodate.com/contents/acquired-long-qt-syndrome?source=search_result&search=long+qt+syndrome&selectedTitle=1~150
87. Schwartz, P.J., Ackerman, M.J. (2017). Congenital long QT syndrome. UpToDate. Retrieved online at https://www.uptodate.com/contents/congenital-long-qt-syndrome-diagnosis?source=search_result&search=long+qt+syndrome&selectedTitle=2~150
nursece4less.com nursece4less.com nursece4less.com nursece4less.com
52
88. Zimetbaum, P.J., et al. (2017). Prognosis and management of congenital Long QT Syndrome. UpToDate. Retrieved online at https://www.uptodate.com/contents/prognosis-and-management-of-congenital-long-qt-syndrome?source=search_result&search=long+qt+syndrome&selectedTitle=3~150
89. Zimetbaum, P.J. (2016). Genetics of congenital and acquired long QT syndrome. UpToDate. Retrieved online at https://www.uptodate.com/contents/genetics-of-congenital-and-acquired-long-qt-syndrome?source=search_result&search=long+qt+syndrome&selectedTitle=4~150
90. National Institutes of Health. (2011). What is Long QT Syndrome? NIH. Retrieved online at https://www.nhlbi.nih.gov/health/health-topics/topics/qt
91. Patel, A. (2017). Transthoracic echocardiography: Normal cardiac anatomy and tomographic views. UpToDate. Retrieved online at https://www.uptodate.com/contents/transthoracic-echocardiography-normal-cardiac-anatomy-and-tomographic-views?source=search_result&search=echocardiograms&selectedTitle=1~150
92. Patel, A. and Kannam, J.P. (2017). Transesophageal echocardiography: Indications, complications, and normal views. UpToDate. Retrieved online at https://www.uptodate.com/contents/transesophageal-echocardiography-indications-complications-and-normal-views?source=search_result&search=echocardiograms&selectedTitle=4~150
93. Gorcsan, J. (2015). Tissue Doppler echocardiography. UpToDate. Retrieved online at https://www.uptodate.com/contents/tissue-doppler-echocardiography?source=search_result&search=echocardiograms&selectedTitle=5~150
94. Goldberger, A.L. (2017). Basic Principles of Electrocardiographic Interpretation. UpToDate. Retrieved online at https://www.uptodate.com/contents/basic-principles-of-electrocardiographic-interpretation?source=see_link
95. The Standard 12 Lead EKG (2016). University of Utah. Retrieved online at https://ecg.utah.edu/lesson/1
nursece4less.com nursece4less.com nursece4less.com nursece4less.com
53
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