Using an organized approach to analyzing ECH tracings
helps to ensure that you identify all the characteristics seen in the tracing
The elements of the Nine-Step process include all of the following EXCEPT
axis
The normal heart rate in the adult is between __ and ___ beat per minute
60-100
During the ____ initiation of the impulse in the SA node, its movement through the atria and activation of the AV node occurs
P wave
The normal PR interval is ___ second in duration
0.12-0.20
The PR interval represents
depolarization of the heart from the SA node through the atria, AV node, and His-Perkinje system
The Q wave is the first ___ deflection after the PR segment
negative
Characteristics associated with normal sinus rhythm include
one upright P wave preceding each QRS complex
The term we use to describe the appearance of waveform is
morphology
Characteristics that differ from those seen with normal sinus can help us to identify various dysrhythmias and cardiac conditions
True
Using the 9 step process
allow you to identify the characteristics of the tracings you are analyzing
When we analyze an ECG tracing on the ECG monitor
it shows what is occurring in real time
The rhythm strip provides us
a good tool for identifying cardiac dysrhythmias
A 12 lead ECG tracing
yields much of the information needed to identify cardiac conditions
You are trying to determine if your patient, who is complaining of chest pain, is experiencing myocardial ischemia. The best way to do this is:
perform a 12 lead ECG
If the QRS complexes are close together the heart rate is
fast
Determining the heart rate helps you identify abnormal ECG rhythms
true
A benefit of using a shortcut method for determining heart rate is that it
is faster than counting the complexes found on a whole minutes worth of ECG tracing
The 6 second interval x 10 method
can be used to estimate the heart rate in irregular rhythms
The 300, 150, 100, 75, 60, 50 method
requires you to identify a start point from which to identify where the next R wave falls
To use the 1500 method,
count the number of small squares between two consecutive R waves and divide 1500 by that number
Which one of the following methods for determining the heart rate in a regular rhythm is the most accurate?
1500 method
The atrial heart rate is always the same as the ventricular heart rate
False
The average heart rate in the adult patient is between ___ beats per minute.
60-100
Tachycardia
may be brought about by exercise or exertion
It is unlikely that the patient's heart rate was actually 320 because
She was awake, her blood pressure was not low, she was able to answer questions (all of the above)
The most likely cause of the patient's fast heart rate was
anxiety
Normally the heart beats in a
regular, rhythmic fashion, producing a P wave, QRS complex, and T wave with each heartbeat
Determining the regularity of an ECG tracing
is considered an important analysis step
The distance between two consecutive R waves is called the
RR interval
An irregular rhythm
should be properly investigated
Calipers can be used to analyze an ECG by
placing one leg on a starting point and extending the second leg to the next consecutive waveform being assessed, then comparing this distance across the ECG strip
The paper and pen method
involves placing two marks on the paper, the first above one of the R waves on the ECG tracing and the second above the next consecutive R wave
To use the counting the small square method, you
count the number of small squares between the peaks of two consecutive R waves and then compare that to the other RR intervals
Which of the following methods for determining heart rhythm regularity is the easiest one, for which you can use readily available supplies
paper and pen method
A/an ____ irregular rhythm is one that appears mostly regular, but from time to time you see an area where it is irregular
occasionally
Early beats
cause the RR intervals between the normal and early beat to be shorter than normal
Failure of the SA node to initiate an impulse causes the
RR interval that occurs because of the dropped beat to be longer than normal
A/an ____ irregular rhythm is one where the P-P intervals and the R-R intervals vary only a bit
slightly
A patterned irregular rhythm is seen when
early beats occur every other complex, every third complex, or every fourth complex
With an irregular rhythm caused by a variable conduction ratio
the RR intervals will occasionally be different durations
The type of irregularity with this patient's ECG tracing means there is
no pattern to the irregularity (seen in irregular irregular rhythm)
To analyze the atrial activity of an ECG you should assess the
P waves
The amplitude of the P wave normally does not exceed
2.5 m
An upright, round P wave (in lead II) that precedes each QRS complex indicates that the electrical impulse originated in the
SA node and was carried through the atria in a normal manner
The characteristic considered normal (in lead II) is a/an
rounded and upright P wave
Which of the following is best evaluated by choosing the appropriate lead
P waves
With increased left atrial pressure and left atrial enlargement, the P wave is normally
notched or wide
Which of the following will produce P waves that look different than sinus P waves?
enlarged or damaged atria
An impulse that arises closer to the SA node
looks more like a normal P wave
Early beats that arise from the atria
may have P waves buried in the T wave of the preceding beat
With tachycardia that arises from the atria
the P wave looks different than P waves that arise from the SA node
An atrial pacemaker site that changes from location to location
P waves that continually change in appearance
When atria fire faster than 350 beats per minute, the P waves
are indiscernable; instead there is a chaotic looking baseline
Dysrhythmias that arise from AV junctional tissue have ___ P waves
inverted
With ventricular dysrhythmias, the P waves
are absent
Which of the following has more P waves than QRS complexes?
AV heart block
From where did the patient's dysrhythmia originate?
atria
The firing rate of the F wave is ___ bpm.
144
The appearance of the ___ is affected by the lead used.
QRS complexes
In lead II, the deflection of the QRS complex characteristically
positive
Analyzing the QRS complex helps identify how the electrical impulse is being carried through the
ventricles
The normal duration of the QRS complex is ___ seconds
0.06 to 0.10
An upright (in lead II), narrow QRS complex indicates that the electrical impulse originated
at or above the AV node and was carried through the ventricles in a normal manner
The R wave is the
first positive deflection in the QRS complex
Which of the following will produce normal QRS complexes
early beats that arise from the atria
Which of the following is true regarding the amplitude of QRS complexes
precordial leads have higher amplitudes than limb leads
Intraventricular conduction defect
causes the QRS complexes to appear abnormal
Low voltage or abnormally small QRS complexes are seen in
obese patients
Which of the following is the most common cause of intraventricular conduction defect?
bundle branch block
Bundle branch blocks
may be partial or complete
Aberrant conduction
occurs when the impulse reaches one of the bundle branches while it is still refractory
Early beats that arise from ventricles
produce QRS complexes that look different than those that arise above or at the AV junction
An escape pacemaker rhythm that arises from the ventricles has
wide and bizarre looking QRS complexes
Tachycardia that arises from the ventricles
wide and bizarre looking QRS complexes
With the most severe form of AV block, the QRS complexes
are slower than the P wave rate because there is complete blockage of the AV node
With ventricular fibrillation
a choatic wavy line is seen onthe ECG
Asystole
is seen as a flat line on the ECG
Where are the extra QRS complexes originating from
ventricles
The most likely cause of the patients extra beats is
ischemia
The duration of the PR interval ____ from beat to beat
is constant
PR interval is the distance from the
beginning of the P wave to the beginning of the Q wave
The PR interval denotes depolarization of the heart from the
SA node through atria, AV node, and His-Purkinje system
The normal duration of the PR interval is ___ seconds
0.12-0.20
A shorter than normal PR interval is less than ___ seconds
0.12
Which of the following characteristics is considered normal?
a PR interval that is 0.18 seconds in duration
Which of the following is characteristics of delayed conduction through the AV node?
constant PR intervals of greater than 0.20 seconds
With a pacemaker site than changes fro beat to beat throughout the atria, the PR intervals
vary
With AV heart block, the PR intervals may be all of the following EXCEPT
shorter in duration than 012 seconds
There will be an absence of PR intervals in
the most severe form of AV heart block
If there is an accessory pathway between the atria and ventricles, the PR intervals may
be less than 0.12 seconds in duration
PR segments are commonly described as
flat
The patient is most likely experiencing
AV heart block
The PR intervals that change in duration are considered
abnormal and characteristic of specific dysrhythmias
The ST segment represents
the beginning of ventricular repolarization
The ST segment is characteristically
neither positive nor negative
To measure the ST segment we draw a line from the ___ through the ____
PR segment, J point
An elevated ST segment is ____ the isoelectric line.
above
Convex shaped ST segment elevation is most often due to
myocardial injury
The T wave represents
ventricular repolarization
Which of the following is characteristics of normal T waves
larger than a P wave
The maximum amplitude of T waves in the precordial leads is __ mm in height.
10
To determine the amplitude of the T wave, you measure from the isoelectric line to the beginning of the waveform.
False
Inverted T waves may be seen with
myocardial ischemia
The QT interval represents the time needed for ventricular repolarization
false
The normal QT interval has a duration of ___ to ___ seconds
0.36-0.44
To measure the QT interval, we measure from the beginning of the ____ to the end of the ____
Q wave to T wave
Prolonged QT intervals may be seen with
congenital conduction system defect
Which of the following describes U waves
take the same direction as the T wave
Prominent U waves are most often seen with
hypokalemia
Your patient has a QT interval of 0.48 seconds in duration. THis is referred to as a ___ QT interval
prolonged
In the presence of myocardial ischemia or infarction, a prolonged QT internal can predispose the patient to
torsades de pointes
Elevated ST segments and inverted T waves on the ECG suggest the patient is experiencing
myocardial ischemia and injury
The patient's heart rate can be described as
bradycardic