Cardiology Nursing 1 Humber Final Exam
study set with 100% verified solutions-personalized success 2025
regular rhythm
Set by SA node at 60 to
100 bpm P waves
sinus rhythm
normal
normal
qrs PR
0.12 - 0.2
normal qrs less than 0.10
wide qrs is greater than 0.12
100-160
bpm SA
Sinus Tachycardia
node
reduced time for
ventricle filling assess
for SOB or chest pain
more prone to arrhythmia
a prolonged QT interval
normal electrical activity, providing synchrony between the
NSR reflects the heart's
atria and the ventricles.
sinus node discharges impulses too fast (100 - 160
Sinus tachycardia occurs when
the beats/minute). All other parameters are normal
1/54
, Normal response of heart in certain circumstances (for example
exercise)
• Begins and ends gradually in contrast to other tachycardias
• Usually benign arrhythmia that goes away when underlying cause is
treated
Facts about sinus tachycardia
• Common causes: Anxiety, hypoxia, hypovolemia,
hypotension, heart failure, pain, drugs that increase
sympathetic tone (epinephrine, norepinephrine, dopamine,
dobutamine, isoproterenol, nitroprusside), and drugs that
decrease parasympathetic tone (atropine)
• Persistent sinus tachycardia may result in decreased cardiac output
due to a
decrease in stroke volume. Cardiac output = stroke volume
×heart rate. A decrease in either stroke volume or heart
rate may result in a decrease in cardiac output.
the sinus node discharges impulses too slow (40
- 60 beats/minute). All other
Sinus bradycardia occurs when
parameters are normal.
regular rhythm, rate 40-
60 bpm Normal p
Sinus bradycardia features
waves
PR interval normal 0.12
to 0.2 QRS normal less
than 0.1
Normal response of heart in certain circumstances (for example
relaxation, sleep)
• Most common arrhythmia associated with acute
inferior wall myocardial infarction
• Other causes: Reperfusion rhythm following myocardial
Facts about sinus bradycardia reperfusion procedures (thrombolytic administration,
angioplasty); vagal stimulation; sleep apnea;
hyperkalemia; increased intracranial pressure; disease of
SA node; and
administration of drugs, such as digitalis, calcium
channel blockers, and beta blockers
• Persistent bradycardia may result in decreased cardiac
output due to a decrease in heart rate. Cardiac output =
stroke volume ×heart rate. A decrease in either
2/54
, stroke volume or heart rate may result in a decrease in cardiac
output.
No treatment is necessary if patient is asymptomatic.
• Symptomatic bradycardia is initially treated with oxygen
Treatment of sinus bradycardia
and atropine IV push. If unsuccessful, external pacing or
transvenous pacing may be used.
• Chronicsinus bradycardia may require a permanent pacemaker.
the sinus node discharges impulses irregularly. The heart
Sinus arrhythmia occurs when
rate may be normal range or slow. All other parameters
are normal.
irregular
rhythm rate
Sinus arrhythmia ECG features normal or slow
P waves
normal
PR interval normal 0.12
to 0.20 QRS normal
less than 0.1
Normal phenomenon usually associated with phases of
respiration (heart rate increases with inspiration and
decreases with expiration)
• Most commonly observed in infants, children, and young
Facts about sinus arrhythmia adults, although it may occur in any age-group
• Frequently occurs along with sinus bradycardia, in which
case it is usually called sinus arrhythmia with a
bradycardic rate
• Treatment: Does not require intervention unless
accompanied by symptomatic bradycardia (follow
symptomatic bradycardia protocols)
3/54
, A broad term used to describe a sudden pause in the basic
rhythm with one or more missing beats; two rhythms fall
Sinus pause
under this category:
Sinus arrest and Sinus exit block
SA node fails to initiate impulse; represents a problem with
sinus arrest
SA node automaticity; basic rhythm does not resume on
time following pause.
SA node initiates impulse, but impulse is blocked as it exits
Sinus exit block SA node; represents a problem with SA node
conductivity; basic rhythm resumes on time following
pause.
Rhythm: basic is regular with
sudden pause with one or more
missing beats, HR may slow for
several beats after pause but then
return to basic rate.
P waves: sinus with basic rhythm,
absent during pause
Sinus arrest and sinus exit block
PR interval: normal during basic,
ECG
absent during pause
QRS normal during basic, absent during pause
Sinus block: basic rhythm resumes
on time after pause
Sinus arrest: basic rhythm does not
resume on time after pause
irregular sinus rhythm can be During Inspiration, the Sinus Node
associated with phases of fires faster During Expiration, the
respiration Sinus Node slows down
the spread of the electrical stimulus through the heart
Depolarization
muscle, producing the P wave from the atria and the QRS
complex from the ventricles
the recovery of the stimulated muscle to the resting state,
Repolarization
producing the ST segment, the T wave, and the U wave
white - right
arm black -
Five lead system lead left arm
placement
green -
4/54
study set with 100% verified solutions-personalized success 2025
regular rhythm
Set by SA node at 60 to
100 bpm P waves
sinus rhythm
normal
normal
qrs PR
0.12 - 0.2
normal qrs less than 0.10
wide qrs is greater than 0.12
100-160
bpm SA
Sinus Tachycardia
node
reduced time for
ventricle filling assess
for SOB or chest pain
more prone to arrhythmia
a prolonged QT interval
normal electrical activity, providing synchrony between the
NSR reflects the heart's
atria and the ventricles.
sinus node discharges impulses too fast (100 - 160
Sinus tachycardia occurs when
the beats/minute). All other parameters are normal
1/54
, Normal response of heart in certain circumstances (for example
exercise)
• Begins and ends gradually in contrast to other tachycardias
• Usually benign arrhythmia that goes away when underlying cause is
treated
Facts about sinus tachycardia
• Common causes: Anxiety, hypoxia, hypovolemia,
hypotension, heart failure, pain, drugs that increase
sympathetic tone (epinephrine, norepinephrine, dopamine,
dobutamine, isoproterenol, nitroprusside), and drugs that
decrease parasympathetic tone (atropine)
• Persistent sinus tachycardia may result in decreased cardiac output
due to a
decrease in stroke volume. Cardiac output = stroke volume
×heart rate. A decrease in either stroke volume or heart
rate may result in a decrease in cardiac output.
the sinus node discharges impulses too slow (40
- 60 beats/minute). All other
Sinus bradycardia occurs when
parameters are normal.
regular rhythm, rate 40-
60 bpm Normal p
Sinus bradycardia features
waves
PR interval normal 0.12
to 0.2 QRS normal less
than 0.1
Normal response of heart in certain circumstances (for example
relaxation, sleep)
• Most common arrhythmia associated with acute
inferior wall myocardial infarction
• Other causes: Reperfusion rhythm following myocardial
Facts about sinus bradycardia reperfusion procedures (thrombolytic administration,
angioplasty); vagal stimulation; sleep apnea;
hyperkalemia; increased intracranial pressure; disease of
SA node; and
administration of drugs, such as digitalis, calcium
channel blockers, and beta blockers
• Persistent bradycardia may result in decreased cardiac
output due to a decrease in heart rate. Cardiac output =
stroke volume ×heart rate. A decrease in either
2/54
, stroke volume or heart rate may result in a decrease in cardiac
output.
No treatment is necessary if patient is asymptomatic.
• Symptomatic bradycardia is initially treated with oxygen
Treatment of sinus bradycardia
and atropine IV push. If unsuccessful, external pacing or
transvenous pacing may be used.
• Chronicsinus bradycardia may require a permanent pacemaker.
the sinus node discharges impulses irregularly. The heart
Sinus arrhythmia occurs when
rate may be normal range or slow. All other parameters
are normal.
irregular
rhythm rate
Sinus arrhythmia ECG features normal or slow
P waves
normal
PR interval normal 0.12
to 0.20 QRS normal
less than 0.1
Normal phenomenon usually associated with phases of
respiration (heart rate increases with inspiration and
decreases with expiration)
• Most commonly observed in infants, children, and young
Facts about sinus arrhythmia adults, although it may occur in any age-group
• Frequently occurs along with sinus bradycardia, in which
case it is usually called sinus arrhythmia with a
bradycardic rate
• Treatment: Does not require intervention unless
accompanied by symptomatic bradycardia (follow
symptomatic bradycardia protocols)
3/54
, A broad term used to describe a sudden pause in the basic
rhythm with one or more missing beats; two rhythms fall
Sinus pause
under this category:
Sinus arrest and Sinus exit block
SA node fails to initiate impulse; represents a problem with
sinus arrest
SA node automaticity; basic rhythm does not resume on
time following pause.
SA node initiates impulse, but impulse is blocked as it exits
Sinus exit block SA node; represents a problem with SA node
conductivity; basic rhythm resumes on time following
pause.
Rhythm: basic is regular with
sudden pause with one or more
missing beats, HR may slow for
several beats after pause but then
return to basic rate.
P waves: sinus with basic rhythm,
absent during pause
Sinus arrest and sinus exit block
PR interval: normal during basic,
ECG
absent during pause
QRS normal during basic, absent during pause
Sinus block: basic rhythm resumes
on time after pause
Sinus arrest: basic rhythm does not
resume on time after pause
irregular sinus rhythm can be During Inspiration, the Sinus Node
associated with phases of fires faster During Expiration, the
respiration Sinus Node slows down
the spread of the electrical stimulus through the heart
Depolarization
muscle, producing the P wave from the atria and the QRS
complex from the ventricles
the recovery of the stimulated muscle to the resting state,
Repolarization
producing the ST segment, the T wave, and the U wave
white - right
arm black -
Five lead system lead left arm
placement
green -
4/54
