DPTD 872: Electrocardiography
Name the parts of the cardiac conduction system
Sinoatrial Node (SA) Atrioventricular Node (AV) Bundle of His Purkinje Fibres
normal sinus rhythm (EKG)
same distance between P waves from one cardiac cycle to next, meaning SA node
is controlling HR
sinus bradycardia (EKG)
Will show a slow heart rate (below 60). This will compass more than 5 'big boxes'
between QRS's.
What are the causes of sinus bradycardia?
Exercise-training adaptation (enhanced SV)
medications (beta blockers)
decreased automaticity of SA node
TBI
increased vagal stimulation (increased PNS activity slows down heart)
True or False: sinus bradycardia is common in athletes and is an adaptation of high
exercise training
True
What are the signs and symptoms of sinus bradycardia?
*CAN BE asymptomatic.
fatigue, dizziness, presyncope, syncope, exercise intolerance, dyspnea, chest pain,
peripheral edema, cyanosis, confusion, lightheadedness
How would you treat sinus bradycardia?
atropine to increase HR or temporary pacemaker
*No treatment necessary unless patient is symptomatic
sinus tachycardia (EKG)
HR: >100 bpm
Shortened R-R intervals
QRS complexes have little space between
~2 boxes apart.
, True or False: sinus tachycardia is usually benign and sees an increased
sympathetic stimulation as a result of: fear, exercise, emotion or stimulants (caffeine,
nicotine, amphetamines, atropine)
True
What are the causes of sinus tachycardia?
fever, emotional and physical stress, heart failure, fluid volume loss, hyperthyroidism,
hypercalcemia, caffeine, nicotine, exercise, infection, anemia, myocardial injury and
medications.
What are the signs and symptoms of sinus tachycardia?
*usually asymptomatic
fatigue, dizziness, lightheadedness, pre syncope, syncope, exercise intolerance,
dyspnea, chest pain, peripheral edema, cyanosis, confusion
True or False: sinus tachycardia can be a normal response to exercise during
therapy and is usually no cause for alarm unless symptoms are present
True
What would be the treatment of sinus tachycardia?
removal of the stimuli or use of beta blockers
sinus arrhythmia (EKG)
P, QRS and T waves are all person,t impulse fro SA node is irregular, HR speeds up
and slows down
What are the causes of sinus arrhythmia?
Related to respiratory cycle. HR increases w/inspiration and decreases
w/expiration.
non respiratory causes: infections, medication or fever
True or False: sinus arrhythmia is usually asymptomatic
True
Sinus Pause
pause caused by delay in impulse being initiated in the SA node. pause is < 2 R-R
intervals
Name the parts of the cardiac conduction system
Sinoatrial Node (SA) Atrioventricular Node (AV) Bundle of His Purkinje Fibres
normal sinus rhythm (EKG)
same distance between P waves from one cardiac cycle to next, meaning SA node
is controlling HR
sinus bradycardia (EKG)
Will show a slow heart rate (below 60). This will compass more than 5 'big boxes'
between QRS's.
What are the causes of sinus bradycardia?
Exercise-training adaptation (enhanced SV)
medications (beta blockers)
decreased automaticity of SA node
TBI
increased vagal stimulation (increased PNS activity slows down heart)
True or False: sinus bradycardia is common in athletes and is an adaptation of high
exercise training
True
What are the signs and symptoms of sinus bradycardia?
*CAN BE asymptomatic.
fatigue, dizziness, presyncope, syncope, exercise intolerance, dyspnea, chest pain,
peripheral edema, cyanosis, confusion, lightheadedness
How would you treat sinus bradycardia?
atropine to increase HR or temporary pacemaker
*No treatment necessary unless patient is symptomatic
sinus tachycardia (EKG)
HR: >100 bpm
Shortened R-R intervals
QRS complexes have little space between
~2 boxes apart.
, True or False: sinus tachycardia is usually benign and sees an increased
sympathetic stimulation as a result of: fear, exercise, emotion or stimulants (caffeine,
nicotine, amphetamines, atropine)
True
What are the causes of sinus tachycardia?
fever, emotional and physical stress, heart failure, fluid volume loss, hyperthyroidism,
hypercalcemia, caffeine, nicotine, exercise, infection, anemia, myocardial injury and
medications.
What are the signs and symptoms of sinus tachycardia?
*usually asymptomatic
fatigue, dizziness, lightheadedness, pre syncope, syncope, exercise intolerance,
dyspnea, chest pain, peripheral edema, cyanosis, confusion
True or False: sinus tachycardia can be a normal response to exercise during
therapy and is usually no cause for alarm unless symptoms are present
True
What would be the treatment of sinus tachycardia?
removal of the stimuli or use of beta blockers
sinus arrhythmia (EKG)
P, QRS and T waves are all person,t impulse fro SA node is irregular, HR speeds up
and slows down
What are the causes of sinus arrhythmia?
Related to respiratory cycle. HR increases w/inspiration and decreases
w/expiration.
non respiratory causes: infections, medication or fever
True or False: sinus arrhythmia is usually asymptomatic
True
Sinus Pause
pause caused by delay in impulse being initiated in the SA node. pause is < 2 R-R
intervals
