CPO ECG EVALUATION TEST SHEET 2025/2026 QUESTIONS
WITH SOLUTIONS GRADED A+
✔✔What does 'excitability' refer to? - ✔✔The ability of the heart to respond to outside
stimuli? It can initiate an impulse (automaticity), but it is also affected by external
neurotransmitters, hormones and meds that can increase the rte and strength of
contraction of the heart
✔✔What are your SNS receptors? - ✔✔They are adrenergic receptors: beta 1 receptors
✔✔What are the PNS receptors? - ✔✔They are cholinergic receptors: Muscarinic
receptors
✔✔What is the main pacemaker of the heart? What is the rate? - ✔✔SA node (60-100
bpm)
✔✔Where is the SA node located? - ✔✔Right atrial epicardium, near the opening of the
SVC
✔✔Where does the impulse go after the SA node initiates it? - ✔✔It runs along the
intra-atrial tracts/internodal tracts. This carries the impulse throughout the right atria. It
will also go thru bachmann's bundle so that it can reach the left atrium.
✔✔What is after the intra-atrial tracts in the conduction pathway? - ✔✔The AV node
✔✔What does the AV node do? - ✔✔It filters out excess impulse from the atria, so that
they don't reach the ventricles. It also delays the impulse for 0.08-0.12 sec, which allows
for the atrial kick.
✔✔Following the AV node, the conduction pathway goes to what part next? What does
this part do? - ✔✔It does to the AV junction. It lies between the AV node and Bundle of
His. It will carry the impulse quickly. It can also act as a backup pacemaker if the SA
node fails.
✔✔What is the rate of the AV junction, as a pacemaker? - ✔✔40-60 bpm
✔✔`What does the bundle of His do? - ✔✔Carries impulses rapidly from AV junction to
the right and left bundle branches
✔✔What are the different bundle branches that exist? - ✔✔Right Bundle Branch (just
one)
Then Left main bundle branch that splits into the left anterior and left posterior (due to
the larger surface area)
, ✔✔What is the last pacemaker of the heart? What is the rate? - ✔✔The Purkinje fibers
They are small fibers that branch off the right and left bundle branches and extend into
the myocardium. They are the last back up pacemaker and have a rate of 20-40 bpm
✔✔Where are the ECG leads placed? - ✔✔White on right
Smoke over fire
Green is Right Leg
Brown is R chest, 4th intercostal space
✔✔What leads have positive deflections? - ✔✔Lead 1, 2 and 3
Lead 2 will usually be your most upright view
✔✔What lead will give you negative deflections? - ✔✔Lead v1
✔✔If your U wave is too prominent, what should you expect? - ✔✔It is usually <1/3 of T
wave
If too prominent, suspect hypokalemia, hypercalcemia, or hyperthyroidism
✔✔What does ST elevation indicate? - ✔✔myocardial injury / infarction
✔✔What does ST depression indicate? - ✔✔myocardial ischemia
✔✔How do you define myocardial injury using an ECG? - ✔✔You need to have ST
changes in at least two leads - so you need a 12 lead ECG
✔✔What does ST elevation after 6 weeks post MI indicate? - ✔✔Ventricular aneurysm
✔✔When you should be concerned with the length of your QT interval? - ✔✔> 0.44 sec
and patient is bradycardic
✔✔What is Bazett's formula? - ✔✔QTc = QT / Square root of RR
✔✔What are the risk factors for long QT? - ✔✔Bradycardia
Female > male
Time frame between menarche and menopause
Congenital alterations to cardiac ion channels
Hypocalcemia
Hypokalemia
Hypoagnesemia
Stimulants
Hypothermia
Insecticide Exposure
Multiple meds
WITH SOLUTIONS GRADED A+
✔✔What does 'excitability' refer to? - ✔✔The ability of the heart to respond to outside
stimuli? It can initiate an impulse (automaticity), but it is also affected by external
neurotransmitters, hormones and meds that can increase the rte and strength of
contraction of the heart
✔✔What are your SNS receptors? - ✔✔They are adrenergic receptors: beta 1 receptors
✔✔What are the PNS receptors? - ✔✔They are cholinergic receptors: Muscarinic
receptors
✔✔What is the main pacemaker of the heart? What is the rate? - ✔✔SA node (60-100
bpm)
✔✔Where is the SA node located? - ✔✔Right atrial epicardium, near the opening of the
SVC
✔✔Where does the impulse go after the SA node initiates it? - ✔✔It runs along the
intra-atrial tracts/internodal tracts. This carries the impulse throughout the right atria. It
will also go thru bachmann's bundle so that it can reach the left atrium.
✔✔What is after the intra-atrial tracts in the conduction pathway? - ✔✔The AV node
✔✔What does the AV node do? - ✔✔It filters out excess impulse from the atria, so that
they don't reach the ventricles. It also delays the impulse for 0.08-0.12 sec, which allows
for the atrial kick.
✔✔Following the AV node, the conduction pathway goes to what part next? What does
this part do? - ✔✔It does to the AV junction. It lies between the AV node and Bundle of
His. It will carry the impulse quickly. It can also act as a backup pacemaker if the SA
node fails.
✔✔What is the rate of the AV junction, as a pacemaker? - ✔✔40-60 bpm
✔✔`What does the bundle of His do? - ✔✔Carries impulses rapidly from AV junction to
the right and left bundle branches
✔✔What are the different bundle branches that exist? - ✔✔Right Bundle Branch (just
one)
Then Left main bundle branch that splits into the left anterior and left posterior (due to
the larger surface area)
, ✔✔What is the last pacemaker of the heart? What is the rate? - ✔✔The Purkinje fibers
They are small fibers that branch off the right and left bundle branches and extend into
the myocardium. They are the last back up pacemaker and have a rate of 20-40 bpm
✔✔Where are the ECG leads placed? - ✔✔White on right
Smoke over fire
Green is Right Leg
Brown is R chest, 4th intercostal space
✔✔What leads have positive deflections? - ✔✔Lead 1, 2 and 3
Lead 2 will usually be your most upright view
✔✔What lead will give you negative deflections? - ✔✔Lead v1
✔✔If your U wave is too prominent, what should you expect? - ✔✔It is usually <1/3 of T
wave
If too prominent, suspect hypokalemia, hypercalcemia, or hyperthyroidism
✔✔What does ST elevation indicate? - ✔✔myocardial injury / infarction
✔✔What does ST depression indicate? - ✔✔myocardial ischemia
✔✔How do you define myocardial injury using an ECG? - ✔✔You need to have ST
changes in at least two leads - so you need a 12 lead ECG
✔✔What does ST elevation after 6 weeks post MI indicate? - ✔✔Ventricular aneurysm
✔✔When you should be concerned with the length of your QT interval? - ✔✔> 0.44 sec
and patient is bradycardic
✔✔What is Bazett's formula? - ✔✔QTc = QT / Square root of RR
✔✔What are the risk factors for long QT? - ✔✔Bradycardia
Female > male
Time frame between menarche and menopause
Congenital alterations to cardiac ion channels
Hypocalcemia
Hypokalemia
Hypoagnesemia
Stimulants
Hypothermia
Insecticide Exposure
Multiple meds
