CPO ECG QUIZ EXAM 2025/2026 QUESTIONS WITH
SOLUTIONS GRADED A+
✔✔SNS Receptors - ✔✔sympathetic response, increases contractility
- increases HR, conduction rate, contractility, and irritability
✔✔PNS receptors - ✔✔parasympathetic response, decreases contractility
- decreases HR, conduction rate, contractility, and irritability
✔✔conduction system flow - ✔✔SA node > AV node > AV junction > bundle of His >
bundle branches (R and L)> Purkinje fibers
✔✔SA node - ✔✔main pacemaker
R atrial epicardium
rate 60-100bpm
✔✔AV node - ✔✔slows impulse to allow for atrial kick (atria systole)
✔✔AV junction - ✔✔backup pacemaker
rate 40-60 bpm
✔✔bundle of His - ✔✔carries impulses to branches
✔✔R bundle branch - ✔✔carries impulses to the right ventricle.
✔✔L bundle branch - ✔✔carries impulses to the left ventricle.
✔✔purkinje fibers - ✔✔fibers in the ventricles causing them to contract
- can be backup pacemaker
- rate 20-40bpm
✔✔Y axis on ECG - ✔✔voltage (mV)
✔✔X axis on ECG - ✔✔time (sec)
✔✔Einthoven's Triangle - ✔✔the leads between the three limb electrodes, has a charge
to record electrical potentials as heart beats
✔✔How to diagnose ST elevation - ✔✔must be present in 2 leads , do 12lead
✔✔electromechanical activity (3 phases) - ✔✔1. depolarization
2. repolarization
3. return to resting membrane potential
, ✔✔relative refractory period - ✔✔begins middle of t wave, ends at the end of t wave
"vulnerable period"
phase of refractory period when depolarization CAN OCCUR AGAIN
stimulus during this period is life threatening, R on T phenomenon
✔✔treatment long QT - ✔✔- IV magnesium (torsades)
- Defib
- Pacing
✔✔Lead 1 - ✔✔Left arm (-) to right arm (+)
✔✔Lead 2 - ✔✔right arm (-) to left leg (+)
✔✔Lead 3 - ✔✔left arm (-) to left leg (+)
✔✔ECG components (P wave) - ✔✔atrial depolarization
✔✔ECG components (PR interval) - ✔✔beginning of atrial depolarization to beginning
ventricular depolarization
✔✔ECG components (PR segment) - ✔✔represents impulse delay in AV node
✔✔ECG components (QRS) - ✔✔ventricular depolarization
✔✔ECG components (T wave) - ✔✔ventricular repolarization
✔✔ECG components (QT interval) - ✔✔ventricular depolarization and repolarization, be
concerned if QT >0.44 and bradycardic
✔✔Normal Sinus Rhythm
Rate = ?
P:QRS = ?
PR Interval = ?
QRS Interval = ?
QT interval = ? - ✔✔Rate = 60-100
P:QRS = 1:1, regular
PR = 0.12 - 0.2
QRS = 0..06 - 0.12
QT = < 0.44
✔✔Sinus Bradycardia treatment - ✔✔Atropine 1mg
Vagal stimulation
Pace
SOLUTIONS GRADED A+
✔✔SNS Receptors - ✔✔sympathetic response, increases contractility
- increases HR, conduction rate, contractility, and irritability
✔✔PNS receptors - ✔✔parasympathetic response, decreases contractility
- decreases HR, conduction rate, contractility, and irritability
✔✔conduction system flow - ✔✔SA node > AV node > AV junction > bundle of His >
bundle branches (R and L)> Purkinje fibers
✔✔SA node - ✔✔main pacemaker
R atrial epicardium
rate 60-100bpm
✔✔AV node - ✔✔slows impulse to allow for atrial kick (atria systole)
✔✔AV junction - ✔✔backup pacemaker
rate 40-60 bpm
✔✔bundle of His - ✔✔carries impulses to branches
✔✔R bundle branch - ✔✔carries impulses to the right ventricle.
✔✔L bundle branch - ✔✔carries impulses to the left ventricle.
✔✔purkinje fibers - ✔✔fibers in the ventricles causing them to contract
- can be backup pacemaker
- rate 20-40bpm
✔✔Y axis on ECG - ✔✔voltage (mV)
✔✔X axis on ECG - ✔✔time (sec)
✔✔Einthoven's Triangle - ✔✔the leads between the three limb electrodes, has a charge
to record electrical potentials as heart beats
✔✔How to diagnose ST elevation - ✔✔must be present in 2 leads , do 12lead
✔✔electromechanical activity (3 phases) - ✔✔1. depolarization
2. repolarization
3. return to resting membrane potential
, ✔✔relative refractory period - ✔✔begins middle of t wave, ends at the end of t wave
"vulnerable period"
phase of refractory period when depolarization CAN OCCUR AGAIN
stimulus during this period is life threatening, R on T phenomenon
✔✔treatment long QT - ✔✔- IV magnesium (torsades)
- Defib
- Pacing
✔✔Lead 1 - ✔✔Left arm (-) to right arm (+)
✔✔Lead 2 - ✔✔right arm (-) to left leg (+)
✔✔Lead 3 - ✔✔left arm (-) to left leg (+)
✔✔ECG components (P wave) - ✔✔atrial depolarization
✔✔ECG components (PR interval) - ✔✔beginning of atrial depolarization to beginning
ventricular depolarization
✔✔ECG components (PR segment) - ✔✔represents impulse delay in AV node
✔✔ECG components (QRS) - ✔✔ventricular depolarization
✔✔ECG components (T wave) - ✔✔ventricular repolarization
✔✔ECG components (QT interval) - ✔✔ventricular depolarization and repolarization, be
concerned if QT >0.44 and bradycardic
✔✔Normal Sinus Rhythm
Rate = ?
P:QRS = ?
PR Interval = ?
QRS Interval = ?
QT interval = ? - ✔✔Rate = 60-100
P:QRS = 1:1, regular
PR = 0.12 - 0.2
QRS = 0..06 - 0.12
QT = < 0.44
✔✔Sinus Bradycardia treatment - ✔✔Atropine 1mg
Vagal stimulation
Pace
