APEX: EKG monitors & equipment
Question and answers 100% correct
2026/2027
Which pathway depolarizes the left atrium?
A. Thorel tract
B. Bachman bundle
C. Kent bundle
D. Wenckebach tract - correct answer B. Bachman. Bundle
There are 3 internodal tracts that travel from the SA to AV node:
1. Anterior internodal tract (gives rise to Bachmann bundle)
2. Middle internodal tract (Wenckebach tract)
3. Posterior internodal tract (Thorel tract)
Conduction velocities if cardiac conduction pathway from slowest to fastest: - correct answer AV node
SA node
Myocardial muscle cells
HIS bundle
Bundle branches
Purkinje fibers
Match each phase of the ventricular action potential to its corresponding component on the EKG
waveform:
Phase 0
,Phase 2
Phase 3
T wave
QT interval
QRS complex - correct answer Phase 0- QRS
phase 2- QT interval
Phase 3- T wave
There are 5 phases of ventricular action potential:
0= rapid depolarization (QRS) - Na IN
1= initial repolarization(QRS) - Cl in/K+ OUT
2= plateau phase (QT interval)-Ca IN/K out
3= final repolarization (T wave)- K+ OUT
4= resting phase (T to QRS)- K+ leak
Key components of the EKG: - correct answer P wave- atrial depolarization begins
PR interval- atrial depolarization complete
QRS- atrial repolarization + ventricular depolarization
ST segment- ventricular depolarization complete
T wave- ventricular repolarization begins
Match each disease with the EKG abnormality that it is most likely to cause:
, Hypokalemia
WPW
Pericarditis
Intracranial hemorrhage
PR interval depression
U wave
Peaked T wave
Delta wave - correct answer Hypokalemia- U wave
WPW- Delta wave
Pericarditis- PR interval depression
Intracranial hemorrhage- Peaked T wave
Q waves suggest myocardial infarction if: - correct answer Amplitude is greater than 1/3 of R wave
Duration is greater than 0.04 secs
Depth is greater than 1mm
Peaked T wave causes - correct answer Myocardial ischemia, Hyperkalemia, left ventricular
hypertrophy, intracranial bleeding
Hypokalemia changes in ECG - correct answer Increased PR interval
increased QT interval
T wave flattening
ST depression
U wave
Question and answers 100% correct
2026/2027
Which pathway depolarizes the left atrium?
A. Thorel tract
B. Bachman bundle
C. Kent bundle
D. Wenckebach tract - correct answer B. Bachman. Bundle
There are 3 internodal tracts that travel from the SA to AV node:
1. Anterior internodal tract (gives rise to Bachmann bundle)
2. Middle internodal tract (Wenckebach tract)
3. Posterior internodal tract (Thorel tract)
Conduction velocities if cardiac conduction pathway from slowest to fastest: - correct answer AV node
SA node
Myocardial muscle cells
HIS bundle
Bundle branches
Purkinje fibers
Match each phase of the ventricular action potential to its corresponding component on the EKG
waveform:
Phase 0
,Phase 2
Phase 3
T wave
QT interval
QRS complex - correct answer Phase 0- QRS
phase 2- QT interval
Phase 3- T wave
There are 5 phases of ventricular action potential:
0= rapid depolarization (QRS) - Na IN
1= initial repolarization(QRS) - Cl in/K+ OUT
2= plateau phase (QT interval)-Ca IN/K out
3= final repolarization (T wave)- K+ OUT
4= resting phase (T to QRS)- K+ leak
Key components of the EKG: - correct answer P wave- atrial depolarization begins
PR interval- atrial depolarization complete
QRS- atrial repolarization + ventricular depolarization
ST segment- ventricular depolarization complete
T wave- ventricular repolarization begins
Match each disease with the EKG abnormality that it is most likely to cause:
, Hypokalemia
WPW
Pericarditis
Intracranial hemorrhage
PR interval depression
U wave
Peaked T wave
Delta wave - correct answer Hypokalemia- U wave
WPW- Delta wave
Pericarditis- PR interval depression
Intracranial hemorrhage- Peaked T wave
Q waves suggest myocardial infarction if: - correct answer Amplitude is greater than 1/3 of R wave
Duration is greater than 0.04 secs
Depth is greater than 1mm
Peaked T wave causes - correct answer Myocardial ischemia, Hyperkalemia, left ventricular
hypertrophy, intracranial bleeding
Hypokalemia changes in ECG - correct answer Increased PR interval
increased QT interval
T wave flattening
ST depression
U wave
