EKG Interpretation Newest Version (2026)
Actual Questions and Answers 100% Correct
(A+)
‣ P Wave -✓✓Atrial contraction
-isoelectric baseline right at starting point to go up
-the electrical potential has left the SA node , swept across the atria, and has
initiated atrial contraction
-don't want notching or peaking
‣ Sinoatrial Node (SA) -✓✓60-100
Dominant pacemaker of the heart, located in the ipper portion of the R atrium.
‣ Inernodal Pathways -✓✓direct electrical impulses between SA and AV nodes
‣ Bachman's Bundle -✓✓Direct electrical impulses between SA Node to the left
atrium
‣ Intrinsic Rates of Conduction -✓✓SA node: 60-100
AV node: 40-60
Bundle of His & Perk. Fib: 20-40
‣ AV node -✓✓40-60
part of the AV junctional tissue. slows conduction, creating slight delay before
impulses reach ventricles.
‣ Bundle of His -✓✓Transmits impulses to bundle branches. Located below AV
node
‣ Left Bundle branch -✓✓conducts impulses that lead to left ventricle
‣ Right Bundle branch -✓✓conducts impulses that lead to right ventricle
‣ Perkinje system -✓✓20-40
network of fibers that spread impulses rapidly throughout ventricular walls.
Located at terminal bundle branches.
,‣ Depolarization -✓✓the electrical charge of a cell is altered by a shift of
electrolytes on either side of the cell membrane. This change stimulates muscle
fiber to contract
‣ Repolarization -✓✓chemical pumps re-establish an internal negative charge as
the cells return to their resting state
‣ Automaticity -✓✓ability to initiate an impulse spontaneously and continuously;
all cells in the heart have this ability
-anything wrong with SA node, AV will kick in
‣ Excitability -✓✓ability to be electrically stimulated
-PVC's can cause this, throwing in extra beats on the EKG
-cells outside of normal conduction are firing at will
-caused by nicotine, caffeine, alcohol
‣ Conductivity -✓✓ability to transmit an impulse along a membrane in an orderly
manner
‣ contractility -✓✓ability to respond mechanically to an impulse
‣ Inotropic -✓✓stregnth of contraction
-preload: amount of filling in ventricles
afterload: amount of force heart has to overcome to eject a volume of blood
‣ chronotropic -✓✓rate of contraction
‣ dromotropic -✓✓speed of conduction
‣ ECG (EKG) -✓✓a series of waves and deflections recording the heart's electrical
activity from a certain view or lead
-lead 2: most common, best to watch
‣ Precordial Leads -✓✓over the heart
‣ Limb Leads -✓✓2 extra views out of this
-european way: put monitors over bony prominences
, ‣ Electrode placement -✓✓symmetrical placement on limbs or you could get
innaccurate readings
-white: right
-white clouds above green grass
-smoke over fire
‣ aVr -✓✓"no man's land"
-we use this lead as a confirmatory for something we are suspecting
-can't trust this lead
‣ Modified chest leads -✓✓are useful in detecting bundle branch blocks and
premature beats
‣ QT Interval -✓✓baseline of P wave before it takes off and just before it shoots
down to U wave
-time it takes to get from SA node to AV node
‣ 1 Little box -✓✓0.04 seconds
‣ 1 Big box -✓✓0.2 seconds
‣ Normal Sinus Rhythm -✓✓60-100
‣ PR Interval -✓✓.12-.20 seconds
-should be 3-5 little boxes
‣ QRS duration -✓✓0.04-0.12
-<3 little boxes
‣ 300 squares on ECG tracing -✓✓1 minute
‣ Six Second Strip -✓✓R-wave to R-wave in test strip gives you pulse in a 6
second window
‣ Digoxin -✓✓check apical pulse before giving (can slow down HR a lot)
Actual Questions and Answers 100% Correct
(A+)
‣ P Wave -✓✓Atrial contraction
-isoelectric baseline right at starting point to go up
-the electrical potential has left the SA node , swept across the atria, and has
initiated atrial contraction
-don't want notching or peaking
‣ Sinoatrial Node (SA) -✓✓60-100
Dominant pacemaker of the heart, located in the ipper portion of the R atrium.
‣ Inernodal Pathways -✓✓direct electrical impulses between SA and AV nodes
‣ Bachman's Bundle -✓✓Direct electrical impulses between SA Node to the left
atrium
‣ Intrinsic Rates of Conduction -✓✓SA node: 60-100
AV node: 40-60
Bundle of His & Perk. Fib: 20-40
‣ AV node -✓✓40-60
part of the AV junctional tissue. slows conduction, creating slight delay before
impulses reach ventricles.
‣ Bundle of His -✓✓Transmits impulses to bundle branches. Located below AV
node
‣ Left Bundle branch -✓✓conducts impulses that lead to left ventricle
‣ Right Bundle branch -✓✓conducts impulses that lead to right ventricle
‣ Perkinje system -✓✓20-40
network of fibers that spread impulses rapidly throughout ventricular walls.
Located at terminal bundle branches.
,‣ Depolarization -✓✓the electrical charge of a cell is altered by a shift of
electrolytes on either side of the cell membrane. This change stimulates muscle
fiber to contract
‣ Repolarization -✓✓chemical pumps re-establish an internal negative charge as
the cells return to their resting state
‣ Automaticity -✓✓ability to initiate an impulse spontaneously and continuously;
all cells in the heart have this ability
-anything wrong with SA node, AV will kick in
‣ Excitability -✓✓ability to be electrically stimulated
-PVC's can cause this, throwing in extra beats on the EKG
-cells outside of normal conduction are firing at will
-caused by nicotine, caffeine, alcohol
‣ Conductivity -✓✓ability to transmit an impulse along a membrane in an orderly
manner
‣ contractility -✓✓ability to respond mechanically to an impulse
‣ Inotropic -✓✓stregnth of contraction
-preload: amount of filling in ventricles
afterload: amount of force heart has to overcome to eject a volume of blood
‣ chronotropic -✓✓rate of contraction
‣ dromotropic -✓✓speed of conduction
‣ ECG (EKG) -✓✓a series of waves and deflections recording the heart's electrical
activity from a certain view or lead
-lead 2: most common, best to watch
‣ Precordial Leads -✓✓over the heart
‣ Limb Leads -✓✓2 extra views out of this
-european way: put monitors over bony prominences
, ‣ Electrode placement -✓✓symmetrical placement on limbs or you could get
innaccurate readings
-white: right
-white clouds above green grass
-smoke over fire
‣ aVr -✓✓"no man's land"
-we use this lead as a confirmatory for something we are suspecting
-can't trust this lead
‣ Modified chest leads -✓✓are useful in detecting bundle branch blocks and
premature beats
‣ QT Interval -✓✓baseline of P wave before it takes off and just before it shoots
down to U wave
-time it takes to get from SA node to AV node
‣ 1 Little box -✓✓0.04 seconds
‣ 1 Big box -✓✓0.2 seconds
‣ Normal Sinus Rhythm -✓✓60-100
‣ PR Interval -✓✓.12-.20 seconds
-should be 3-5 little boxes
‣ QRS duration -✓✓0.04-0.12
-<3 little boxes
‣ 300 squares on ECG tracing -✓✓1 minute
‣ Six Second Strip -✓✓R-wave to R-wave in test strip gives you pulse in a 6
second window
‣ Digoxin -✓✓check apical pulse before giving (can slow down HR a lot)
