EKG KAISER STUDY GUIDE
,1. Cardiac Conduction Pathway System: SA node> AV node>
Bundle of His> Left and Right bundle branches> Purkinjie fibers
2. Pacemakers of the heart: eNatural: SA Node =
60-100 beats/minute eBackup: AV Node = 40-60
beats/minute
eBackup: Purkinje Fibers (ventricles) = 20-40 beats/minute
3. SA Node: • Intrinsic Pacemaker of the heart
• Rate 60-100 beats/min
• RA (Right Atrium), close to SVC (Superior Vena Cava)
• Blood supply from RCA (Right Coronary Artery) & LCA (Leftnary Artery)
Coro
4. Interatrial/Internodal Tracts: Transmits de to the AV
impulses from the SA no node through the RA &
LA
5. AV node: • Slows conduction (40-60 beats/min)
• Physiologic delay allows atrial kick on floor of RA near tricuspid
lve
va
6. Bundle of His: Bundle of cardiac muscle fibers lectrical
that conducts the e impulses from the AV node in the ventricles
the right atrium to the septum between and then to
the left and right ventricles.
scicles)
7. bundle branches: Right and Left (Left anterior & Left posterior
fa
entricle walls.
8. Purkinjie Fibers: Fibers from Bundle Branches imbedded into
the v
,9. Depolarization vs Repolarization: Depolarization -
electrical excitation of the cell membrane, normally followed by
mechanical contraction
Repolarization - return of cell membrane to its resting state,
normally followed by mechanical relaxation
10. Electrical and mechanical activity of the heart: eThe heart
has two activities that are performed rhythmically: electrical
activity followed by mechanical activity eElectrical activity always
precedes mechanical activity
, eIt is possible to have electrical activity without
mechanical response eAlways check the patient -
Do Not Depend on the Machine!!!
11. Measurement of the boxes in the ekg: eA standard ECG
is printed at 25mm per second or 25 small squares per second.
ed by 25 small
Since one second divid ed by the
boxes, then each 1 mm box = 0.04 seconds. The
larger boxes indicat heavier lines are equal to 0.20 olts (mV).
seconds.
eVoltage is measured along the vertical axis and is expressed in
milliv
The standard calibration is that a 1 mV signal produces a 10-
mm deflection (0.1 mV=1mm). Simply put 10 small squares
vertically is equal to 1 millivolt
12. EKG waveforms and intervals: eP wave - rounded with
upright deflection in lead II, atrial depolarization
ePR interval- delay @ AV junction
• measure from beginning of P wave to beginning of QRS
• Normal duration 0.12 - 0.20 seconds •
S wave - Negative deflection following the R-wave
eQRS complex - multiple components, Ventricular depolarization,
06 -0.11
- 0.
• Q wave - first negative deflection after P wave R wave
• Positive deflection after the Q
egins
eJ point - marks where the QRS complex ends and ing of the T
the ST segment b eST segment - normally
isoelectric line between QRS and the beginn wave
eQT interval - beginning of the QRS complex to the end of the T
wave; changes with heart rate, usually half of the R to R interval.
beginning of vent activation through Ventricular depolarization.
0.44 -0.48 (Rate dependent)
eT wave - follows the QRS; typically, larger than the P wave and
slightly asymmetric; Ventricular repolarization
,1. Cardiac Conduction Pathway System: SA node> AV node>
Bundle of His> Left and Right bundle branches> Purkinjie fibers
2. Pacemakers of the heart: eNatural: SA Node =
60-100 beats/minute eBackup: AV Node = 40-60
beats/minute
eBackup: Purkinje Fibers (ventricles) = 20-40 beats/minute
3. SA Node: • Intrinsic Pacemaker of the heart
• Rate 60-100 beats/min
• RA (Right Atrium), close to SVC (Superior Vena Cava)
• Blood supply from RCA (Right Coronary Artery) & LCA (Leftnary Artery)
Coro
4. Interatrial/Internodal Tracts: Transmits de to the AV
impulses from the SA no node through the RA &
LA
5. AV node: • Slows conduction (40-60 beats/min)
• Physiologic delay allows atrial kick on floor of RA near tricuspid
lve
va
6. Bundle of His: Bundle of cardiac muscle fibers lectrical
that conducts the e impulses from the AV node in the ventricles
the right atrium to the septum between and then to
the left and right ventricles.
scicles)
7. bundle branches: Right and Left (Left anterior & Left posterior
fa
entricle walls.
8. Purkinjie Fibers: Fibers from Bundle Branches imbedded into
the v
,9. Depolarization vs Repolarization: Depolarization -
electrical excitation of the cell membrane, normally followed by
mechanical contraction
Repolarization - return of cell membrane to its resting state,
normally followed by mechanical relaxation
10. Electrical and mechanical activity of the heart: eThe heart
has two activities that are performed rhythmically: electrical
activity followed by mechanical activity eElectrical activity always
precedes mechanical activity
, eIt is possible to have electrical activity without
mechanical response eAlways check the patient -
Do Not Depend on the Machine!!!
11. Measurement of the boxes in the ekg: eA standard ECG
is printed at 25mm per second or 25 small squares per second.
ed by 25 small
Since one second divid ed by the
boxes, then each 1 mm box = 0.04 seconds. The
larger boxes indicat heavier lines are equal to 0.20 olts (mV).
seconds.
eVoltage is measured along the vertical axis and is expressed in
milliv
The standard calibration is that a 1 mV signal produces a 10-
mm deflection (0.1 mV=1mm). Simply put 10 small squares
vertically is equal to 1 millivolt
12. EKG waveforms and intervals: eP wave - rounded with
upright deflection in lead II, atrial depolarization
ePR interval- delay @ AV junction
• measure from beginning of P wave to beginning of QRS
• Normal duration 0.12 - 0.20 seconds •
S wave - Negative deflection following the R-wave
eQRS complex - multiple components, Ventricular depolarization,
06 -0.11
- 0.
• Q wave - first negative deflection after P wave R wave
• Positive deflection after the Q
egins
eJ point - marks where the QRS complex ends and ing of the T
the ST segment b eST segment - normally
isoelectric line between QRS and the beginn wave
eQT interval - beginning of the QRS complex to the end of the T
wave; changes with heart rate, usually half of the R to R interval.
beginning of vent activation through Ventricular depolarization.
0.44 -0.48 (Rate dependent)
eT wave - follows the QRS; typically, larger than the P wave and
slightly asymmetric; Ventricular repolarization
