1. Where is impulse generated?
    Sinoatrial (SA) node - right atrium near Sup. VC
  2. Where is the AV node?
    Posterior septal wall of right atrium near tricuspid valve
  3. What is the order of conduction?
    • SA node
    • AV node
    • AV (His) bundle
    • Right/Left bundle branches
    • Purkinje fiber network
  4. What are the Bipolar limb leads?
    • I - right arm to left arm
    • II - right arm to left leg
    • III - left arm to left leg
  5. What are the Augmented unipolar limb leads?
    • aVR - V to right arm
    • aVL - V to left arm
    • aVF - V to left leg
  6. What is the triangle made up by the bipolar limb leads?
    Einthoven's Triangle
  7. What is responsible for the P wave?
    Atrial muscle depolarization
  8. What is responsible for the QRS complex?
    • Ventricular depolarization
    • also, atrial repolarization
  9. PR interval
    Measure of conduction through the AV node
  10. ST segment
    Measure of time where all myocardium in Phase 2 plateau state
  11. What is responsible for the T wave?
    Repolarization of the ventricles
  12. What is responsible for the U wave?
    Repolarization of myocardial "M" cells
  13. What are the leads of a 12 lead ECG?
    • Bipolar (I, II, III)
    • Augmented unipolar (aVR, aVL, aVF)
    • Precordial leads (V1-V6)
  14. Define:
    1. Tachycardia
    2. Bradycardia
    3. Sinus rhythm
    • 1. >100 bpm
    • 2. <60 bpm
    • 3. impulse originates at SA node
  15. Define Mean QRS Vector
    How to determine?
    • Sum of all vectors in ventricles during depolarization
    • Closest to most positive lead
    • If both I and aVF have positive QRS, then probably normal
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