anp lab 7 heart dynamics

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anp lab 7 heart dynamics
2012-12-03 21:05:27
anp lab heart dynamics

anp lab 7 heart dynamics
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  1. What does the intrinsic conduction system do
    sets the basic rhythm of the beating heart
  2. what does the intrinsic conduction system consist of
    autorythmic cardiac cells
  3. what do autorythmic cardiac cells do
    initiate and distribute impulses throughout the heart
  4. mass of autorythmic cells located in the right atrial wall near the entrance of the superior vena cava 
    SA node
  5. mass of autorhythmic cells located in the inferior portion of the internal septum abouve the tricuspid valve 
    AV node
  6. autorhythmic cells located in the inferior part of the interatrial septum the only electrical connection between atria and ventricles 
    AV bundle
  7. Two branches resulting from a splitting of the AV bundle conveys impulses down the interventricular septum
    Bundle Branches
  8. Fibers that run through the interventricular septum, penetrate the heart apex, turn superiorly and ramify in the ventricular walls 
    Purkinje fibers
  9. what does the P wave represent 
    atrial depolorization
  10. what does the QRS complex represent
    ventricular polorization
  11. the doe the T wave represent
    ventricular repolorization
  12. tracing on an ECG that results from the movement of the depolorization wave from SA node through Atria. it lasts about 0.08 Secs. atrial contraction follows
    P wave
  13. Tracing on an ECG that results from the ventricular depolorization. Atrial repolorization also occurs during this time. Lasts about 0.08 sec ventricular contraction follows
    QRS complex
  14. Tracing on an ECG caused by ventricular repolorization. It lasts about 0.10 secs ventricular relaxation follows
    T wave
  15. what does the cardiac cycle include 
    all the events related to the flow of blood through the heart during one complete beat
  16. what do heart valves do in response to differences in pressure on thier two sides
    open and close
  17. what are the 3 phases of the cardiac cycle
    • ventricular filing 
    • ventricular systole
    • isoventricular relaxation
  18. describe the flow of blood into the atria at the start of ventricullar filling
    are the valves open or closed at this point
    • blood flows passivly into the atria through open AV valves
    • open
  19. where does the blood go after it passes the AV valve

    at this point is the pressure higher or lower in the ventricles
    • ventricles
    • lower
  20. what happens when the atria contract
    force remaining blood into ventricles 
  21. what happens to interventricular pressure when the ventricles contract
    intraventricular pressure rises
  22. what happens to the AV valves when the ventricles contract 
    they close
  23. what does rising ventricular pressure open
    semi-lunar valves
  24. what happens when semi lunar valves are forced open 
    blood is ejected from the heart
  25. what happens during isovolumetric relaxation
    ventricles relax and ventricular pressure drops
  26. what does blood do during isovolumetric relaxation
  27. what happens to the semilunar valves during isovolumetric relaxation
    they close
  28. describe the ventricles after the semilunar valves close during isovolumetric relaxation 
    totally closed off
  29. what have the atria been doing while the ventricles have been contracting and relaxing during isovolumetric relaxation
    filling with blood
  30. what happens to the AV valves when atrial pressure exceeds ventricular pressure 
  31. describe the contraction of the atria 
    both contract at the same time
  32. describe the contraction of the ventricles
    both contract at the same time
  33. what do pressure changes reflect 
    alternating contraction and relaxationof the heart
  34. what does blood move along
    pressure gradient
  35. describe the pressure gradient blood moves along
    higher to lower gradient through any available opening
  36. what do pressure changes cause
    valves to open and close
  37. what does the opening and closing of the heart valves result in 
    keeps blood flowing in forward direction
  38. what is cardiac output 
    the amount of blood pumped out by each ventricle in one minute
  39. what 2 variable is cardiac output related to
    • heart rate 
    • stroke volume
  40. what si the equation for cardiac output 
    CO=HR X SV
  41. what is heart rate 
    number of times heart beats in one minute
  42. what is the average heart rate 
  43. what is stroke volume
    amount of blood pumped by each ventricle w each heart beat
  44. what is the average stroke volume 
    70 ml per beat
  45. what is stroke volume 
    represents the difference between end diastolic volume and systolic volume
  46. what is the equation for stroke volume
    SV = EDV - ESV
  47. what is the equation for stroke volume using average values
    70 ml/beat = 120 ml/beat - 50 ml/beat
  48. what is end diastolic volume (EDV) 
    amount of blood remaining in each ventricle at the end of diastolic relaxation
  49. what is end systolic volume (ESV)
    amount of blood remaining in each ventricle at the end of systole