Card Set Information

2013-02-19 22:46:04

Show Answers:

  1. what is the purpose of the cardiovascular system?
    they purpose is transport and deliver nutrients throughout the body
  2. in simple terms, what is the heart
    the heart is a pump which contracts to generate the pressures necessary to push blood throughout a closed system of blood vessels
  3. function of the artery
    carries blood away from the heart
  4. function of the vein
    carries blood to the heart
  5. name the two circuits that belong to the cardiovascular system
    systemic and pulmonary
  6. what does this mean: each "heart" pumps the same amount
    cardiac output for left heart (ventricle) normally equals cardiac output for tight heart (ventricle)
  7. what is the pericardial sac?
    the sac the surrounds the heart
  8. state the layers of the heart wall (deep to superficial)
    • - endocardium 
    • - myocardium
    • - visceral layer of serous pericardium 
    • - pericardial cavity (contains serous fluid)
    • - perietal layer of serous pericardium 
    • - fibrous pericardium
  9. Fibrous Pericardium
    is the outer most layer (superficial) of the heart wall. its made out of dense connective tissue which has a low compliance
  10. serous pericardium
    • is a double layer membrane 
    • - parietal 
    • - visceral
  11. parietal layer of serous pericardium
    line fibrous pericardium
  12. percardial fluid
    is serous fluid in the pericardial cavity. its purpose is to lubricate and decrease friction of the moving heart
  13. visceral layer of serous paricardium
    also known as epicardium and it covers the myocardium and is part of the heart wall
  14. percarditis
    is the inflammation of the paricardium
  15. what can cause pericarditis
    • - increase fluid
    • - increase thickness + viscosity 
    • - increase adhesion
    • - increase resistance due to friction (able to hear the friction rub)
    • - trauma
    • - chemo
    • - radiation
  16. pericarditis can cause what?
    - trauma
  17. pericardial tamponade
    - large build-up of fluid in pericardial sac affects cardiac function such as preventing it from expanding
  18. Pericardiocentesis
    process ofwithdrawing fluid with catheter
  19. the epicardium (visceral layer) is made up of what tissue?
    squamous epithelium, areolar CT and fat
  20. myocardium is made up of what tissue?
    • cardiac muscle which attatched to fibrous skeleton of the heart (composed of collagen and elastin)
    • - the arrangement of that muscle bundles allows wiring contraction
  21. the endocardium is made up of what tissue?
    areolar CT and epithelium
  22. what does this mean: muscle bundles allow wiring contraction
    serves a purpose of squeezing as much blood out of the heart as possible which each contraction
  23. which ventricle is thicker and why?
    • he left ventricular wall is thicker. why?think of their tasks- the right ventricle must generate enough pressure to send blood to the lungs and then back to then left heart
    • - the left ventricle must generate enough pressure to send blood throughout the systemic system
  24. right ventricle pumps blood to where?
    pumps blood to thoracic cavity (lungs)
  25. the ventricles have different what? and equal amounts of what?
    they have different pressures but the same amount of blood
  26. right atrium receives blood from which structures?
    • receives blood from (the blood is deoxygenated)
    • - superior vena cava
    • - inferior vena cava 
    • - coronary sinus (which drains coronary sinus)
  27. left atrium receives blood from where?
    receives blood from the pulmonary veins which returns blood draining lungs
  28. how many pulmonary veins are their
    there are 4 pulmonary veins which brings freshly oxygenated blood from the lungs
  29. right ventricle pumps blood where?
    pumps blood out to the pulmonary trunk (pulmoney arteries) to the lungs
  30. left ventricle pumps blood where?
    pumps blood out to the aorta to the systemic system (including coronary arteries)
  31. heart valves ensure what?
    ensure the prevention of backflow - blood going the wrong direction
  32. AV valves include which structures
    • - the tricuspid (right AV valve)
    • - bicuspid valve (left AV)
  33. bicuspid valve is also known as what?
    mitral valve
  34. semilunar valves include which structure?
    • - aortic SL 
    • - pulmonary SL
  35. pulmonary valves include what?
    • - tricuspid 
    • - pulmonary SL
  36. systemic valves include what ?
    • - bicuspid (mitral valve)
    • - Aortic SL
  37. chordae tendinae anchor which valves to the papillary muscles? why?
    the anchor the AV valves to prevent eversion
  38. isovolumetric
    ventricular volume is constant
  39. coronary circulation
    • - coronary arteries deliver blood to the cardiac muscle
    • - from the capillaries within the cardiac muscle the blood drains into the coronary vein
    • - coronary vein empties into the coronary sinus which then returns blood to the atrium
  40. what are the vessels in the coronary system?
    • - coronary arteries
    • - coornary veins
    • - coronary sinus
  41. blood flow disorders
    • - angina pectoris 
    • - myocardial infarction (heart attack)
  42. Angina Pectoris
    • vasal spasm (which are short lived) briefly cuts off blood flow, causes ischemia leading to pain
    • - there is no cell death, no death to cardiac muscle
  43. myocardial infarction (heart attack)
    Blockage of O2 to cardiac muscle; cell death
  44. cardiac muscle contain what structures?
    • - gap junctions
    • - intercalated disks
    • - bifurcations
    • - anastomoses
  45. Bifurcations
    the fork or branching part the cardiac muscle
  46. Anastomoses
    meaning the cardiac muscle interconnects freely
  47. intercalated disks
    Plasma membranes of adjacent cardiac cells connect by special junctions called intercalated disks,
  48. desmosomes
    for mechanical anchoring
  49. gap junctions
    allow ions, and thus electrical signals, to pass from cell to cell
  50. what do cardiac and skeletal muscles have in common
    • - both are striated 
    • - contraction mechanism
  51. Energy Requirements for Cardiac Muscle
    • • Lots of mitochondria
    • • NEED for O2!
    • • Fuel:– Glucose– Fatty acids– Lactate– Others
  52. resting potential for ventricular myocytes is what?
    -80 to -90 mV
  53. inward current refers to what?
    positive (going into the cell)
  54. outward current refers to what?
    positive out
  55. another term for discharged rate for pace maker?
    sinus rhythm
  56. p-wave
    correlates to atrial depolarization (followed by atrial contraction).
  57. p-r interval
    correlates to atrial depolarization (followed by atrial contraction).
  58. QRS- complex
    Depolarization of ventricles (followed by ventricular contraction).
  59. Q-T interval
    approximate length of time for ventricles to contract and begin to relax (ventricular depolarizationand repolarization)
  60. t-wave
    Repolarization of ventricles (relaxation).
  61. Disorders of Conduction System
    • - AV block ("heart block")
    • - ectopic focus
  62. AV heat block
    • not electrical connection between atria and ventricles 
    • - If complete “heart block”, complete absence of AV conduction – no electrical connection between atria andventricles. Each beats at its own pace (“ventricular escape”); resulting in ventricular beats which are too slow.Need a pacemaker to treat this.
  63. ectopic focus
    • – Abnormal pacemaker (in the wrong place)
    • – Here, many microfoci ofatrial myocardium areeach acting as ectopicfoci, activating a smalladjacent patch of muscle,leading to atrial fibrillation(canine.)
  64. heart extrinsic innervation factors
    • - ANS (parasympathetic and sympathetic)
    • - hormones

    which can cause increased contractility which increases contraction
  65. the medulla cardioacceletory controls what?
  66. the medulla cardioinhibitory
    controls the parasympathetic - primarily the vagus
  67. sympathetic controls what?
    • both the heart rate and innervates the ventricular muscle
    • – Increased cAMP à actson HCN channels toincrease rate ofpacemaker depolarization
    • – Prolonged opening of Ltype Ca++ channels(affects rate + strength)
  68. barorecptors control what?
    blood pressure
  69. parasympathetic (vagal) activity
    **Increased vagal activity slows SA nodal pacemakers via muscarinic receptors which:– Via an inhibitor G protein, inhibit adenyl cyclase thus decreases cAMP, leading to multiple effects.E.g., less cAMP acting on HCN channels a slows rate of pacemaker depolarization.– Activate Phospholipase C (via G protein) which opens K+ channels, increasing GK, which increasesoutward K+ currents a hyperpolarizes pacemaker cells a slows their depolarization.
  70. Excitation-Contraction Coupling
    • • SA node à depolarizationthroughout cardiacconduction system àmyocytes
    • • AP à T tubules, sensed byDHP receptor (part of L Ca++ channel complex);activates L type Ca++channels; influx of Ca++,which activates
    • • Ryanodine receptors(RyRs), intracellular ionchannels on SR membrane,release Ca++ from SR
    • • Ca++ binds troponin,activates cross bridgecycling; sliding of filaments
  71. what causes the lub sound
    closure of AV valve
  72. what makes the dub sound
    closure semilunar valves
  73. cardiac reserve = ?
    COmaximal - COresting
  74. stroke volume =?
    EDV - ESV
  75. EDV is determined by what?
    length of ventricular diastole and venous return
  76. ESV is determined by what?
    • - arterial blood pressure 
    • - contrcactiility
  77. Ejection fraction = ?
    (EDV - ESV) / EDV
  78. normal ejection fraction is what?
    more than 55%
  79. Increasing HR only “works” to increase CO up to a point. what happens if the rate increases too much?
    filling time is decreased => decrease in EDV and CO
  80. what affects heart rate
    • - autonomic innervation 
    • - hormones
  81. control of stroke volume: preload
    • – Frank-Starling Law of the Heart
    • – Increase EDV à increase force of contraction topump out “extra” blood
    • – INTRINSIC to cardiac muscle (do not need nerves or hormones)
  82. control of stroke: extrinsic
    • Changes in Sympathetic input (and contractility):
    • – Sympathetic stimulation (and adrenal medulla EPI) àincreased contractility à increased force of contraction(independent of EDV.)
  83. what does sympathetic stimulation do to systolic volume?
  84. Afterload
    • – Refers to back-pressure exerted by arterialblood – must be exceeded for ventricles toeject blood from heart.– With HYPERTENSION: afterload isincreased, affecting ESV (and loweringstroke volume)
    • • To compensate,heart must increase force ofcontraction à =>  damaging over long term!
  85. what is the mean pressure of the aorta
  86. main factors that affect cardiac output
    • - increase EDV
    • - increase in plasma epinephrine 
    • - increase activity of sympathetic nerves to heart
    • - decrease activity of parasympathetic nerves to heart
  87. cardiac output = ?
    stroke volume x heart rate