Card Set Information

2011-11-17 20:16:18
cv heart

cv heart
Show Answers:

  1. Is the central component of the cardiovascular system
  2. Propels blood through the blood vessels
  3. How many gallons of blood does the heart pump per year?
    Over 1 million gallons
  4. Where is the heart located?
    • In the mediastinum
    • -area from the sternum to the vertebral column and between the lungs
  5. Hollow, cone-shaped organ abou the size of a closed fist
  6. How much of the heart lies to the left of the body's midline?
  7. -dense irregular CT
    – protects and anchors the heart, prevents overstretchin
  8. – thin delicate membrane
    – contains:
    • parietal layer-outer layer
    • pericardial cavity with pericardial fluid
    • visceral layer (epicardium
  9. Layers of Heart Wall:
    • Epicardium– visceral layer of serous pericardium
  10. Layers of Heart Wall:
    – cardiac muscle layer is the bulk of the heart
  11. Layers of Heart Wall:
    – chamber lining, consists of connective tissue covered with endothelium
  12. Whar are the 4 chambers of the heart?
    • 2 upper atria
    • 2 lower ventricles
  13. Right Atrium & Great Vessels:
    What are the 3 sources of blood?
    • 1. Superior vena cava
    • 2. Inferior vena cava
    • 3. Coronary sinus
  14. What partitions the right atrium?
    Interatrial septum
  15. Right Atrium & Great Vessels:
    – Blood flows into right ventricle
    – has three cusps composed of dense CT covered by endocardium
    Tricuspid valve (atrioventricular valve)
  16. Forms most of anterior surface of heart
    Right ventricle
  17. Right ventricle:
    What partitions ventricles?
    Interventricular septum
  18. Right Ventricle:
    Blood flows into pulmonary trunk, also known assemilunar valve (three cusps each shaped like half moon)
    Pulmonary valve
  19. Forms most of the base of the heart• Receives blood from lungs - 4 pulmonary veins (2 right + 2 left)
    Left Atrium
  20. Left Atrium:
    Blood passes through into left ventricle– has two cusps (looks like Pope’s hat – Mitral valve)
    Bicuspid valve
  21. Forms the apex of heart
    Left Ventricle
  22. Left Ventricle:
    – blood passes through valve into the ascending aorta
    – just above valve are the openings to the coronary arteries
    Aortic valve (semilunar valve)
  23. Thickness of __________ varies according to the function of the chamber
  24. Myocardial Thickness and Function:
    thin walled, deliver blood to adjacent ventricle
  25. Myocardial Thickness and Function:
    Ventricle walls are much ________ and stronger
  26. Myocardial Thickness and Function:
    Supplies blood to the lungs (little flow resistance)
    Right ventricle
  27. Myocardial Thickness and Function:
    wall is the thickest to supply systemic circulation
    left ventricle wall
  28. Close preventing backflow of blood into atria
    – occurs when ventricles contract, pushing valve cusps closed
    A-V valves (Atrioventricular Valves)
  29. Open with ventricular contraction– allow blood to flow into pulmonary trunk and aorta
    Semilunar Valves
  30. Valves that close with ventricular relaxation– prevents blood from returning to ventricles, blood fills valve cusps, tightly closing the valves
    Semilunar valves
  31. What type of circuits are there for blood circulation?
    Two closed circuits, the systemic and pulmonary
  32. – left side of heart pumps blood through body
    – left ventricle pumps oxygenated blood into aorta
    – aorta branches into many arteries that travel to organs
    – arteries branch into many arterioles in tissue
    – arterioles branch into thin-walled capillaries forexchange of gases and nutrients
    – deoxygenated blood begins its return in venules
    – venules merge into veins and return to right atrium
    Systemic circulation
  33. – right side of heart pumps deoxygenated blood to lungs
    – right ventricle pumps blood to pulmonary trunk
    – pulmonary trunk branches into pulmonary arteries
    – pulmonary arteries carry blood to lungs for exchange of gases
    – oxygenated blood returns to heart in pulmonary veins
    Pulmonary circulation
  34. Blood supply to the heart
    Coronary circulation
  35. a very active muscle needs lots of O2
  36. Connections between arteries supplying blood to the same region, provide alternate routes if one arterybecomes occluded
  37. • First branches off aorta
    • Left coronary artery
    • Right coronary artery
    Coronary arteries
  38. Conduction System of Heart:
    – cluster of cells in wall of Rt. Atria
    – begins heart activity that spreads to both atria (contract simultaneously)
    – contraction of all muscle fibers is assisted by presence of “intercalated discs” (gap junctions)
    – excitation spreads to AV nod
    Sinoatrial (SA) node
  39. Conduction System of Heart:
    – Cells in wall (septum) between two atria adjacent to the ventricles
    – Fires slower than SA node (allow for emptying of atria
    Atrioventricular (AV) node
  40. Conduction System of Heart:
    Signal travels from AV node along AV bundle (bundle of His) to the ventricle
    AV Bundle (bundle of His)
  41. Conduction System of Heart:
    Signal branches into the right and left bundle branches in the interventricular septum
    Right and left bundle branches
  42. Conduction System of Heart
    - conduct signals from bundle branches throughout the ventricular myocardium
    Conduction myofibers (Purkinje fibers)
  43. – Action potentials of all active cells can be detected and recorded
  44. atrial depolarization
    P wave
  45. Conduction time from atrial to ventricular excitation
    P to Q interval
  46. Ventricular depolarization
    QRS complex
  47. – ventricular repolarization
    – atrial repolarization wave is hidden by QRS wave
    T wave
  48. Stethoscope
    Sounds of heartbeat are from turbulence in blood flow caused by valve closure
  49. – first heart sound (_____) is created with the closing of the atrioventricular valves
    – second heart sound (_____) is created with the closing of semilunar valves
    – contraction of heart chambers is called systole and relaxation is called diastol
    lubb; dupp
  50. Regulation of Heart Rate:
    Nervous control from the cardiovascular center in the ________
  51. Increases heart rate and force of contraction
    Sympathetic impulses
  52. Impulses decrease heart rate
    Parasympathetic impulses
  53. (pressure receptors, located in the arch of the aorta and carotid arteries) detect change in BP and send info to the cardiovascular center in the brain stem
  54. Affected by hormones
    – epinephrine, norepinephrine, thyroid hormones
    – ions (Na+, K+, Ca2+)
    – age, gender, physical fitness, and temperature
    Heart rate
  55. Heart muscle receiving insufficient blood supply
    – narrowing of vessels---, artery spasm or clot
    – smooth muscle & fatty deposits in walls of arteries
    Treatment– drugs, bypass graft, angioplasty, stent
    Coronary Artery Disease
  56. – death of area of heart muscle from lack of O2
    – replaced with scar tissue
    – results depend on size & location of damage
    MI = myocardial infarction
  57. – use clot dissolving drugs streptokinase or t-PA & heparin
    – balloon angioplast
    Blood clot
  58. Heart pain from ischemia of cardiac muscle
    Angina pectoris