1. Thrombosis and Embolism

2. Thrombus Thrombus: a blood clot occurring in a vessel or the heart
A thrombus can occlude a vessel resulting in anoxic death of cells

3. ©

4. Infarction: tissue that has been starved of oxygen resulting in tissue death
What would you call heart tissue deprived of oxygen resulting in death?

5. Myocardial Infarction (heart attack)

6. Ischemia: tissue that has been starved of oxygen, but had not yet died
It is possible to reverse ischemia with clot dissolving drugs
Contains an enzyme that breaks down the clot

7. What is the difference between anoxia and infarction?
Anoxia is the term applied to cell death, infarction is the term applied to tissue death (many cells)

8. Thrombus

9. Embolus
Embolus: a blood clot that has ruptured or broken up and flows with the blood until it lodges or dissolves

10. Thrombus and Embolus ©http://www. nlm. nih

11. Embolism/Embolus ©http://images. healthcentersonline

12. How Does a Clot Form?

13. Steps of Thrombus Formation
1. Platelets stick together to plug the injured area.
Platelets: solid, circulating cell fragments that are vital to stopping bleeds

14. Platelets

15. 2. Clotting factors reinforce the platelets.
Proteins found in the blood that assist with coagulation

16. 3. Fibrin creates a mesh over the platelets that acts as a glue.

17. 4. Other cells also stick to the platelets to reinforce the damaged area.
Ex. Red and white blood cells

19. What Causes the Formation of a Thrombus?
1. Atherosclerosis

20. Blood clot surgery

21. Vascular injury: injury to the endothelium of a blood vessel can cause a clot
Why?

22. 2. Causes of Vascular Injury
Injury may be caused by phlebitis
Phlebitis: inflammation of veins caused by lack of blood flow
Multiple causes: chemical injury, traumatic injury, bacterial injury

23. Phlebitis

24. Blood flow: any change in blood flow bringing platelets into contact with the endothelial lining

25. 3. Blood Flow Changes
Major areas affected by blood flow that may result in a thrombus:
Plasmatic zone:
Along the tunica intima there is a layer of just plasma
Purpose: to keep solids from hitting the lumen’s wall
Why?

26. Provides a buffer so rbcs, wbcs, and platelets do not hit the wall

27. 3. Blood Flow Changes Valves
Large veins can become stretched out and not function properly
Stretched out valves cause turbulence of blood—not good

28. Thrombus Caused by a Valve ©http://myhealth. reidhosp

29. Varicose veins
Veins have become enlarged and twisted

30. Varicose Veins ©http://www. originmedical. co

31. Varicose Veins ©http://www. vascularweb

32. Hypercoagulability
Spontaneous blood clot
Reason is not always known

33. Location of Thrombi Can occur anywhere in the cardiovascular system
Mural thrombi: form in the heart
Occlusive thrombi: form in the lumen of the vessels

34. Treatment of Thrombi 1. Clot dissolving drugs
Break up the clot and, hopefully, prevent a myocardial infarction or stroke
Without the drugs:
Necrosis of the thrombus occurs (after several days)
Tissue damage will occur

35. Embolism
Embolism: the occlusion of a vessel by a foreign mass traveling through the blood system

36. Causes of Emboli Thrombus (main cause)
Undissolved air or gas bubbles in the blood stream
Tumor fragments
Bone fragments

37. Origin of Emboli
May arise in the veins or arteries

38. Venous Emboli Most arise from thrombi in the legs
Called deep vein thrombosis (if forms in the deeper veins of the legs or pelvis)
May cause warmth, swelling, pain near the affected vessels

39. Venous Emboli ©http://www.ismaap.org/uploads/pics/thrombose_bein.jpg

40. If the thrombus travel towards the heart:
Pass through the right side of the heart and into the lungs
Can occlude a vessel in the lungs resulting in pulmonary hemorrhage or pulmonary infarction

41. Pulmonary Embolism ©http://jaapa

42. Pulmonary Embolism ©http://radiology. muhealth

43. Animation of Embolus

44. Pulmonary Infarction Blood clot in the lungs
When no blood reaches a section of the lung, that portion of the lung suffers an infarct, meaning it dies because no blood or oxygen is reaching it

45. Arterial Emboli Usually form from thrombi in the aorta or heart
Travel away from the heart into smaller arteries

46. Arterial Embolism ©http://www. nlm. nih

47. Lab Aorta Clear ©http://www. tigerpath

48. For Lab ©http://www. panaceia-or-hygeia