Chapter 11- Angina and Myocardial Infarction

med emergency- cardiovascular emergencies

1. Chapter 11 Angina Pectoris and Myocardial Infarction

2. Objectives Upon completion of this chapter, you will be able to: Name the major parts of the heart Explain how atherosclerosis affects the coronary arteries Describe the progression of coronary artery disease Define angina pectoris 2

3. Objectives (cont’d.) Explain the difference between stable and unstable angina List three precipitating factors of angina Describe the signs and symptoms of angina Explain how the dentist may diagnose angina Describe the treatment for angina 3

4. Objectives (cont’d.) List two side effects of nitroglycerin Define myocardial infarction Describe the signs and symptoms of myocardial infarction Describe the treatment for myocardial infarction 4

5. Objectives (cont’d.) Describe the two differences between angina and myocardial infarction Explain how stress is a precipitating factor of angina Explain what the dental team can do to prevent angina or myocardial infarction from occurring in the dental office 5

6. Anatomy of the Heart Four chambered, hollow muscular organ Pericardium: wall that encloses the heart Three layers: Epicardium (external layer) Myocardium (middle layer) Endocardium (inner layer) 6

7. Anatomy of the Heart (cont’d.) Figure 11-2: Anatomy of the human heart 7

8. Anatomy of the Heart (cont’d.) Four chambers: Atria: upper chambers Separated into right and left sides by the interatrial septum Ventricles: lower chambers Separated into right and left sides by the interventricular septum 8

9. Anatomy of the Heart (cont’d.) Right atrium receives blood from all tissues except for the lungs Blood then pumped to the right ventricle, where pulmonary artery exits and carries blood to the lungs Left atrium receives oxygenated blood from the lungs via pulmonary veins 9

10. Anatomy of the Heart (cont’d.) Left ventricle connected to the aorta and pumps blood to all the body except the lungs Two types of valves in the heart chambers: Atrioventricular valves Consist of the tricuspid and mitral valves Semilunar valves Consist of the pulmonary and aortic valves 10

11. Anatomy of the Heart (cont’d.) Heart muscle must receive an adequate supply of oxygenated blood Myocardium is supplied with blood by the first branches of the aorta Left coronary artery supplies blood to the left and right ventricles and left atrium Right coronary artery supplies blood to the left and right ventricles and the right atrium 11

12. Coronary Artery Disease Arteriosclerosis (hardening of the arteries) Artery walls become thickened and inelastic Atherosclerosis (form of arteriosclerosis) Affects the coronary arteries and causes coronary artery disease 12

13. Coronary Artery Disease (cont’d.) Degree of narrowing determines the adverse effects a patient experiences Angina pectoris Myocardial infarction 13

14. Angina Pectoris Latin phrase: “strangling of the chest” Episodes of pain when the heart experiences oxygen deficiency May be the first sign of atherosclerotic disease 14

15. Signs and Symptoms Pain: Usually in the substernal area of the chest Can be located anywhere in the chest from the epigastrium to the base of the neck May spread to the jaw and teeth Patient may describe as pressure/tightness 15

16. Signs and Symptoms (cont’d.) Duration of the pain important: Usually lasts three to five minutes if precipitating factors are removed Up to forty minutes if precipitating factors are not removed If episode continues longer, myocardial infarction should be considered 16

17. Signs and Symptoms (cont’d.) Physical signs are not very reliable Patient may: Appear pale or grey, with cold/clammy skin Experience a feeling of impending doom Pulse rate and blood pressure may increase slightly 17

18. Classifications of Angina Stable: Pain occurs from physical exertion or emotional upset Does not alter in frequency, duration, or intensity within a sixty-day period 18

19. Classifications of Angina (cont’d.) Unstable: Unpredictable; can occur even at rest Often increases in frequency, duration, and severity 19

20. Precipitating Factors of Angina Episodes Physical exertion Emotional stress Eating or drinking something cold Bathing Dressing Sexual activity Disturbing dreams 20

21. Diagnosis If patient experiences chest pain, dentist must try to diagnosis it Check medical history for cardiac problems Can ask the following questions: What type of discomfort are you experiencing? Where is the location of your discomfort? 21

22. Diagnosis (cont’d.) How long did your discomfort last? What preceded the discomfort? What provided relief? 22

23. Treatment Remain calm Stop all dental treatment Position the patient Administer nitroglycerin Administer oxygen 23

24. Treatment (cont’d.) Administer second dose of nitroglycerin, if needed Summon EMS if needed 24

25. Nitroglycerin Coronary vasodilator prescribed for the prevention or relief of angina Helps dilate the coronary arteries to allow more oxygenated blood to reach the heart Rapid action: within 90 seconds Side effects Orthostatic hypotension Severe headaches 25

26. Myocardial Infarction Occurs when a portion of the myocardium dies as a result of oxygen starvation caused by the narrowing or complete blockage of the artery Can occur in patients who have not experienced angina pectoris 26

27. Signs and Symptoms Compressing, squeezing pain usually begins in the substernal area and then spreads Pain may vary from severe to almost none Pain not relieved by nitroglycerin 27

28. Signs and Symptoms (cont’d.) Patient may have: Cold and clammy skin Vomiting, nausea, dizziness Hypotension Shortness of breath Sweating Weakness, extreme fatigue, anxiety Feeling of impending doom 28

29. Treatment Stop dental treatment Administer nitroglycerin Summon medical assistance if nitroglycerin does not relieve pain Keep patient quiet and calm 29

30. Treatment (cont’d.) Place the patient in whatever position is most comfortable Provide oxygen Be prepared to perform CPR 30

31. Differences between Angina and Myocardial Infarction The pain associated with myocardial infarction is: Greater in severity and duration Occurs in the absence of physical exertion or emotional stress Angina patient remains motionless 31

32. Differences between Angina and Myocardial Infarction (cont’d.) The myocardial infarction patient moves about trying to find a comfortable position 32

33. Stress Stress plays a major role as a precipitating factor of angina Chest discomfort from a stressful situation tends to last longer than that caused by physical exertion 33

34. Prevention Better to try to prevent an angina attack from occurring in the dental office than to have to treat an episode Angina can lead to myocardial infarction Be aware of the patient’s medical history 34

35. Prevention (cont’d.) Make visit as pain free as possible May be necessary to shorten the length of appointments 35

36. Summary Heart disease is the leading cause of death in the United States Dental team should do everything possible to alleviate undue stress Be aware of the signs, symptoms, and treatment for a cardiac emergency 36