Focus on Coronary Artery Disease and Acute Coronary Syndrome

1. Focus onCoronary Artery Disease and Acute Coronary Syndrome (Relates to Chapter 34, “Nursing Management: Coronary Artery Disease and Acute Coronary Syndrome,” in the textbook)

2. Coronary Artery Disease and Acute Coronary Syndrome • A type of blood vessel disorder that is included in the general category of atherosclerosis • Begins as soft deposits of fat that harden with age • Referred to as “hardening of arteries”

3. Coronary Artery Disease and Acute Coronary Syndrome (Cont’d) • Cardiovascular diseases are the major cause of death in the United States • Heart attacks are still the leading cause of all cardiovascular disease deaths and deaths in general

4. Coronary Artery Disease Etiology and Pathophysiology • Atherosclerosis is the major cause of CAD • Characterized by a focal deposit of cholesterol and lipid, primarily within the intimal wall of the artery • Endothelial lining altered as a result of inflammation and injury

5. Risk Factors for CAD • Risk factors can be categorized as • Nonmodifiable risk factors • Age • Gender • Ethnicity • Family history • Genetic predisposition

6. Risk Factors for CAD (Cont’d) • Risk factors can be categorized as • Modifiable risk factors • Elevated serum lipids • Hypertension • Tobacco use • Physical inactivity • Obesity • Diabetes • Metabolic syndrome • Psychologic states

7. Risk Factors for CADHealth Promotion • Identification of people at high risk • Health history, including use of prescription/nonprescription medications • Presence of cardiovascular symptoms • Examples??? • Environmental patterns: diet, activity • Values and beliefs about health and illness • Why is this important?

8. Risk Factors for CADHealth Promotion (Cont’d) • Health-promoting behaviors • Physical fitness • 30 minutes >5 days/week • Regular physical activity contributes to: • Weight reduction • Reduction of >10% in systolic BP • In some men more than women, an increase in HDL cholesterol

9. Risk Factors for CADHealth Promotion (Cont’d) • Health-promoting behaviors • Nutritional therapy • ↓saturated fats • ↓cholesterol • ↑monounsaturated fats • Nuts, olive oil • ↑omega-3 fatty acids • ↑fruit and whole grains

10. Risk Factors for CADHealth Promotion (Cont’d) • Health-promoting behaviors • Cholesterol-lowering drug therapy • Drugs that restrict lipoprotein production: Statins, niacin • Drugs that increase lipoprotein removal: Bile acid sequestrants • Drugs that decrease cholesterol absorption: Ezetimibe (Zetia)

11. Cholesterol-lowering drug therapy • Statins • Serious side effects • Liver damage • Myopathy • Rhabdomyolysis

12. Cholesterol-lowering drug therapy • Nicotinic acid (niacin) • Flushing • Administer ASA 30-60 prior • GI disturbances • N/V/D

13. Cholesterol-lowering drug therapy • Bile acid sequestrants • GI disturbances • Bloating • Constipation • Dyspepsia • May interfere with absorption of other medications • Separate administration times

14. Risk Factors for CADHealth Promotion (Cont’d) • Health-promoting behaviors • Antiplatelet therapy • Aspirin • Inhibits activity of thromboxane A2 • Suppresses platelet aggregation • Clopidogrel (Plavix)

15. Gerontologic Considerations • Strategies to reduce risk factors are effective but often underprescribed • Necessary to modify guidelines for physical activity • Two points when elderly may consider lifestyle change(s) • When hospitalized • When symptoms result from CAD and not normal aging

16. Clinical Manifestations of CAD Chronic Stable Angina (Cont’d) • Intermittent chest pain that occurs over a long period with the same pattern of onset, duration, and intensity of symptoms

17. Clinical Manifestations of CAD Chronic Stable Angina • Etiology and pathophysiology • Reversible (temporary) myocardial ischemia = angina (chest pain) • O2 demand > O2 supply

18. Clinical Manifestations of CAD Chronic Stable Angina (Cont’d) • Etiology and pathophysiology • Primary reason for insufficient blood flow is narrowing of coronary arteries by atherosclerosis • For ischemia to occur, the artery is usually 75% or more stenosed

19. Clinical Manifestations of CAD Chronic Stable Angina (Cont’d) • Pain usually lasts 3 to 5 minutes • Subsides when the precipitating factor is relieved • Pain at rest is unusual • ECG reveals ST segment depression

20. Chronic Stable Angina Types of Angina • Silent ischemia • Up to 80% of patients with myocardial ischemia are asymptomatic • Associated with diabetes mellitus and hypertension • Confirmed by ECG changes

21. Chronic Stable AnginaTypes of Angina (Cont’d) • Prinzmetal’s (variant) angina • Occurs at rest usually in response to spasm of major coronary artery • Seen in patients with a history of migraine headaches and Raynaud’s phenomenon • Spasm may occur in the absence of CAD

22. Chronic Stable Angina Nursing and Collaborative Management • Drug therapy: Goal: ↓ O2 demand and/or ↑ O2 supply • Short-acting nitrates: Sublingual • Long-acting nitrates • Nitroglycerin ointment • Transdermal controlled-release nitroglycerin

23. Chronic Stable Angina Nursing and Collaborative Management (Cont’d) • Drug therapy: Goal: ↓ O2 demand and/or ↑ O2 supply • β-Adrenergic blockers • Calcium channel blockers • If β-adrenergic blockers are poorly tolerated, contraindicated, or do not control anginal symptoms • Used to manage Prinzmetal’s angina • Angiotensin-converting enzyme inhibitors

24. Chronic Stable AnginaNursing and Collaborative Management (Cont’d) • Diagnostic studies • Health history/physical examination • Laboratory studies • 12-lead ECG • Chest x-ray • Echocardiogram • Exercise stress test

25. Chronic Stable AnginaNursing and Collaborative Management (Cont’d) • Diagnostic studies • Cardiac catheterization • Diagnostic • Coronary revascularization: Percutaneous coronary intervention • Balloon angioplasty • Stent

26. Placement of aCoronary Artery Stent Fig. 34-9

27. Pre- and Post-PCIwith Stent Placement Fig. 34-10

28. Acute Coronary Syndrome • When ischemia is prolonged and not immediately reversible, acute coronary syndrome (ACS) develops • ACS encompasses: • Unstable angina (UA) • Non–ST-segment-elevation myocardial infarction (NSTEMI) • ST-segment-elevation myocardial infraction (STEMI)

29. Relationship Between CAD, Chronic Stable Angina, and ACS Fig. 34-11

30. Clinical Manifestations of ACS Unstable Angina • Unstable angina • New in onset • Occurs at rest • Has a worsening pattern • UA is unpredictable and represents a medical emergency

31. Clinical Manifestations of ACS Myocardial Infarction (MI) • Result of sustained ischemia (>20 minutes), causing irreversible myocardial cell death (necrosis) • Necrosis of entire thickness of myocardium takes 4 to 6 hours

32. Acute Myocardial Infarction Fig. 34-13

33. Clinical Manifestations of ACS Myocardial Infarction • The degree of altered function depends on the area of the heart involved and the size of the infarct • Contractile function of the heart is disrupted in areas of myocardial necrosis • Most MIs involve the left ventricle (LV)

34. Clinical Manifestations of ACS Myocardial Infarction • Pain • Total occlusion → anaerobic metabolism and lactic acid accumulation → severe, immobilizing chest pain not relieved by rest, position change, or nitrate administration

35. Clinical Manifestations of ACS Myocardial Infarction (Cont’d) • Pain • Described as heaviness, constriction, tightness, burning, pressure, or crushing • Common locations: substernal, retrosternal, or epigastric areas; pain may radiate

36. Possible Location of Chest Pain Fig. 34-7

37. Clinical Manifestations of ACS Myocardial Infarction (Cont’d) • Sympathetic nervous system stimulation results in • Release of glycogen • Diaphoresis • Vasoconstriction of peripheral blood vessels • Skin: ashen, clammy, and/or cool to touch

38. Clinical Manifestations of ACS Myocardial Infarction (Cont’d) • Cardiovascular • Initially, ↑ HR and BP, then ↓ BP (secondary to ↓ in CO) • Crackles • Jugular venous distention • Abnormal heart sounds • S3 or S4 • New murmur

39. Clinical Manifestations of ACS Myocardial Infarction (Cont’d) • Nausea and vomiting • Can result from reflex stimulation of the vomiting center by the severe pain • Fever • Systemic manifestation of the inflammatory process caused by cell death

40. Complications of Myocardial Infarction • Dysrhythmias • Most common complication • Present in 80% of MI patients • Most common cause of death in the prehospital period • Life-threatening dysrhythmias seen most often with anterior MI, heart failure, or shock

41. Complications of Myocardial Infarction (Cont’d) • Heart failure • A complication that occurs when the pumping power of the heart has diminished

42. Complications of Myocardial Infarction (Cont’d) • Cardiogenic shock • Occurs when inadequate oxygen and nutrients are supplied to the tissues because of severe LV failure • Requires aggressive management

43. Complications of Myocardial Infarction (Cont’d) • Papillary muscle dysfunction • Causes mitral valve regurgitation • Condition aggravates an already compromised LV • Ventricular aneurysm • Results when the infarcted myocardial wall becomes thinned and bulges out during contraction

44. Complications of Myocardial Infarction (Cont’d) • Acute pericarditis • An inflammation of visceral and/or parietal pericardium • May result in cardiac compression, ↓ LV filling and emptying, heart failure • Pericardial friction rub may be heard on auscultation • Chest pain different from MI pain • Worse when recumbent • Improves when leaning forward

45. Acute pericarditis

46. Diagnostic Studies Unstable Angina and Myocardial Infarction • Detailed health history and physical • 12-lead ECG: Changes in QRS complex, ST segment, and T wave can rule out or confirm UA or MI • Serum cardiac markers • Coronary angiography • Others: Exercise stress testing, echocardiogram

47. Collaborative CareAcute Coronary Syndrome • Emergency management • Initial interventions • ECG • MONA • Ongoing monitoring • Emergent PCI • Treatment of choice for confirmed MI • Balloon angioplasty + drug-eluting stent(s) • Ambulatory 24 hours after the procedure

48. Collaborative CareAcute Coronary Syndrome (Cont’d) • Fibrinolytic therapy • Indications and contraindications • Read these on your own • Marker of reperfusion: Return of ST segment to baseline • Rescue PCI if thrombolysis fails • Major complication: Bleeding

49. Collaborative CareAcute Coronary Syndrome (Cont’d) • Drug therapy • IV nitroglycerin • Morphine sulfate • β-adrenergic blockers • Angiotensin-converting enzyme inhibitors • Antidysrhythmia drugs • Cholesterol-lowering drugs • Stool softeners

50. Collaborative CareAcute Coronary Syndrome (Cont’d) • Nutritional therapy • Progress diet to • Low-salt • Low-saturated fat • Low-cholesterol