Myocardial Infarction

  1. What is angina?
  2. What are risk factors that predispose a person to cardiac disease? (CAD, etc)
    • Elevated blood lipid levels
    • Smoking
    • HTN
    • DM
    • Obesity
    • Family History of premature cardiovascular disease (first degree relative with cardiovascular disease at 55 years old or younger)
    • Age - more than 45 years for men; more than 55 years for women
  3. What are nonmodifable risk factors for cardiac disease?
    • Family history of coronary heart disease
    • Increasing age
    • Gender (men develop CAD at an earlier age than women)
    • Race (higher incidence of heart disease in African Americans)
  4. What are modifiable risk factors for cardiac disease?
    • Hyperlipidemia
    • Cigarette smoking, tobacco use
    • HTN
    • DM
    • Lack of estrogen in women
    • OCP use
    • Obesity
    • Physical inactivity
  5. How does increased cholesterol contribute to cardiac disease?
    • Total Cholesterol
    • LDL - bad; when there is an excess of LDL, the LDL adheres to vulnerable points in arterial endothelium, where macrophages ingest them, leading to the formation of foam cells and the beginning of plaque formation
    • LESS THAN 160mg/dL in a normal person
    • LESS THAN 100mg/dL in a person with CAD
    • HDL - good; promotes the use of total cholesterol by transporting LDL to the liver, where it is biodegraded and then excreted
    • MORE THAN 40mg/dL ; preferably 60mg/dL
    • Triglycerides
  6. How to control cholesterol abnormalities to prevent cardiac disease?
    • Diet
    • Physical activity
    • Meds - STATINS
    • Soluble dietary fiber (fresh fruit, cereal grains, vegetables, and legumes)
  7. How do STATINS work?
    • 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors
    • Blocks cholesterol synthesis, lowers LDL and triglyceride levels, and increase HDL levels
    • Watch for: LIVER and Rhadomyalosis (check tests for skeletal function)
  8. What meds can you give for dyslipidemia?
    • STATINS
    • Nictonic Acids
    • Fibric Acids
    • Bile Acid Sequestrants
  9. What is angina?
    • Chest pain caused by myocardial ischemia due to inadequate myocardial blood and oxygen supply
    • Usually caused by atherosclerosis
    • Can range from: mild indigestion feeling to agonizing pain
    • Feels like: tightness, heavy, choking, or strangling that has a viselike quality
    • May radiate to: neck, shoulders, jaw, and inner aspects of the upper arm (USUALLY ON THE LEFT SIDE)
    • OTHER SYMPTOMS ASSOCIATED WITH THE CHEST PAIN/ANGINA: weakness or numbness in the arms, wrists, and hands, SOB, pallor, diaphoresis, dizziness, lightheadedness, and N/V, anxiety (FEELING OF IMPENDING DOOM)
  10. What factors can typically aggravate/precipitate angina?
    • Physical exertion
    • Exposure to cold
    • Eating a heavy meal
    • Stress / emotion-provoking situation
  11. What are the different types angina?
    • Stable - relieved with rest, nitro
    • Unstable - unrelieved with rest and nitro, pain consists for more than 15 minutes
    • Refractory - incapicating excruciating pain
    • Variant - pain at rest with ST-segment elevation; thought to be caused by coronary vasospasm
    • Silent ischmemia - objective evidence of ischemia (ECG changes with a stress test) but is asymptomatic
  12. What are the variations in angina pain?
    • Women - tends to present with fatigue
    • DM - tend to have dulled pain because of their peripheral neuropathy
  13. How do you assess and diagnose angina, MI?
    • Signs and symptoms - is the chest pain relieved with rest or meds? or not?
    • Patient history (PMH of CAD, family history)
    • ECG - T-wave inversion and ST-segment elevation are classic signs of MI; ST-segment elevation in 2 contiguous leads is a key diagnostic indicator for MI; Abnormal Q-waves
    • CBC
    • Echocardiogram - used to evalute ventricular function; used to ASSIST in dx; can detect hypokinetic and akinetic wall motion and can determine EF
    • Cardiac biomarkers labs - CKMB, Troponin, and Myoglobin
  14. How do you medically treat angina?
    • The objective is to decrease the oxygen demand of the myocardium and to increase the oxygen supply - through MEDS and CONTROL OF RISK FACTORS
    • First give - nitro - up to 3x - spaced 15 minutes apart
    • Second - give aspirin, rest
    • IF PAIN STILL CONTINUES AFTER 15 minutes - Call 911
  15. What are the pharmacologic therapies for angina, MI?
    • Nitroglycerin
    • Beta-blockers
    • Calcium channel blockers
    • Anti-platelet
    • Anti-coagulant
  16. In the ER, what is the medical treatment?
    • OXYGENATION - first
    • Nitro
    • Aspirin
    • Morphine
    • *Remember MONA
    • EKG
    • VS
  17. How does morphine work in the treatment of angina?
  18. What questions do you ask when you assess angina?
    • P - Where is the pain, can you point to it, what were you doing when the pain began?
    • Q - Could you please describe the pain, is like pain you've had before?
    • R - Can you feel the pain anywhere else, did anything make the pain better? (like nitro or rest)
    • S - How would you rate the pain on a scale from 0-10?
    • T - How long ago did the pain start?
  19. What is a myocardial infarction?
    • Occurs when myocardial tissue is abruptly or severely deprived of oxygen; ischemia can lead to necrosis of myocardial tissue if blood flow is not restored
    • Usually caused by an atherosclerotic plaque reducing blood flow in a coronary artery
    • Acute coronary syndrome - unstable angina --> MI - are the same process but at different points on the same continuum
    • The area of infarction develops over minutes to hours - as the cells are deprived of oxygen, ischemia develops, cellular injury occurs, and the lack of oxygen results in infarction (death of cells)
  20. What are the causes of MI?
    • Rupture of an atherosclerotic plaque that may become a thrombis and occlude the coronary artery *most common*
    • Vasospasm (sudden constriction or narrowing) of a coronary artery
    • Decreased oxygen supply (from acute blood loss, anemia, or low blood pressure)
    • Increased demand for oxygen (from increased heart rate, thyrotoxicosis, or ingestion of cocaine)
  21. What are the signs and symptoms of MI?
    • ANGINA (chest pain) that occurs suddenly and continues despite rest and nitroglycerin
    • SOB
    • Indigestion
    • Nausea
    • Anxiety
    • Cool, pale, moist skin
    • HR and RR - faster than normal
  22. How do you assess and diagnose MI?
    • Signs and symptoms
    • ECG - Twave inversion, ST-segment elevation (in two continuous leads), and development of an abnormal Q wave
    • Serial cardiac biomarkers
    • Health history - history of risk factors, family history
    • Echocardiogram - evaluates ventricular function; can detect hypokinetic and akinetic wall motion and EF
  23. What are the cardiac biomarkers related to MI?
    • Creatine Kinase of Heart Muscle - 72 hours
    • Troponin - must sensitive indicator of MI
    • Myoglobin

  24. What is acute coronary syndrome?
    The continuum of angina to MI; it is the essential the same process but on the same continuum
  25. What are the clinical manifestations of MI? ...How can you tell that your patient may be experiencing an MI?
    • CHEST PAIN (angina) - that occur suddenly and continues despite rest and medications
    • USUALLY a current comorbidity of CAD
    • SOB
    • Indigestion
    • N/A
    • Cool, pale, moist skin
    • HR, RR - may be slightly elevated
  26. What are the cardiac biomarker labs that are used to diagnose angina, MI?
    • Creatinine Kinase Heart Muscle - CKMB, a cardiac specific isoenzyme; increases when there is damage to the heart cells
    • Myoglobin - a heme protein that helps transport oxygen; increases when there is damage to cardiac and skeletal muscle (thus increased levels does not necessarily indicate MI); but negative results is helpful in excluding an MI dx
    • Troponin - a protein found in the myocardium; regulates the myocardial contractile process; an increase is detectable within a few hours of an acute MI; THE MOST HELPFUL INDICATOR FOR DXOF MI
  27. What is the medical management purpose/goal for MI?
    • Minimize myocardial damage
    • Preserve myocardial function
    • Prevent complications (i.e heart failure)
  28. After the patient comes in and you treat the angina, and they get diagnosed with acute MI. How do you medically treat it?
    • Thrombolytics - to dissolve and lyse the thrombus in the coronary artery (similar to what would be done for strokes); remember that the thrombolytic lyses the thrombus not the atherosclerotic plaque itself.
    • Analgesics - morphine sulfate - used to reduce pain and anxiety; but also reduces preload and afterload due to its vasodilating effects on the veins and the arteries respectively; MUST MONITOR BP and RR (BECAUSE BOTH CAN DANGEROUSLY DECREASE)
    • Ace-inhibitors - prevents the conversion of angiotensin I to II, then the BP decrease and the kidneys excrete sodium and fluid, decreasing oxygen demands on the heart. Do not give to a patient that is: hypotensive, hyponatremic, hypovolemic, or hyperkalemic
    • Emergenct PCI - an invasive procedure used to open the occluded artery; PCI treats the underlying atherosclerotic lesion
  29. What are the medical treatment guidelines for acute MI?
    • Use rapid transit to the hospital
    • Obtain 12-lead EKG within 10 minutes
    • Obtain cardiac biomarker labs
    • Obtain other diagnostics to clarify dx
    • Supplemental oxygen
    • Nitroglycerin
    • Morphine
    • Aspirin 162-325mg
    • Beta-blocker
    • Angiotensin-converting enzyme inhibitor within 24 hours
    • Evaluate for indications for reperfusion therapy: PCTA (percutaneous coronary intervention), thrombolytic therapy
    • Continue therapy as indicated: heparin, plavix, ticlid, glycoprotein IIb/IIIa inhibitor
    • Bed rest for a minimum of 12 to 24 hours
  30. What do you do after the acute MI phase, what do you do for cardiac rehabilitation?
    • A program that targets risk reduction by means of education, individual and group support, and physical inactivity
    • Goal: to extend life and improve the quality of life
    • How to accomplish goal: encouraging physical activity and physical conditioning, educating the patient and family, and providing counseling and behavioral interventions
    • Instruct patients to stop if: chest pain, SOB, dyspnea, weakness, fatigue, and palpitations
    • Patients who are able to walk 3-4 miles - can resume sexual activity
  31. What are the different phases of cardiac rehabilitation?
    • Phase I
    • Phase II - occurs after patient is d/c. Lasts 4-6 weeks; but can last up to 6 months. Focuses on lifestyle modification for risk factor modification for risk factor reduction. When planning goals - YOU ALWAYS ASK WHAT THE PATIENT WANTS TO WORK ON FIRST.
    • Phase III - focuses on maintaining cardiovascular stability and long-term conditioning
  32. What the nursing diagnosis for MI?
    • Ineffective cardiac perfusion related to reduced coronary blood flow from coronary thrombus and atherosclerotic plaque
    • Risk for imbalanced fluid volume
    • Risk for ineffective peripheral tissue perfusion related to decreased CO from left ventricular dysfunction
    • Death anxiety
    • Deficient knowledge about post-MI self-care
  33. What is typical of a cardiac diet?
    • Low sodium - may reduce extracellular volume, thus reducing preload and afterload, and thus myocardial oxygen consumption
    • Low calorie - esp. in the obese patient, weight reduction may decrease cardiac workload and improve tidal volume
  34. How to promote health after an MI?
    • Avoid any activity that causes CP, extreme dyspnea, or undue fatigue
    • Avoid extremes of hot or cold and walking against the wind
    • Losing weight - if indicated
    • Stop smoking and use of tobacco
    • Using personal strengths to support lifestyle changes
    • Developing heart-healthy eating patterns and avoiding large meals and hurrying while eating
    • Modifying meals to align with the therapeutic lifestyle changes (TLC) or the dietary approaches to stopping HTN (dash) diet
    • Avoiding activities that tense the muscles: isometric exercises, weight-lifting, any activity that requires sudden bursts of energy
    • Alternating activity with rest periods
    • Contact physican: SOB, fainting, slow or rapid HR, swelling of feet and ankles
  35. How does nitroglycerin work to treat angina?
    • A vasoactive agent
    • Reduces myocardial oxygen consumption, which decreases ischemia and relieves pain
    • PRIMARILY dilates the VEINS - causes venous pooling of blood throughout the body, which causes less return less blood return to the heart, and thus filling pressure (PRELOAD) is reduced
    • IN HIGHER DOSES dilates the arteries - causes a decrease in BP and thus decreases AFTERLOAD
    • Usually given sublingual - can tell it's working if you can feel tingling under the tongue
    • Don't exceed 3 doses - seperated by 4 minutes between each dose
  36. How do beta-adrenergic blockers work to treat angina?
    • Blocks beta-adrenergic sympathetic stimulation to the heart
    • Decreases HR, decreases BP, Decreases contractility, slowed conduction of impulses through through the conduction system
    • Doses can be titrated to reach: 50-60bpm
    • SE/contraindications: hypotension, bradycardia, advanced atrioventricular block, and decompensated HF
    • Monitor: ECG, BP, and HR after administration
    • Never give to pulmonary obstructive disease: ASTHMA, COPD
    • Other SE: depression, fatigue, decreased libido, and MASKS SYMPTOMS OF HYPOGLYCEMIA
    • Do not stop taking abruptly
    • IF DM - monitor glucose
  37. How do calcium channel blockers work to treat angina?
    • Decreases SA node automaticity
    • Decrease AV node conduction
    • Slows HR
    • Decreases the strength of heart contraction
    • Dilates smooth muscle wall of the coronary arterioles
    • Treats vasospasm
    • Caution: nifedipine
    • SE: hypotension, bradycardia, consptipation
  38. How do the antiplatelet and anticoagulant medications work to treat angina?
    they prevent platelet aggregation and subsequent thrombosis, which impedes blood flow
  39. How does aspirin work to treat angina?
    • Anti-platelet
    • Prevents platelet activation
    • Give 160-325mg dose of aspirin with as angina asap (ER or physicians office)
    • Continue even if they are taking other NSAIDs
    • SE: GI upset/ulcer/bleeding (usually give with PPI: pepcid, zantac, prilosec)
  40. How does plavis and ticlid work?
    • Similar to aspirin
    • Given if can't give aspirin
    • SE: same as aspirin, bleeding
  41. How does heparin work to treat angina?
    • Anti-coagulant
    • Prevents the formation of new blood clots
    • SE: bleeding
    • Amount given based on aPTT (activated partial prothrombin time): 2-2.5x the normal aPTT value
    • Monifor for signs and symptoms of internal bleeding: low BP, increased HR, decreased serum Hg/Hct
    • Implement bleeding precautions
    • HIT (heparin-induced thrombocytopenia): decrease in platelet count - may result in thrombosis
  42. How does oxygen work to treat angina?
    • Helps to keep the tissues oxygenated
    • ALWAYS REOXYGENATE FIRST
    • Pulsox : should be greater than 93%


Author
mmigue02
ID
62440
Card Set
Myocardial Infarction
Description
Myocardial Infarction
Updated