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1. MYOCARDIAL INFARCTION
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2. Learning Outcomes
At the end of the lecture, student will be able to:
 Define acute myocardial infarction (AMI).
 State the etiology of AMI.
 Explain the pathophysiology of AMI
 State the clinical manifestations of AMI.
 State the diagnostic tests that helps to confirmed the
AMI.
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3. Cont. Learning Outcomes
At the end of the lecture, student will be able to:
 Explain the treatment and management for AMI.
 Explain the nursing management for patient with
AMI.
 Provide health teaching on preventive measures to
patients prior to discharge.
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4. The Heart
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5. Coronary Arteries
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6. Artery Wall

7. Acute Myocardial Infarction (AMI)
 Also called a heart attack.
 Defines as myocardial cell death due to
prolonged ischemia.
(Malaysian Heart Assoc, 2019).
 Myocardial injury is myocardial cell death due to
non ischemic causes.
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8. Cont..
 AMI is diagnosed by the rise and/fall in cardiac
troponins with at lease one value > 99 percentile
with accompanied with at lease one of the following:
 clinical history consistent with chest pain of
ischemic origin
 ECG changes
 imaging evidence of new loss of variable
myocardium
 identification of an intracoronary (IC) thrombus
by angioplasty
(Malaysian Heart Assoc, 2019).
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9. Cont.
 The main cause of AMI ---> sudden blockage
in the coronary artery ---> due to formation of
blood clot (thrombus) ---> causing irreversible
damage (necrosis) to the heart muscle.
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10. Types of AMI
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12. Pathophysiology
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Atherosclerosis Arterial Spasm
Atherosclerosis + Plaque
breaks + Thrombus
Gradual
Obstruction
Sudden Reversible
Obstruction
Sudden Irreversible
Occlusion
ISCHEMIA
Hypoxia
Reduced O2 demands Angina
Thrombolysis
Permanent Thrombolysis
Unstable Angina
Necrosis MI

13. Pathogenesis of MI
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 Myocardial necrosis begins within 20-30 minutes, mostly
starting at the sub-endocardial region (less perfuse, high
intramural pressure.
 Infarct reaches its full size within 3-6 hrs; during this
period, lysis of the thrombus by streptokinase or tPA
(tissue plasminogen activator), may limit the size of the
infarct.

14. Etiology & Risk Factors
 Most heart attack results from atherosclerosis
 Family history CAD
 Hypercholesterolemia
 ↑LDL ↓HDL
 ↑BP
 Obesity
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15. Cont.
 Limited physical activity
 Cigarette smoking
 Excessive alcohol intake
 Metabolic disorders
 Diet high in saturated fat, cholesterol &
calories
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16. Clinical Manifestations
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17. Different Location of Pain
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18. Cont.
 Fever
 Nausea & vomiting ---> results from
vasovagus reflexes.
 Crackles sound, peripheral edema & hepatic
enlargement ---> indicates cardiac failure.
 Cardiac vascular manifestations:
 elevated BP and HR
 BP may drop as decreased co and urinary output.
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19. Diagnostic Tests
 Clinical history consistent chest pain of ischemic
origin.
 Serum Troponin I or T
 Serum CK-MB (cretinine kinase-myocardial band)
 12-lead ECG (ST-T wave elevated by greater than
1 mm or > in two continuous leads ---> MI)
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20. Cont.
 Echocardiogram
 Serum potassium, magnesium & calcium
(imbalances & acidosis may cause change in
conduction & contractile).
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21. ECG Changes
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23. Pre-Hospital Management
 Patient with suspected ST segment elevation
MI (STEMI), should be given soluble or
chewable 300 mg aspirin and 300 mg
clopidogrel.
 These patient should be rapidly transported to
the hospital for early initiation of reperfusion
strategies.
 DO NOT BRING TO A CLINIC
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24. Treatment & Management
The goals of medical management are to:
 minimize myocardial damage, preserve myocardial
function and prevent complications lethal
dysrhythmias and cardiogenic shock:
1) Reperfusion – use of the percutaneous coronary
intervention (PCI) or thrombolytic medications.
2) Reduce myocardial oxygen demand & increase
oxygen supply with medications, oxygen therapy
& bed rest.
3) Coronary artery bypass or minimally invasive direct
coronary bypass (MIDCAB)
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25. Cont..
Pharmacological Therapy
 Nitrates (nitroglycerin) to increase oxygen supply
 Anticoagulants (aspirin, heparin)
 Analgesics (morphine sulfate)
 Angiotensin-converting enzyme inhibitors
 Beta blocker initially & a prescription to continue its
use after hospital discharge
 Thrombolytics (tPA, Activase) and reteplase (rPA,
TNKase) ---> must be administered after the onset of
symptoms, generally within 3-6hours
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26. 26

27. 27

28. Contraindication for Thrombolytic
Therapy
 Active Bleeding
 Known bleeding disorder
 History of hemorrhagic stroke
 Recent major surgery or trauma
 Uncontrolled hypertension, CVA
 Pregnancy

29. Potential Complications
 Acute pulmonary edema
 Heart failure
 Cardiogenic shock
 Dysrhythmias
 Cardiac arrest
 Pericardial effusion
 Cardiac tamponade
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30. Complications Post STEMI
 Important complications following STEMI:
 Arrhythmias
 Heart failure due to extensive myocardial damage or
mechanical complications.
 Chest pain post STEMI may be due to:
 reinfarction / recurrent MI
 post infarct angina
 pericarditis
 non cardiac causes such as gastritis (epigastric pain)
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31. Nursing Management
 Obtain baseline data on current status for
comparison with ongoing status include:
 history of chest pain or discomfort,
 dyspnea,
 palpitations,
 unusual fatigue,
 faintness (syncope) or
 diaphoresis.
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32. Cont..
1. Perform a complete physical assessment
---> for detecting complications & any change in
status. The examination include:
 Assess level of consciousness
 Evaluate chest pain (most important clinical
finding).
 Assess heart sound to detect an early sign of
impending LVF.
 Measure BP to determine response to pain &
treatment.
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33. Cont..
 Note narrowed pulse pressure after MI, suggesting
ineffective ventricular contraction.
 Assess bowel movement. Serve laxative to prevent
straining.
 Observe urinary output and check for edema; an
early sign of cardiogenic shock in hypotension with
oliguria.
 Examine IV lines and sites frequently.
2. Maintain CRIB
3. Assist in ADLs
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34. Nursing Diagnoses
1) Ineffective cardiac tissue perfusion related to
reduced coronary blood flow.
2) Risk for imbalanced fluid volume.
3) Risk for ineffective peripheral tissue perfusion
related to decreased cardiac output from left
ventricular dysfunction.
4) Death anxiety.
5) Deficient knowledge about post acute coronary
syndrome self-care.
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35. Nursing Interventions
Relieve sign & symptoms of ischemia.
 Administer oxygen to reduce pain associated with
low levels of circulating oxygen.
 Assess vital signs frequently to detect
hemodynamic changes.
 Position patient of Fowler’s position or put on
cardiac bed to decrease chest discomfort and
dyspnea.
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36. Cont…
Improving Respiratory Function
 Assess respiratory function to detect an early
signs of complications.
 Monitor fluid volume status to prevent
overloading the heart and lungs.
 Encourage patient to perform deep breathing
exercise and change position often to prevent
pooling fluid in lungs bases.
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37. Cont…
 Promoting Adequate Tissue Perfusion
 Maintain patient on bed rest
 rest to reduce myocardial oxygen consumption.
 Check skin temperature and peripheral pulses
frequently
 determine adequate tissue perfusion.
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38. Cont…
 Reduce Anxiety
 Develop a therapeutic relationship with patient.
 Allow patient to express feelings.
 Provide information to the patient and family in an
honest and supportive manner.
 Ensure a quiet environment, prevent interruptions that
disturb sleep.
 Use a caring and appropriate touch, relaxation
technique, and use humor.
 Provide spiritual support consistent with patient’s
beliefs.
 Provide divertional therapy.
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39. Health Teaching
 Compliance with prescribed medication.
 Adhere to the prescribed cardiac rehabilitation
regimen.
 Assist patient with scheduling & keeping follow up
appointments for monitoring, laboratory test, ECG
and general health screening.
 Advise family member to assist patient in adhere to
restrictions dietary advice.
 Instruct patient to monitor for sign of complications
and seek for medical attention immediately.
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40. Cont.
 Advice patient to change life styles:
 Stop smoking and alcohol intake
 Regular exercise as advised at lease 3 times a
week (cardio-exercise).
 Diet modifications
 Stress management
 Maintain ideal body weight
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41. References
 Amsterdam EA, Wenger NK, Brindis RG, et al. (2014).
AHA/ACC guideline for the management of patients with
non–ST-elevation acute coronary syndromes. J Am Coll
Cardiol. 2014;64(24):e139- 228. [PMID:25260718]
 Basavanthappa. B.T. (2015). Medical Surgical Nursing (3rd ed.).
New Delhi: Jaypee.
 Black, J. M., & Hawks, J. H. (2011). Medical Surgical Nursing.
(8th ed.). St. Louis, UK: Saunders.
 Ignatavicius, D. D., & Workman, M. L. (2016). Medical-Surgical
Nursing: Patient-Centered Collaboration Care. (8th ed.).
Singapore: Elsevier.
 https://www.malaysianheart.org/files/5cb6bf193304e.pdf
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42. Any Questions?
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