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Myocardial InfarctionMyocardial Infarction

• Introduction

• PATHOPHYSIOLOGYPATHOPHYSIOLOGY

• Causes

• Clinical manifestation

• Dignostic evaluation

• Medical management

• Complication

• Nursing process

Outlines

Introduction

• Myocardial Infraction (MI): Is the term used to describe irreversible myocardial necrosis (cell death) that result from an abrupt decrease or total cessation of coronary blood flow to a specific area of the myocardium

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PATHOPHYSIOLOGYPATHOPHYSIOLOGY

• Inflammation Inflammation

• Plaque rupture Plaque rupture

• Thrombus formation Thrombus formation

• Irreversible damage starts in 20 to 40 minutes. Irreversible damage starts in 20 to 40 minutes. This process will continue for several hoursThis process will continue for several hours

causes• Atherosclerosis

• Hypertension

• Smoking

• Use of oral contraceptive

Clinical manifestation

• Sudden chest pain over the lower sternal region and upper abdomen is the presenting symptoms

• Pain increased to reach the level of heavy rise like pain which may radiate to shoulders and down the arm (usually left arm)

Clinical manifestation

• The pain begins spontaneously

• The pain is accompanied by SOB,pallor

• dizziness, nausea and vomiting

Diagnostic evaluation

• History

• ECG

• Echocardiogram

• Serial enzyme studies include CK,LDH,troponin

Medical managment1. Pharmacotherapy

• vasodilators: to treat myocardial pain as nitroglycerine

• Anticoagulants : as heparin

• Thrombolytics : use to dissolve any thrombus as streptokinase

Medical managment

2 Oxygen therapy

3 Analgesics: as morphin

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• Initial treatment:Initial treatment:

MONA greets all patients.MONA greets all patients.

a.a. M= MorphineM= Morphine========

2-4mg q 5-15 min slow IV.2-4mg q 5-15 min slow IV.

Maintain BP more than 90 mmHg.Maintain BP more than 90 mmHg.

Relief pain.Relief pain.

Reduce PVR & work load on the heart.Reduce PVR & work load on the heart.

b. b. A=Aspirin (A=Aspirin (160-325mg) PO.160-325mg) PO.

Chewed & swallowed if possible.Chewed & swallowed if possible.

Determine if hypersensitive to ASA.Determine if hypersensitive to ASA.

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• N= NitroglycerineN= Nitroglycerine SL for the 1 SL for the 1stst 24 hrs. 24 hrs.

• O= OxygenO= Oxygen via NC 2-5 L/M. via NC 2-5 L/M.

• Continuous cardiac monitoring.Continuous cardiac monitoring.

• Hematology, chemistry, & lipid profile.Hematology, chemistry, & lipid profile.

• X-ray, Echo… X-ray, Echo…

Care of MI patientsCare of MI patients

• bed rest with HOB elevated, beside commode.bed rest with HOB elevated, beside commode.

• Calm environment (limit stimuli & visitors, quite, Calm environment (limit stimuli & visitors, quite, calm environment).calm environment).

complication

• Dysrhythmias

• Acut pulmonary edma

• Congestive heart failure

• thromboembolism

Nursing procss

• Nursing diagnosis:

1. Chest pain R/T reduced coronary blood flow

2. Potential altered tissue perfusion R/T decreased cardiac output

3. Anxiety R/T fear of death

Nursing intervention

1. Relieving pain

2. Administer oxygen

3. Assess vital signs

4. Provide complete physical rest

5. Reduce anxiety

Anterior MIAnterior MI

V1, V2, V3, V4V1, V2, V3, V4 Anterior infarctAnterior infarct with ST elevationwith ST elevationLeft Anterior Descending Artery (LAD)Left Anterior Descending Artery (LAD)V1 and V2 may also indicate septal V1 and V2 may also indicate septal involvement which extends from front involvement which extends from front to the back of the heart along the to the back of the heart along the septumseptumAnterior septal MI most common type.Anterior septal MI most common type.Left bundle branch blockLeft bundle branch blockRight bundle branch blockRight bundle branch block2nd Degree Type22nd Degree Type2Complete Heart Block.Complete Heart Block.Reciprocal changes (II, III, aVF).Reciprocal changes (II, III, aVF).

Lateral MILateral MI

• I, AVL, V5, V6I, AVL, V5, V6– Lateral Infarction with ST elevationsLateral Infarction with ST elevations– Left Circumflex ArteryLeft Circumflex Artery– Rarely by itselfRarely by itself– Usually in combo.Usually in combo.– Reciprocal changes (II, III, aVF).Reciprocal changes (II, III, aVF).

Inferior MIInferior MI

leads leads II, III, AVFII, III, AVFInferior Infarct with ST elevationsInferior Infarct with ST elevationsRight Coronary Artery (RCA)Right Coronary Artery (RCA)1st degree Heart Block1st degree Heart Block2nd degree Type 1, 22nd degree Type 1, 23rd degree Block3rd degree BlockN/V common, BradyN/V common, Brady

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painpain

• Begin in center of chest & may radiated to Begin in center of chest & may radiated to shoulders, neck, jaw or arm.shoulders, neck, jaw or arm.

• Last more than 15-20 minutes and is not Last more than 15-20 minutes and is not relieved with rest or nitroglycerin.relieved with rest or nitroglycerin.

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Chest PainChest Pain

Anginal Pain:Anginal Pain:

a.a. Sudden associated e other factors.Sudden associated e other factors.

b.b. Squeezing, vice like.Squeezing, vice like.

c.c. Substernal, may radiated to back or arms.Substernal, may radiated to back or arms.

d.d. Usually lasts less than 15 min.Usually lasts less than 15 min.

e.e. Relieved with rest, nitrates, or oxygen.Relieved with rest, nitrates, or oxygen.

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Chest PainChest PainMI pain:MI pain:

a.a. sudden, without precipitating factors.sudden, without precipitating factors.

b.b. Intense, stabbing, vice like pressure, severe.Intense, stabbing, vice like pressure, severe.

c.c. Substernal, may radiate to back, arms, jaw, Substernal, may radiate to back, arms, jaw, neck.neck.

d.d. Last more than 30 min.Last more than 30 min.

e.e. Relieved with opioids.Relieved with opioids.

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Anterior MI Anterior MI

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Lateral MILateral MI

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Posterior MIPosterior MI

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Inferior MIInferior MI