Medical-Surgical Nursing: Myocardial
Infarction (MI)
1. Introduction
Myocardial Infarction (MI), commonly
known as a Heart Attack, occurs when
blood flow to the heart muscle is severely
reduced or cut off, leading to irreversible
cell death (necrosis).
2. Pathophysiology
Atherosclerosis (Plaque build-up)
\rightarrow Plaque Rupture \rightarrow
Thrombus (Clot) Formation \rightarrow
Complete Artery Occlusion \rightarrow
Myocardial Ischemia & Infarction.
3. Clinical Manifestations (What to look
for)
Chest Pain: "Crushing" or "Pressure"
sensation.
Radiation: Pain spreading to left arm, jaw,
neck, or back.
Autonomic Response: Diaphoresis (heavy
sweating), nausea, and vomiting.
Vital Signs: Tachycardia, hypertension
4. Diagnostic Evaluation (The Gold
(initially), or hypotension (in shock).
Standards)
ECG (12-Lead): * STEMI: ST-segment
elevation.
NSTEMI: ST-segment depression or
T-wave inversion.
Cardiac Biomarkers: * Troponin (I & T):
Most specific; rises within 3-4 hours.
CK-MB: Rises in 4-6 hours.
Echocardiogram: To assess wall motion
and Ejection Fraction.
Infarction (MI)
1. Introduction
Myocardial Infarction (MI), commonly
known as a Heart Attack, occurs when
blood flow to the heart muscle is severely
reduced or cut off, leading to irreversible
cell death (necrosis).
2. Pathophysiology
Atherosclerosis (Plaque build-up)
\rightarrow Plaque Rupture \rightarrow
Thrombus (Clot) Formation \rightarrow
Complete Artery Occlusion \rightarrow
Myocardial Ischemia & Infarction.
3. Clinical Manifestations (What to look
for)
Chest Pain: "Crushing" or "Pressure"
sensation.
Radiation: Pain spreading to left arm, jaw,
neck, or back.
Autonomic Response: Diaphoresis (heavy
sweating), nausea, and vomiting.
Vital Signs: Tachycardia, hypertension
4. Diagnostic Evaluation (The Gold
(initially), or hypotension (in shock).
Standards)
ECG (12-Lead): * STEMI: ST-segment
elevation.
NSTEMI: ST-segment depression or
T-wave inversion.
Cardiac Biomarkers: * Troponin (I & T):
Most specific; rises within 3-4 hours.
CK-MB: Rises in 4-6 hours.
Echocardiogram: To assess wall motion
and Ejection Fraction.
