Myocardial infarction, also known as a heart attack, occurs when blood supply to the heart is blocked, causing damage to heart muscle. It is usually caused by a blood clot forming at the site of a ruptured atherosclerotic plaque in one of the coronary arteries. This blockage damages heart tissue and reduces the heart's ability to contract. Symptoms include severe, prolonged chest pain, as well as other signs such as shortness of breath, sweating, and nausea. Diagnosis involves electrocardiograms, blood tests of cardiac enzymes, and imaging tests like echocardiograms. Treatment focuses on restoring blood flow, preventing further clots, and managing complications.

1. Myocardial infarction
By-kajal sansoya

2. What is MI ?
• Myocardial infraction is myocardial necrosis
occurring as a critical imbalance between
coronary blood supply & myocardial demand.
• Also known as heart attack
• It is a circulation problem, in which there is
blockage of blood supply to heart.

4. Etiology
• MI is usually due to the formation of an
occlusive thrombus at the site of rupture of an
atheromatous plaque in a coronary artery.
• Result of coronary artery blockage.
• Blockage may be caused by spasm of artery or
by atherosclerosis with acute clot formation.
• This blockage results in damaged tissues &
permanent loss of contraction of this portion
of heart muscle.

6. Clinical features
• Chest pain same as angina but is more severe and
prolonged.
• Pain is described as tightness, heaviness or
constriction.
• Pain is sever with pallor and peculiar facial
expression.
• Syncope
• Extreme tiredness.
• Vomiting
• breathlessness

7. Sings of MI
• Mild fever
• Pallor, sweating
• Narrow pulse pressure
• Raised JVP
• Tachycardia/ bradycardia
• Soft first heart sound
• Presence of 3 heart sound
• Systolic murmur

8. • Basal crepitations
• Pericardial friction rub
• arrhythmias

9. Complications
• Arrhythmias- sinus brdaycardia, sinus
tachycardia, atrial fibrillation, atrial
tachycardia, heart block.
• Cardiogenic shock- DM, hypertension, left
bundle branch block, previous history of MI.
• Cardiac failure
• Mitral regurgitation
• Pulmonary edema
• Murmur of VSD

10. • Cardiac temponade
• Cerebral and peripheral embolism
• DVT, pulmonary embolism
• Ventricular aneurysm
• Dressler’s syndrome- autoimmune reaction to
necrotic muscle, characterized by pain and
fever, pericaditis.

11. Investigations
• ECG- should be done within 10 min, changes
are seen in antero-septal, anterolateral,
inferior and posterior wall infarction.
• ST elevation, depression
• Left bundle branch block
• Appearance of pathologic Q wave
• In very early MI- T wave become tall and
peaked.

12. • Plasma enzymes- creatine kinease
• asparate aminotransferase
• lactate dehydrogenase
• Myoglobin
• troponins
• ESR, C-protein

13. • X-rays- enlarged heart.
• ECHO- regional wall motion abnormality and
ejection fraction.

14. Management
• Oxygen
• Nitrates
• Morphine
• Anti-platelets agents
• Beta-blockers
• Calcium channel blockers
• ACE-inhibitors
• Statins
• Thrombolytic therapy
• CABG

15. Points to remember
• Circulatory problem
• Caused by lifestyle factors, obesity
• Heart continuous beating
• Patient is conscious with pulse
• Symptoms include- chest pain, dizziness,
shortness of breath, sweating
• Treatment- medicine, surgery.

16. Quiz time
1. What do u think IHD and MI is same ?
o True
o False
2. What is major symptom for MI?
o angina
o Dysponea
o orthopnea

17. Thank you
Happy reading