ecg changes in mi

1. USE OF
ECG IN MYOCARDIAL
INFARCTION
Mentor : Dr. Ayasha Shrestha
BY GROUP D
COMMUNITY MEDICINE DEPARTMENT

2. Electrocardiography (ECG)
 ECG is a record or graphical representation of electrical activities of heart which shows the
spread of electrical signals generated by SA node as it travels via atria then AV node,
bundle of His ,purkinje fibers and ventricles contract.
 Uses:-
1. Heart rate
2. Heart rhythm.
3. Abnormal electrical conduction.
4. Poor blood flow to the heart muscle.
5. Coronary artery disease.
6. Hypertrophy of heart chamber.

5. 12 LEADS OF ECG

6. USE OF ECG IN MYOCARDIAL INFARCTION
 Identification of the infract related artery.
 Electrocardiographic predictors of reperfusion.

7. IDENTIFICATION OF THE INFARCT RELATED ARTERY
The occlusion of right coronary artery is represented
by greater ST elevation in lead III than in lead II, and also
by ST segment depression in lead I and aVL.
 Also added finding of ST segment elevation in
lead V1 suggests proximal right coronary artery
occlusion associated with right ventricular infarction.
Similarly, ST elevation can be found in different leads
for different coronary artery occlusion.
However, it is limited for the individual with
preexisting coronary artery disease and coronary artery
bypass surgery.

8. ELECTROCARDIOGRAPHIC PREDICTORS OF REPERFUSION
Assessment of ST segment resolution is useful for
guiding reperfusion therapy.
The absence of ST segment resolution during the first
90 minutes after the fibrinolytic medications suggest
rescue angioplasty.
A reduction in ST segment elevation by more than 70
percent in the leads with maximal elevation indicates effective
ness of medications and control of disease.

9. ECG CHANGES IN MYOCARDIAL INFARCTION
 When a coronary artery is completely occluded, the following
sequence of ECG changes usually occurs unless the occluded
artery is immediately reperfused.
1. Peaked or hyperacute T waves.
2. Elevation of the ST segments.
3. Changes in the QRS complex with development of pathologic
Q waves or decrease in the size or amplitude of the R waves.
4. Inversion of T waves.

11. DIAGNOSIS OF MI (ECG FINDINGS )
 The hallmark of “acute myocardial infraction” is
1. Elevation of ST segment in the leads overlying the area
of infract.
2. Depression of ST segment in reciprocal lead.

12. REFERENCES
Textbook of physiology By Dr. A.K. JAIN
Guyton and Hall Textbook of medical physiology
The New England Journal of Medicine

13. CONTRIBUTIONS
GROUP MEMBERS NAME
 KREETIKA KOIRALA
 SONU KUMAR
 PRANISH LAMSAL
 KRISHA MAHARJAN
 SAMBRIDI MAHARJAN
 NIRANJAN MAHATO
 RITIKA MANANDHAR
 AADARSH MANDAL
 BHAVIYA MANDAL
 SATISH MANDAL
 DEEPA MEHTA
 UJJWAL MISHRA
 SANTOSH NEUPANE
 DIPISHA OLI

14. THANK YOU