L4: IHD - MI (Pt 2)

Question 1

INVx in Acute MI

Answer 1

Question 2

INVx in Acute MI

• Cardiac Enzymes

Answer 2

Question 2

Cardiac Enzymes in Acute MI

• CK

Answer 2

Question 3

Cardiac Enzymes in Acute MI

• CK-MB

Answer 3

Question 4

Cardiac Enzymes in Acute MI

• LDH

Answer 4

Question 5

Cardiac Enzymes in Acute MI

• cTnT, cTnI

Answer 5

Question 6

Cardiac Enzymes in Acute MI

• Myoglobin

Answer 6

Question 7

Cardiac Enzymes in Acute MI

• Pathophysiology

Answer 7

Cardiac enzymes are released into blood from necrotic heart muscle after an acute MI.

Question 8

Cardiac Enzymes in Acute MI

• Type of Measurment

Answer 8

• Serial measurements of cardiac markers are essential.

Question 9

Cardiac Enzymes in Acute MI

• Early Dx?

Answer 9

• Ck-MB, cnT, or cTl are used for early diagnosis of AMI (3-6h) as a definitive marker.
• Recent data utilizing (HS-CTnT) assays allow diagnosis of most cases of AM/ within 1-3 hours of presentation and thus the use of other markers is rarely mandatory

Question 10

Cardiac Enzymes in Acute MI

• HS-cTnT

Answer 10

• Ck-MB, cnT, or cTl are used for early diagnosis of AMI (3-6h) as a definitive marker.
• Recent data utilizing (HS-CTnT) assays allow diagnosis of most cases of AM/ within 1-3 hours of presentation and thus the use of other markers is rarely mandatory

Question 11

Def of CK

Answer 11

• CK is an enzyme present in high activity in cardiac muscle, skeletal muscle and brain tissue.
• It is not specific for myocardium

Question 12

Types lof CK

Answer 12

Question 13

Significance of CK in MI

Answer 13

Question 14

Types of Cardiac Troponins

Answer 14

Question 15

What is Troponin C?

Answer 15

calcium-binding component

Question 16

Distribution of Troponin C

Answer 16

identical in the skeletal and cardiac muscle

Question 17

Significanc of Troponin C in MI

Answer 17

so, troponia C is not specific for myocardial injury

Question 18

Function of Troponin I

Answer 18

prevents myosin from binding to actin in relaxed muscle

Question 18

Significance of Troponin I in MI

Answer 18

Question 19

Advantages of HS-cTnT in MI

Answer 19

Question 20

Cardiac Troponins

• Significance of Troponin T & Troponin I

Answer 20

Question 21

• However elevated levels of cInT, could be seen in some cases of CRF and myopathy.
• (In such cases the elevated levels are sustained while in AMI there is rise and fall of cTnT levels).

Answer 21

….

Question 22

the only disadvantage of cardiac troponin is …..

Answer 22

• the late clearance (7-10 days) that makes it difficult to identify a recurrent myocardial infarction. (CK-MB returns to normal by 24 to 36 hours).

Question 23

Delta troponin

Answer 23

Question 24

ECG in **Acute MI**

Answer 24

Question 25

ECG in **Acute MI** - ST Segment

Answer 25

Question 26

ECG in **Acute MI** - T Wave

Answer 26

Question 27

ECG in **Acute MI** - Pathological Q

Answer 27

Question 28

Pathologic Q waves are defined as .......

Answer 28

as duration >0.04 s or >25% of R-wave amplitude)

Question 29

The first change ECG change during STEMI is .......

Answer 29

Question 30

The ECG may be normal during the first few hours of infarction.

Answer 30

....

Question 31

In old MI: The only residual change is the ......

Answer 31

Pathological Q Wave

Question 32

site of infarction as regard to ECG

Answer 32

Question 33

site of infarction as regard to ECG - Anterior MI

Answer 33

Question 34

site of infarction as regard to ECG - Lateral MI

Answer 34

Question 35

site of infarction as regard to ECG - Inferior MI

Answer 35

Question 36

INVx in **Acute MI** - ECHO & Dubutamine ECHO

Answer 36

- Ventricular wall motion abnormalities. - Complications: MR, myocardial aneurysm

Question 37

INVx in **Acute MI** - Nuclear Imaging

Answer 37

- Radioactive Thallium 201, or technetium 99 m) - Thallium 201: is taken up by healthy myocardium & not by ischemic myocardium (cold spot)

Question 37

INVx in **Acute MI** - Coronary Angiography

Answer 37

- reveals which vessels have been affected and the extent of damage

Question 38

INVx in **Acute MI** - Lab INVx

Answer 38

* Leukocytosis. * Increased ESR: as there is tissue damage.

Question 39

TTT of **Acute MI**

Answer 39

Question 40

TTT of **Acute MI** - Prehospital

Answer 40

Question 40

TTT of **Acute MI** - Hospital

Answer 40

Question 41

Hospital TTT of **Acute MI** - General

Answer 41

Question 42

Hospital TTT of **Acute MI** - Relieve Chest Pain

Answer 42

Question 43

Hospital TTT of **Acute MI** - Thrombolytic Therapy

Answer 43

Question 44

Thrombolytic Therapy as Hospital TTT of **Acute MI** - Timing

Answer 44

- The earlier that thrombolytlc therapy Is given after the onset of chest pain, the greater the benefit (thrombolytic therapy Is beneficial up to 12 hours)

Question 45

Thrombolytic Therapy as Hospital TTT of **Acute MI** - Drugs

Answer 45

Question 46

Thrombolytic Therapy as Hospital TTT of **Acute MI** - NB

Answer 46

Question 47

Thrombolytic Therapy as Hospital TTT of **Acute MI** - Absolute CI

Answer 47

Question 48

Thrombolytic Therapy as Hospital TTT of **Acute MI** - Relative CI

Answer 48

Question 49

Coronary Revascularization as Hospital TTT of **Acute MI**

Answer 49

Question 50

Coronary Revascularization as Hospital TTT of **Acute MI** - PCI

Answer 50

Question 51

Coronary Revascularization as Hospital TTT of **Acute MI** - CABG

Answer 51

Question 52

TTT of Acute MI - Timeline

Answer 52

Question 53

Hospital TTT of **Acute MI** - TTT of Early Complications

Answer 53

1. Acute heart failure. 2. Arrhythmia. 3. Cardiogenic shock

Question 54

TTT of **Acute MI** - Post-Hospital

Answer 54

Question 55

Markers of Opening up of Infarct Related Artery

Answer 55

1. Prompt and persistent relief of chest pain. 2. ST resolution within 120 minutes. 3. Arrhythmias such as accelerated idio-ventricular rhythm.

Question 56

Diagnosis of MI (In Brief)

Answer 56

at least 2 of the following - classic chest pain - ECG changes - Positive biomarkers ( cardiac enzymes)