MUSCLE INJURIES

Question 1

Myocardial infarction is diagnosed by the presence of 2 out of 3 features:

Answer 1

a. Chest pain
b. ECG changes
c. Cardiac enzymes

Question 2

• prolonged

Answer 2

Chest pain

Question 3

 most important condition
 heart attack
 decreased flow of blood in the heart causing damage to the
heart muscle
 major cause of morbidity in the US

Answer 3

Myocardial infarction

Question 4

Enzymes released from cells

Answer 4

AST, CK & LDH

Question 5

LDH ()

Answer 5

LD1 > LD2

Question 6

Enzyme leaks from cells after injury; half-life is about

Answer 6

4 hours

Question 7

longer during

Answer 7

renal dysfunction

Question 8

PROTEIN MARKERS

Question 9

Heme-containing protein that binds O2 with cardiac and skeletal muscle

Answer 9

Myoglobin

Question 10

Earliest marker in MI

Answer 10

Myoglobin

Question 11

Reasonable sensitivity but poor specificity for MI dx

Answer 11

Myoglobin

Question 12

Used in dx but not specific

Answer 12

Myoglobin

Question 13

Levels are related to muscle mass and activity

Answer 13

Myoglobin

Question 14

Bind O2 within cardiac and skeletal muscle

Answer 14

Troponin

Question 15

Govern excitation-contraction coupling

Answer 15

Troponin

Question 16

Troponin Three subunits:

Answer 16

o Troponin T (cTnT) - tropomyosin-binding unit
o Troponin C (TnC) - calcium-binding subunit
o Troponin I (cTnI) - inhibitory subunit (binds to actin)

Question 17

o Troponin T (cTnT) -

Answer 17

tropomyosin-binding unit

Question 18

o Troponin C (TnC) -

Answer 18

calcium-binding subunit

Question 19

o Troponin I (cTnI) -

Answer 19

inhibitory subunit

Question 20

(binds to actin)

Answer 20

cTnI

Question 21

are bound to muscle fibers

Answer 21

cTnT and cTnI

Question 22

cTnT and cTnI slowly released ((?)after MI)

Answer 22

1-2 weeks

Question 23

Essentially absent from normal serum

Answer 23

Troponin

Question 24

Troponin Highly sensitive assay:

Answer 24

0.1 ng/mL

Question 25

"gold standard" for diagnosis of MI Together w/ CK and LDH

Answer 25

Troponin

Question 26

Troponin Specimen of choice:

Answer 26

heparinized plasma samples

Question 27

Troponin False positive results:

Answer 27

Fibrin Rheumatoid Factor

Question 28

(incompletely clotted specimen) Adhere to walls of testing kits

Answer 28

Fibrin

Question 29

Risk factor for CVD

Answer 29

Rheumatoid Factor

Question 30

Involved in contraction and relaxation on the heart muscle

Answer 30

Troponin

Question 31

Troponin Location: (responsible for the excitation of the heart)

Answer 31

Actin and Tropomyosin

Question 32

Direct trauma

Answer 32

physical injury, surgery, strenuous exercise, or IM injection

Question 33

CK o Severe disorders caused by adverse effects that triggers dopamine receptors

Answer 33

Neuroleptic malignant syndrome

Question 34

CK

Answer 34

Direct trauma (physical injury, surgery, strenuous exercise, or IM injection) Neuroleptic malignant syndrome Chronic skeletal muscle damage

Question 35

Protein marker found in skeletal muscle and NOT found in cardiac muscle

Answer 35

Carbonic Anhydrase – III

Question 36

Type of muscle injury

Answer 36

RHABDOMYOLYSIS

Question 37

Caused by:

Answer 37

drugs (ethanol & cocaine), viral infections, extreme exertion, crush injuries, ischemia of lower extremities and inflammatory myopathies

Question 38

Higher total CK w/ myoglobinuria

Answer 38

RHABDOMYOLYSIS

Question 39

: release of cell contents (K+, PO5, and nucleotides)

Answer 39

"Cell lysis syndrome”

Question 40

Muscle fiber die causing release of cell contents ito the blood stream

Answer 40

RHABDOMYOLYSIS

Question 41

RHABDOMYOLYSIS Complication :

Answer 41

kidney / renal failure

Question 42

Kidney cannot process the contents of muscle fiber that passes through the glomerulus

Answer 42

RHABDOMYOLYSIS

Question 43

RHABDOMYOLYSIS TYPES

Answer 43

• Cardiac Muscle Injury (CMI), Skeletal Muscle Injury (SMI), Rhabdomyolysis (RML)

Question 44

Difficult to distinguish the two

Answer 44

Cardiac Muscle injury existing with Skeletal Muscle injury

Question 45

is the diagnostic test of choice for recognition of cardiac injury

Answer 45

Troponin

Question 46

↑ Total CK, AST, Myoglobin, Tropomin =

Answer 46

SMI and CMI

Question 47

↑ Total CK, AST, Myoglobin, Normal Troponin =

Answer 47

SMI

Question 48

↑ Myoglobin, CA-III =

Answer 48

SMI

Question 49

↑ Myoglobin and CA - III =

Answer 49

SMI

Question 50

↑CA-III=

Answer 50

SMI

Question 51

↑ Tropomin =

Answer 51

SMI

Question 52

↑ CK, AST, Myoglobinuria =

Answer 52

RML

Question 53

↑ Myoglobin =

Answer 53

RML