Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CVPR 325 Diagnostic Procedures > Cardiac Biomarkers > Flashcards

Cardiac Biomarkers Flashcards

1
Q

a substance used as an indicator of a biologic state. It is a characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention.

A

A biomarker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

substances released from heart muscle when it is damaged as a result of myocardial infarction

A

Cardiac markers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

has been shown that cardiac markers can be released from cardiac tissue as a result of

A

damage from processes other than MI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

TRIAD Diagnosis of Acute Myocardial Infarction

A
  • Chest Pain: highly variable and subjective
  • ECG: Objective ST or T-wave changes
  • Biomarker elevations: Objective data defining ACS/AMI
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which Biomarkers?

A 
CK (CPK)
CK-MB
Troponin-I/T
LD (LDH)
Myoglobin
ALT/AST
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

1st Marker in response to AMI ?

0 - 1/2 day to be detected.

A

CK-MB isoforms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q 
2nd Marker(s) in response to AMI ?
1 day to be detected
A

CK-MB

Cardiac Troponin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The CK enzyme consists of two subunits

A

B (brain type) or M (muscle type), Making three different isoenzymes:

  1. ) CK-MM
  2. ) CK-BB and
  3. ) CK-MB
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Skeletal muscle expresses

A

CK-MM (98%) &

CK-MB (1%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The myocardium expresses

A

CK-MM (70%) &

CK-MB (30%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

CK therefore, lacks specificity for cardiac damage and needs to be augmented with ?

A

MB fraction and Relative Index (RI) to indicate true cardiac damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

(In cardiac as well as other tissues, phosphocreatine serves as

A

as an energy reservoir for the rapid regeneration of ATP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q 
Creatine kinase (CK/CPK) is an enzyme expressed in a number of tissues. 
How does it Function?
A

it catalyses the conversion of creatine to phosphocreatine degrading ATP to ADP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

CK Needs _______ increase with simultaneous increase in CK-MB to be diagnostic for MI

A

> two-fold

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

CK fluctuation in levels in regards to time?

A
  • Increases 4-6 hours after onset of MI
  • Peak activity is at 18 to 24 hours
  • Usually has returned to baseline levels by 36 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

False positive (for MI) CK elevation can be seen in:

A
  • Significant skeletal muscle injury
  • Significant CNS damage (Stroke/Trauma)
  • Occasionally from GI, renal, urologic disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

*elevations of CK secondary to non-cardiac causes have been noted to increase following a flatter curve

A

rising and disappearing at a slower pace that a cardiac source

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

CK-MB fluctuation in levels in regards to time?

A

Begins to rise 4-6 hours after onset of infarction
Peaks at about 12 hours
Returns to baseline at 24-36 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What enzyme has a High specificity for cardiac tissue damage?

A

CK-MB

20
Q

CK-MB Can be used to indicate early re-infarction if ?

A

level normalizes and then increases again

21
Q

False positive (for MI) CK-MB elevation can be seen in:

A

Significant skeletal muscle injury

  • Cardiac injury for reason other than MI
  • Cardioversion,
  • Defibrillation (ACLS CPR/ICD firing)
  • Blunt chest trauma (MVA/Sports injuries)
  • Cardiac AND non-cardiac surgical procedures
  • Cocaine abuse (vasospasm, tachycardia, - perfusion/demand mismatch)
  • Non often elevated in myocarditis, unless severe
22
Q

Cardiac specific forms of Troponins that are immunologically separable?

A 
Troponin T (TpnT)
Troponin I (TpnI)
23
Q
  • Regulatory proteins in striated muscle
  • Responsible for calcium-modulated interaction
  • Exist in a number of isoforms
A

Troponins

24
Q

Troponin is a complex

A

of three regulatory proteins that is integral to non-smooth muscle contraction in skeletal as well as cardiac muscle

25
Q

Troponin is attached to the

A

tropomyosin sitting in the groove between actin filaments in muscle tissue

26
Q

Troponin has three subunits,

A

TnC, TnT, & TnL

27
Q

Troponin-C binds to

A

calcium ions to produce a conformational change in TnI

28
Q

Troponin-T binds to

A

tropomyosin, interlocking them to form a troponin-tropomyosin complex

29
Q

Troponin-I binds to

A

actin in thin myofilaments to hold the troponin-tropomyosin complex in place

30
Q

Thus far, studies have failed to find a source of Troponin-I outside the heart, but have found some Troponin-T in skeletal muscle
Because of it’s increased specificity, our lab uses

A

Troponin-I

31
Q

heparin in blood sample can result in lowered values of what?

A

Troponin

32
Q

Troponin-I levels begin to rise

A

2-3 hours after onset of MI

33
Q

80% of patients with AMI will have positive values at

A

3 hrs

34
Q

Elevations in Troponin-I and Troponin-T can persist for up to

A

10 days after MI

35
Q

What is a good utility for retrospectively diagnosing an AMI ?

A

Troponin

36
Q

Remember, CK-MB returns to baseline by

A

48 hrs

37
Q

Troponin release can also be precipitated by

A

other conditions that cause myocardial damage

38
Q

Degree of elevation of Troponin value can give

A

prognostic information

39
Q

Some data suggest that the _______ peak TI value correlates with infarct size.

A

72-96 hour

40
Q

Used in the past along with aminotransferases to diagnose AMI. It is non-specific for cardiac tissue, which contains LD-1. However, pancreas, kidney, stomach tissue and red cells also contain LD-1

A

LDH

41
Q

In the setting of AMI, What is the LDH timing?

A

Onset: 6 - 12 hrs
Peaks: 24 - 48 hrs
Duration: 6 - 8 days

42
Q

Ubiquitous small-size heme protein released from all damaged tissues. Increases often occur more rapidly than TI and CK. Not utilized often for AMI/cardiac damage assessment because of its very rapid metabolism (short plasma half-life) causing short burst increases that are difficult to assess clinically, as well as its lack of specificity for cardiac tissue.

A

Myoglobin

43
Q

Used as surrogate markers of cellular damage in the past. Very non-specific so not used for assessment of myocardial damage any longer

A

ALT/AST

44
Q

H-FABP

A

Heart-type fatty acid binding protein

45
Q

The major protein responsible for O2 supply of striated

muscle.

A

Myoglobin

Early detectable, more sensitive but non-cardiospecific

CVPR 325 Diagnostic Procedures (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions