14. Cardiac Disease and Markers

Question 1

ECG checks for what 5 things?

Answer 1

1. Rate
2. Rhythm
3. Axis
4. Hypertrophy
5. Infarction

Question 2

Drug that controls arrhythmias?

Answer 2

Digoxin

Question 3

Main cause of cardiac ischemia?

Answer 3

Coronary atherosclerosis

Question 4

Caused by hemolytic streptococcus induced immune reaction

Answer 4

Valvular disease

Question 5

CKMB relative index indicating myocardial damage?

Answer 5

> 3%

Question 6

CKMB relative index indicating skeletal muscle damage?

Answer 6

< 3%

Question 7

CKMB relative index formula

Answer 7

(CKMB/Total CK) * 100%

Question 8

BNP stimulus release

Answer 8

Ventricular stretch and increased volume

Question 9

3 reasons for increased CK?

Answer 9

• Myocardial diseases (AMI)
• Skeletal muscle disease/injury (alcohol abuse)
• Cerebral injury, meningitis

Question 10

2 methodologies for CKMB?

Answer 10

• Enzyme immunoassay

- Electrophoresis

Question 11

Troponin methodology?

Answer 11

Chemiluminescence sandwich antibody assay

Question 12

Troponin rise, peak, fall window

Answer 12

4-6 hrs
12-24 hrs
By 7 days

Question 13

Troponin RI

Answer 13

< 0.04 ug/L

Question 14

Troponin range indicating possible MI, repeat in 6-8 hrs?

Answer 14

0.05 - 0.49 ug/L

Question 15

Myoglobin rise, peak, fall window

Answer 15

1-4 hrs
8-12 hrs
24 hrs

Question 16

CK rise, peak, fall window

Answer 16

4-6 hrs
12-24 hrs
48 hrs

Question 17

Sac around heart that anchors it to diaphragm

Answer 17

Pericardium

Question 18

6 properties of an ideal cardiac marker

Answer 18

• Specific for myocardial injury
• Sensitive to small injuries
• Rapidly released following injury
• Around long enough in blood to permit diagnosis
• Produce blood levels proportional to infarct size
• Be technically easy to assay

Question 19

Negative predictor of myocardial damage

Answer 19

Myoglobin

Question 20

Lactate dehydrogenase rise, peak, fall window

Answer 20

36-48 hrs
72 hrs
7-12 days

Question 21

Effects of BNP on blood vessels

Answer 21

Vasodilation

Question 22

Which troponin unit is most specific for cardiac

Answer 22

Troponin I

Question 23

Which troponin unit peaks soonest in myocardial damage

Answer 23

Troponin I

Question 24

Which troponin unit remains high the longest

Answer 24

Troponin T

Question 25

Normal levels of _________ and _________ rules out heart failure

Answer 25

BNP, NT-proBNP

Question 26

How does homocysteine cause atherosclerosis

Answer 26

It damages inner lining of arteries = promotes clots

Also degrades, inhibits formation of structural components of arteries (collagen, elastin)