Heart

Question 1

Natriuretic Peptides

Answer 1

generally function to inhibit the reabsorption of sodium in the renal tubule so that sodium excretion in urine is increased
ANP
BNP
CNP

Question 2

BNP

Answer 2

Brain Natriuretic peptide
first discovered in the Brain, but it is actually released from the ventricles when they stretch out.
BNPs cause vasorelaxation and increase water and sodium excretion
Used in diagnosis of CHF- strong correlation with Left Ventricular pressure
The higher the value, the more likely it is CHF or MI. Greater than 500 is essentially CHF.
Normal value less than 100pg/mL
(Don’t confuse with the BMP, basic metabolic panel)
Not a good tool if the patient is in renal failure

Question 3

CK

Answer 3

Creatine Kinase
an enzyme that helps convert creatine to phosphocreatine–> energy in stress situations
Mostly found in high energy tissues, Cardiac, skeletal muscle, brain
exists in 3 different isoenzymes

Question 4

CK-MM

Answer 4

found mostly in skeletal muscle- most CK is in this form

people with larger muscle mass tend to have higher baseline CK

Question 5

CK-BB

Answer 5

mostly in brain

Question 6

CK-MB

Answer 6

mostly in the heart
rises 3-6 hours after myocardial infarction, not elevated in all patients until 12 hours and returns to baseline in 36-48 hours
used to be the marker for MI, but we have better tests now. NOT the preferred test, but still sometimes gets ordered though!

Question 7

Troponins

Answer 7

the GOLD STANDARD for MI detection. It rises FASTER and stays around longer.

To diagnose acute coronary syndrome or myocardial injury

-When troponin is bound by calcium, it allows exposure of the myosin binding sites on actin.

• There are different troponin subsets: Cardiac troponin I used more commonly than T because renal failure more frequently increases Cardiac troponin T
  Troponin C is not used to detect MI

Question 8

Myoglobin

Answer 8

a relative of Hb, but is only in skeletal and cardiac muscle. It is a short term O2 storage in muscle.
-It only releases into bloodstream when there is a skeletal or cardiac injury
realeases w/in 3 hours.
More sensitive than CK-MB but is is not as specific to just cardiac

Question 9

LDH

Answer 9

Lactate dehydrogenase

catalyzes the conversion of lactate to pyruvate→ involved in energy production in cells

Not specific- in many tissues, but it is released during tissue injury.

There are 5 different isoenzymes, 1-5, and LDH-2 is the most abundant, EXCEPT in MI, then LDH-1 is more abundant

Not as useful as troponin, but the benefit is that it can be ordered 48 hrs after injury

Question 10

D-Dimer

Answer 10

a bi-product of clot formation. Generally it is non-detectable.
Increased D-Dimer is an indication of intravascular clotting. When you see this, ask yourself does this person have a clot somewhere?
DVT (deep vein thrombosis) or PE (pulmonary embolism)
should be used with other tests to diagnose DVT or PE

Question 11

CRP-HS

Answer 11

C-reactive protein is an acute phase reactant
can increased and then decrease a lot in cases of inflammation- an inflammatory mediator.
It is produced in the liver, but it is not specific. Often used to monitor a pt with strong hx of cardiovascular disease–> are they going down that path?

Question 12

Lipid panel

Answer 12

Useful in evaluating patients for hyperlipidemia, see if they have a risk for CHD

There is a linear relationship between CHD and hyperlipidemia!

Demonstrates which patients benefit from statin therapy, aspirin and other life-saving treatments

Question 13

LDL

Answer 13

Low density Lipoprotein- this is bad, you want it to be LOW. This carries a lot of cholesterol, 75%

Question 14

HDL

Answer 14

High density Lipoprotein, this is good, you want it to be HIGH. This carries less cholesterol, 25%, more protein in comparison to LDL.
Takes cholesterol back to the liver
Men at risk if below 40
Women at risk if below 50

Question 15

Who do we screen for lipid panel?

Answer 15

Men at age 35+ or if they have risk factors, or a family Hx
Women at 45+ (estrogen confounding factor),, or sooner if risk factors or family hx

Diabetics- annually
High risk patients with one or more, or one severe of: Smoking, Hypertension, Family Hx

Question 16

Total Cholesterol

Answer 16

sum of LDL, HDL and VLDL- want below 200

Question 17

Triglycerides

Answer 17

made in the liver, they are fatty acids and glycerol combined
these are an energy source for the body.
ideally, you want this below 150
diabetics frequently have high triglycerides, very high is over 500

Question 18

LDL particle testing

Answer 18

Calculates how many particles of LDL you have, and how big they are- the smaller and denser are more dangerous because they can attach to the arterial wall better.
More ideal, of your LDL, you want big and fluffy vs small and dense.
This is done via gel electrophoresis
Gone out of favor for testing because it is an added expense.

Question 19

CK normal

Answer 19

50-200 units/liter

Question 20

Total CK increase in

Answer 20

strenuous exercise
recent surgery
Rhahbdo

Question 21

Troponin I normal

Answer 21

Cardiac troponin I:

Question 22

Troponin T normal

Answer 22

Cardiac troponin T:

Question 23

D-Dimer normal

Answer 23

Normal value:

Question 24

Lipid panel components

Answer 24

Total cholesterol
Triglycerides
LDL
HDL

Question 25

Lipid panel guidelines

Answer 25

If initial test is clearly normal → test every five years
If initial test borderline → test every three years
In patients over age 65 who have had more than 1 screening in past, it is reasonable to stop screening.

Generally should be measured while fasting

Question 26

Triglycerides high in

Answer 26

Familial hypertriglyceridemia
Hyperlipidemia
High carbohydrate diet
Poorly controlled diabetes

Question 27

HDL high in

Answer 27

Familial HDL lipoproteinemia
Exercise
Moderate alcohol use
Healthier eating choices
Estrogen administration

Question 28

HDL low in

Answer 28

Metabolic syndrome

Genetically low HDL

Question 29

Friedewald formula

Answer 29

LDL calculation
LDL= Total cholesterol - (HDL+TG/5)
*only valid if TG, triglycerides, is below 400

Question 30

LDL levels

Answer 30

if you are already at risk for HD, you want this below 100

Greater than 160 is bad

Question 31

LDL high in

Answer 31

Familial LDL lipoproteinemia

Question 32

LDL low in

Answer 32

Exercise

Low fat diet

Question 33

LDL pattern A

Answer 33

Large particle size

Question 34

LDL pattern B

Answer 34

Small, dense particle size

Higher ability to enter walls of blood vessel and increased risk of CHD

Question 35

LDL pattern I

Answer 35

Intermediate particle size