-
Congestive heart failure
- a)
- Heart unable to pump blood effectively
- i)
- Narrowed arteries (coronary artery disease)
- ii)
- Past MI with scar tissue interference
iii) Arrhythmias
- vi) Primary
- disease of heart itself (cardiomyopathy)
- vii) Congenital
- heart defects
- viii)
- Infection of valve or muscle tissue
- (endocarditis or myocarditis)
- b)
- Fluid build up in chest and throughout body
- (2) Slow
- circulation diminishes renal function which cause the accumulation of water and
- waste
- c)
- Fatigue, labored breathing, dizziness, chest
- pain, loss of consciousness
- d)
- Contributing factors hypertension,
- Anemia/polycythemia, endocrine disorders, malnutrition, drug/alcohol toxicity,
- abesity, pulmonary disease.
-
BNP
- a)
- Hormone secreted primarily by the ventricles in
- response to excessive stretching of the heart muscle
- i)
- Acts on kidneys to increase fluid excretion
- b)
- COPD (chronic obstructive pulmonary disease)
- will not increase affect BNC concentration
- d)
- elevation of conc.=elevation of stage=more
- severe CHF
-
ischemic heart disease
- a)
- restricted blood flow in the heart muscle,
- causing lack of oxygen to one area causing heart pain
Causes
- i)
- Atherosclerosis = thickening or hardening of
- artery wall due to calcified cholesterol/lipid plaque in the lining
- ii)
- Thrombosis = presence of blood clot in vascular
- system
- iii) Embolism
- = sudden blockage of blood vessel
- i)
- Chest pain, labored breathing, loss of
- consciousness and angina
- ii)
- Angina = sudden chest pain due to inadequate
- perfusion of heart muscle
-
acute myocardial infarction (AMI)
= sudden deprivation in circulating blood and oxygen to heart muscle
- a)
- if blood flow stopped completely, cell death or
- necrosis will occur resulting in acute myocardial infarction (AMI)
- i)
- Atherosclerosis = thickening or hardening of
- artery wall due to calcified cholesterol/lipid plaque in the lining
- ii)
- Thrombosis = presence of blood clot in vascular
- system
- iii) Embolism
- = sudden blockage of blood vessel
-
Angina
sudden chest pain due to inadequate perfusion of heart muscle
-
Troponin
- ii)
- TnI = inhibitory component
- iii) TnT
- = tropomysin-binding component
- b)
- Found in muscle fibers and help regulate
- contraction
- c)
- TnI and TnT released from dying muscle during
- necrosis
- i)
- TnI more specific to heart
- d)
- Not released in angina b/c no muscle death
- e)
- Measured within 6hrs of AMI
- f)
- Remain elevated for 14days
- g)
- Preferred marker for AMI
-
Enzyme
- a)
- Biological protein that catalyzes biochemical
- rxns without being consumed or changed
- b)
- When higher than normal levels are found in the
- peripheral circulation, indicates cellular damage or injury due to disease or
- abnormalities
-
3 historic enz
- b)
- Aspartate amino transferase (AST)
- c)
- Lactate dehydrogenase (LD)
-
typical analysis of cardiac enzymes
- Cardiac enz are usually analyzed together several times per day over
- period of time (1week) to observe peak and return to normal
-
Iso-enzyme
- a)
- Different form of enzyme
- b)
- Maintain same catalytic function
- c)
- Diff found in sub-unit strux
- d)
- Measured based on physiological properties
- e)
- Sum of iso-enzyme concentrations is equal to the
- total parent enzyme concentration
-
Creatine kinases
- i)
- Mostly skeletal muscle
- ii)
- Large increase when skeletal muscle trauma or
- disease like dystrophy
- i)
- Brain and nerve, and embryonic form in serum of
- newborns
- ii)
- Also found in embryonic malignancies
- i)
- Mostly in cardiac muscle
- ii)
- Released by necrotic heart muscle
- iv) Rises
- faster and returns to normal faster than total CK
-
CK-MB
- b)
- Decrease by degradation mech until no longer
- detected
- d)
- Use % CK-MB b/c total CK can be influenced by
- other isoenzymes
- e)
- MB index using total CK and CK-MB
-
LD
- i)
- LD1 – heart muscle, RBCs, kidney
- ii)
- LD2 _ Heart, RBCs, kidney
- iii) LD3
- – lung, lymph, sleen, pancreas
- iv) LD4
- – Liver, skeletal muscle
- v)
- LD5 - Liver, skeletal muscle
- c)
- AMI LD1 > LD2 (typical of heart muscle
- damage, but not specific)
- d)
- Rises slow but remains for 4-7 days
- e)
- Hemolysis can increase concentrations
-
Markers of cardiac risk
- a)
- High sensitivity C-reactive protein (HS-CRP)
- a)
- Ischemia-modified albumin (IMA)
-
High sensitivity C-reactive protein (HS-CRP)
- i)
- Acute phase that increases rapidly in response
- to inflammation, infection, or tissue damage
- ii)
- High sensitivity allows for detection of small
- increases seen in cardiac disease
- iii) Increase
- in baseline HS-CRP = higher risk for coronary artery disease
-
Lipoprotein (a)
- i)
- Variant of LDL with extra apoprotein called
- apoprotein (a)
- ii)
- Homology btwn apoprotein (a) and plasminogen
- causes competition btwn the two for binding sites
- iii) If
- Increase in concentration of lipoprotein (a) will promote clot formation
- because more plsminogen will be unbound
- iv) Increase
- levels of Lp (a) = increased risk for coronary artery disease
-
Ischemia-modified albumin (IMA)
- i)
- Albumin undergoes conformational change when it
- contacts ischemic muscle
- ii)
- Increases in IMA = increased probability of AMI
- iii) Very
- early marker, drops rapidly after peaking in less than 8 hrs
- iv) Use
- in conjunction with troponin
-
Myoglobin
- a)
- Released from striated muscle when damaged
- b)
- Rises fast 2hrs. peaks 6-8 hrs. normal 18-24 hrs
- d)
- Not conclusive by itself. Must confirm with
- increased troponin
- e)
- Timing of test important
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