Cardiac Markers Flashcards
What are the four types of Cardiovascular disease
Coronary heart disease
-manifests as MI and heart failure
Cerebrovascular disease
-mini and major stroke
Peripheral arterial disease
-blockage of the arteries of the extremities (legs)
Aortic atherosclerotic disease
-aneurysms or dissections
all caused by presence of atherosclerosis
Arterioschlerosis
Harding of the arteries (especially the coronary arteries), results from the deposition of tough, rigid collagen inside the vessel wall and around the atheroma, which is described as fatty degeneration or thickening of the walls of the larger arteries (left and right coronary arteries, left anterior descending artery, and circumflex artery).
Atherosclerosis
Refers to the most common form of arteriosclerosis affecting the arterial blood vessels and is caused by the formation of multiple plaques within coronary arteries. Coronary arteries supply the cardiac tissue with blood containing oxygen and other nutrients.
Ischemia
If the coronary vessels are occluded and the blood supply is reduced, then myocardial tissue supplied by the vessels begins to lose function. This process is called cardiac ischemia. If cardiac ischemia is allowed to continue, cells will begin to die; this cell death is called necrosis.
Results in the typical symptoms of MI: a feeling of a squeezing of the chest, heavy chest pain, burning feeling, nausea, dizziness, and shortness of breath
What markers were first used to detect cardiac damage, and what are used now?
First=GOT/AST
Now=LDH and CK-MB, troponin
Troponin protein complex
3 proteins: cTnT, cTnI, cTnC
What do cTnI and cTnT do?
They are expressed in fast twitch, slow twitch and cardiac muscle
What type of troponin is increased with a myocardial infarction?
cTnI, over 100ng/mL
Also cTnT
Troponin C
Not specific to cardiac sources so not commonly used as cardiac marker
Troponin T
Elevated in MI. Also elevated in chronic renal failure, skeletal muscle injury, muscular dystrophy, and myositis. Less specific in immunoassays
Troponin I
Elevated in myocardial infarction. More specific. Only found in serum in cases of necrosis. Normally very low in serum.
What do you use to monitor heart failure
B-type natriuretic peptide (BNP) or NT-proBNP, or troponins.
B-type natriuretic peptide
Is helpful to distinguish cardia from non-cardiac causes of dyspnea. Natriuretic peptides are secreted from the heart in response to increased pressure and volume load.
C reactive protein
Acute marker of inflammation that is currently used clinically in the evaluation of CVD risk
Homocystenine
Sulfur-containing amino acid formed in plasma from the metabolic demethylation of methionine. Link between high levels of plasma homocysteine and CVD
