Cardiac Markers Flashcards
Ideal _______________ involves intact muscle cells, and adequate blood and oxygen supply.
Homeostasis
True or false: ischaemia is reversible.
True
Infarction is ______ ________, after prolonged ischaemia.
Cell death
__________ is the result of blockage of the blood vessels supplying oxygen to the myocardial cells.
Ischaemia
CAD’s major cause is atherosclerosis, which causes _______ formation within large- and medium-sized arteries.
Plaque
Plaque is a pearly white area within an artery, which internally is made of lipid, cell debris, smooth muscle cells, collagen, and calcium, covered with a __________ ____.
Fibrous cap
Arterial blood flow is reduced across plaque, leading to narrow ________.
Lumen
________ ______________ ____________ is associated with heart pain, and death of heart tissue.
Acute myocardial infarction
______ ___________ of the myocardium, may result during AMI, as a result of interruption to the blood supply.
Gross necrosis
List the three principal characteristics of AMI.
Crushing chest pain
ECG changes
Cardiac muscle enzyme/markers will be released
What elements are used to diagnose AMI?
History, clinical and presentation, changes to ECG (although differences may not be immediately noticeable), and evaluation of cardiac markers
__________ are regulatory proteins, found in contractile proteins of myofibrils.
Troponins
Where is troponin C found?
Heart and skeletal muscle
Why is troponin C not useful as a cardiac marker?
The heart isoform is identical to slow twitch muscle
Why is troponin I useful as a cardiac marker?
Unique cardiac specificity, as it has only one isoform
___________ __ has eleven unique amino acids, lending specific markedness to the protein.
Troponin T
When is troponin T released into circulation?
After injury to the heart
How many main isoforms of troponin T are known?
Two
______________ is an oxygen-binding protein of cardiac and skeletal muscle.
Myoglobin
True or false: myoglobin is found in the cytoplasm, and increases rapidly after a cardiac event.
True
___________ ________ catalyses the formation phosphocreatine from creatine and ATP.
Creatinine kinase
The ________ form of creatinine kinase is a dimer made of two subunits, M (muscle) and B (brain).
Cytosolic
CKBB, CKMB, and CKMM forms of creatinine kinase exist, with the ____________ CK1, CK2, and CK3, respectively.
Isoenzymes
_______________ creatinine kinase has two isoenzymes.
Mitochondrial
_________ is prominent in both skeletal and cardiac muscle.
CKMM
___________ ______________ is an isoenzyme that catalyses the reduction of pyruvate to (L)-lactate, using NADH as an electron donor.
Lactate dehydrogenase
Highest activity of lactate dehydrogenase is observed in __________ ________, liver, heart, kidney, and RBC.
Skeletal muscle
List the five isoenzymes of lactate dehydrogenase.
LD1 (H4) (heart, kidney, and RBC)
LD2 (H3M)
LD3 (H2M2)
LD4 (HM3)
LD5 (M4) (skeletal muscle and liver)
Most methods of measuring troponin I employ __________ ___________.
Monoclonal antibodies
Assay times for troponin I vary from ______ to thirty minutes.
Seven
Quantitative assays for ___________ ___ include immunoassays for serum/plasma, with antibodies and reagents; there is no cross-reactivity with skeletal muscle isoforms.
Troponin T
Use of monoclonal antibody tests for ___________ can be an early marker.
Myoglobin
List two methods of measuring creatinine kinase.
Electrophoresis and immunoassays
List three qualities of an ideal marker.
Facilitates early AMI diagnosis
Assists in risk stratification
Monitors treatment
CK and CKMB elevate _________ after an event.
Swiftly
__________ is both released and cleared quickly, and is not used in diagnosis, as it has <80% clinical specificity.
Myoglobin
Troponins T and I stay elevated, and have cardiac ____________.
Specificity
Why are troponins not useful in relapse detection?
Values stay elevated for days after the event
List the criteria for AMI.
Evidence of ischaemia
A rise, or a fall, of troponin
At least one troponin reading that is greater than, or equal to, the 99th percentile
True or false: stable angina is irreversible.
False
__________ angina arises when the fibrous cap ruptures.
Unstable
True or false: high cholesterol, hypertension, and a sedentary lifestyle increase the odds of a cardiac event.
True
____________ levels of homocysteine indicate risk to future events.
Increased
_____ indicates presence of inflammation, but also increased in people at risk for future cardiovascular events.
CRP
What are natriuretic peptides?
Series of ring-shaped molecules that promote an increased loss of sodium and water
___-________ natriuretic peptides are produced by both the atria and the ventricles .
B-type