CARDIAC BIOMARKERS Flashcards
What is atherosclerosis?
build up of fats and cholesterol causing plaques, causing arteries to narrow and restricting blood flow
What is angina?
Chest pain caused by reduce blood flow to the heart
What is stable angina?
Plaques are stable, ischaemia, chest pain in activity
What is unstable angina?
Unstable plaques, chest pain at rest, ischaemia
What is a myocardial infarction?
Heart attack - blood supply to heart is completely blocked
What is a subendocardial infarction?
The inner third of myocardium is affected
What is the difference between angina and a myocardial infarction?
Angina causes reduced blood flow and oxygen supply and an MI causes complete loosing of blood and oxygen
What is a transmural infarction?
Entire blood supply is cut off - endocardium, myocardium and epicardium affected
What conditions need cardiac marker tests?
- triaging chest pain
- suspicious ECG changes
- MI is suspected
What are the cardiac enzyme biomarkers?
- creatine kinase
- ATP
lactate dehydrogenase - gamma glutamyl transferase
What are the non enzyme cardiac markers?
- troponin
- myoglobin
- heart type fatty acid binding
What type of creatine kinase is seen in MI?
CK-MB
What are the limitations of creatine kinase for MI testing?
Present in both skeletal and heart muscle, and positive cases have been recorded
What are the two types of troponin present in heart muscle?
T and I
What does troponin do when heart muscle is damaged?
Leaks into bloodstream
How does troponin in heart muscle differ from that in skeletal muscle?
Troponin T and I have unique amino acid sequences at N terminus which differs from skeletal muscle
What type of troponin is the earliest indicator of an MI?
Troponin I
How is troponin measured?
Radioimmunoassay and enzyme linked immunoabsorbent assay
What is myoglobin and where is it found?
Oxygen binding protein found in heart muscle
“Heart type fatty acid binding protein is an early marker for acute myocardial infarction”
True
What isoenzyme of LDH is found in heart muscle?
LDH 1
