Cardiac biomarkers Flashcards
What is the difference between myocardial infarction and ischemia
Infarction - heart attack
Ischemia - low blood/O2 supply to heart
What is the most common cause of ACS
Atherosclerosis
What is angina
Chest pain as a result of balance of O2 demand and supply
What is NSTEMI
Subendocardial infarct
What is STEMI
Transmural infarct
What would you see in an ECG for a patient with ACS
ST elevation - above PR interval
What is a biomarker
A substance used as an indicator of biologic state
What is a cardiac marker
Substances released from the heart muscle when stressed or damaged
What does creatinine kinase do
Catalyses conversion on creatinine in creatinine phosphate
What happen to CK in MI
Increases
Where is CK-MB found
Heart
Where is CK-BB found
Brain
Where is CK-MM found
Skeletal muscle
Which iso-enzyme of CK has a high specificity for cardiac tissue
CK-MB
What are the limitations of measuring CK
Less specific to troponin
Present in skeletal and heart muscle
Trauma/ surgery can trigger plasma levels
Less relevant when patient presents late
What are some non MI causes of CK elevation
Skeletal muscle injury
CNS damage
Hypothyroidism
Where is cardiac troponin found
Muscle fibres
What does cardiac troponin do
Regulate contractions
Released into blood following injury to heart
Which isoforms of troponin are released during infarction
I and T
What is myoglobin and where is it found
Oxygen binding protein
Found in cytoplasm of striated muscle cells
What does LDH do
Converts pyruvate to lactase
