PHARM: Cardiac Biomarkers Flashcards
1
Q
3 main coronary arteries in AMI
A
- R coronary artery
- circumflex artery
- L anterior descending artery
2
Q
STEMI vs NSTEMI
A
- STEMI indicates complete vessel occlusion and full thickness infarct
- NSTEMI indicates partial occlusion and partial infarct
3
Q
criteria to be diagnosed w/ AMI
A
- SIGNIFICANT (99 %ile) increase and/or decrease in a cardiac biomarker, preferably troponin
- AND: ischaemia Sx or an ECG change
4
Q
creatine kinase (CK)
A
- in heart and skeletal muscle
- delivers ATP in short periods of intense demand
- non-specific: don’t differentiate b/n NSTEMI/STEMI/ischaemia
5
Q
cardiac troponin (cTn) - gold standard
A
- regulates cardiac muscle contraction in response to Ca2+
- released by dying muscle > indicates AMI
- detected 4-10 hrs after AMI (peak @ 12-48 hrs)
- can be abnormal for 4-10 days (helps w/ delayed presentation)
6
Q
3 main outcomes after AMI
A
- die instantly (lol)
- heart failure - can be chronic
- cardiac rupture within a week b/c tissue is weak
7
Q
what happens to the cells following AMI?
- within hours
- after a few days
- after that
A
- within hours: lose structure/nuclei, accumulation of blood/fluid
- after a few days: nuclei fragment
- then: coagulative necrosis, cells retain outline (tombstone), further blood/fluid accumulation
8
Q
3 natriuretic peptides
A
- ANP: released by atrial distension, acts to lower BP via vasodilation and Na+ excretion. increased levels indicate heart failure
- BNP (brain): released by ventricular stress, increased levels indicates heart failure
- CNP: endothelium
9
Q
C-reactive protein (CRP)
A
- acute inflammatory biomarker - stimulated by IL-6 from inflammatory cells
- released by dying cells (not cardiac specific)
- binds to surface of dying cells, activates complement system + promotes phagocytosis
10
Q
myoglobin
A
- released by dying skeletal and cardiac muscle
- levels rise within the first few hours of AMI so better than troponin for earlier presentations
