2A: Cardiac Pathologies II Flashcards
What is the goal for treating CAD?
Halt progression and possible improvement with risk factor modification
What is the definition of an MI?
Ischemic event that may result in injury or irreversible tissue death at the myocardium
What are the three signs and symptoms of an MI?
- ECG changes
- Cardiac symptoms
- Elevation of cardiac enzymes
What are possible ECG changes with an MI?
- S-T segment elevation
- Inverted T wave
- Significant Q wave
How is an MI ruled in or out?
Must have 2/3 key symptoms
What are the three zones of infarct of MI?
- Zone of ischemia
- Zone of injury
- Zone of infarct
What is the zone of ischemia?
Tissue is viable and may not have any damage if infarct doesn’t extend
What is the zone of injury?
Viable as long as O2 delivery stays intact. Increasing O2 delivery can save the tissue
What is the zone of infarct?
Tissue is O2 deprived and has irreversible damage
What zones can intervention have an effect on?
Zone of ischemia and injury
What are the three main cardiac enzymes of interest with an MI?
- CPK-MB
- Troponin
- LDH-1
When will CPK-MB increase?
0-24 hrs after MI
Why is CPK-MB a marker for MI?
Because MB is an isoenzyme that is specific to cardiac tissue
When will troponin increase after an MI?
12 hrs - 4 days after
How does LDH-1 indicate MI?
Look at the ratio of LDH-1 to LDH-2. If it is greater than 1, suggests MI
What are the two main classifications of MI?
Transmural and Subendocardial
What is a transmural MI?
Goes into the wall of the myocardium, will see the most wall motion deficits
What is a hypokinetic transmural MI?
Decreased wall motion
What is a dyskinetic transmural MI?
Unorganized wall motion
What is an akinetic transmural MI?
No wall motion