Cardiac Imaging/Labs Flashcards
Pulsus paradoxus
- Drop in systolic pressure by 10+ mm Hg during inspiration
- D/t increased pressure in thoracic compartment
Pulsus alterans
Pulse alternates in amplitude from beat to beat when rhythm is normal
What might pulsus alterans suggest?
LV failure
2 types of murmurs:
- Stenotic
2. Insufficient (regurgitation)
Approach to the cardiac patient by NYHA guidelines:
- Underlying etiology
- Anatomic abnormality present (or not)
- Physiologic disturbance or not
- Functional disability or not
BNP - what is it, where is it produced?
- Brain natriuretic peptide
- Made in the ventricles
- Marker for ventricular dysfunction
When do BNP levels increase?
-In response to increased ventricular volume and pressure overload (decreased EF)
What is BNP useful in diagnosing/assessing?
Severity of CHF
*400+ pg/dL is high predictor for CHF
What are the 3 CK isoenzymes?
- CK-BB (brain/lung)
- CK-MB (myocardial cells)
- CK-MM (skeletal muscle)
Tell me about CK-MB levels
- Levels rise 3-6 hours after infarction
- Peak 12-24 hrs and return to normal 12-48 hrs after infarction IF no further damage
What does CK-MB tell us about an infarct?
- Quantifies the severity of an MI
- Determines the onset of an MI
Myoglobin is more ___ than CK isoenzymes but not as ____
More sensitive
Not as specific
Tell me about myoglobin levels
- Rise in 2-3 hours after muscle injury/death
- Peaks at 6-9 hours
What is LDH?
- Lactate dehydrogenase
- Increased levels indicate cellular death and leakage of the enzyme from the cell
What do elevated levels of LDH indicate?
- Nonspecific
- Increase 36-55 hrs after MI (but can increase d/t a number of things)
What are troponins?
- Proteins present in skeletal and cardiac muscle
- Regulate Ca interaction for contraction
- Types = TC, TI, TT
What are cardiac troponins?
T and I
When do Troponin I and T levels increase/return to normal?
- 1-3 hours after injury
- Returns to normal within 5-7 days
Troponin I remains increased longer than ___ and is more cardiac specific
CK-MB
Troponin T is more ___ than CK-MB but less ___
More sensitive
Less specific
What is the preferred test to diagnose an MI?
Troponins
Why do we care about AST levels?
- Increased with an MI
- Not specific though
What does a lipid panel include?
Total cholesterol
LDL
HDL
Triglycerides
Types of echo
Transthoracic (TTE)
Transesophageal (TEE)
What is the gold standard for evaluating valve morphology and motion?
TTE
What is the gold standard for detecting pericardial effusions and tamponade?
TTE
What is the advantage of TEE?
Gives more detailed pic of heart (especially posterior structures - LA, mitral valve, aorta)
What is the difference between Holter and Event monitoring?
Holter = 24-48 hour recording
Event = up to 30 days recording
Both are continuous EKG
What is the basic principle behind exercise stress testing?
- Occluded arteries will be unable to meet heart’s increased demand
- Pt will become symptomatic or develop EKG changes
What is the gold standard in assessing anatomy and physiology of the heart?
Cardiac cath and coronary angiography
What is the MC risk with cardiac cath and coronary angiography?
Access site bleeding
