Nuclear Cardiology Flashcards
What is assessed for in nuclear cardiology?
Function
viability
Perfusion
Ventricular performance/volume/ejection fraction (EF)
How do we get non blurry pictures of the heart since it is always in motion?
Using EKG Gating. EKG is taken with imaging and snapshot images are taken in time to correspond to different cardiac cycles i.e. P, QRS, T, systole/diastole. Some computers can even put these into moving images
What does nuclear medicine of the heart used for?
Evaluate perfusion
What radionuclides can/are used for NM?
Thallium 201
Technicium 99m Sestamibi (retained in myocardial mitochondria)
Technicium 99m Tetrofosmin
What does a stress test measure?
Blood flow to the heart during exercise and at rest
*pt continually monitored
What drugs can be used if pt cannot tolerate stress test to duplicate cardiac stress?
Dobutamine (beta-1 agonist) ianotropic
Lexiscan (adenosine analogs) dilate blood vessels
dipyramidole
The Gamma Camera detects radioactivity via which two methods?
Planar imaging (2D images)
SPECT imaging: multiple 2D images constructed into 3D
*cardiac gated studies can be obtained in both
when interpreting SPECT scans what should you take into consideration?
All factors of patient including;
physical exam
EKG
Echo
NM, etc.
Interpretation study shows perfusion to myocardium is normal during stress and rest
Perfusion is normal (shocker)
Interpretation perfusion is abnormal during stress but normal during rest
limited blood flow (ischemia) most likely
Interpretation perfusion during stress and rest
most likely there is ischemia at all times
Interpretation: What if there is no (I’m guessing he means decreased) perfusion during stress and rest?
Most likely infarction scar
*maybe he means no perfusion to specific area of myocardium
What is the gold standard NM myocardial perfusino study?
Invasive coronary angiography
*catheter fed into aorta and radionuclide enters right and left coronary arteries
What is a PET scan used for in relation to myocardium?
Determine perfusion AND viability of myocardium
*Radionuclide attached to metabolically active molecule (glucose) and will then be taken up via myocardial cells for metabolism or not if dead
*CT scan usually performed simultaneously to aid dx
What is hibernating myocardium?
cardiac tissue that has contractile dysfunction but is still viable and reversible by revascularization
