Nuclear medicine for cardiology Flashcards
List the basic cardiology nuclear exams
Myocardial perfusion studies
Myocardial viability assessment
Central circulation exam
Further exams
Metabolic tests: glucose, lipid, amino acid, oxidative metabolism
Receptor examinations: adrenergic, cholinergic, etc.
Apoptosis, molecular level imaging.
Myocardial perfusion studies
the radiotracer is injected at the peak of the stress exam and its result is compared to the resting state.
Tracers used:
sestaMIBI. Tetrofosmin. - both Tc coupled, accumulate in functioning mitochondria. Incorporated rapidly without redistribution.
201 Thallium - Reflects tissue perfusion for 30 minutes before redistribution. Increased/late retention and delayed washout indicates ischemic lesions. No uptake or accumulation at all indicates necrosis.
PET emitters:
O15 whater, N13 ammonium - these are more expensive than SPECT tracers and about equally effective, so they aren’t used clinically.
ECG gated SPECT and PET, times the acquisition with the R-R interval to visualize a contraction capturing at specific time windows. To visualize wall motion, EF and funcitonal values of the heart.
Drugs used for stress: Adenosine, Dipyridamole, Dobutamine
Myocardial viability assessment
Perfusion tracers only accumulate in living myocytes,
so PET/SPECT can identify living but nonfunctioning myocardium,
ie Hibernating myocardium that may be rescued by revascularization.
First Pass examination Radionuclide Angiography
FP-RNA
planar imaging, ie 2d flat image
A bolus Tc tracer is injected and imaged as it travels through its first pass of the circulation.
Can estimate Right and left ventricle function, stroke volumes, and transit times of blood flow.
Myocardial metabolic tests used in clinics
18FDG, PET scan for glucose uptake
123I labeled fatty acids to determine FA uptake
Receptor imaging in clinical practice
123I MIBG - to asses alpha receptor density with SPECT.
