CVT CVT Cardiac Imaging & Nuclear Cardiology 1 — Questions and Answers
Question 1: In nuclear cardiology, which radiopharmaceutical is most commonly used for myocardial perfusion imaging (MPI)?
- Thallium-201
- Technetium-99m sestamibi (MIBI) (Correct answer)
- Fluorine-18 FDG
- Indium-111
Correct answer: Technetium-99m sestamibi (MIBI)
Tc-99m sestamibi is the most widely used agent for SPECT MPI because of its favorable dosimetry, higher photon energy, and ability to assess both perfusion and function.
Question 2: A 'fixed defect' on nuclear myocardial perfusion imaging indicates:
- Ischemia that resolves with rest
- Infarction with non-viable myocardium (scar tissue) (Correct answer)
- Normal perfusion in all phases
- Artifact from patient motion
Correct answer: Infarction with non-viable myocardium (scar tissue)
A fixed (unchanging) perfusion defect present on both stress and rest images indicates infarcted, non-viable myocardial tissue.
Question 3: Which cardiac imaging modality provides the highest spatial resolution for coronary artery anatomy?
- Transthoracic echocardiography
- Nuclear SPECT imaging
- Cardiac CT angiography (CCTA) (Correct answer)
- Holter monitoring
Correct answer: Cardiac CT angiography (CCTA)
Cardiac CT angiography provides sub-millimeter spatial resolution for direct visualization of coronary artery anatomy, stenoses, and atherosclerotic plaque.
Question 4: The Agatston score obtained from cardiac CT quantifies:
- Left ventricular ejection fraction
- Coronary artery calcium burden as a marker of atherosclerosis (Correct answer)
- Aortic valve area
- Pericardial effusion volume
Correct answer: Coronary artery calcium burden as a marker of atherosclerosis
The Agatston (coronary artery calcium) score measures calcified atherosclerotic plaque burden in the coronary arteries, stratifying cardiovascular risk.
Question 5: What does LVEF stand for and what is the normal range in adults?
- Left Ventricular Ejection Fraction; normal ≥55% (Correct answer)
- Left Ventricular End-diastolic Function; normal ≥45%
- Left Ventricular Ejection Fraction; normal ≥35%
- Left Ventricular Effort Factor; normal ≥65%
Correct answer: Left Ventricular Ejection Fraction; normal ≥55%
LVEF (Left Ventricular Ejection Fraction) is the percentage of blood ejected with each beat; a normal LVEF is ≥55%, indicating preserved systolic function.
Question 6: In cardiac MRI, late gadolinium enhancement (LGE) is used to detect:
- Coronary artery stenosis
- Myocardial fibrosis and infarct scar (Correct answer)
- Pericardial effusion
- Valvular regurgitation severity
Correct answer: Myocardial fibrosis and infarct scar
LGE CMR identifies myocardial fibrosis and scar because gadolinium contrast accumulates in areas of damaged myocardium with expanded extracellular space.
CVT CVT Cardiac Imaging & Nuclear Cardiology 1
In nuclear cardiology, which radiopharmaceutical is most commonly used for myocardial perfusion imaging (MPI)?