EACVI Cardiac Computed Tomography Practice Exam
Questions with Correct Answers
Question 1: A 62-year-old male with a history of hypertension and dyslipidemia presents to the
outpatient clinic with typical angina. His baseline ECG is normal, and resting heart rate is 72 bpm. He is
scheduled for a Coronary Computed Tomography Angiography (CCTA). Prior to image acquisition, oral
metoprolol is administered to achieve optimal heart rate control. Which of the following heart rate
targets and temporal phases is most ideal for minimizing motion artifact of the coronary arteries,
particularly the right coronary artery (RCA), on a single-source 64-slice MDCT scanner?
A. Heart rate < 65 bpm, acquisition targeted at end-systolic phase (30-40% of R-R interval)
B. Heart rate < 60 bpm, acquisition targeted at mid-diastolic phase (65-75% of R-R interval)
C. Heart rate < 75 bpm, acquisition targeted at early-systolic phase (10-20% of R-R interval)
D. Heart rate < 80 bpm, acquisition targeted at late-diastolic phase (85-95% of R-R interval)
CORRECT ANSWER: B. Heart rate < 60 bpm, acquisition targeted at mid-diastolic phase (65-75% of R-R
interval)
Rationale:
Optimal temporal resolution in single-source CCTA relies heavily on heart rate control. At lower heart
rates (< 60 bpm), the mid-diastolic period (diastasis) is significantly lengthened, providing a stable
window with minimal cardiac motion (typically at 65-75% of the R-R interval). The right coronary artery
(RCA) experiences the highest motion velocity during the cardiac cycle and benefits most from mid-
diastolic imaging at lower heart rates. End-systolic acquisition (30-40%) is generally reserved for patients
with higher heart rates or atrial fibrillation when diastasis is shortened or variable.
Question 2: A 55-year-old female undergoes CCTA for stable chest pain. During contrast injection, dual-
source CT acquisition is performed using a bolus tracking technique. The region of interest (ROI) is
placed in the ascending aorta. Which of the following attenuation thresholds (in Hounsfield Units, HU)
is standardly used to trigger the scan sequence after reaching peak aortic opacification?
A. 50 HU
B. 100 to 150 HU
C. 300 to 350 HU
D. 500 HU
CORRECT ANSWER: B. 100 to 150 HU
,Rationale:
In bolus tracking for CCTA, a real-time low-dose monitoring sequence measures dynamic attenuation
inside a ROI positioned within the ascending aorta (or main pulmonary artery in specific protocols). A
trigger threshold of 100 to 150 Hounsfield Units (HU) above baseline is standardly programmed. Once
this threshold is breached, a diagnostic scan delay (diagnostic delay time, typically 3–6 seconds) allows
peak arterial contrast opacification (typically reaching 300-400 HU in the coronary lumen) before high-
resolution imaging begins.
Question 3: A 70-year-old male with chronic kidney disease (eGFR 42 mL/min/1.73m²) is evaluated for
severe aortic stenosis prior to Transcatheter Aortic Valve Implantation (TAVI/TAVR). A dedicated TAVI
CT protocol is planned. To minimize contrast-induced nephropathy while maintaining sufficient
vascular attenuation, which scan optimization technique is most appropriate?
A. Increase tube voltage (kVp) to 140 kVp and increase contrast volume
B. Lower tube voltage (kVp) to 80-100 kVp and utilize high-concentration contrast at reduced volume
C. Perform non-contrast CT only and forego luminal measurement
D. Use a fixed prospective ECG gating at 120 kVp with delayed acquisition by 45 seconds
CORRECT ANSWER: B. Lower tube voltage (kVp) to 80-100 kVp and utilize high-concentration contrast
at reduced volume
Rationale:
Lowering the tube voltage (e.g., from 120 kVp to 80 or 100 kVp) shifts the X-ray energy spectrum closer
to the K-edge of iodine (33.2 keV). This markedly increases photoelectric absorption and diagnostic
attenuation of iodinated contrast media. Consequently, equivalent or superior intravascular signal (HU)
can be obtained using significantly smaller volumes of iodinated contrast material, which is vital for
protecting renal function in patients with chronic kidney disease undergoing pre-TAVI workup.
Question 4: A 48-year-old symptomatic patient undergoes CCTA. Visual assessment reveals a non-
calcified plaque in the proximal left anterior descending (LAD) artery causing luminal narrowing. The
inner luminal diameter at the point of maximal stenosis is measured at 1.8 mm compared to a
proximal reference diameter of 3.6 mm. According to the SCCT CAD-RADS 2.0 classification, how
should this stenosis severity be categorized?
A. CAD-RADS 1 (Minimal: 1-24%)
B. CAD-RADS 2 (Mild: 25-49%)
C. CAD-RADS 3 (Moderate: 50-69%)
D. CAD-RADS 4A (Severe: 70-99%)
,CORRECT ANSWER: C. CAD-RADS 3 (Moderate: 50-69%)
Rationale:
Stenosis diameter percentage is calculated as: $100 \times [1 - (\text{Stenotic Diameter} /
\text{Reference Diameter})] = 100 \times [1 - (1..6)] = 50\%$. According to CAD-RADS 2.0 reporting
guidelines:
• CAD-RADS 0: 0% (Documented absence of CAD)
• CAD-RADS 1: 1–29% (Minimal)
• CAD-RADS 2: 30–49% (Mild)
• CAD-RADS 3: 50–69% (Moderate)
• CAD-RADS 4A: 70–99% single/double vessel severe stenosis
• CAD-RADS 4B: Left Main >50% or 3-vessel severe stenosis (70–99%)
• CAD-RADS 5: 100% (Total occlusion)
Therefore, a 50% diameter reduction is classified as CAD-RADS 3.
Question 5: During a non-contrast Non-ECG or ECG-gated Agatston Coronary Artery Calcium (CAC)
scoring scan, a lesion in the left circumflex artery displays an area of 12 mm² with a peak attenuation
of 320 Hounsfield Units (HU). What density factor multiplier is applied to this area to calculate the
Agatston score contribution for this lesion?
A. 1
B. 2
C. 3
D. 4
CORRECT ANSWER: C. 3
Rationale:
The Agatston score is calculated by multiplying the area of a calcified plaque (threshold defined as $\ge
130\text{ HU}$ and area $\ge 1\text{ mm}^2$) by a density factor derived from the peak CT attenuation
(HU) within that specific plaque:
• 130–199 HU: Factor 1
• 200–299 HU: Factor 2
• 300–399 HU: Factor 3
, • $\ge 400\text{ HU}$: Factor 4
Since the peak attenuation of 320 HU falls in the range of 300–399 HU, the multiplier factor is 3. The
Agatston score contribution for this lesion is $12\text{ mm}^2 \times 3 = 36$.
Question 6: A 38-year-old male athlete presents with exertional syncope. CCTA is performed to rule out
congenital coronary artery anomalies. The scan demonstrates an anomalous origin of the right
coronary artery (RCA) originating from the left sinus of Valsalva. Which high-risk anatomical trajectory
feature is most strongly associated with sudden cardiac death in this patient population?
A. Retroaortic course
B. Interarterial course (between the aorta and pulmonary artery) with intramural path
C. Prepulmonic course
D. Retrocardiac subendocardial course
CORRECT ANSWER: B. Interarterial course (between the aorta and pulmonary artery) with intramural
path
Rationale:
Anomalous origin of a coronary artery from the opposite sinus of Valsalva (ACAOS) with an interarterial
course—specifically when accompanied by an intramural segment (where the anomalous vessel travels
within the aortic tunic media), slit-like ostium, and acute take-off angle—carries the highest risk of
exertional dynamic compression, ischemia, malignant ventricular arrhythmias, and sudden cardiac death
during exercise. Prepulmonic, retroaortic, and retrocardiac courses are considered benign anomalies.
Question 7: A 67-year-old male undergoes CCTA for suspected coronary artery disease. Analysis of
high-risk plaque (HRP) features is performed. Which combination of plaque characteristics on CCTA is
most indicative of a vulnerable plaque associated with acute coronary syndrome (ACS)?
A. High attenuation (> 400 HU), dense circumferential calcification, and absence of remodeling
B. Low attenuation plaque (< 30 HU), positive remodeling, spotty calcification, and the napkin-ring sign
C. Homogeneous intermediate attenuation (100 HU) without expansion of the vessel wall
D. Diffuse calcification with lumen diameter contraction (negative remodeling)
CORRECT ANSWER: B. Low attenuation plaque (< 30 HU), positive remodeling, spotty calcification, and
the napkin-ring sign
Rationale:
High-Risk Plaque (HRP) features on CCTA strongly correlate with thin-cap fibroatheromas (TCFA) and
future acute cardiac events. The four classic high-risk features identified on CCTA are:
Questions with Correct Answers
Question 1: A 62-year-old male with a history of hypertension and dyslipidemia presents to the
outpatient clinic with typical angina. His baseline ECG is normal, and resting heart rate is 72 bpm. He is
scheduled for a Coronary Computed Tomography Angiography (CCTA). Prior to image acquisition, oral
metoprolol is administered to achieve optimal heart rate control. Which of the following heart rate
targets and temporal phases is most ideal for minimizing motion artifact of the coronary arteries,
particularly the right coronary artery (RCA), on a single-source 64-slice MDCT scanner?
A. Heart rate < 65 bpm, acquisition targeted at end-systolic phase (30-40% of R-R interval)
B. Heart rate < 60 bpm, acquisition targeted at mid-diastolic phase (65-75% of R-R interval)
C. Heart rate < 75 bpm, acquisition targeted at early-systolic phase (10-20% of R-R interval)
D. Heart rate < 80 bpm, acquisition targeted at late-diastolic phase (85-95% of R-R interval)
CORRECT ANSWER: B. Heart rate < 60 bpm, acquisition targeted at mid-diastolic phase (65-75% of R-R
interval)
Rationale:
Optimal temporal resolution in single-source CCTA relies heavily on heart rate control. At lower heart
rates (< 60 bpm), the mid-diastolic period (diastasis) is significantly lengthened, providing a stable
window with minimal cardiac motion (typically at 65-75% of the R-R interval). The right coronary artery
(RCA) experiences the highest motion velocity during the cardiac cycle and benefits most from mid-
diastolic imaging at lower heart rates. End-systolic acquisition (30-40%) is generally reserved for patients
with higher heart rates or atrial fibrillation when diastasis is shortened or variable.
Question 2: A 55-year-old female undergoes CCTA for stable chest pain. During contrast injection, dual-
source CT acquisition is performed using a bolus tracking technique. The region of interest (ROI) is
placed in the ascending aorta. Which of the following attenuation thresholds (in Hounsfield Units, HU)
is standardly used to trigger the scan sequence after reaching peak aortic opacification?
A. 50 HU
B. 100 to 150 HU
C. 300 to 350 HU
D. 500 HU
CORRECT ANSWER: B. 100 to 150 HU
,Rationale:
In bolus tracking for CCTA, a real-time low-dose monitoring sequence measures dynamic attenuation
inside a ROI positioned within the ascending aorta (or main pulmonary artery in specific protocols). A
trigger threshold of 100 to 150 Hounsfield Units (HU) above baseline is standardly programmed. Once
this threshold is breached, a diagnostic scan delay (diagnostic delay time, typically 3–6 seconds) allows
peak arterial contrast opacification (typically reaching 300-400 HU in the coronary lumen) before high-
resolution imaging begins.
Question 3: A 70-year-old male with chronic kidney disease (eGFR 42 mL/min/1.73m²) is evaluated for
severe aortic stenosis prior to Transcatheter Aortic Valve Implantation (TAVI/TAVR). A dedicated TAVI
CT protocol is planned. To minimize contrast-induced nephropathy while maintaining sufficient
vascular attenuation, which scan optimization technique is most appropriate?
A. Increase tube voltage (kVp) to 140 kVp and increase contrast volume
B. Lower tube voltage (kVp) to 80-100 kVp and utilize high-concentration contrast at reduced volume
C. Perform non-contrast CT only and forego luminal measurement
D. Use a fixed prospective ECG gating at 120 kVp with delayed acquisition by 45 seconds
CORRECT ANSWER: B. Lower tube voltage (kVp) to 80-100 kVp and utilize high-concentration contrast
at reduced volume
Rationale:
Lowering the tube voltage (e.g., from 120 kVp to 80 or 100 kVp) shifts the X-ray energy spectrum closer
to the K-edge of iodine (33.2 keV). This markedly increases photoelectric absorption and diagnostic
attenuation of iodinated contrast media. Consequently, equivalent or superior intravascular signal (HU)
can be obtained using significantly smaller volumes of iodinated contrast material, which is vital for
protecting renal function in patients with chronic kidney disease undergoing pre-TAVI workup.
Question 4: A 48-year-old symptomatic patient undergoes CCTA. Visual assessment reveals a non-
calcified plaque in the proximal left anterior descending (LAD) artery causing luminal narrowing. The
inner luminal diameter at the point of maximal stenosis is measured at 1.8 mm compared to a
proximal reference diameter of 3.6 mm. According to the SCCT CAD-RADS 2.0 classification, how
should this stenosis severity be categorized?
A. CAD-RADS 1 (Minimal: 1-24%)
B. CAD-RADS 2 (Mild: 25-49%)
C. CAD-RADS 3 (Moderate: 50-69%)
D. CAD-RADS 4A (Severe: 70-99%)
,CORRECT ANSWER: C. CAD-RADS 3 (Moderate: 50-69%)
Rationale:
Stenosis diameter percentage is calculated as: $100 \times [1 - (\text{Stenotic Diameter} /
\text{Reference Diameter})] = 100 \times [1 - (1..6)] = 50\%$. According to CAD-RADS 2.0 reporting
guidelines:
• CAD-RADS 0: 0% (Documented absence of CAD)
• CAD-RADS 1: 1–29% (Minimal)
• CAD-RADS 2: 30–49% (Mild)
• CAD-RADS 3: 50–69% (Moderate)
• CAD-RADS 4A: 70–99% single/double vessel severe stenosis
• CAD-RADS 4B: Left Main >50% or 3-vessel severe stenosis (70–99%)
• CAD-RADS 5: 100% (Total occlusion)
Therefore, a 50% diameter reduction is classified as CAD-RADS 3.
Question 5: During a non-contrast Non-ECG or ECG-gated Agatston Coronary Artery Calcium (CAC)
scoring scan, a lesion in the left circumflex artery displays an area of 12 mm² with a peak attenuation
of 320 Hounsfield Units (HU). What density factor multiplier is applied to this area to calculate the
Agatston score contribution for this lesion?
A. 1
B. 2
C. 3
D. 4
CORRECT ANSWER: C. 3
Rationale:
The Agatston score is calculated by multiplying the area of a calcified plaque (threshold defined as $\ge
130\text{ HU}$ and area $\ge 1\text{ mm}^2$) by a density factor derived from the peak CT attenuation
(HU) within that specific plaque:
• 130–199 HU: Factor 1
• 200–299 HU: Factor 2
• 300–399 HU: Factor 3
, • $\ge 400\text{ HU}$: Factor 4
Since the peak attenuation of 320 HU falls in the range of 300–399 HU, the multiplier factor is 3. The
Agatston score contribution for this lesion is $12\text{ mm}^2 \times 3 = 36$.
Question 6: A 38-year-old male athlete presents with exertional syncope. CCTA is performed to rule out
congenital coronary artery anomalies. The scan demonstrates an anomalous origin of the right
coronary artery (RCA) originating from the left sinus of Valsalva. Which high-risk anatomical trajectory
feature is most strongly associated with sudden cardiac death in this patient population?
A. Retroaortic course
B. Interarterial course (between the aorta and pulmonary artery) with intramural path
C. Prepulmonic course
D. Retrocardiac subendocardial course
CORRECT ANSWER: B. Interarterial course (between the aorta and pulmonary artery) with intramural
path
Rationale:
Anomalous origin of a coronary artery from the opposite sinus of Valsalva (ACAOS) with an interarterial
course—specifically when accompanied by an intramural segment (where the anomalous vessel travels
within the aortic tunic media), slit-like ostium, and acute take-off angle—carries the highest risk of
exertional dynamic compression, ischemia, malignant ventricular arrhythmias, and sudden cardiac death
during exercise. Prepulmonic, retroaortic, and retrocardiac courses are considered benign anomalies.
Question 7: A 67-year-old male undergoes CCTA for suspected coronary artery disease. Analysis of
high-risk plaque (HRP) features is performed. Which combination of plaque characteristics on CCTA is
most indicative of a vulnerable plaque associated with acute coronary syndrome (ACS)?
A. High attenuation (> 400 HU), dense circumferential calcification, and absence of remodeling
B. Low attenuation plaque (< 30 HU), positive remodeling, spotty calcification, and the napkin-ring sign
C. Homogeneous intermediate attenuation (100 HU) without expansion of the vessel wall
D. Diffuse calcification with lumen diameter contraction (negative remodeling)
CORRECT ANSWER: B. Low attenuation plaque (< 30 HU), positive remodeling, spotty calcification, and
the napkin-ring sign
Rationale:
High-Risk Plaque (HRP) features on CCTA strongly correlate with thin-cap fibroatheromas (TCFA) and
future acute cardiac events. The four classic high-risk features identified on CCTA are:
