Imaging in CAD

Question 1

Wall motion analysis: what are the cutoffs for normal, hypokinetic, akinetic and dyskinetic wall motion?

Answer 1

Normal: wall thickening >50%
Hypokinetic: wall thickening 10-50%
Akinetic: <10%
Dyskinetic: movement in opposite direction

Question 2

Interpret calcium score = 101-400

Answer 2

Moderate risk - start aspirin and consider statin

Question 3

What FFR indicated significant stenosis?

Answer 3

<0.8

Question 4

CTCA: sensitivity

Answer 4

75-99% sensitive

Question 5

CTCA: PPV

Answer 5

59-91 (low)

Question 6

Interpret calcium score = 0

Answer 6

Very low risk - reassure patient

Question 7

CTCA: NPV

Answer 7

83-99% (high)

Question 8

What is coronary calcium scoring? Which patients is it offered to?

Answer 8

Non-contrast study

Offered to 45-75 year olds with intermediate cardiovascular risk

Question 9

What is FFR?

Answer 9

Fractional flow reserve

Change in pressure across stenotic lesion

Question 10

What is the sensitivity and specificity of STRESS ECHO?

Answer 10

Sensitivity 85%

Specificity 84%

Question 11

What are the sensitivity and specificity of STRESS ECG

Answer 11

Sensitivity 68%

Specificity 77%

Question 12

CTCA: specificity

Answer 12

64-93% specific

Question 13

What are the indications of ischaemia on stress ECG?

Answer 13

ST-segment deviation
Haemodynamics (unable to reach target HR, no BP augmentation with activity)
Symptoms (Chest pain, dyspnoea)
Exercise capacity (METs)
Arrythmias

Question 14

What is the ischaemic cascade?

Answer 14

Ischaemia > diastolic dysfunction > regional systolic dysfunction > ECG changes > chest pain

Question 15

What are the pros and cons of cMRI vs CTCA?

Answer 15

CTCA is better for imaging coronary arteries but cMRI can assess myocardium (normal = black, scar = white with delayed gadolinium enhancement). A transmural scar is unlikely to result in functional benefit after revascularisation.

Question 16

What are the cardiac imaging modalities?

Answer 16

Echocardiogram
cMRI
PET/SPECT
Angiography
Fusion
CTCA

Question 17

Interpret calcium score = 1-100

Answer 17

Low risk - maintenance of healthy diet and lifestyle

Question 18

How does excessive coronary calcification affect CTCA accuracy?

Answer 18

Causes calcium “blooming” where vessel is obscured by intensity of calcium signal causing false-positive results.

Question 19

Interpret calcium score > 400

Answer 19

High risk - start aspirin and statin, consider functional assessment

Question 20

What are the two domains important to consider when using cardiac imaging to assess for ischaemic heart disease?

Answer 20

Coronary anatomy (anatomical study)
?Ischaemic (functional study)