3- cardiovascular radiology

Question 1

what are the imaging modalities available for cardiovascular radiology?

Answer 1

• simple radiographs (CXR)
• Angiography (catheter, CT or MRI)
• ultra sound (echocardiography)
• CT
• MRI
• Nuclear Cardiology

Question 2

what are positives and negatives of x-rays?

Answer 2

advantages:
- easy
- immediate

disadvantages:
- radiation
- sometimes non-specific

Question 3

what is cardiothoracic ratio?

Answer 3

ratio of maximum diameter of the heart divided by maximum diameter of the thorax

• normal CTR should be less than or equal to 50%

Question 4

how is chest x-ray taken?

Answer 4

taken with AP (anteroposterior) projection

Question 5

when is a catheter angiography done?

Answer 5

catheter angiography is often performed as a prelude to radiological intervention

Question 6

what are the positives and negatives of angiography?

Answer 6

advantages:
- excellent coronary arterial depiction
- assess anomalies
- assess coronary plaques/stenosis
- assess stents/ CABGs

disadvantages:
- radiation
- invasive
- complications
- may need admission
- contrast allergy/nephropathy

Question 7

what happens in catheter angiogram?

Answer 7

medical procedure used to visualize the blood vessels in the heart
- done following a contrast injection into coronary arteries

Question 8

what are positives and negatives of echocardiography?

Answer 8

advantages:
- immediately available
- functional assessment of the heart
- valvular assessment
- chamber assessment
- no radiation - can repeat without worries!

disadvantages:
- operator dependant
- patient dependant
- incomplete cardiac assessment

Question 9

what are the positives and negatives of cardiac CT following IV contrast?

Answer 9

advantages:
- excellent cardiac anatomy depiction
- non invasive coronary artery assessment
- functional assessment
- chamber assessment
- look at vessels & lungs

disadvantages:
- radiation dose
- resolution still slightly less than catheter angiography
- potential for contrast allergy/nephropathy
- need special CT equipment/expertise

Question 10

what are positives and negatives of cardiac MRI?

Answer 10

advantages:
- no radiation, so no issue with repeat exams
- excellent soft tissue resolution
- anatomical assessment
- gold standard
- functional assessment

disadvantages:
- long imaging times
- claustrophobia
- MRI contraindications
- need special MRI equipment/expertise
- not very useful for coronary arteries at present

Question 11

do MRI images require an injection of contrast?

Answer 11

no but additional images might require gadolinium contrast

Question 12

what can be calculated by cardiac MRI?

Answer 12

cardiac function can be calculated - LV muscle mass & ejection fracture

Question 13

what is cine cardiac MRI?

Answer 13

• This cine examination uses the classic 4 chamber projection and provides a dynamic visual assessment of cardiac function, similar to that obtained by echocardiography
• A cine cardiac MRI series using the 2 chamber projection.
• A cine cardiac MRI series using the short axis projection.

Question 14

what is nuclear cardiology? and what can it be used to assess?

Answer 14

• The cardiac nuclear medicine (isotope myocardial perfusion) study is used to display images of the heart in the three standard projections. It can assess the left ventricular myocardial perfusion, where most cardiac muscle is located.
• In practice, it is often used to determine the impact of coronary artery disease on regional myocardial perfusion. Such information influences whether patients receive medical or surgical treatment for their arterial

Question 15

what is CT pulmonary angiogram?

Answer 15

ensitive and specific diagnostic test for pulmonary embolus, and remains accurate in patients with an abnormal CXR or pre-existing lung disease, situations where V/Q scans are often indeterminate

Question 16

what is a V/Q scan?

Answer 16

an accurate way to diagnose a pulmonary embolus in patients with normal CXR and no pre-existing lung disease. Demonstration of continued ventilation of an area of lung where no flow is present is highly suggestive of PE

Question 17

how is a ventilation/perfusion scan obtained?

Answer 17

obtained in multiple projections, that demonstrate perfusion of different aspects of the lung, so increasing sensitivity for emboli. A normal scan is shown below. Note the large anterior perfusion defect due to the heart

Question 18

what is a useful test for peripheral vascular disease?

Answer 18

Doppler ultrasound - angiographic images are often then obtained to plan surgery or radiological intervention. In the past, this required catheter angiography but non-invasive MR angiography can now provide similar information

Question 19

what does CT cerebral angiography confirm?

Answer 19

• confirms the likely source of haemorrhage, an aneurysm arising from the right middle cerebral artery.
• Such aneurysms can be multiple and the other intracranial vessels must also be scrutinised to exclude further lesions.

Question 20

can you do angiogram of whole body?

Answer 20

yes - with modern MR technology