The Coronary Arteries•The heart is a big muscle so needs a blood supply to work.
•It doesn’t use the blood inside the heart it has it’s own blood vessels.
•These arteries are called the coronary arteries and are very important.
A coronary artery
Heart Diseases
•UK’s biggest killer40% of all deaths
www.heartstats.org
240,000PEOPLE DIE OF HEART DISEASE EVERY YEAR!!!!!
What happens to all that fat?
• It can cause chest pain – ANGINA.• It gets bigger and can stop the blood to the
heart – a HEART ATTACK.• OR it can break off and:
– Get stuck on the way to the heart – a HEART ATTACK.
– Get stuck in your lungs – PULMONARY EMBOLISM.
– Get stuck in your brain – a STROKE.
X-Ray Contrast Angiography
• X-RAY– All we see is ribs when we x-ray the heart.
• To see the heart and blood vesselswe inject iodine CONTRAST into a vein which absorbs x-rays like bone.
• Taking pictures of vessels like this is called ANGIOGRAPHY.
Angiography of the coronary arteries
Fat
What the coronary arteries would look like
Nor
mal
With
a p
laqu
e
What we see in x-ray contrast angiography
Vessel wall
Blood
Thin bit where disease is
Nor
mal
With
a p
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e
Ultrasound
• High frequency sound waves.• Put small probe on skin between ribs.• See valves and heart moving.
Which is best?
X-ray Contrast Angiography• Is good for seeing coronary
arteries.• Uses ionising radiation.
• Need to inject iodine contrast dye.
Ultrasound• Is good for seeing the valves
move.• Uses high frequency sound
waves.• Need to look between the
ribs.
Both have their uses but neither is ideal.
Contrast Agent
• If we inject a gadolinium compound (contrast agent) the magnetic field is increased wherever the contrastagent goes.
• The increased magneticfield means that the radiowave comes back more quickly.
Pictures of your thoughts!
• When you use part of your brain, extra blood flows to that part of your brain with more oxygen.
• Oxyhaemoglobin and deoxyhaemoglobin alter the magnetic field, changing how quick the radio waves come back.
Thank you for listening!
Andrew ScottPhD Student (in Physics)
Cardiovascular Magnetic Resonance UnitRoyal Brompton and Harefield NHS Trust.National Heart and Lung Institute, Imperial College.