You will be asked to perform a brief assessment (fill in a safety Cardiac Magnetic Resonance form) and get changed into a gown (there is a private changing area for this). A small cannula (drip) is inserted in to a vein in the arm by an experienced doctor/technician. This allows a small amount of a dye to be given as part of the scan itself. This dye is called gadolinium; it is very widely used and usually has no side effects at all; very occasionally (less than 1/100 times) it causes a temporary mild headache or nausea. MRI scans are completely safe and used commonly all over the world in patients with cardiac pathologies. The scanner is noisy but not at all painful. Some people experience feelings of claustrophobia during the scan, but there is constant contact via an intercom system so you can request the study to be be paused at any time.