What should you know about a heart MRI scan?

During the scan, magnetic fields and radio waves produce images while the heart beats. The team may assess chamber size, pumping movement, valves, blood flow and the appearance of heart muscle. Some examinations use contrast to make tissue differences clearer. MRI does not use ionising radiation, but the scanner is noisy and the examination requires you to lie still, sometimes holding your breath for short periods. The report is interpreted with your symptoms and other test results.

Tell the imaging team about pacemakers, implanted devices, metal fragments, kidney problems, allergies, pregnancy or claustrophobia before attending. Follow instructions about eating, caffeine and medicines because some heart MRI protocols use a medicine that changes heart rate or blood flow. Remove metal items and bring details of any implanted device. Ask whether contrast is planned and how long the visit may take.

Do not wait for a routine MRI appointment if you develop severe chest pain, sudden breathlessness, fainting, blue lips, new weakness or a fast or irregular heartbeat with dizziness. Seek emergency help for these symptoms. Report a rash, swelling or breathing difficulty after contrast immediately.

Ask what the MRI is intended to answer, whether contrast or a stress medicine will be used, and when the report will be discussed. Check whether your implanted device is suitable for the scanner and what alternatives exist if you cannot complete the examination.