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Macular oedema

Macular oedema is used to describe an eye problem that can be caused by high blood pressure. It occurs when small blood vessels at the back of your eyes burst or rupture, causing a build-up of fluid in areas around the blood vessels. If it is not treated, it can affect your eyesight.

See our information on eye tests

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Malignant hypertension

This form of high blood pressure is also known as “accelerated hypertension”. It is a rare condition where your blood pressure rises rapidly. People with malignant hypertension often require emergency treatment in hospital, where their blood pressure is brought down over a number of days.

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Mercury manometer

This is a device used for measuring blood pressure. It consists of a glass column filled with mercury, which is attached to a cuff that goes around your arm. As the cuff is inflated, the air pressure pushes the mercury up the tube; as the cuff is deflated, the mercury falls. Your blood pressure is then read off the column.

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This is a symbol which stands for “millimetres of mercury”. This is the unit of measurement for blood pressure, so when your reading is 120 over 80, for example, it is really 120 millimetres of mercury over 80 millimetres of mercury or 120/80mmHg.

See our information on what is blood pressure?

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Monounsaturated fats

These are the best type of fat to eat to help reduce the amount of bad cholesterol in your blood and raise the level of good cholesterol in your body. Good sources of monounsaturated fats are rapeseed, groundnut and olive oils.

See our information on fats and cholesterol

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MRI (magnetic resonance imaging)

This is a type of scan that uses a very strong magnetic field to produce a picture of your bones and organs. MRI can be used to see whether there is any damage to your organs or, sometimes, to see if they are working properly.

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Myocardial infarction

A medical term used to describe a heart attack.

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Myocardial ischaemia

A medical term used to describe angina.

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A medical term used to describe kidney disease.

See our information on kidney disease

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Nocturnal dip in blood pressure

Normally your blood pressure will be highest first thing in the morning and will steadily fall throughout the day and further at night. This drop at night is known as the nocturnal dip.

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A hormone produced by your body that can make some blood vessels become more narrow. This effect raises your blood pressure.

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NSAIDs (Non-steroidal anti-imflammatory drugs)

NSAIDs are commonly used painkillers, for example ibuprofen. These medicines can raise your blood pressure, so it is important to avoid them if you have high blood pressure.

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Supporting You

From discussion forums for sharing experiences, to email updates of the latest blood pressure news, we have a range of support available

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