Blood pressure measuring equipment, conceptual artwork. A device that measures blood pressure is called a sphygmomanometer. The display of a digital sphygmomanometer is at centre. It shows a systolic pressure of 165 millimetres of mercury (mmHg). This is higher than the normal range, which is between around 100 and 130mmHg. An analogue sphygmomanometer is at upper right. Blood pressure is an important measure of health. High blood pressure (hypertension) is a risk factor for heart disease and strokes.