Health and Medicine

Diagnostic Equipment, Tests, and Techniques

What is the meaning of the numbers in a blood pressure reading?

When blood is forced into the aorta, it exerts a pressure against the walls; this is referred to as blood pressure. The upper number, the systolic, measures the pressure during the period of ventricular contraction. The lower number, the diastolic, measures the pressure when blood is entering the relaxed chambers of the heart. While these numbers can vary due to age, sex, weight, and other factors, the normal blood pressure is around 110/60 to 140/90 millimeters of mercury.

Is there a name for the heart-monitoring machine that people sometimes wear for a day or two while carrying on their normal activities?

A portable version of the electrocardiograph (ECG) designed by J.J. Holter is called a Holter monitor. Electrodes attached to the chest are linked to a small box containing a recording device. The device records the activity of the heart.


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