Blood Pressure: Understanding the Basics: Blood pressure (BP) measures the force of blood against the walls of blood vessels. Your BP reading consists of two numbers: - The top number is the systolic blood pressure, which indicates the pressure in your arteries when your heart beats or contracts. - The bottom number is the diastolic blood pressure, which reflects the pressure in your arteries between heartbeats, when your heart is at rest. Healthcare providers measure blood pressure in millimeters of mercury (mmHg). What is low blood pressure (hypotension)? Low blood pressure, also known as hypotension, occurs when the force of blood against the walls of the arteries is too low. Blood pressure is measured in millimeters of mercury (mm Hg), and low blood pressure is typically defined as a reading below 90/60 mm Hg. **What is High Blood Pressure (Hypertension)?**   High blood pressure, or Hypertension, is the force with which blood is pumped from the heart into the arteries. W...