Insights

What do blood pressure numbers mean?

The top and bottom numbers describe pressure at different parts of a heartbeat.

What does it mean?

The top number, called systolic pressure, measures pressure when the heart contracts. The bottom number, called diastolic pressure, measures it between beats. A reading written as 128/78 is spoken as “128 over 78.” The unit is millimeters of mercury, or mm Hg. Source: American Heart Association: blood pressure readings (opens in a new tab).

How does it fit into the conversation?

One reading is a snapshot. Your clinician uses the pattern of readings and your circumstances when assessing blood pressure. Home and office readings can differ; accurate technique and a properly fitting cuff help make a home log useful. Source: American Heart Association: home blood pressure monitoring (opens in a new tab).

What should I look for in my records?

Bring the actual readings with their dates and times, the device you use if requested, and the medication plan already prescribed. A useful question is: “Which readings are you using to judge how my current plan is working?”

Questions for your treating team

  • What blood pressure range have we agreed for me?
  • Can you check my cuff and measurement technique?
  • When and how often should I measure at home?
  • Which readings or symptoms should lead me to call, and whom should I contact?

Want help understanding your own records?

Our $350 educational review focuses on one cardiology question and up to 40 relevant pages. It includes a 30-minute conversation, a written explanation, an organized medication list, and questions for your treating team. Available to eligible adults in New York.

$350 · Phone or videoRequest a review