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Systolic Blood Pressure
Hypertension.me Explains Systolic (Top Number) and Diastolic (Bottom Number) Blood Pressure

What is Systolic Blood Pressure and why is it called the "Top Number"?
Why are there two numbers and what do they mean?    
Systolic blood pressure is the pressure of the blood stream being generated to your arteries by the pumping action of your heart. By placing a blood pressure cuff around your arm which envelops the brachial artery on the inner aspect of your upper arm, your doctor compresses the artery (temporarily, we hope)  above which the heart cannot overcome.  As the pressure on the cuff is released (which you hear as a hissing sound), the pressure on the brachial artery is lowered to a point at which the heart can pump blood past the blood pressure cuff.  At this point, the doctor can hear a whooshing noise through the stethocope placed over the brachial artery point just above your elbow.  That first sound represents the systolic blood pressure or top number. 


There are up to five different sounds, known as Korotkoff Sounds, that your doctor is listening to as he continues to release or lower the pressure in the blood pressure cuff.  The last sound heard is the Diastolic Blood Pressure, or "Bottom Number", after which the blood flow is smooth and silent.  These sounds are similar to having water coming out of a hose (without a nozzle).  There would be very little sound until you place your thumb over the end of th hose and create a jet stream "whooshing" sound as you compress the end of the hose and which lets up as you remove your thumb from the end of the hose and allow the water to run smoothly through the hose.  Analogies are abundant on this site and are offered at no extra charge.   Systolic Blood Pressure represents the resistance the heart must overcome to adequately pump blood to go where it should go.  If you use the term, Systolic Blood Pressure instead of '"top number", your doctor will realize you understand Blood Pressure at a more sophisticated level. Maybe then he will stop hurting you by not pumping the blood pressure cuff so high (or at least he will know that you understand why he is doing it).
->Diastolic Blood Pressure