Low Pulse Pressure

We are often asked about pulse pressure and have therefore created a short article to explain what it means.

Pulse pressure

Pulse pressure is the difference between the systolic (top) and diastolic (bottom) numbers of your blood pressure. So, if your blood pressure is 120/80, your pulse pressure is 40 mmHg.

High (or wide) pulse pressure

A pulse pressure is considered high when it is more than 100mmHg. This can occur in endurance athletes, older people as blood vessels become less elastic (‘hardening of the arteries’) and in some medical conditions including anaemia, overactive thyroid and faulty heart valves.

Low (or narrow) pulse pressure

A pulse pressure is considered low when it is less than 25% of the systolic blood pressure. For example, if your systolic blood pressure is 120, a pulse pressure of under 30mmHg would be low. Low pulse pressure can occur when there is a reduction in the volume of blood pumped out in each heartbeat and is seen when there is excessive blood loss and a variety of heart conditions. Low pulse pressure can also occur in people with faulty autonomic control of blood pressure, for example in the ‘vasodepressor’ form of low blood pressure when blood vessels are unable to narrow when we stand up. Blood pools in the abdominal cavity and limbs, and consequently less blood is returned to the heart. With less blood available to pump around the body, blood pressure drifts down on standing and the pulse pressure becomes smaller.

After the blood pressure drops, the heart rate can subsequently increase to compensate for the low blood pressure; this vasodepressor form of low blood pressure can sometimes be mistaken for PoTS. The treatment for this vasodepressor form of vasovagal syncope (or presyncope) is very similar to the treatment of PoTS.