Blood Pressure

Jun 1 2008 Dr Gareth Smith

Family Casebook

BLOOD pressure is determined by two things - how forcefully the heart pumps blood around the body and how well the blood passes through the arteries.

If the arteries are narrowed or don't relax properly then the heart has to pump harder to get the blood through and the pressure goes up.

If they are too relaxed, there is not enough blood or the heart can't pump efficiently, the pressure drops.

Blood pressure is recorded as two numbers. The first larger number is known as the systolic pressure. This is the peak pressure of blood pumping round the body.

The second number is the diastolic pressure and is the lowest pressure of blood when the heart is relaxed.

As we get older, it is normal for blood pressure to rise a little due to loss of elasticity in the walls of the arteries. But there are also medical conditions that cause fluctuations in the pressure.