Dr Simon Kennon MB ChB, FRCP, MD Consultant Cardiologist

High Blood Pressure

The heart is a muscular pump: the heart muscle contracts to pump blood around the body. This keeps the arteries and veins full with blood and generally a pressure of 100-140 / 50-80mmHg is required to supply the organs of the body with enough oxygen and nutrients. The first figure is the systolic blood pressure, which is the pressure of the blood when your heart contracts to pump blood. The second number is diastolic blood pressure, the pressure in the arteries when the heart relaxes (in order to fill up with blood).

Causes: Low blood pressure has a variety of potential causes including blood loss, heart failure and sepsis. There are severalcauses of high blood pressure, relating to kidney function or hormone levels. Usually, however, there is no specific cause but we know that you are more likely to have high blood pressure as you get older and if you are of African or Caribbean descent. Additionally high blood pressure is more likely if you are overweight, if you drink a lot of alcohol or coffee, and if you eat a lot of salt.


Generally high pressure doesn’t cause symptoms although very high blood pressure can cause headaches. Longstanding high blood pressure, however, increases the likelihood of heart attacks, heart failure, strokes and kidney failure. This is why your blood pressure should be monitored and treated if it becomes persistently elevated.


There are several alterations to your lifestyle (“lifestyle measure”) you can make to reduce your risk of high blood pressure and to reduce your blood pressure if it is elevated. These include exercising; eating a well balanced diet rich in fruit and vegetable; losing weightif you are obese or overweight; avoiding excess salt, caffeine, alcohol. If your blood pressure remains elevated despite these lifestyle modifications,or if your blood pressure is markedly elevated, blood pressure lowering tablets may be required. Smoking makes blood pressure lowering tablets less effective as well as being a direct cause of heart attacks and strokes. Common types of blood pressure lowering tablets are: ACE inhibitors (Angiotensin Converting Enzyme); ARBs (Angiotensin 2 Receptor Blockers); calcium channel blockers; diuretics; alpha blockers and beta blockers