How Serious is it?

Too high blood pressure is not dangerous right now.

However, a continuously high blood pressure over 5-10 years increases your risk of having a heart attack or a stroke followed by death or disablement.

The risk of having the two illnesses is strongly increased with people with too high blood pressure. It is however not only blood pressure that increases the risk of having a blood clot. The risk rises with age, is greater with men than with women and greater with people whose parents or siblings have had a blood clot. Smoking, too much fat in the blood, overweight, lack of exercise, too much alcohol and diabetes also increase the risk of having a heart attack or a stroke.

Further reading on Hardening of the arteries (arteriosclerosis)