Abnormal blood pressure usually indicates high blood pressure, as low blood pressure is not cause for concern unless noticeable symptoms are also present, states the American Heart Association. High blood pressure, meanwhile, can cause a variety of maladies, including vascular weakness, vascular scarring and increased risk of blood clots.
Low blood pressure accompanied by dizziness, fainting, lack of concentration, dehydration or fatigue is a sign of an underlying cause, according to the American Heart Association. Blurred vision, nausea, shallow breathing, depression and clamminess are also indicators. Pregnancy, severe infection, endocrine issues, prolonged bed rest and heart problems can be underlying causes of abnormally low blood pressure. Patients experiencing any of these symptoms should contact a health care professional as soon as possible.