Low Blood Pressure

Noel Peterson, MD FACC FASE

Eastern Cardiology, Greenville NC

In general, physicians are focused on diagnosing and treating high blood pressure, but in some instances people can be affected by low blood pressure. I am going to discuss the significance of low blood pressure (hypotension), including signs and symptoms and when to worry about having low blood pressure.

Q: Everyone talks about high blood pressure as a problem. Why should I worry about low blood pressure?

Blood pressure typically changes considerably throughout the day and night. This variability can be often be attributed to physical activity, emotional stress, or other factors such as pain but frequently without any obvious cause. In general, as the population grows older and more obese blood pressure increases. Therefore, having a “low blood pressure” is often normal in younger people.  Certain acute medical conditions and other medical conditions can sometimes cause hypotension.

Q: What BP ranges classify as low blood pressure readings?

Normal or optimal blood pressure is typically defined as systolic (top number) <120 and diastolic (bottom number) <80. There is not really a certain blood pressure that is classified as too low – it depends on multiple factors such as age, medical conditions, and physical activity levels to name a few. In general, your blood pressure is too low if it makes you feel symptomatic, including lightheadedness, dizziness, weakness, or fainting.

Q: What heart-related problems can occur because of low blood pressure?

Low blood pressure does not typically cause heart-related problems, but it can often be a symptom of an acute heart-related problem such as certain types of heart attacks, aortic dissection, cardiac tamponade, RV infarction – but these conditions have many other symptoms that accompany them.

Q: How can I tell if I may be suffering from low blood pressure?

The main indication is if you are experiencing symptoms such as dizziness, lightheadedness and weakness in conjunction with a low blood pressure. In a normal person when you stand, 500 to 800 ml of blood is displaced to the abdomen and lower extremities. This causes an abrupt drop in venous return to the heart. This triggers a reflex that results in our bodies ability to maintain a stable blood pressure on standing.

One of the more common types of hypotension is orthostatic hypotension, which is defined as 20mmHg drop in systolic blood pressure or 10mmHg drop in diastolic blood pressure within 3 minutes of standing, results from a defect in any portion of this blood pressure control system. Associated symptoms include lightheadedness, dizziness, blurred vision, weakness, palpitations, tremulousness and syncope. These symptoms tend to be worse in early mornings or after meals or exercise. Medications that cause volume depletion or result in vasodilation, such as diuretic (fluid pills) or blood pressures medications are the most common cause of orthostatic hypotension and certain neurologic conditions and nervous system dysfunctional disease are also causes.

In most instances low blood pressure is not a cause for concern if you are not experiencing any symptoms. If you are experiencing some of the symptoms listed above along with low blood pressure than work with your doctor to see if there is an underlying cause.

Please call to make an appointment. You can reach Dr. Noel Peterson at 252-757-3333 or 252-758-3000. Office information and business hours are listed below