Dr. M.J. Bazos, MD. Patient Handout

About Your Diagnosis

Syncope (pronounced sink-o-pee) means fainting. The term is often used for near fainting or lightheadedness. Syncope can have many causes but is generally related to insufficient blood flow (and therefore decreased oxygen delivery) to the brain. Damaged or stiffened blood vessels may reduce blood flow. Reduced blood flow also can be caused by an arrhythmia (abnormal heart rhythm) that disrupts the normal beating of the heart. Low blood pressure, inefficient pumping by the heart because of heart disease (heart failure), or heart valve abnormalities may cause syncope. Dehydration, anemia (low red blood cell count in the blood), low blood oxygen from lung disease, and some medications (especially medications for lowering blood pressure) can cause syncope. Hyperventilation, low blood sugar, and some neurologic conditions are noncardiac causes that must be addressed. Venous pooling (blood collecting in the veins in the lower body from the effects of gravity) or straining maneuvers (Valsalva) may prevent blood from moving up to the brain when needed. Vasovagal syncope refers to overstimulation of the vagus nerve. This causes reflex lowering of blood pressure through opening of more blood vessels. This may occur with anxiety, pain, urination, or coughing.

Living With Your Diagnosis
For a healthy person a single episode of syncope that resolves by itself usually requires no attention. Multiple episodes or episodes among persons with cardiovascular disease require further evaluation. The physician performs a physical examination and electrocardiogram (ECG) and takes the blood pressure in different positions (lying, sitting, standing, after exercise). Tilt-table testing sometimes is ordered to check for symptoms of syncope in different positions. Blood glucose and hematocrit (blood count) may be checked. A Holter monitor is a device that is worn for continuous monitoring of heart rhythm and may be used to help make the diagnosis.

Management of syncope depends on the cause. If cardiac output (blood being pumped out) is low, the cardiac condition must be evaluated. The most common cause of a single event is a lightheaded sensation from hyperventilating or standing up too fast. The most common causes of frequent episodes of syncope are related to hypotension (low blood pressure) or cardiac disease. Lowering of blood pressure with changes in position is called orthostatic hypotension. Any medications believed to be causing the condition are discontinued on a trial basis. All illnesses and medical conditions should be managed. Blood pressure monitoring is recommended.

The DOs
•Record the setting of episodes of syncope; for example, it happens when you suddenly stand from a seated position.
•Ensure a proper, regular diet and adequate fluid intake, because these are essential to avoiding syncope caused by low blood sugar and dehydration.
•Sit or lie down if you feel faint, because this helps improve blood flow to the brain. Drink cool water once you are able to drink. Eat something to help replenish glucose if you have a history of low blood sugar.

The DON’Ts
•Avoid situations known to aggravate your symptoms.

When to Call Your Doctor
•If episodes of syncope become more frequent or do not respond to home treatment.
•If you have syncope and chest pain, shortness of breath, or a history of heart disease.