Dr. M.J. Bazos, MD.
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
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
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.
•Record the setting of
episodes of syncope; for example, it happens when you suddenly stand from a
•Ensure a proper,
regular diet and adequate fluid intake, because these are essential to avoiding
syncope caused by low blood sugar and
•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.
known to aggravate your
When to Call Your
•If episodes of syncope
become more frequent or do not respond to home
•If you have syncope and
chest pain, shortness of breath, or a history of heart