Syncope is a neurologic condition in which a person temporarily loses consciousness. It may be associated with dizziness -- a sensation of unsteadiness and lightheadedness -- and confusion. As explained by the American Heart Association, syncope often occurs when blood pressure is low and blood supply to the brain is insufficient as a result of the heart's inability to pump enough blood. Some diseases that can cause syncope are cardiac arrhythmias, transient ischemic attacks and orthostatic hypotension.
Transient Ischemic Attacks
A transient ischemic attack is also referred to as a mini stroke. A stroke occurs when blood flow to part of the brain is severely low or interrupted. Brain cells start to die minutes after this happens. A stroke is a medical emergency that requires prompt medical treatment. Transient ischemic attacks produce stroke-like symptoms. They are caused by a temporarily clogged artery that supplies blood to part of the brain. The resulting blood and oxygen deprivation results in symptoms such as syncope, confusion and dizziness. Unlike a stroke, signs of transient ischemic attacks last for a short time and do not cause lasting damage to the brain.
Cardiac Arrhythmia
The heart's pumping action, or beats, occurs in a regular fashion and is enabled by the heart's electrical system. A dysfunction in this electrical system can cause a cardiac arrhythmia, a condition in which the heart beats too fast, too slow or irregularly. The Merck Manuals Online Medical Library notes that the effects of cardiac arrhythmias may be life-threatening or quite harmless. However, during some arrhythmias, the heart may be unable to pump enough blood to the brain, leading to effects such as syncope, dizziness and confusion.
Orthostatic Hypotension
Orthostatic hypotension occurs when a person rises to a standing or upright position quickly. It is an abrupt drop in blood pressure, the force blood exerts against the inner walls of the arteries as it flows through them. This may occur due to the fact that when a person assumes a standing position, blood pools in the legs as a result of gravity. MayoClinic.com explains that dizziness is the most common effect of orthostatic hypotension. Dizziness from this condition may then progress to syncope. Orthostatic hypotension also causes confusion.
References
- American Heart Association: Syncope
- Mayo Clinic: Stroke
- "Lippincott Manual of Nursing Practice Series: Alarming Signs and Symptoms"; Lippincott Williams and Wilkins; 2007
- Merck Manuals Online Medical Library: Abnormal Heart Rhythms
- Mayo Clinic: Orthostatic Hypotension
