The word “syncope” may sound like a complicated medical condition, but syncope simply means to faint. Fainting or passing out is a loss of consciousness for a brief period of time. Presyncope is the term used to describe the lightheaded feeling that a person experiences right before they faint. While fainting is usually nothing to worry about, it can be a warning sign of something more serious (especially if it keeps happening).


Syncope Symptoms

Syncope is characterized by a temporary loss of consciousness, and it is usually very brief in duration (seconds or minutes). Other accompanying symptoms can include feeling lightheaded, dizzy or drowsy; unsteadiness; headache; and vision changes. It happens when blood flow to the brain drops suddenly.


Causes of Syncope

There are several types of syncope:

  • Reflex Syncope (includes vasovagal syncope and situational syncope)
  • Cardiac Syncope
  • Neurologic Syncope
  • Orthostatic Hypotension (low blood pressure while standing)
  • Postural Orthostatic Tachycardia Syndrome (elevated heart rate when standing)


Reflex syncope is by far the most common cause of fainting. It occurs when blood pressure drops suddenly in response to a trigger. This sudden low blood pressure results in less blood flow to the brain, causing a loss of consciousness. There are many potential triggers, but common ones include:

  • Dehydration
  • Standing up too quickly
  • Standing for long periods
  • Emotional response to a stressful event or trauma (e.g., seeing blood, medical procedures, traumatic news, car accident)
  • Anxiety, emotional stress or fear
  • Hyperventilation
  • Overexertion
  • Intense coughing
  • A tight collar or neck twist that puts pressure on the carotid artery
  • Urination (occurring in men while standing)


Cardiac syncope is fainting caused by cardiovascular conditions. Some of the more common causes of cardiac syncope are:

  • Abnormal heart rhythm (arrhythmia)
  • Aortic dissection
  • Aortic valve stenosis
  • Heart conditions affecting blood flow in the heart
  • Heart failure
  • Valve disease


Neurologic syncope is caused by neurological conditions. This includes a transient ischemic attack (also called a “mini-stroke”), stroke and seizures.


Diagnosis and Treatment

Your doctor will collect detailed information about your symptoms, how often they occur and in what situations. In addition to a physical exam, diagnostic tests may be used to determine the cause. These can include:

  • Blood Tests
  • CT Scan
  • Echocardiogram
  • Electrocardiogram
  • Electrophysiology Study
  • Exercise Stress Test
  • Holter Monitor or Event Monitor
  • Tilt Table Test


Treatment depends on the underlying cause of the syncope. In many cases, treating the cause will resolve further fainting episodes. For example: If the cause is an arrhythmia, a pacemaker (an implantable cardioverter-defibrillator) or catheter ablation may be used to restore regular heart rhythms. In other cases, medication and/or lifestyle changes may be all that are required to avoid further occurrence of syncope.


Although most causes of syncope are not serious, it is important to get a full evaluation in case it is caused by an underlying health condition. If syncope occurs with cardiac arrest, call 911. Begin CPR immediately, or use a defibrillator if available.


The team at Advanced Cardiovascular Specialists consists of North Louisiana’s leading experts in cardiovascular care. For more information or to schedule an appointment, please call our office at (318) 798-9400.