Your doctor may recommend a tilt table test if he or she suspects that neurocardiogenic syncope is responsible for your fainting and needs additional testing to confirm the diagnosis.
Neurocardiogenic syncope happens when the part of your nervous system that controls blood flow changes your heart rate and lowers your blood pressure for a short time. Then, less blood flows to your brain and you may faint. This kind of syncope is also called vasovagal syncope, reflex syncope, and the common faint.
With neurocardiogenic syncope, you may or may not have warning signs, such as skin paleness, weakness, sweating, blurred vision or nausea. Neurocardiogenic syncope often is a response to something like the sight of blood or an upsetting situation. But it can happen with no clear trigger. This kind of syncope happens when you are standing or sitting.