Your doctor may recommend a tilt table test to evaluate the cause of syncope. A tilt table test may also be recommended if he or she suspects that vasovagal syncope is responsible for your fainting and needs additional testing to confirm the diagnosis.

Vasovagal syncope happens when the part of your nervous system that controls blood pressure and heart rate suddenly lowers your heart rate and blood pressure for a short time. Then, less blood flows to your brain and you may faint. This kind of syncope is also called neurocardiogenic syncope, reflex syncope and the common faint.

With vasovagal syncope, you may or may not have warning signs, such as weakness, sweating, blurred vision or nausea. Vasovagal 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 is more common while standing but also occurs while sitting or lying down.

Jan. 12, 2018