Acid reflux happens when stomach acid backs up and irritates the sensitive tissue of the food pipe (esophagus), giving you heartburn. It has nothing to do with the heart, but is named as such because the burning pain is often located in the vicinity of your heart.
It is usually caused by fatty and or acidic foods and can be made worse by lying down immediately after meals. For many people it gets worse with stress. Antacids that neutralize these stomach acids can ease the occasional heartburn.
Though, if it occurs on a regular basis, heartburn may be a symptom of GERD (gastroesophageal reflux disease) or other pathologies and should be checked by a medical practitioner.
In Chinese Medicine, acid reflux means that the ‘Qi’, flows against its intended direction within the body. This ‘rebellious’/counterflow Qi is usually dealt with by acupuncture points and herbs that promote movement of Qi, and working on any underlying pathologies that facilitate rebellious Qi.