Additional Study Information: This study is for patients with Gastroesophageal Reflux Disease or GERD which may cause reflux or heartburn. Symptoms are often caused by a weak valve, or sphincter, between the esophagus (the swallowing tube that leads from your mouth to your stomach) and the stomach. This structure is called the lower esophageal sphincter (LES). Normally, when liquid and food pass through the esophagus, it opens to let food and drink enter the stomach, then the valve closes. When the sphincter is weakened, it can lead to backflow of stomach contents and acid into the esophagus, causing symptoms such as heartburn and regurgitation. The objective of this study is to investigate if electrical stimulation delivered to your LES is safe and will improve LES muscle tone, which could improve GERD symptoms.