Final answer:
Mr. Gonzalez has been admitted for heartburn due to intermittent chest pain with substernal burning.
Step-by-step explanation:
Mr. Gonzalez has been admitted for heartburn because he has intermittent chest pain with substernal burning. Heartburn is a painful burning sensation in the chest caused by stomach acid backing up into the esophagus. This is often experienced as a burning sensation in the vicinity of the heart, but it is not related to the actual heart. The sphincter between the esophagus and stomach may be weak or relax inappropriately, allowing stomach contents to flow into the esophagus, causing the burning sensation of heartburn.