Localized irregularity of the mucosa was noted in the z-line and gastroesophageal junction. should i be worried?

Any irregularity of the esophageal mucosa is a cause for concern and the gastroenterologist is the specialist I turn to for the evaluation, advice,any treatment and follow-up. Concern here would be for metaplasia or Barrett's esophagus. Hopefully the evaluation may show neither.

No, this is a fairly common description of the junction between the stomach and the esophagus. It may be an indication of Gerd. I would speak with the gastroenterologist to see if he or she wants you to be on therapy for Gerd. Anti-reflux measures can also help. Good luck.