While no relationship exists between the severity of heartburn and the development of Barrett 's esophagus , a relationship does exist between chronic heartburn and the development of Barrett 's esophagus .
SCONJ DET NOUN VERB ADP DET NOUN ADP NOUN CCONJ DET NOUN ADP PROPN PART NOUN , DET NOUN AUX VERB ADP ADJ NOUN CCONJ DET NOUN ADP PROPN PART NOUN .