Long-term form and function of neoesophagus after experimental replacement of thoracic esophagus with nitinol composite artificial esophagus.

Attempts were made to observe long-term form and function of neoesophagus with three pigs that survived for more than 42 months after Nitinol composite artificial esophagus replacement. The neoesophagus was shorter in length than resected esophagus (shorten rate 13.9 +/- 3.1) and thinner than normal esophagus (thickness rate 53.8 +/- 5.5). Esophagography and endoscopic findings indicated that the neoesophagus was dilatation of cystic form, and there was not autonomic peristalsis or constrictive motion. Microscopical findings showed that the wall of the neoesophagus consisted of fibrous connective tissue and esophageal mucosa.These results suggest that the long-term neoesophagus is a stratified squamous epithelium cover scar tissue tube. Although it does not have peristaltic function, experimental pigs can survive long-term with the neoesophagus.

Polyester connecting ring improves outcome in nitinol composite artificial esophagus.

In a previous study, we replaced a thoracic esophagus with nitinol composite artificial esophagus. Two major problems of anastomotic leakage and early sloughing of the grafted prostheses were noted. We have developed a new type of nitinol composite artificial esophagus with polyester connecting ring, and in this study, we test the effectiveness of replacing a thoracic esophagus with this new type of tube. We experimented with two groups: with polyester connecting ring (experimental) and without (control). The shedding time of artificial esophagus in the experimental group was significantly delayed compared with the control group (127.2 +/- 51.8 days vs. 27.6 +/- 15.7 days, respectively, p < 0.05). The incidence of the two major postoperative complications in the experimental group was significantly decreased compared with the control group: anastomotic leakage (0% vs. 33.3%, respectively, p < 0.05) and severe neoesophageal stenosis after prostheses sloughing (10% vs. 50%, respectively, p < 0.05). The long-term survival rate (>6 months) in the experimental group was significantly increased compared with the control group (100% vs. 10%, respectively, p < 0.05). These results suggest that the polyester connecting ring improves outcome of replacement of the thoracic esophagus with nitinol composite artificial esophagus.