Polytetrafluoroethylene-covered stent grafts for TIPS procedure: 1-year patency and clinical results

Polytetrafluoroethylene (PTFE)-covered stent grafts appear to have the potential to improve TIPS patency, but data available are few and controversial. The aim of this prospective nonrandomized trial was to assess TIPS safety and 1-yr patency with a new commercially available PTFE-covered stent graft in comparison with a group of historical controls treated with conventional stents.

Between July 1992 and December 1999, 87 consecutive cirrhotics underwent TIPS with conventional stents, while from January 2000 to November 2001, 32 consecutive cirrhotics were treated with PTFE-covered stent grafts. All patients were followed by the same medical team according to a prospective protocol for a diagnostic work-up and a surveillance strategy.

The two groups were comparable for age, sex, etiology, and severity of cirrhosis. The 1-yr probability of remaining free of shunt dysfunction tended to be higher in the covered stent group: 76.3% (95% CI = 58.7-93.9%) versus 57.5% (95% CI = 46.6-68.4%); log rank test: p = 0.055. However, stenoses inside the stent were significantly higher in patients with bare stents (88% vs 17%), while stenoses at the hepatic or portal vein were more frequent in PTFE-covered stent-graft group (50% vs 9% and 33% vs 3%, respectively), (chi2 = 15.42; df = 2.0; p = 0.0004). Stenoses inside the covered portion of the stent did not occur. One-year cumulative rebleeding, encephalopathy, and survival were similar.

PTFE-covered stents are able to solve pseudointimal hyperplasia within the stent tract, but have a high incidence of hepatic or portal vein stenosis. Improvements in stent design and insertion techniques are necessary to fully achieve the potential benefit of this new device.