Observational studies, including randomised controlled trials (RCTs), that compared TIPS with PTFE-covered stent-grafts against with a control group with bare stents were eligible. Outcomes comprised shunt dysfunction (>50% reduction of the lumen of the shunt at portography, a portalsystemic pressure gradient >12mmHg or a combination of both), primary patency (absence of shunt insufficiency without intervention during TIPS surveillance), hepatic encephalopathy (Parsons-Smith criteria) and survival.
The mean age of patients in the included studies ranged from 53 to 59 years of age. Most patients by far in all studies were male. In all studies except one the patient population had cirrhosis; in the other study they had Budd-Chiari syndrome. TIPS patency surveillance involved ultrasonography in all studies, together with angiography or portography.
The authors did not report how many reviewers performed the study selection.