Prevention of Portal Hypertension Complications Beyond Primary <scp>TIPS</scp> Indication Is Independent of Endoprosthesis Under‐Dilation

BACKGROUND & AIMS: Under-dilated trans-jugular intra-hepatic porto-systemic shunt (U-TIPS, ≤ 7 mm) effectively controls portal hypertension (PH) complications that placed the indication to TIPS while reducing the incidence of hepatic encephalopathy. However, TIPS efficacy in preventing additional PH-complications is reported only for standard endoprosthesis dilation (≥ 8 mm, S-TIPS). This study evaluated whether U-TIPS provides protection comparable to S-TIPS against PH-complications beyond the initial indication, independent of achieving guideline-defined hemodynamic targets. METHODS: Patients treated for refractory ascites (RA) or secondary prophylaxis of PH-related bleeding (PHRB) were included. Adequate hemodynamic response (AHR) was defined as post-TIPS PCPG < 12 mm Hg in RA, and < 12 mm Hg or reduction ≥ 50% in PHRB. Porto-caval pressure gradient (PCPG) values outside these criteria were deemed an inadequate response (IHR). Post-TIPS spontaneous bacterial peritonitis, acute renal injury hepatorenal syndrome-related, hepatic hydrothorax, need for paracentesis, and bleeding, were assessed individually and as a composite endpoint over one year. RESULTS: Of 358 patients, 257 (72%) received U-TIPS and 101 (28%) S-TIPS. The incidence of at least one post-TIPS event was higher in S-TIPS vs. U-TIPS (14% vs. 6%, p = 0.022), with no significant difference between AHR and IHR groups (9% vs. 7%, p = 0.543). On multivariable analysis, S-TIPS (OR 3.13, 95% CI 1.38, 7.21, p = 0.006), Child-Pugh class B (OR 11.6, 95% CI 2.14, 217, p = 0.021) and C (OR 14.4, 95% CI 1.17, 343, p = 0.042), higher MELD score (OR 1.20, 95% CI 1.09, 1.32, p < 0.001) were independently associated with post-TIPS events. CONCLUSIONS: U-TIPS provides non-inferior protection against other PH-complications irrespective of achieving hemodynamic efficacy targets.