Effect of initial stent position on patency of transjugular intrahepatic portosystemic shunt

Abstract

Aim: To evaluate the effect of initial stent position on transjugular intrahepatic portosystemic shunt (TIPS).

Methods: We studied 425 patients from January 2004 to January 2015 with refractory ascites or variceal bleeding who required TIPS placement. Patients were randomly divided into group A (stent in hepatic vein, n = 57), group B (stent extended to junction of hepatic vein and inferior vena cava, n = 136), group C (stent in left branch of portal vein, n = 83) and group D (stent in main portal vein, n = 149). Primary unassisted patency was compared using Kaplan-Meier analysis, and incidence of recurrence of bleeding, ascites and hepatic encephalopathy (HE) were analyzed.

Results: The mean primary unassisted patency rate in group B tended to be higher than in group A at 3, 6 and 12 mo (P = 0.001, 0.000 and 0.005), and in group D it tended to be lower than in group C at 3, 6 and 12 mo (P = 0.012, 0.000 and 0.028). The median shunt primary patency time for group A was shorter than for group B (5.2 mo vs 9.1 mo, 95%CI: 4.3-5.6, P = 0.013, log-rank test), while for group C it was longer than for group D (8.3 mo vs 6.9 mo, 95%CI: 6.3-7.6, P = 0.025, log-rank test). Recurrence of bleeding and ascites in group A was higher than in group B at 3 mo (P = 0.014 and 0.020), 6 mo (P = 0.014 and 0.019) and 12 mo (P = 0.024 and 0.034. Recurrence in group D was higher than in group C at 3 mo (P = 0.035 and 0.035), 6 mo (P = 0.038 and 0.022) and 12 mo (P = 0.017 and 0.009). The incidence of HE was not significantly different among any of the groups (P = 0.965).

Conclusion: The initial stent position can markedly affect stent patency, which potentially influences the risk of recurrent symptoms associated with shunt stenosis or occlusion.

Keywords: Liver cirrhosis; Portal hypertension; Stent position; Transjugular intrahepatic portosystemic shunt.

Figure 1

Stent was positioned as described in the study design for each group. A: Ideal position of the stent endpoint in the TIPS procedure. The transverse arrow indicates the proximal end of the stent at the junction of the hepatic vein and IVC. No angle was formed between the stent and left branch of the portal vein. The proximal end of the stent was located at the junction of the hepatic vein and IVC and did not cause stenosis or occlusion, and did not affect liver transplantation. The arrow pointing up indicates the distal end of the stent located at the left branch of the portal vein. The stent was in parallel to the direction of blood flow, therefore, it was not easy to cause stent stenosis or occlusion; B: The proximal end of the stent in the hepatic vein in the TIPS procedure. The arrow indicates the proximal end of the stent in the hepatic vein. The stent endpoint caused stenosis or occlusion due to blood flow shear force and vascular intimal hyperplasia; C: Distal end of the stent in the main hepatic vein in the TIPS procedure. The arrow indicates the distal end of the stent in the main hepatic vein in the transjugular intrahepatic portosystemic shunt procedure. The distal end of the stent was prone to stimulate the blood vessel wall and interfered with the portal vein blood flow. The stent endpoint caused stenosis or occlusion due to blood flow shear force and vascular intimal hyperplasia. TIPS: Transjugular intrahepatic portosystemic shunt; IVC: Inferior vena cava.

Figure 2

Primary unassisted patency (A), recurrent variceal bleeding (B) and recurrent ascites (C) in four groups of patients with transjugular intrahepatic portosystemic shunt. A: The median shunt primary patency time was 5.2 mo in group A and 9.1 mo in group B (95%CI: 4.3-5.6, P = 0.013, log-rank test). The median shunt primary patency time was 8.3 mo in group C and 6.9 mo in group D (95%CI: 6.3-7.6, P = 0.025, log-rank test); B: The median time to recurrence of bleeding was 5.2 mo in group A and 7.4 mo in group B (95%CI: 3.2-8.5, P = 0.016, log-rank test). The median time to recurrence of bleeding was 8.7 mo in group C and 6.3 mo in group D (95%CI: 3.2-8.5, P = 0.011, log-rank test); C: The median time to recurrence of ascites was 5.9 mo in group A and 10.4 mo in group B (95%CI: 6.5-9.2, P = 0.007, log-rank test). The median time to recurrence of ascites was 9.1 mo in group C and 6.8 mo in group D (95%CI: 6.5-9.2, P = 0.009, log-rank test).