Transjugular intrahepatic porto-systemic shunt is a commonly used effective procedure in managing cases with complicated portal hypertension with a limitation of being frequently dysfunctional. Other secondary interventions are made to overcome the problem of TIPS dysfunction. TIPS dysfunction may occur due to one of the following reasons: acute thrombosis of the stent, pseudo-intimal hyperplasia, secondary to biliary leaks into the shunt lumen, and intimal hyperplasia in the outflow hepatic vein or inflow PV [15]. Also, the position of the stent within the outflow hepatic vein affects strongly TIPS patency. Blood turbulence and shear stress with increased shunt flow can accelerate pseudo-intimal hyperplasia and lead to shunt dysfunction. Some studies demonstrated that when TIPS extends to hepatocaval junction, it has a better patency rate than when introduced in the hepatic vein [16].
Several interventional modalities have been used to overcome dysfunctional TIPS, including angioplasty and placement of telescoping stent. The best option is the placement of an additional in-stent or telescoping stent after negotiating the site of shunt stenosis or occlusion. This method not only allows for the restoration of the TIPS functions, but it may also be related to the improved shunt patency aided by the reinforcement and the radial strength of the second stent [16]. But if stenotic or occluded shunt appears inaccessible, impassable, or non-amenable to dilatation, the creation of another PS is necessary.
Trans-caval puncture was first described by Haskal et al. in 1996 with cases of inaccessible hepatic veins or in cases where the caudal locations of PV bifurcation were close to hepatic veins [3]. In the study of Luo et al. on 18 patients, they used the trans-caval approach which was difficult in one patient with Budd-Chiari syndrome [17]. In our study, we performed trans-caval puncture on (33/37) (89.2%) patients with Budd-Chiari syndrome and another one with blocked previous shunt and inaccessible hepatic veins. Trans-caval approach was particularly difficult in our patients because the index TIPS was done using the same trans-caval approach making the cava room for the second PS narrower with limited needle control.
Regarding the portal entry, no studies have described the point of entry to the PV although it is a critical point in PS insertion. Because the index TIPS often occupies the right branch PV, the chance to go to PV is limited from the same vein. In our study, we punctured the left PV in 22 patients (59.5%) while we punctured the neck in 13 patients (35.1%) (Fig. 7), and we punctured the right PV in 2 patients. Puncturing the left portal is very difficult because of 2 factors: the first one is that the location is more anterior than that of the right one necessitating bending of the TIPS needle up to 90 degrees. The second one is the short cranio-caudal distance between top of cava to left PV compared to the right PV.
In 1998, Dabos et al. first described a series of 29 patients undergoing the PS insertion, suggesting that the PS patency without further intervention is slightly superior to the patency of the first shunts [18]. In 2006, Helmy et al. described the natural history of PS in 40 patients with the TIPS insufficiency. After a mean follow-up period of 11.6 months, both the PS and the index shunt in the non-PS group behaved in a similar way regarding the cumulative primary shunt patency rates at 6, 12, 24, and 36 months (60.3%, 33.6%, 22.4%, and 7% vs. 65.1%, 46.1%, 18.5%, and 8.5%) [19].
It is noteworthy that following the previously mentioned studies, one publication of case series and limited case report studies were published [20,21,22]. Luo et al. reported the outcome of 18 patients with portal hypertension with PS insertion. All of the patients included in their study were cirrhotic except one patient complaining of Budd-Chiari syndrome. They used Wallgraft in 10 patients and Fluency stent in the remaining 8 patients. They reported that the creation of PS was technically successful in all patients. The PSG dropped significantly from 25.5 ± 7.3 mmHg to 10.9 ± 2.3 mmHg. The duration of follow-up was 16.7 ± 10.8 months. The primary shunt patency rates at 12 months after the creation of PS was 70% with Wallstent and 87.5% with Fluency endoprostheses [21].
In our study, median duration of patency was 16 months while the patency rates at 12 and 18 months were 86.4% and 77.7%, respectively. The patency rates of our series are higher than those mentioned in other comparable studies of the literature [18, 19, 21], although most of our patients (89.8%) were Budd-Chiari syndrome due with additional thrombophilic nature. We assume that this higher patency rate was attributed to many factors. The first factor is the use double anti-platelets and anti-coagulants given for all patients. Siegerstetter et al. reported a higher patency rate for the group using ticlopidine with heparin compared to heparin alone [23]. The second factor is the entry through the left PV or its neck. Either point of entry allows straight course of the stents with no apparent curves. This prevents turbulence of blood flow and subsequent thrombosis of kinks. Our findings agree well with those reported by Chu et al., Chen et al., and Luo et al. These authors reported higher patency rates for TIPS on the left compared to the right PV [24,25,26].
Regarding the complications, no death was recorded. Although we inevitably punctured the biliary duct with suspected hemobilia in 2 patients, there were no signs or symptoms of biliary obstruction. Bleeding occurred in 3 patients (8.1%) due to excessive trials to puncture the PV branches inside the liver. Other intra-procedure complications noted were respiratory distress and bradycardia that may be due to manipulation of the occluded stents with minor PE. It is noteworthy that the presence of the index stent in the liver tissue limits the manipulations of TIPS needle to target the PV. Liver function remained stable and no recorded encephalopathy or hepatocellular carcinomas.
Our study has some limitations. The first limitation is the short term follow-up with a mean follow-up of only 26.8 ± 8 months. The second one is the retrospective design of our study. The third limitation is the lack of a control group to compare the behavior of dysfunction between index and PS groups.