CTPV with complications of portal hypertension is a difficult clinical problem. For the treatment of thrombus itself, the anticoagulant effect is poor; for the treatment of portal hypertension complications caused by thrombus, the traditional methods such as drug and/or endoscopy are ineffective. Liver transplantation is difficult to perform15, 21, 22. PVR–TIPS offers new hope for the treatment of these patients. However, PVR–TIPS is a very difficult operation even for experienced surgeons, and the success rate is unlikely to reach 100%. The use of the collateral vein to establish a shunt is an alternative method when recanalization of the portal vein is not feasible, but its effectiveness is unclear. In this study, patients with refractory esophageal and/or gastric variceal bleeding caused by portal cavernous formation were selected from the prospective database of consecutive patients treated with TIPS in Xijing Hospital from January 2015 to May 2021. According to the method of TIPS, the patients were divided into the transcollateral TIPS group and the PVR–TIPS group. The efficacy and safety of these two methods of TIPS for CTPV with refractory variceal bleeding were analyzed. The results showed that transcollateral TIPS did not increase the risk of rebleeding, death, or operation-related complications. Furthermore, overt hepatic encephalopathy was significantly lower in the transcollateral TIPS group than in the PVR-TIPS group. These results concluded that transcollateral TIPS is a safe and effective treatment for portal cavernous formation with refractory variceal bleeding. All patients in the transcollateral TIPS group presented with recurrent variceal bleeding after endoscopic and medical treatment and received TIPS as salvage therapy. They were all treated with transcollateral TIPS when the portal vein could not be opened. To our knowledge, this is the first well-documented study of transcollateral TIPS.
This study confirmed that transcollateral TIPS was effective in the treatment of CTPV with recurrent variceal bleeding. We successfully treated CTPV with variceal bleeding using transcollateral TIPS15. Yamagami T et al. successfully treated a 65-year-old woman with recurrent variceal bleeding due to CTPV by using transcollateral TIPS, and no subsequent portal hypertensive bleeding occurred after transcollateral TIPS16. Brountzos EN et al. treated a 72-year-old patient with refractory portal hypertensive ascites due to CTPV by using transcollateral TIPS. The ascites disappeared after the operation, the stent was unobstructed, and no recurrence of ascites occurred during the follow-up period of 16 months17. However, Alexandra Wils reported 4 patients who were treated with transcollateral TIPS, 2 of which had good results, and 2 patients died within a short period after TIPS. One death occurred shortly after TIPS because of rebleeding of gastric varices. Another death was due to acute respiratory distress syndrome complicated by cardiac arrhythmias and bradycardia. The authors concluded that bleeding can be prevented for variceal veins communicating with collateral branches but not for variceal veins that do not communicate with collateral branches23. Another researcher used the method of transcollateral TIPS to treat a patient with recurrent variceal bleeding and CTPV. Variceal bleeding still occurred repeatedly after TIPS. The authors concluded that the pressure reduction of the portal system was not sufficient in patients with transcollateral TIPS, so rebleeding still occurred after the operation14. The reasons for the different results in those previous patients might be as follows: 1. the different condition of the collateral vessels used for the shunt; 2. the various relationship between the variceal veins and collateral vessels. If the collateral vessels had a larger diameter and were directly communicating with variceal veins, the PPG decreased more, and the risk of rebleeding was lower. Otherwise, it was the opposite. Therefore, we defined the collateral vessels used to establish portosystemic shunts for the first time, with a diameter of more than 6 mm and a straight vessel of more than 2 cm. The main reason was that the diameter of the TIPS stent used in the operation was 8 mm, and a 6–8 mm balloon was used to expand the stent after implantation. If the collateral vessels were less than 6 mm, the stent might not be sufficiently dilated, and the PPG might not be sufficiently decreased. In addition, there was a 2 cm bare area at the lower end of the TIPS stent, and a 2 cm straight blood vessel was required to conform to the stent bare area and that the fit was adequate. Furthermore, the vessels (usually the splenic vein) between the target collateral and the variceal veins should be opened if the collateral vessel do not directly communicate with the variceal veins. For these patients, it is not enough to establish a shunt using a collateral vessel. The blood from the varicose veins and their nourishing vessels does not directly flow into the shunt, and there is still local portal hypertension. Therefore, it is necessary to open the vessels between the varicose veins and the collateral vessels while establishing the shunt using the collateral vessels (Fig. 3). Because we defined the conditions for collateral vessels and opened the vessels between the collateral and varicose veins, the effect of collateral TIPS in preventing rebleeding was not different from that of PVR-TIPS.
This study also verified that transcollateral TIPS was safe. The collateral vessels of the cavernous transformation, unlike the portal vein, are not surrounded by the Glison sheath. They are often located outside the liver. Therefore, when using collateral vessels to perform TIPS, the operator is mostly worried about liver and collateral vessel injury leading to massive abdominal bleeding. Indeed, transcollateral TIPS is more difficult than conventional TIPS. One key point is that the number of punctures must be minimized. Second, when the external sheath of RUPS100 is delivered to the collateral vessels, the supporting force of the guide wire should be sufficient. If the hard guide wire is not deep enough, the external sheath of RUPS100 cannot be sent to the collateral vessels. At this time, other covered stents can be used instead of GOREVIATORR. Therefore, although the transcollateral TIPS technique is harder, for experienced experts, transcollateral TIPS does not increase operation-related complications compared with PVR-TIPS. In our study, the number of operation-related complications and overall survival of transcollateral TIPS were comparable to those of PVR–TIPS. Furthermore, our study found that the incidence of hepatic encephalopathy in the transcollateral TIPS group was significantly lower than that in the PVR-TIPS group. This may be because the blood of the portal vein was often completely shunted in the PVR-TIPS group but was only partly shunted in the transcollateral TIPS group. There may be other collateral veins to supply blood to the liver in transcollateral TIPS. In summary, the results of this study preliminarily confirmed that transcollateral TIPS is safe and effective in the treatment of CTPV with recurrent variceal bleeding.
This study had the following limitations. First, this was a retrospective study. Second, all patients chose transcollateral TIPS when the portal vein could not be opened rather than both PVR–TIPS and transcollateral TIPS. Therefore, this study has some bias. That is, the degree of PVT in patients with collateral TIPS is more severe than that in patients with PVR-TIPS. Third, the sample size of transcollateral TIPS was small.
In conclusion, our study suggests that transcollateral TIPS is a safe and effective alternative for patients with CTPV and recurrent variceal bleeding who have difficulty implementing PVR–TIPS. At the same time, in this study, we preliminarily proposed the technical standard of transcollateral TIPS, namely, the diameter of the collateral is greater than 6 mm, and the straight length of the collateral is more than 2 cm. Moreover, the vessels that give off the variceal veins should be opened to directly communicate with the collateral vessels.