Pre-stressed rack of intrahepatic portacaval shunt

Abstract

The pre-stressed rack of intrahepatic portal vein bypass includes main rack and auxiliary rack connected via Ni-Ti alloy wire in 40-90deg angle, and both the main rack and the auxiliary rack are nets woven with Ni-Ti alloy wires. The main rack has the end far from the auxiliary rack in radial shape, the pre-stressed rack is a coated one and has diameter of 8-10 mm, and the main rack and the auxiliary rack has length of 3-5cm and 1.5cm separately. Under the action of pre-stress, the pre-stressed rack has its main rack, auxiliary rack and ''hat brim'' contact closely with the left branch, the right branch and the lower liver section cavity wall of the portal vein separately. The present invention has structure coincide the anatomical relation of the intrahepatic portal vein and is significant in further perfection of PTPS.

Description

technical field [0001] The invention relates to medical equipment, in particular to a prestressed support for intrahepatic portal vein shunt. Background technique [0002] Intrahepatic portocaval shunt is a minimally invasive treatment technique using interventional equipment under the monitoring of an imaging system. So far, there are two ways to establish portocaval shunt using this minimally invasive method: one is through the neck The second is through the femoral vein. The former is an important choice for the clinical treatment of complications related to cirrhosis and portal hypertension, and the latter is extremely rare (only 1 case). However, in clinical practice, the right internal jugular vein of the patient was stenotic or occluded It is not uncommon, accounting for about 5.6%. It often causes difficulties in the operation of transjugular intrahepatic portocaval shunt (TIPS). However, the left internal jugular vein has a tortuous path and is closer to the aortic ...

AI Technical Summary

Problems solved by technology

[0002] Intrahepatic portocaval shunt is a minimally invasive treatment technique using interventional equipment under the monitoring of an imaging system. So far, there are two ways to establish portocaval shunt using this minimally invasive method: one is through the neck The second is through the femoral vein. The former is an important choice for the clinical treatment of complications related to cirrhosis and portal hypertension, and the latter is extremely rare (only 1 case). However, in clinical practice, the right internal jugular vein of the patient was stenotic or occluded It is not uncommon, accounting for about 5.6%. It often causes difficulties in the operation of transjugular intrahepatic portocaval shunt (TIPS). However, the left internal jugular vein has a tortuous path and is closer to the aortic arch, which may accidentally injure the aorta. The potential danger of arteries and brachiocephalic arteries restricts the interventional therapy for patients with portal hypertension; on the other hand, in addition to the problem of access, TIPS also has the risk of a hard 10F puncture trocar passing through the right atrium, which is difficult for patients with a large number of Patients with pleural and ascites are more likely to accidentally injure the right atrium and cause complications of cardiac tamponade

[0003] In order to solve the above problems, one-step percutaneous transhepatic portocaval shunt (PTPS) came into being, that is, direct percutaneous transhepatic puncture from the portal vein branch to the inferior vena cava of the liver segment to establish portocaval shunt, reduce the portal vein pressure, and achieve the treatment of portal hypertension. For the purpose of related complications, however, the PTPS in the relevant case reports is only a percutaneous transhepatic combined with a transjugular vein method for TIPS operation. The internal vein is taken out, and then the balloon dilation and stent release are completed through the jugular vein. The essence still belongs to the technical category of traditional TIPS, which not only increases the trauma of the patient, but also increases the difficulty of the operation. At the same time, if the percutaneous transhepatic Portocaval shunt (PTPS) still uses the traditional straight barrel stent, and two difficult situations may occur: (1) The portal vein end of the stent will be thrown into the right branch of the portal vein, not only cannot form a shunt to reduce the portal vein pressure, It will also cause the main blood flow of the portal vein to perfuse into the liver, causing liver failure over time

In addition, the blood flow in the main portal vein will be fully mixed, and the meaning of left portal vein shunt will be lost. (2) Due to the limitation of PTPS approach and surgical method, the release of the stent can only be done by first releasing the inferior vena cava end of the hepatic segment, Finally, the portal vein end is completely released. The use of straight tube-shaped traditional stents in PTPS cannot accurately predict the reserved length of the portal vein end stent. It is possible that the stent fails to bridge the two veins of the shunt, causing the shunt to occlude early and fail.

[0004] In short, it is difficult to realize the relationship between the two ends of the stent implanted in the traditional shunt and the walls of the two veins to achieve an intravascular shape similar to surgical side-to-side anastomosis.

Images