Percutaneous Mesocaval Shunts

Chapter 25: Percutaneous Mesocaval Shunts

Robert K. Kerlan Jr., Sue J. Rhee, and Jeanne M. LaBerge

Introduction

Transjugular intrahepatic portosystemic shunts (TIPS) have replaced surgical shunting as the preferred method to manage symptomatic complications related to portal hypertension that fail conservative treatment. Unfortunately, not all patients are candidates for conventional TIPS creation.

One situation that makes the creation of TIPS difficult is the presence of chronic portal vein (PV) thrombosis ( Fig. 25.1). Although recanalization of the PV can be achieved in up to 80% of individuals, in some cases it is not possible. In patients in whom it is not possible, a surgical shunt may be used as an alternative. Unfortunately, patients with advanced liver disease have significant operative morbidity and mortality related to the operation.

An innovative alternative to the open surgical shunt, the percutaneous mesocaval shunt, was originally described by Nyman et al.¹ In this procedure, a direct communication is created between the superior mesenteric vein (SMV) and the inferior vena cava (IVC). This chapter will describe the technique of creating a percutaneous mesocaval shunt.

Indications and Contraindications

• Bleeding in patients with chronic PV occlusion

• Intractable ascites in patients with chronic PV occlusion

• Failed percutaneous transhepatic PV reconstruction

• Poor surgical candidate

• Failed surgical shunt

Fig. 25.1 Venous phase of superior mesenteric arteriogram reveals occlusion of the extrahepatic portal vein and numerous varices.

Technique

There are two methods to perform a percutaneous mesocaval shunt: (1) a combined transabdominal and transvenous approach and (2) an exclusively transvenous approach.

Combined Transabdominal and Transvenous Approach

The first method uses a combined percutaneous and transvenous approach.1 The procedure is reasonably entailed and should be performed under general anesthesia. Prophylactic antibiotics should be administered.

The patient is placed supine on the computed tomography (CT) table. Survey images are obtained to delineate a safe route that extends through the SMV into the IVC. As a 22-gauge needle will be used to puncture, transgression through liver and bowel is acceptable. Routes extending through the pancreatic parenchyma or duodenum insinuated between the IVC and SVC are not acceptable and should be avoided.

A skin site is selected, and the area is sterilely prepped and draped. A 22-gauge 15- or 20-cm-length needle is then advanced with CT guidance from the anterior abdominal wall through the SMV and into the IVC ( Fig. 25.2). Blood is aspirated through the needle to confirm an intravascular position. Subsequently, a 260–cm, 0.014-in diameter guidewire is advanced through the needle into the IVC. Wire position is confirmed with CT scanning.

Fig. 25.2 A 22-gauge needle (arrow) is advanced from the anterior abdominal wall through the superior mesenteric vein into the inferior vena cava.

Fig. 25.3 A 0.018-in guidewire is snared in the inferior vena cava from a jugular approach.

The patient is subsequently transferred under general anesthesia to the fluoroscopic suite, where the skin overlying the right internal jugular vein is sterilely prepped and draped. Ultrasound-guided access to the right internal jugular vein is established, and a 10-Fr sheath is placed. An Amplatz goose-neck or other snare is used to capture the free end of the 0.014-in guidewire ( Fig. 25.3) and pull it externally through the 10-Fr angled sheath and out the neck. Of note, the 0.014-in guidewire needs to be advanced through the indwelling 22-gauge needle while the free end of the wire is being pulled.

Next, a low-profile 3.5- or 4-Fr, 5-mm-diameter, 2-cm-length angioplasty balloon catheter is advanced over the 0.014-in guidewire. The transabdominal 22-gauge needle is retracted to a position proximal to its ventral entry into the SMV. The angioplasty balloon is inflated across the tract extending from the IVC to the SMV. As the SMV cannot be seen, its position must be estimated.

The balloon catheter is then removed and replaced with a 4-Fr angled catheter. A side-arm adaptor is placed on the 4-Fr catheter allowing injection of contrast through the catheter to assess the position of the catheter tip. This catheter is advanced over the 0.014-in wire through the 10-Fr sheath across the IVC wall into the anticipated position of the SMV. A small amount of contrast is injected accompanied by gentle manipulation until the catheter tip is securely within the SMV ( Fig. 25.4).