Transjugular Intrahepatic Portosystemic Shunts

Cirrhosis and its complications are common throughout the world. Hepatitis B and C and alcohol abuse account for about 90% of cases. Risk of death comes from variceal bleeding, progressive liver failure, and hepatoma. Key quality-of-life issues include management of ascites and hepatic encephalopathy.

Transjugular intrahepatic portosystemic shunt (TIPS) is one of the treatments available to control variceal bleeding and ascites by correction of portal hypertension.

Esophageal varices are most common, occurring in 40% of cirrhotic patients at diagnosis and increasing by 6% per year. Gastric varices are seen in 20% of patients. Ectopic varices are less common. Sites include duodenum, jejunum, lienorenal, rectal, and parastomal varices.

In patients with varices, the risk of a first hemorrhage is around 4% per year. Risk factors include size of varices, Child-Pugh class B or C, and hepatic vein pressure gradient greater than 12 mm Hg. Esophageal varices account for 70% of bleeding. Mortality within 6 weeks of bleeding is about 30%. It is most often related to uncontrolled bleeding or early rebleeding. Other causes include liver failure, multiorgan failure, and sepsis. Without preventive treatment, rebleeding occurs within 2 years in up to 65% of patients, and mortality from rebleeding is 33%.

Ascites in patients with cirrhosis and portal hypertension results from:

1.
Elevated venous pressure in the gut causing fluid transudate into the peritoneal cavity.
2.
Elevated sinusoidal pressure causing transudate from the liver surface.
3.
Renal effects of cirrhosis resulting in sodium and water retention.
4.
Reduced albumin contributing to extravascular fluid retention.

Ascites causes significant impairment of quality of life. Frequent percutaneous drainage procedures may be required. Complications include spontaneous bacterial peritonitis and hepatorenal syndrome. TIPS is most effective in treatment of ascites when the hepatic vein pressure gradient is high.

Treatment of Portal Hypertension

Measures for prevention and treatment of variceal bleeding include endoscopic, interventional, and drug treatments. Endoscopic treatment includes sclerosant injection, band ligation, and cyanoacrylate injection of varices. Interventional treatments include TIPS, transhepatic embolization, balloon-occluded retrograde transvenous obliteration, and partial splenic embolization.

Drugs that reduce portal pressure include the vasoconstrictor drugs terlipressin and octreotide in acute therapy and propranolol for long-term control. These agents reduce splanchnic blood flow. The vasodilators glyceryl trinitrate and isosorbide mononitrate reduce resistance at the hepatic sinusoidal level.

Indications

Variceal Hemorrhage

For gastric and esophageal varices emergency TIPS is indicated when endoscopic therapy fails. For bleeding ectopic varices it can be used as first-line therapy. Outcomes are best when TIPS is performed early, ideally within 24 hours of presentation.

TIPS is also used for prevention of rebleeding. Even with preventive medical therapy, rebleeding after endoscopic treatment occurs in 25% to 33% of patients over 18 months. A randomized controlled trial identified patients with high risk of rebleed and compared the outcome of endoscopic banding plus TIPS with banding alone. The study demonstrated a marked reduction in rebleeding and improved patient survival at 1 year. The authors identified the timing of TIPS within 72 hours of endoscopy as a critical factor in producing an improved clinical outcome.

Gastric varices have a greater tendency to rebleed acutely after successful TIPS. Rebleeding can occur despite reducing the portal systemic pressure gradient to less than 12 mm Hg. For this reason, transvenous embolization and sclerosis of varices should be performed routinely during TIPS for bleeding gastric varices.

Ascites

Transjugular intrahepatic portosystemic shunting is effective in reducing ascites in patients with portal hypertension. Benefits include symptomatic control and reduced risk of hepatorenal syndrome and spontaneous bacterial peritonitis. However, its role is limited by the risk of encephalopathy and progressive liver failure. Results of trials and meta-analyses are mixed when assessing benefits to survival and quality of life. Improvement in control of ascites can be expected in approximately two-thirds of patients. New or worsened encephalopathy is seen in 32%. This can usually be controlled with medication but may require a shunt-reducing stent or shunt occlusion. Six-month mortality is around 36%. Poor outcome is more likely in those with a bilirubin level over 3 mg/dL, creatinine level over 1.5 mg/dL, and age older than 60 years. Improved ascites control is more likely in those with a higher portosystemic pressure gradient (mean 21 mm Hg vs. 15 mm Hg).

TIPS is generally considered to be indicated only in those patients with large-volume ascites that cannot be controlled with medical therapy and requires repeated large-volume paracentesis at less than monthly intervals.

Hepatic hydrothorax, in which ascitic fluid passes through defects in the diaphragm, is similar to ascites in its pathophysiology and responds to TIPS in a similar way.

Budd-Chiari Syndrome

Interventional procedures appear to be important in treating Budd-Chiari syndrome (BCS). Presentation is most commonly with subacute disease causing ascites and tender hepatomegaly. Less common is fulminant hepatic failure or end-stage chronic liver disease. Patients with well-compensated disease, particularly where not all hepatic veins are involved, typically have a good long-term prognosis.

Treatment is indicated in patients who are symptomatic or have abnormal liver function tests, suggesting ongoing damage to hepatocytes. Treatments can include thrombolysis, angioplasty, and stenting of hepatic veins. These may be successful at controlling symptoms in the short term, but recurrence is common. If these treatments fail or are not appropriate, TIPS can be used to provide an alternative venous outflow path for the liver. TIPS provides good symptomatic control and improved liver function in both fulminant and subacute BCS. BCS patients have an increased risk of shunt stenosis and thrombosis. Regular long-term follow-up is critical because restenosis is associated with progressive liver damage.

Although no randomized studies have been performed, patients treated with TIPS have a good long-term survival compared with historical series and predicted survival based on biochemical and clinical parameters at presentation. ^, ^, ^, Control of symptoms and prevention of disease progression means these patients can delay or avoid the need for liver transplantation.

Alternatives to Transjugular Intrahepatic Portosystemic Shunt

The direct intrahepatic portosystemic shunt extends from the intrahepatic inferior vena cava (IVC) through a short parenchymal track in the caudate lobe of the liver into the portal vein and may be suitable in some anatomic situations. Stented to 8 mm with a covered balloon-expandable stent, it provides a short low-resistance shunt with minimal liver trauma and low risk of restenosis.

In patients with predicted poor outcome from TIPS, bleeding can be controlled using alternative interventional techniques, either balloon-occluded retrograde transvenous obliteration or transhepatic transportal injection of sclerosant, with or without coil embolization. Published results suggest these techniques may result in improved survival with lower rates of encephalopathy and rebleeding.

Contraindications

Relative contraindications to TIPS include:

Cardiac failure, elevated right-sided heart pressure, and pulmonary hypertension
Rapidly progressive liver failure
Severe uncorrectable coagulopathy
Sepsis
Biliary obstruction
Malignancy
Encephalopathy

Polycystic liver disease has previously been considered a contraindication, but TIPS has been performed safely in these patients. Coagulopathy, shock, and sepsis are relative contraindications, but it may still be appropriate to perform an urgent TIPS procedure while these are being corrected.

A number of anatomic features may make TIPS difficult or impossible. These include absence of the portal vein and distortion of venous anatomy due to liver atrophy. Modified TIPS techniques may be effective in these patients. More recent data suggests that portal vein recanalization can be successfully combined with TIPS.

Other relative contraindications are predictors of poor prognosis after TIPS. The most accurate prediction of post-TIPS mortality is the Model for End-Stage Liver Disease (MELD) score. The scoring system was developed specifically for use in prediction of post-TIPS outcome.

\begin{matrix} 9.6 \times \log e (Creatinine [\frac{mg}{dL}]) \\ + 3.8 \times \log e (Bilirubin \frac{mg}{dL}) + 11.2 \times \log e (INR) \\ + 6.4 \times (etiology: 0 ifalcoholicorcholestatic, 1 otherwise) \end{matrix}

$\begin{matrix} 9.6 \times \log e (Creatinine [\frac{mg}{dL}]) \\ + 3.8 \times \log e (Bilirubin \frac{mg}{dL}) + 11.2 \times \log e (INR) \\ + 6.4 \times (etiology: 0 ifalcoholicorcholestatic, 1 otherwise) \end{matrix}$

A 30-day mortality of 3.7% (1 in 27) is reported for patients with a MELD score of 1 to 10. Mortality increases to 60% (3 in 5) with a MELD score above 24.

The Child-Pugh score has similar predictive effect on patient outcome after TIPS but may be slightly less accurate. The simplest prognostic measure is the serum bilirubin value alone. A bilirubin value over 3 mg/dL is associated with an increase in 30-day mortality after TIPS.

Equipment

Equipment required is listed in Table 78.1 . Invasive pressure-measuring equipment, appropriate patient-monitoring facilities, and high-quality digital subtraction angiographic imaging are essential ( ). Ultrasound is also useful.

TABLE 78.1

Disposable Equipment for Use in Transjugular Intrahepatic Portosystemic Shunt Treatment

TIPS Set

40-cm long, 10F sheath
10F angled introducer with metal stiffener
47-cm, 5F straight catheter with central sharp 0.035-inch trocar wire

Angioplasty Balloons

Predilation balloon: 8 × 40 mm
Postdilation balloons: 10 × 40 mm, 12 × 40 mm

Guidewires

Amplatz Extra Stiff: 0.035 inch, 260 cm
Angled Glidewire: 0.035 inch, 150 cm
Bentson wire: 0.035 inch, 145 cm

Catheters

5F Davis T, 65 cm
5F multipurpose, 65 cm
5F Cobra, 65 cm

Stents

VIATORR. Covered lengths 5 to 8 cm, diameter 10 mm (8 mm and 12 mm also available)

Micropuncture Set

22-gauge Chiba needle
0.021-inch platinum-tipped Mandril wire

Invasive Pressure-Measuring Transducer

TIPS , Transjugular intrahepatic portosystemic shunt.

Video 78.1 Plane digital subtraction angiography demonstrating balloon inflation within the right portal vein as an angiographic target for traversing the hepatic parenchyma from the right hepatic vein. (Courtesy Mark Duncan Brooks and Julian Maingard.)

Video 78.2 Plane digital subtraction angiography demonstrating balloon inflation within the right portal vein as an angiographic target for traversing the hepatic parenchyma from the right hepatic vein. (Courtesy Mark Duncan Brooks and Julian Maingard.)

The TIPS set we use is the Cook Rösch-Uchida transjugular liver access set (RUPS) (Cook Medical, Bloomington, IN). It includes a long 10F sheath, a 10F angle-tipped steel-reinforced cannula, and a 5F catheter with a central pointed trocar. In this set, the steel-reinforced cannula is positioned in the hepatic vein and directed toward the portal vein. Then the 5F catheter/trocar combination is advanced through the liver parenchyma into the portal vein.

Our preferred TIPS stent is the VIATORR (W.L. Gore & Associates, Flagstaff, AZ). This is a purpose-designed covered TIPS endoprosthesis made from Nitinol and expanded polytetrafluoroethylene. Its inner surface is identical to standard vascular grafts, whereas an outer less porous layer is designed to withstand bile intrusion into the lumen. The graft is supported by a Nitinol wire skeleton. At its portal end is a highly flexible uncovered segment of Nitinol stent that anchors the device in the portal vein without occluding portal flow.

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