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296 Chew and Conte
36. Snady H. The role of sclerotherapy in the treatment of esophageal varices: personal experience and a
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37. Rikkers LF, Jin G, Burnett DA, et al. Shunt surgery versus endoscopic sclerotherapy for variceal
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38. Sanyal AJ, Freedman AM, Luketic VA, et al. The natural history of portal hypertension after
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39. Rosemurgy AS, Goode SE, Zwiebel BR, et al. A prospective trial of transjugular intrahepatic
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Chapter 25 / TIPS 297
25 Transjuglar Intrahepatic
Portosystemic Shunt
Grant J. Price, MD
CONTENTS
INTRODUCTION
INDICATIONS
CONTRAINDICATIONS
TECHNIQUE
ADVANCED TECHNIQUES
PREOPERATIVE TESTING AND PREPARATION
COMPLICATIONS
RESULTS
POSTOPERATIVE CARE
ALTERNATIVES
COST
SUMMARY
REFERENCES
INTRODUCTION
Portal venous hypertension is a common end point of most chronic diseases of the
liver. Portal hypertension can be caused less frequently by obstruction of the main portal
vein by thrombus or tumor or by obstruction of hepatic venous outflow from the liver
(Budd-Chiari syndrome). However, most cases of portal hypertension seen in internal
medicine practices are caused by alcoholic cirrhosis or advanced chronic viral hepatitis.
The most common deadly consequence of severe portal hypertension is bleeding from
varices of the esophagus and stomach, but other sequelae such as intractable ascites are
common and difficult to treat medically.
The transjugular intrahepatic portosystemic shunt (TIPS) procedure is a percutaneous
method for decompression of the portal venous system (1). The TIPS consists of a stented
tract placed inside the liver between the portal venous system and the systemic venous
circulation, usually between the right portal vein and the right hepatic vein. This shunt
allows flow of blood around the diseased liver, effectively lowering the portal pressure
and alleviating many of the sequelae of portal hypertension. In the 10 yr since the
From: Clinical Gastroenterology: An Internist's Illustrated Guide to Gastrointestinal Surgery
Edited by: George Y. Wu, Khalid Aziz, and Giles F. Whalen © Humana Press Inc., Totowa, NJ
297
298 Price
introduction of the TIPS procedure, it has virtually replaced surgical portosystemic
shunts in most centers.
In the United States, TIPS is performed almost exclusively by interventional radiologists. Procedures are almost always done within a radiology department. Required
equipment consists of an angiography table with digital subtraction capabilities, a
selection of standard catheters, guidewires, balloon catheters and stents, a physician
qualified to perform the procedure, and an intensive care unit appropriate for the preand postoperative care of these often quite ill patients. Although the procedure is
offered at essentially all University and tertiary centers, it is also quite commonly done
in community hospitals. (This author has been performing TIPS in a community hospital since early 1992). Case volumes have exploded nationally; and are currently in
the many thousands per year.
Elective TIPS on stable patients can usually be performed on a one-night admission, although longer stays can sometimes be necessary. Outpatient procedures can
be done on occasion, although in the author’s experience this has usually involved a
semicompliant patient who refused to stay overnight. Emergency TIPS on acutely
bleeding patients will involve a longer stay due to the poor overall condition of most
such individuals.
INDICATIONS
Treatment and Prevention of Variceal Bleeding
This is by far the most common indication for the TIPS procedure. Timing of TIPS
for this indication is somewhat controversial, depending on overall condition of the
patient, candidacy for liver transplant, and institutional availability of alternative methods for treating variceal bleeding. However, it is important to remember that while TIPS
can be performed with good results on very ill and unstable patients who are actively
bleeding, there is a very large difference in outcomes of emergency vs elective TIPS.
Consequently, most interventional radiologists would advocate creation of the TIPS
before the catastrophic bleed or after the patient has been stabilized following a bleed.
In the author’s center, for instance, the 30-d mortality of patients brought for elective
TIPS done for prevention of variceal bleeds is zero, whereas the 30-d mortality of
patients receiving TIPS while hypotensive, intubated, and actively bleeding approaches
50%. All of this being said, TIPS is a highly effective treatment for variceal bleeding.
Rebleeds occur in 4–17%, and most of these occur in patients whose shunts have
become compromised (2,3).
Intractable Ascites
TIPS is a very effective therapy for intractable ascites as a result of portal hypertension, and leads to improvement or resolution in most patients. However, shunting is
indicated only when medical management fails. One should keep in mind that patients
undergoing TIPS for this indication are almost always in the very late stages of their liver
disease. TIPS has an unpredictable effect on liver function in such patients, and can lead
to accelerated encephalopathy or frank liver failure. Conversely, liver function can
paradoxically improve.
Chapter 25 / TIPS 299
Intractable Pleural Effusions
There is considerably less data for this indication. However, on the basis of the
available experience, it would seem that effectiveness of shunt for pleural effusions is
similar to that for ascites. Again, these patients are often fragile with tenuous liver
function, and TIPS should be done only when medical management fails.
Hepatorenal Syndrome
The literature consists mainly of case reports with variable but generally positive
outcomes. Given the generally poor outcomes experienced with conservative management of these patients, TIPS should be considered for any otherwise salvageable patient
suffering from hepatorenal syndrome.
Budd-Chiari Syndrome
In the very earliest going, Budd-Chiari syndrome was considered a relative contraindication to TIPS because of the concomitant restricted access to the hepatic veins. However, as techniques have improved, TIPS has become a primary mode of therapy for
portal hypertension related to Budd-Chiari (see “Advanced Techniques”) (4).
As a Bridge to Transplantation
Because it does not disturb native anatomy, TIPS is greatly preferable to surgical
shunt in patients who are candidates for liver transplants and need portal decompression
for any of the above reasons. Care is taken in these patients not to extend the stents any
farther into the main portal vein than absolutely necessary (5).
CONTRAINDICATIONS
Right heart failure is an absolute contraindication to TIPS, as these patients respond
badly to arrival of high-volume portal venous flow directly into their compromised right
hearts. Fatal cases of congestive heart failure have occurred. Severe hepatic encephalopathy or liver failure is a relative contraindication to TIPS, as the shunt decreases intrahepatic portal venous flow in most patients, potentially diminishing already compromised
function. That being said, TIPS is often performed in this patient population on a “nothing
to lose” basis, as it is sometimes the only available therapy for a severely encephalopathic
patient who is also bleeding. Whereas untreatable encephalopathy, liver failure, and death
sometimes do result, many patients do surprisingly well, and seemingly unsalvageable
patients can sometimes be salvaged. Severe coagulopathy caused by liver dysfunction is
unfortunately common in this patient population, but is only a relative contraindication
to TIPS. The procedure can be performed safely in patients with coagulopathy or thrombocytopenia by careful attention to technique; capsular punctures are to be avoided.
Patients who are in DIC at the time of shunt rarely do well. Cavernous transformation of
the portal vein can preclude TIPS, but can sometimes be overcome by transhepatic access
into an intrahepatic portal vein branch followed by recanalization of the main portal vein
via PTA and stent. Although most patients with cavernous transformation are well enough
collateralized to avoid sequelae of portal hypertension; those needing shunt should be
referred to an experienced operator.
300 Price
Fig. 1. Portal and hepatic venous anatomy.
TECHNIQUE
The following is a basic step-by step description of the procedure. All moves are made
with fluoroscopic guidance. The reader may find the illustrations helpful in visualizing
the below (Fig. 1) shows the relevant anatomy (6,7).
1. The right internal jugular vein is accessed percutaneously, and a large-bore vascular
sheath is advanced through the right atrium into the upper inferior vena cava (IVC).
2. The right hepatic vein is accessed with a steerable angiographic catheter, and a hepatic
venogram performed (Fig. 2).
3. The catheter is advanced peripherally in the hepatic vein, and a wedged venogram performed in an attempt to opacify the portal venous system. Some operators use CO
this. Some experienced operators (including this author) omit this step (Fig. 3).
4. The sheath is advanced into the hepatic vein. A long, curved cutting needle is advanced
over a guidewire inside the sheath until its tip rests in the hepatic vein.
5. The guidewire is removed, the needle tip is unsheathed, and the needle advanced into the
hepatic parenchyma. Passes are made until the needle tip finds an intrahepatic branch of
the portal vein. Care is taken not to pass the needle through the liver capsule. Great care
is also taken that the hepatic venous and portal venous ends of the final needle position
are both intrahepatic. Finding a usable needle position in the portal tree is generally the
most difficult step in the procedure.
6. A guidewire is passed through the needle into the main portal vein, creating a connection
between the hepatic vein and the portal vein. A wire or catheter is left in place through
this tract from now until the end of the procedure (Fig. 4).
7. Pressures are measured in the main portal vein and in the upper inferior vena cava in order
to establish the baseline portosystemic gradient. A portogram is then performed to outline
the portal system for shunt, and to identify any high-flow varices that are present. Any
important stenoses or occlusions in the portal system are also identified and corrected.
2
for
Chapter 25 / TIPS 301
Fig. 2. Catheterization of the hepatic vein.
8. An angioplasty balloon is positioned across the intrahepatic tract and inflated to expand
the tract to usable size.
9. A metallic vascular stent is placed across the newly created tract. Most available stent
designs have been successfully used (Fig. 5) (8).
10. A second portogram is obtained to evaluate the morphology of the newly created shunt
and any changes in the flow pattern of the portal system (Fig. 6). Additional stents are
placed if needed.
11. Pressure measurements are obtained in the portal vein and IVC. The gradient between
them should be no more than 10–12 mmHg at this point. If the gradient is significantly
higher than 10–12 mmHg, the shunt is expanded with a larger balloon, or a second
“parallel” TIPS is created.
12. Once acceptable hemodynamic result is achieved, the sheath is exchanged for a large bore
catheter which is left in place at SVC or right atrial level until the patient is stable and
follow-up Doppler confirms shunt patency.
ADVANCED TECHNIQUES
TIPS have been successfully created through occluded hepatic veins, thrombosed
portal veins, and tumor-occluded portal veins. Techniques for accessing difficult portal
anatomy have included shunt into left, middle, or caudate portal veins, portal access via
transhepatic or transsplenic punctures, minilaparotomy allowing portal access via
jejunal veins, and portal access through enlarged umbilical veins (9). Techniques to
avoid difficult hepatic venous anatomy include use of the left and middle hepatic veins,
302 Price
Fig. 3. Wedged hepatic venous portagram.
shunt directly to the intrahepatic IVC, stent of stenotic or occluded hepatic veins, and
transhepatic access to intrahepatic branches of the hepatic vein. Techniques to overcome absence of the right internal jugular vein include access from the right external
jugular vein, left internal jugular vein, and right common femoral vein, as well as
transhepatic punctures (9).
It is fair to say that the only limitations are in the imagination and experience of the
interventionalist seeing the patient, and that no patient needing a shunt should be excluded
a priori for reasons of anatomy. Rather, patients presenting with anatomic challenges
should be counseled regarding lower chance of technical success, and should be sent to
an interventional radiologist who is very experienced in the procedure. Overshunted
patients can be salvaged by the creation of a reducing stent, which is placed into the TIPS
to reduce, but not occlude its flow. Varices showing high-grade hepatofugal flow after
hemodynamically successful shunt creation can be catheterized via the TIPS and
embolized with metallic coils. It is important to remeasure the portosystemic gradients
after embolization because closing a high flow varix cuts off a high-flow exit from the
portal system and can raise portal pressure (9).
Covered stents are a new and potentially revolutionary development. The available
designs consist of conventional metallic stents covered with PTFE or other biocompatible
material. The covering excludes the shunted blood from the surrounding hepatic envi-
Chapter 25 / TIPS 303
Fig. 4. Catheterization of the portal vein.
ronment. Available data suggest that this has a major positive effect in reducing the
incidence of stenosis and occlusion of the shunts. Original studies were done with homemade devices constructed of standard stents sewn to PTFE bypass material. Commercially manufactured covered stents have been available in Europe since the mid-1990s,
and are recently available in the United States. A device developed specifically for TIPS
is in the late stages of commercial development.
PREOPERATIVE TESTING AND PREPARATION
In the elective or reasonably stable patient, preoperative testing is desirable for
planning the approach to the shunt and alerting to the risk of preventable complications. Keep in mind that patients requiring emergency TIPS for catastrophic bleeds
may not have time for any preoperative imaging at all. Imaging is focused on the
evaluation of patency of the portal vein and hepatic veins and in planning approach to
the more challenging patients. Doppler ultrasound is the easiest and least invasive way
to do this, although CT, MRI, and angiography have all been used. CT scanning can
be useful for understanding the morphology of the liver. Keep in mind that in advanced
304 Price
Fig. 5. Completed TIPS.
cirrhotics, atrophy of the right lobe, hypertrophy of the left lobe, and hypertrophy of
the caudate lobe are all common, and can require alteration of the plan of attack.
Endoscopy is very desirable preoperatively in cases done for upper gastrointestinal
bleeding. Although common, varices are not the only possible reason for upper gastrointestinal bleeding in alcoholic patients. TIPS has no beneficial effect on common
nonvariceal causes of bleeding such as Mallory-Weiss tears or gastritis. Blood tests
include LFTs, BUN, and Creatinine determination, PT/PTT, hemoglobin, hematocrit,
and platelet count. Hydration of the patient is desirable, particularly in those with any
degree of renal insufficiency. Radiographic contrast presents a special risk to those
patients. Prophylactic antibiotics are generally given to patients preoperatively. Many
regimens exist. Correction of coagulapathy is sometimes desirable, but fairly controversial. So many of these patients have baseline coagulopathies that many operators
treat only severe coagulopathy (PT>20, plts<50,000). Meticulous technique and avoidance of capsular puncture are probably more important than medical pretreatment in
coagulopathic individuals. Renoprotective drugs are a new, but promising preoperative treatment for patients with renal insufficiency. Mucomyst and Fenaldopam are the
most promising. Paracentesis is usually not necessary, but in extreme cases ascites will
degrade the fluoroscopy image or distort the liver orientation enough to require preoperative drainage. Keep in mind that high volume paracentesis followed by TIPS
creation adds up to significant hemodynamic alteration over a short period of time, and
obligates careful monitoring of the state of hydration of the patients, particularly in
those who also have GI bleeding.
Chapter 25 / TIPS 305
Fig. 6. Portagram following TIPS.
COMPLICATIONS
Transient hepatic encephalopathy is fairly common. Typical reported rates are in the
10–15% range, although much higher rates have been reported in a few series. Whereas
most cases can be successfully treated with lactulose, a very few severe instances require
shunt revision or closure. Intraperitoneal bleed can result from inadvertent puncture of
the liver capsule by the needle. Symptomatic cases are rare (1%) in experienced hands.
Delayed shunt stenosis and occlusion is discussed later under “Results.” Acute fulminant hepatic failure is a rare occurrence, and can be related to inadvertent connection of
a hepatic arterial branch to the shunt. It can be diagnosed and treated by hepatic arteriography and coil embolization of the offending branch. Hemobilia is a rare complication
and is seen in about 1% of cases. Transient renal failure is related to contrast nephrotoxicity and hepatorenal syndrome. It occurs in about 3% of cases. Bacteremia is seen in
about 3% of cases.
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