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American
Association for the Study of Liver Diseases 50th
Annual Meeting
Portal Hypertensive Bleeding
Steven K. Herrine, MD
Background
Bleeding from esophageal varices
occurs in approximately 30% of patients with chronic
liver disease and portal hypertension.
Gastrointestinal bleeding due to portal hypertension
is estimated to cost approximately $1.2 billion per
year in the US.[1]
Nonselective
beta-blockade with propranolol or nadolol has been
shown in meta-analyses to decrease the risk of first
variceal hemorrhage in those patients with high-risk
varices.[2]
Despite advances in endoscopic and pharmacological
approaches to treatment and prevention of variceal
hemorrhage, mortality of a first-time bleed remains in
excess of 30%. Among pharmacological agents available
in the US, octreotide has the most favorable profile
in acute variceal hemorrhage.[3]
In recent years, endoscopic variceal band ligation (EVL)
has emerged as the therapy of choice for variceal
hemorrhage over endoscopic injection sclerotherapy,
yielding similar efficacy rates with fewer
complications.[4]
Combination sclerotherapy and band ligation does not
appear to improve patient outcome.[5]
Results of randomized trials have discouraged the use
of sclerotherapy as prophylaxis against index bleed in
patients with high-risk varices.[6]
The use of prophylactic band ligation to prevent first
variceal bleed remains under investigation.[7]
In bleeding that persists despite medical and
endoscopic intervention, portal decompression by way
of TIPS (transvenous intrahepatic portosystemic shunt)
has proven effective.[8]
In selected cases, surgical shunts or esophageal
transection is useful in the control of variceal
hemorrhage.[9,10]
Leon
Schiff Lecture
Dr. Roberto Groszmann elegantly
painted the backdrop for the clinical reviews that are
to follow in this text during his delivery of the Leon
Schiff State-of-the-Art Lecture entitled "Pathophysiology
of Portal Hypertension" on Monday, November 8,
1999. Dr. Groszmann placed the topic of portal
hypertension in an historical context, then elucidated
our current understanding of the causes of the
splanchnic vasodilatation and the subsequent retention
of water and sodium. Much of his attention was turned
to nitric oxide (NO), particularly endothelial NO, the
production of which appears to be increased by
vascular wall stress. Bringing his comments into the
clinical realm, Dr. Groszmann theorized that nitrates
will likely continue to play a role in the therapy of
portal hypertension because of the ability of these
compounds to donate NO. However, because the action of
nitrates is systemic, rather than selectively
splanchnic, currently available compounds are likely
to be of limited value.[11]
Endoscopic
Therapy of Variceal Hemorrhage
From an endoscopic standpoint, it
seems clear that endoscopic band ligation (EBL) is
supplanting endoscopic sclerotherapy as the most
effective and safe technique for control of hemorrhage
and serial eradication of varices. Gastric varices (GV)
have proven more difficult to treat, often requiring
portosystemic shunting. Williams and colleagues from
University of Virginia provide a report of the early
US experience with enbucrilate injection for control
of GV bleeding. Of 11 patients treated, 10 had
resolution of index bleed, while 1 had recurrence. Two
patients died from previously identified malignancy
during the period of observation. There was no damage
to endoscopic equipment, a concern given the adhesive
nature of enbucrilate. Cost of care compared favorably
with standard care of these patients.[12] Such a technique, if successful in control and
eradication of GV, will prove most useful.
Pharmacologic
Therapy of Variceal Hemorrhage
Beta adrenergic blockade is
accepted as effective primary prophylaxis against
variceal hemorrhage in patients with large esophageal
varices. The studies that have shown this benefit used
sufficient beta-blockade to lower pulse by 25% or to
55 beats per minute. Some investigators have suggested
that even these parameters are insufficient to insure
adequate lowering of the portosystemic gradient,
thereby preventing hemorrhage. Peron and his French
group used hepatic venous pressure gradient (HVPG) to
assess adequacy of primary and secondary prophylaxis
in 22 patients with cirrhosis and varices. Propranolol
at 160 mg/day lowered the portosystemic gradient in
15/22 patients to below 12 mmHg or reduced it by 20%.
Four more patients were classified as responders by
these criteria, with the addition of isosorbide
mononitrate (IMN) 60 mg qd. Four patients bled during
follow-up, including 2 "responders,"
suggesting that reduction of HVPG by 20% may be an
inadequate parameter in prophylaxis of variceal
hemorrhage.[13]
Dr.
Minyana and colleagues presented data comparing EBL to
nadolol (NAD) plus IMN in the prevention of variceal
rebleeding once primary hemostasis had been achieved.
Five days after control of bleeding, 139 patients were
randomized to EBL versus NAL (reducing HR [heart rate]
by 25% but > 55 beats per minute) plus IMN (up to
40 mg bid). Drug therapy was as successful in
preventing rebleeding as EBL in this patient
population, with fewer complications. These data must
be interpreted with caution, however, because the 43%
rebleeding rate observed in the EVL group was rather
high.[14]
Lopez-Balaguer
and colleagues presented a careful hemodynamic study
in cirrhotic patients given a combination of
somatostatin and IMN. Somatostatin has been shown to
decrease splanchnic pressure and has proven useful in
control of variceal hemorrhage. In addition, IMN
provides further vasodilatation, presumably through
its role as a NO donor, as discussed previously. In
this study, 39 patients were given IMN in addition to
somatostatin. Significant decreases were seen in mean
arterial pressure and hepatic venous pressure
gradient, the latter primarily due to a decrease in
wedged hepatic vein pressure. Despite these results,
decrease in mean arterial pressure may limit the
usefulness of this combination.[15]
Cales
reported on 196 patients admitted for variceal
hemorrhage or portal hypertensive bleeding randomized
to vapreotide, a somatostatin analogue, or placebo,
within a mean of 2.2 hours. Endoscopic therapy was
provided within a mean of 3.1 hours after admission.
Less bleeding was observed at the time of endoscopy,
with associated higher hemostasis rates and less blood
transfusion. No significant difference in 5- or 42-day
survival was seen. Time will tell if this compound
will become available for trials in the US.[16]
El Atti
and coworkers took an alternative pharmacologic
approach to variceal hemorrhage. Recognizing the known
action of sumatriptan in raising lower esophageal
sphincter pressure by its peripheral action of 5HT
receptor, these investigators theorized a lowering of
variceal pressure with this agent. Ten patients were
given sumatriptan, 10 mg sq. There was a significant
lowering of variceal pressure as measured with
pressure-sensitive gauge, but no effect on portal or
systemic pressure. The researchers speculate that
variceal pressure is lowered by the elevation of lower
esophageal sphincter pressure.[17]
Primary
Prophylaxis of Variceal Hemorrhage
Clearly, primary prophylaxis of
variceal hemorrhage cannot take place unless the
appropriate patients are selected and tested. Dr.
Arguedas and colleagues from the University of Alabama
reported on 69 consecutive patients undergoing
evaluation for orthotopic liver transplantation (OLT).
Of these patients, 33% presented with variceal
bleeding as original presentation of liver disease.
Twelve others developed bleeding after the diagnosis
of cirrhosis, only 1 of whom had undergone screening
exam. Only 55% of the remaining patients in the cohort
have been screened to date. The researchers correctly
call for more vigilant screening of patients with
cirrhosis for varices to allow primary prophylaxis.[18]
Saeian and associates attempted to provide us with
information to ease that screening process by
demonstrating the acceptability of unsedated
transnasal and peroral endoscopy (5.3 mm outer
diameter) for variceal screening in 9 patients.[19]
Dr.
Merkel and his colleagues in Padua reported a primary
prophylaxis trial comparing NAD monotherapy with NAD
plus IMN. One hundred forty-six patients with
cirrhosis and known esophageal varices, but no
bleeding, were treated for 7 years. Sixteen in the NAD
group and 8 in the combination therapy group bled. The
cumulative bleeding risk was higher in the NAD group
(29%) versus the NAD/IMN group (12%). Addition of IMN
did not increase incidence of liver failure,
development of ascites, or renal insufficiency;
however, 4 patients requested discontinuation of IMN
due to side effects.[20]
During
the plenary sessions, Dr. Lui outlined the experience
of his group from Scotland regarding the best approach
to primary prophylaxis. Previous experiences with
sclerotherapy as a means of prophylaxis have proven
disappointing. The role of EBL in this capacity is as
yet unproven. In their study, 172 patients with
cirrhosis and no history of bleeding were stratified
by treatment into EBL, propranolol, or isosorbide
mononitrate groups. Band ligation was found to be
superior to IMN, but not significantly different from
propranolol, despite a 24% withdrawal from the
propranolol group due to side effects. During a rather
lively question and answer session following the
presentation, concerns with the high bleeding rate in
the pharmacologic groups were expressed. Clearly,
further investigation into the role of endoscopic
prophylaxis of variceal hemorrhage is warranted.[21]
Issues
in TIPS
The use of TIPS has proven
invaluable in the therapy of refractory variceal
hemorrhage by lowering the portosystemic gradient.
More recently, this method of portal decompression has
been employed in the management of patients with
refractory ascites. Unfortunately, TIPS has been
associated with the development of portosystemic
encephalopathy. Furthermore, stenosis of the shunt
occurs in nearly half of patients undergoing the
procedure within the first 6 months.
Russo
and associates looked at 90 consecutive patients who
underwent TIPS over a 6-year period. Those with
relatively maintained synthetic function had higher
incidence of TIPS stenosis, determined
angiographically, than those with abnormal INR. The
researchers suggested that TIPS is not indicated in
those patients with portal hypertension and relatively
preserved prothrombin time.[22]
Further
data on predicting the complications of TIPS were
provided in a poster presented by El Atti in which 79
patients with emergently placed TIPS for variceal
hemorrhage were analyzed. Twenty-one of 79 were
determined to have bled from gastric fundal varices (GV),
while 58 bled from esophageal varices (EV). Fifty-two
percent of patients with GV had large spontaneous
portosystemic shunts, half of which required
embolization to control hemorrhage. Forty percent of
the GV group with large spontaneous shunts versus 8%
of the EV group had early TIPS thrombosis. The
investigators suggested that anticoagulation may
therefore be warranted in the group with large
spontaneous portosystemic shunts.[23]
Pomier-Layrargues
and colleagues provided data to help predict which
patients who undergo TIPS will have resistant
encephalopathy. In their study, 219 patients who
underwent TIPS were reported. One hundred eighteen
subjects had preprocedure flow, while 31 had either
hepatofugal, back-and-forth flow, or portal vein
thrombosis. No patient in the second group had severe
encephalopathy after TIPS, while 16.5% of the first
group did. The researchers speculated that reversed or
absent portal flow is protective against severe
post-TIPS encephalopathy.[24]
These
papers, which illuminate the difficulties in managing
the patient after TIPS, support the current trend to
view this procedure as a temporizing therapy or as a
bridge toward ultimate OLT.
References
1.
Roberts LR, Kamath PS. Pathophysiology and
treatment of variceal hemorrhage. Mayo Clin Proc
1996;71(10):973-983.
2.
Poynard T, Cales P, Pasta L, et al. Beta-adrenergic-antagonist
drugs in the prevention of gastrointestinal bleeding
in patients with cirrhosis and esophageal varices. An
analysis of data and prognostic factors in 589
patients from four randomized clinical trials. N Engl
J Med 1991;324(22):1532-1538.
3.
Sung JJ, Chung SC, Lai CW, et al. Octreotide
infusion or emergency sclerotherapy for variceal
hemorrhage. Lancet 1993;342:637-641.
4.
Hou MC, Lin HC, Kuo BIT, et al. Comparison of
endoscopic variceal injection sclerotherapy and
ligation for the treatment of esophageal variceal
hemorrhage: a prospective randomized trial. Hepatology
1995;21:1517-1522.
5.
Laine L, Stein C, Sharma V. Randomized
comparison of ligation versus ligation plus
sclerotherapy in patients with bleeding esophageal
varices. Gastroenterology 1996;110:529-533.
6.
Van Ruiswyk J, Byrd JC. Efficacy of
prophylactic sclerotherapy for prevention of first
variceal hemorrhage. Gastroenterology
1992;102:587-597.
7.
Sarin SK, Gupten RKC, Jain AK, Sundaram KR. A
randomized controlled trial of endoscopic variceal
band ligation for primary prophylaxis of variceal
bleeding. Eur J Gastroenterol Hepatol 1996;8:337-342.
8.
Rossle M, Haag K, Ochs A, et al. The
transjugular intrahepatic portosystemic stent-shunt
procedure for variceal bleeding. N Engl J Med
1994;330:165-171.
9.
Collins JC, Rypins EB, Sarfeh IJ.
Narrow-diameter portocaval shunts for management of
variceal bleeding. World J Surg 1994;18:211-215.
10.
Burroughs AK, Hamilton G, Phillips A, et al. A
comparison of sclerotherapy with acute transection of
the esophagus for the emergency control of bleeding
from esophageal varices. N Engl J Med
1989;321:857-862.
11.
Groszmann RJ. Pathophysiology of portal
hypertension. Program and abstracts of the 50th Annual
Meeting and Postgraduate Courses of the American
Association for the Study of Liver Diseases; November
5-9, 1999; Dallas, Texas.
12.
Williams JM, Hespenheide EE, Lucas LJ, et al.
Enbucrilate (histoacryl) for the treatment of bleeding
gastric varices: a cost analysis. Program and
abstracts of the 50th Annual Meeting and Postgraduate
Courses of the American Association for the Study of
Liver Diseases; November 5-9, 1999; Dallas, Texas.
Abstract 231.
13.
Peron JM, Asnacios A, Sanchez J, et al.
Adjustment of portal hypertension medical treatment
according to the hemodynamic response: prospective
study of 22 patients. Program and abstracts of the
50th Annual Meeting and Postgraduate Courses of the
American Association for the Study of Liver Diseases;
November 5-9, 1999; Dallas, Texas. Abstract 229.
14.
Minyana J, Gallego A, Vera JS, et al.
Endoscopic ligation versus naldolol plus
isosorbide-s-mononitrate for the prevention of
variceal rebleeding. Program and abstracts of the 50th
Annual Meeting and Postgraduate Courses of the
American Association for the Study of Liver Diseases;
November 5-9, 1999; Dallas, Texas. Abstract 215.
15.
Lopez-Balaguer JM, Sola-Vera J, Minyana J, et
al. Hemodynamic effects of combined therapy with
somatostatin and isosorbide-s-mononitrate in patients
with cirrhosis and portal hypertension. Program and
abstracts of the 50th Annual Meeting and Postgraduate
Courses of the American Association for the Study of
Liver Diseases; November 5-9, 1999; Dallas, Texas.
Abstract 222.
16.
Cales P. Early administration of vapreotide, a
new somatostatin analogue, and endoscopic therapy for
acute portal hypertensive bleeding in patients with
cirrhosis. Program and abstracts of the 50th Annual
Meeting and Postgraduate Courses of the American
Association for the Study of Liver Diseases; November
5-9, 1999; Dallas, Texas. Abstract 1035.
17.
El Atti EA, Nevens F, Couli B, et al.
Sumatriptan reduces variceal pressure without
affecting portal pressure. Program and abstracts of
the 50th Annual Meeting and Postgraduate Courses of
the American Association for the Study of Liver
Diseases; November 5-9, 1999; Dallas, Texas. Abstract
238.
18.
Arguedas MR, McGuire BM, Fallon MB, et al. The
use of screening and preventive therapies for
esophageal varices in patients referred for evaluation
of orthotopic liver transplantation. Program and
abstracts of the 50th Annual Meeting and Postgraduate
Courses of the American Association for the Study of
Liver Diseases; November 5-9, 1999; Dallas, Texas.
Abstract 220.
19.
Saeian K, Staff DM, Townsend W, et al. A new
approach to screening for esophageal varices. Program
and abstracts of the 50th Annual Meeting and
Postgraduate Courses of the American Association for
the Study of Liver Diseases; November 5-9, 1999;
Dallas, Texas. Abstract 219.
20.
Merkel C, Marin R, Sacerdoti D, et al.
Long-term results of a clinical trial of nadolol with
or without isosorbide mononitrate for primary
prophylaxis of variceal bleeding in cirrhosis. Program
and abstracts of the 50th Annual Meeting and
Postgraduate Courses of the American Association for
the Study of Liver Diseases; November 5-9, 1999;
Dallas, Texas. Abstract 217.
21.
Lui HF, Stanley AJ, Forrest EH, et al. Primary
prophylaxis of variceal haemorrhage: a randomised
controlled trial comparing band ligation, propranolol
and isosorbide mononitrate. Program and abstracts of
the 50th Annual Meeting and Postgraduate Courses of
the American Association for the Study of Liver
Diseases; November 5-9, 1999; Dallas, Texas. Abstract
632.
22.
Russo MW, Honeycutt K, Jacques PF, et al.
Prothrombin time, but not platelet count, predicts
stenosis after transjugular intrahepatic portosystemic
shunt (TIPS). Program and abstracts of the 50th Annual
Meeting and Postgraduate Courses of the American
Association for the Study of Liver Diseases; November
5-9, 1999; Dallas, Texas. Abstract 225.
23.
El Atti EA, Stockx L, Maleux G, et al. Patients
with fundal variceal bleeding have frequently large
portosystemic shunts which makes them at risk for
stent thrombosis and encephalopathy after TIPS.
Program and abstracts of the 50th Annual Meeting and
Postgraduate Courses of the American Association for
the Study of Liver Diseases; November 5-9, 1999;
Dallas, Texas. Abstract 226.
24.
Pomier-Layrargues G, Hassoun Z, Lafortune M, et
al. Relationship between pre-TIPS liver perfusion by
the portal vein and the incidence of post-TIPS chronic
recurrent hepatic encephalopathy. Program and
abstracts of the 50th Annual Meeting and Postgraduate
Courses of the American Association for the Study of
Liver Diseases; November 5-9, 1999; Dallas, Texas.
Abstract 529.
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