BRIEF REPORT

Portal Venous Remodeling After Endovascular

Reduction of Pediatric Autogenous
Portosystemic Shunts
Jessica K. Stewart, BS, William T. Kuo, MD, David M. Hovsepian, MD,
Lawrence V. Hofmann, MD, Clark A. Bonham, MD,
and Daniel Y. Sze, MD, PhD

ABSTRACT

Patients with autogenous native vessel portosystemic shunts, whether surgical or congenital, may experience complications of excess
shunt flow, including hepatopulmonary syndrome (HPS), hepatic encephalopathy (HE), and hepatic insufficiency. The authors
explored endovascular reduction or occlusion of autogenous portosystemic shunts using methods commonly employed in transjugular
intrahepatic portosystemic shunt (TIPS) reduction in four pediatric patients. Before treatment, the patients had hypoplastic, atrophic,
or thrombosed portal veins. Following intervention, symptoms of overshunting resolved or improved in all patients without major
complications. The innate plasticity of the pediatric portal venous system allowed for hypertrophy or development and maturation of
cavernous transformations to accommodate increased hepatopetal blood flow and pressure.

ABBREVIATIONS

HE ⫽ hepatic encephalopathy, HPS ⫽ hepatopulmonary syndrome, IVC ⫽ inferior vena cava, SMV ⫽ superior mesenteric
vein, TIPS ⫽ transjugular intrahepatic portosystemic shunt

Excess blood flow through portosystemic shunts and the requires the existence of a patent portal vein able to carry
associated decreased portal perfusion of the liver may occur increased flow into the liver.
with both man-made and spontaneous shunts (1–3). Signs We report four cases of pediatric patients with autog-
and symptoms can be life-threatening and can include he- enous native vessel (non-TIPS) portosystemic shunts who
patic encephalopathy (HE), hepatopulmonary syndrome underwent percutaneous shunt reduction or occlusion. The
(HPS), and hepatic insufficiency or failure. Options for the methods used in this procedure were similar to those com-
treatment of overshunting include medical management monly used in TIPS reduction. In contrast to TIPS patients,
with cathartics and antibiotics, partial or complete surgical however, our patients all had hypoplastic or thrombosed
shunt ligation, and liver transplantation. For the treatment portal veins, so subsequent improvement of symptoms re-
of overshunting through transjugular intrahepatic portosys- lied on the plasticity of the portal system to undergo hy-
temic shunts (TIPS), various endovascular flow-reducing pertrophy or cavernous transformation to accommodate in-
methods have been devised for partial restoration of hepa- creased portal venous blood flow into the liver. The
topetal portal flow (4,5). The success of these methods institutional review board approved this retrospective re-
port. All data were handled in compliance with the Health
Insurance Portability and Accountability Act.
From the Divisions of Interventional Radiology (J.K.S., W.T.K., D.M.H., L.V.H.,
D.Y.S.), and Transplantation, (C.A.B.), H-3646, Stanford University Medical
Center, 300 Pasteur Drive, Stanford, CA 94305-5642. Received November 30,
2010; final revision received January 12, 2011; accepted January 24, 2011. CASE REPORTS
Address correspondence to D.Y.S.; E-mail: dansze@stanford.edu

Presented at the SIR 2011 Annual Meeting. Patient 1

None of the authors have identified a conflict of interest. An 11-month-old girl presented with worsening cyanosis
and tachypnea since birth (Table 1). She was mildly de-
© SIR, 2011
velopmentally delayed and in the 5th percentile for height
J Vasc Interv Radiol 2011; 22:1199 –1205 and weight. Imaging showed an absent extrahepatic portal
DOI: 10.1016/j.jvir.2011.01.438 vein, a congenital shunt connecting the superior mesenteric

Downloaded for Dai Hoon Han (dhhan@yuhs.ac) at Yonsei University College of Medicine from ClinicalKey.com by Elsevier on
November 02, 2023. For personal use only. No other uses without permission. Copyright ©2023. Elsevier Inc. All rights reserved.
1200 䡲 Portal Venous Remodeling Stewart et al 䡲 JVIR

Table 1. Patient Demographics, Shunt Characteristics, and Indications for Shunt Reduction

Interval Between
Shunt Creation
Patient Indication for Shunt and Reduction or
No./Age/Sex Diagnose(s) Shunt Type Reduction Occlusion
1/11 mo/F Abernethy malformation (type I) Congenital Hepatopulmonary NA
(splenomesentericorenal) syndrome
2/14 mo/F Abernethy malformation (type Congenital Hepatopulmonary NA
I); biliary atresia; orthotopic (splenomesentericoazygos) syndrome
whole liver transplant
3/10 y/M Primary sclerosing cholangitis; Surgical (side-to-side Hepatic encephalopathy, 33 mo
living donor left lateral lobe splenorenal shunt) behavioral issues
liver transplant; portal vein
thrombosis, portal
hypertension
4/11 y/M Methylene tetrahydrofolate Surgical (proximal splenorenal Hepatic encephalopathy, 10 mo
reductase deficiency; portal shunt, splenectomy) behavioral issues
vein thrombosis, portal
hypertension

NA ⫽ not applicable.

vein (SMV) and splenic vein to the left renal vein and and was found to have pulmonary hypertension and diffuse
hemiazygos vein, interrupted inferior vena cava (IVC) with pulmonary arterial and venous dilatation with intrapulmo-
azygos continuation, polysplenia, heterotaxia, intestinal nary shunting, indicative of HPS (8).
malrotation, and patent foramen ovale—a constellation of A test balloon occlusion of the shunt resulted in an
congenital anomalies most consistent with Abernethy mal- increase of the portosystemic gradient by 12 mm Hg. Be-
formation type I (1,2,6,7). The patient required 2 L oxygen cause high gradients are associated with complications,
by nasal cannula to maintain an oxygen saturation of 85% abrupt occlusion by embolization of the shunt was thought

Table 2. Technical Details and Hemodynamics of Shunt Reductions and Occlusions

Minimum Shunt Diameter (mm)

Reduction or Occlusion Technique and % Change of

Patient No. Device Before After Cross Section
1 1: Hourglass reducing stent graft (10 ⫻ 10 5.5 ⫺70
20 mm Wallgraft narrowed to 5.5
mm diameter by Prolene suture)
2: Embolization (AMPLATZER plugs 12 5.5 0 ⫺100
mm and 14 mm)

2 Embolization (AMPLATZER II plug 14 12 0 ⫺100

mm)
3 Hourglass reducing stent graft (14 ⫻ 13 5 ⫺85
50 mm Wallgraft narrowed to 5 mm
diameter by Prolene suture)
4 1: Parallel stent/stent graft (10 ⫻ 20 10 7 ⫺51
mm Wallgraft, 8 ⫻ 12 mm Herculink
Plus)
2: Hourglass reducing stent graft (10 ⫻ 10 4 ⫺84
50 mm Wallgraft narrowed to 4 mm
diameter by Prolene suture)

Downloaded for Dai Hoon Han (dhhan@yuhs.ac) at Yonsei University College of Medicine from ClinicalKey.com by Elsevier on
November 02, 2023. For personal use only. No other uses without permission. Copyright ©2023. Elsevier Inc. All rights reserved.
Volume 22 䡲 Number 8 䡲 August 䡲 2011 1201

Figure 1. (a) Superior mesenteric venography performed through an occlusion balloon introduced through the azygos vein and
splenomesentericorenal shunt in patient 1 with an Abernethy type I malformation showed a severely hypoplastic portal vein (arrow)
leading to a nascent cavernous transformation. This vessel was not apparent without balloon occlusion. The lumen of the shunt was
reduced from 10 mm to 5.5 mm using a suture-constrained stent graft, increasing the portosystemic gradient from 0 to 6 mm Hg.
(b) Venography performed 2 months later showed that the reducing stent graft (black arrow) had promoted interval hypertrophy of
the extrahepatic portal vein from 1 mm to 3 mm (white arrow). The portosystemic gradient had decreased to 4 mm Hg, with test
balloon occlusion increasing the portosystemic gradient only to 6 mm Hg. A competing portosystemic shunt leading to intercostal
veins draining into the epidural plexus (arrowhead) was treated with coiling and embolization, and embolization of the splenomes-
entericorenal shunt was performed with two AMPLATZER vascular plugs. (c) Gadolinium-enhanced magnetic resonance (MR)
angiogram obtained 15 months after embolization showed interval growth of the extrahepatic portal vein to 8 mm diameter (arrow).
All signs and symptoms of hepatopulmonary syndrome (HPS) had resolved.

Table 2. Continued

Portosystemic Pressure Gradient (mm Hg) Diameter of Main Portal Vein (mm)

After (Imaging
With Test Occlusion Before Method, Elapsed %
Before Balloon Inflated After Increase (Imaging Method) Time) Change Vessel Treated
0 12 6 6 1 (portal 3 (portal ⫹200 Congenital portosystemic
venogram) venogram, 2 mo) shunt

4 6 6 2 3 (portal 8 (MR angiogram, ⫹167,

venogram) 15 mo) total
⫹700
2 5 5 3 2 (portal 6 (CT) ⫹200 Congenital portosystemic
venogram) shunt
8 13 11 3 3 (MR imaging) 7 (ultrasonography, ⫹133 Native splenic vein
6 mo) adjacent to surgical
splenorenal shunt
3 NA 8 5 2 (largest 2 (portal 0 Surgical proximal
collateral, CT) venogram, 2 mo) splenorenal shunt

3 20 16 13 2 (portal 6 (CT, MR imaging, ⫹200

venogram) 6 y)

CT ⫽ computed tomography, MR ⫽ magnetic resonance, NA ⫽ not available.

Downloaded for Dai Hoon Han (dhhan@yuhs.ac) at Yonsei University College of Medicine from ClinicalKey.com by Elsevier on
November 02, 2023. For personal use only. No other uses without permission. Copyright ©2023. Elsevier Inc. All rights reserved.
1202 䡲 Portal Venous Remodeling Stewart et al 䡲 JVIR

Table 3. Clinical Outcomes and Laboratory Data Before and After Shunt Reduction or Occlusion

Serum Serum Total International

Ammonia Bilirubin Normalized
(mmol/L) (mg/dL) Ratio Oxygenation (% Saturation)
Patient
No. Before After Before After Before After Before After
1 29 27 0.7 0.5 1.2 1.0 85% on 2 L/min nasal cannula 96% on room air
2 59 13 0.9 0.3 1.6 1.1 92% on 2 L/min nasal cannula 97% on room air
3 79 66 2.0 1.0 1.6 1.6 NA NA
4 179 14 0.6 0.4 1.7 1.3 NA NA

NA ⫽ not applicable.

to be too risky. Reduction of the shunt was performed using reconstructed by an end-to-side anastomosis of the allograft
a custom suture-constrained, hourglass-shaped reducing portal vein to the native SMV.
stent graft (Wallgraft; Boston Scientific, Natick, Massachu- Postoperatively, the patient required prolonged venti-
setts), resulting in an increase in the portosystemic pressure latory support for paralysis of the right hemidiaphragm and
gradient from 0 to 6 mm Hg (Table 2 and Fig 1). The stent tracheobronchomalacia. Respiratory function gradually de-
graft was constrained with 4-0 polypropylene suture teriorated, and 6 months after transplantation, perfusion
(Prolene; Ethicon/J&J, Somerville, New Jersey). Two ad- lung scintigraphy was performed that showed an intrapul-
jacent constraints with diameters of 5.5 mm and 7 mm were monary shunt fraction of 39% (normal ⬍7%), supporting a
placed to allow for adjustment of diameter with an angio- diagnosis of HPS. Venography showed an atrophic portal
plasty balloon in case complications of portal hypertension vein with splanchnic flow preferentially coursing through
resulted. the large shunt, likely from a steal phenomenon. After a
No such complications occurred, however, and by 2 balloon test occlusion resulted in an increase of the porto-
months after the procedure, the patient’s venous ammonia systemic gradient by only 3 mm Hg, the shunt was embo-
levels decreased from 66 ␮mol/L to 29 ␮mol/L, the diam- lized using an AMPLATZER 2 plug (AGA Medical). At
eter of the main extrahepatic portal collateral vein increased 5-month follow-up, she maintained an oxygen saturation of
from 1 mm to 3 mm (Fig 1), and her oxygen requirements 97% on room air (Table 3). Repeat imaging by computed
decreased. The portosystemic gradient with an occlusion tomography (CT) angiogram showed hypertrophy of the
balloon inflated was only 6 mm Hg, so embolization of the transplanted main portal vein from 2 mm to 6 mm in
reducing stent was performed using AMPLATZER plugs diameter (Fig 2).
(AGA Medical, Plymouth, Minnesota), along with adjunc-
tive coil embolization of spontaneous shunts between the Patient 3
splenic and left intercostal veins (VortX; Boston Scientific). A 10-year-old boy was treated for behavioral abnormalities
Within 2 months, the patient’s HPS completely resolved, related to HE. The patient had a history of Langerhans cell
and she no longer required supplemental oxygen. Imaging histiocytosis X and liver failure secondary to primary scle-
performed 15 months after embolization confirmed matu- rosing cholangitis and underwent a living-related left lateral
ration of the cavernous transformation with the dominant segment liver transplant at age 10 months. At age 7 years,
vessel measuring 8 mm in diameter. In 34 months of he developed upper gastrointestinal bleeding secondary to
follow-up, she has been removed from the liver transplan- portal vein thrombosis and underwent a side-to-side sple-
tation candidacy list, and is now at the 90th percentile for norenal shunt. After shunt creation, the patient developed
height and 75th percentile for weight. hyperammonemia, coagulopathy, and progressively antiso-
cial behavior. Magnetic resonance (MR) imaging and
Patient 2 venography revealed a 3-mm extrahepatic collateral vessel
A 14-month-old girl with type I Abernethy malformation coursing from an SMV branch to the hepatic hilum, where
presented with HPS 6 months after undergoing liver trans- it supplied the intrahepatic portal circulation (Fig 3).
plantation. Congenital defects included an atrial septal de- An hourglass-shaped stent graft reduction was performed,
fect; left atrial isomerism; biliary atresia; heterotaxy with but the stent graft was placed in the native splenic vein to
malrotation of the bowel; azygos continuation of the IVC; promote hepatopetal flow from the SMV, while maintaining
congenital absence of the portal vein; and a large congenital shunting of flow from the splenic vein into the left renal vein.
shunt with inflow from the SMV, left renal vein, and In 10 months of follow-up, behavioral issues have resolved,
splenic vein into the hemiazygos vein. She underwent and the patient has resumed attending public school and ex-
Ladd’s procedure for malrotation, patch repair of the atrial tracurricular activities. An abdominal ultrasound examination
septal defect, and placement of an atrial pacemaker. During confirmed improved blood flow through the hypertrophied
liver transplantation at age 8 months, the portal vein was extrahepatic collateral and intrahepatic portal veins.

Downloaded for Dai Hoon Han (dhhan@yuhs.ac) at Yonsei University College of Medicine from ClinicalKey.com by Elsevier on
November 02, 2023. For personal use only. No other uses without permission. Copyright ©2023. Elsevier Inc. All rights reserved.
Volume 22 䡲 Number 8 䡲 August 䡲 2011 1203

Figure 2. (a) Oblique coronal thin-slab maximum intensity projection of a computed tomography (CT) angiogram of the splanchnic
circulation 6 months after liver transplantation for biliary atresia and congenital absence of the portal vein in patient 2 showed atrophy
of the transplant main portal vein (arrow), possibly secondary to steal phenomenon from a large congenital splenomesentericoazygos
shunt. Balloon test occlusion of the shunt increased the portosystemic gradient from 2 mm Hg to 5 mm Hg, but the portal vein
diameter remained 2 mm. Embolization of the shunt was performed with an AMPLATZER II vascular plug, preserving venous drainage
from the spleen and left kidney into the hemiazygos vein, while redirecting superior and inferior mesenteric venous flow into the portal
vein. (b) Follow-up CT angiogram 5 months later showed the vascular plug occluding the shunt (asterisk) and hypertrophy of the portal
vein to 6 mm diameter (arrow). Hepatopulmonary syndrome (HPS) symptoms were essentially resolved.

Figure 3. (a) Venogram of superior mesenteric vein (SMV) in patient 3 showed a vein with slow flow in the right upper quadrant
(arrow), flowing toward the hilum of the left lateral segment liver transplant. The main outflow was through the side-to-side surgical
splenorenal shunt in this encephalopathic patient, and the portosystemic gradient was 3 mm Hg. Inflow from the spleen through the
shunt appeared as a filling defect of unopacified blood (arrowhead). (b) Composite image after placement of a suture-constrained
stent graft in the splenic vein (arrow) showed more robust flow through the collateral vein, possibly an omental vein, filling a small
cavernous transformation and an intrahepatic portal vein (arrowhead). The gradient between the SMV and inferior vena cava (IVC)
was increased to 5 mm Hg, but outflow from the spleen remained unimpeded by the upstream placement of the stent graft.
Ultrasonography performed 6 months later showed a doubling in diameter of the intrahepatic and extrahepatic portal vessels.

Patient 4 vein thrombosis, and variceal hemorrhage due to methylene

An 11-year-old boy underwent reduction of a surgical shunt tetrahydrofolate reductase deficiency. At age 10 years, he
because of behavioral issues related to HE. He initially underwent splenectomy and creation of a proximal sple-
presented with splenomegaly, thrombocytopenia, portal norenal shunt, but he still had recurrent episodic variceal

Downloaded for Dai Hoon Han (dhhan@yuhs.ac) at Yonsei University College of Medicine from ClinicalKey.com by Elsevier on
November 02, 2023. For personal use only. No other uses without permission. Copyright ©2023. Elsevier Inc. All rights reserved.
1204 䡲 Portal Venous Remodeling Stewart et al 䡲 JVIR

Figure 4. (a) Venogram of the superior mesenteric vein (SMV) of patient 4 showed rapid flow through a surgical proximal splenorenal
shunt into the left renal vein and inferior vena cava (IVC). The pressure gradient between the SMV and IVC was 3 mm Hg, and there
was no appreciable hepatopetal flow in this encephalopathic patient. (b) Flow reduction was initially performed by using a parallel
stent (Herculink Plus; Guidant, Santa Clara, California) and stent graft (Wallgraft) (arrowheads), which failed within 3 months when the
constant outward force of the stent graft apparently resulted in dilatation of the native vessel, allowing full expansion of the stent graft.
A suture-constrained stent graft was then placed (arrow), increasing the portosystemic gradient to 16 mm Hg and redirecting flow into
a poorly developed cavernous transformation. Imaging over 6 years of follow-up has shown progressive enlargement and maturation
of the cavernous transformation.

hemorrhage. His disruptive behavior led to a diagnosis of DISCUSSION

attention-deficit/hyperactivity disorder. Electroencephalog-
Autogenous or native vessel portosystemic shunts may be
raphy was uninformative, but laboratory examination re-
vealed severe hyperammonemia, which did not respond congenital or surgically created. Congenital portosystemic
well to medical management. shunts were first described by Abernethy in 1793 (6) and
The splenorenal shunt was reduced using the parallel may be either intrahepatic or extrahepatic. Intrahepatic
stent and stent graft method (4), which has become a shunts include patent ductus venosus and congenital porto-
preferred method for TIPS reduction (Fig 4). This reduction systemic fistulas (1,2). Extrahepatic shunts (Abernethy mal-
increased the portosystemic pressure gradient from 3 mm Hg formations) are classified based on the preservation of por-
to 8 mm Hg, but early clinical improvement was not sustained. tal perfusion of the liver; type I involves absence of
Imaging 3 months later revealed full expansion of the stent perfusion due to aplasia or severe hypoplasia of the portal
graft, likely secondary to lack of mechanical support around vein. Type II involves decreased perfusion due to a side-
the autogenous shunt (provided by the TIPS stent and sur- to-side shunt between a patent portal vein and the IVC.
rounding liver parenchyma when this method is used in TIPS Associated congenital anomalies such as the ones seen in
reduction). A second reduction was performed using an hour- the patients described here are more commonly seen with
glass-shaped stent graft (Table 2). type I malformation, but ambiguity of classification persists
In more than 6 years of follow-up, ammonia levels (1,2,7).
have normalized, hepatic synthetic function has improved, Surgical portosystemic shunts are created for the man-
and the diagnosis of attention-deficit/hyperactivity disorder agement of complications of portal hypertension and are
has been rescinded. However, the patient continues to ex- usually created using native vessels. They are frequently
perience periodic recurrence of variceal hemorrhage, re- preferred over TIPS in pediatric patients because of better
quiring banding of esophageal varices every 2–3 years. long-term patency, which may be 97% at 10 years (10). The
Imaging revealed a significant increase in cavernous trans- Rex (mesentericoportal) and Warren (distal splenorenal)
formation of the portal vein, to the point of asymptomatic shunts are performed most commonly and partially restore
dilatation of the intrahepatic biliary ductal system second- or preserve hepatopetal portal flow (11).
ary to compression of the central bile ducts by the enlarged All portosystemic shunts may result in overshunting,
vessels of the cavern, a condition referred to as vascular which can manifest as HE, HPS, or hepatic insufficiency.
biliopathy secondary to portal cavernoma (9). Mild cases may be managed medically, but severe shunt-

Downloaded for Dai Hoon Han (dhhan@yuhs.ac) at Yonsei University College of Medicine from ClinicalKey.com by Elsevier on
November 02, 2023. For personal use only. No other uses without permission. Copyright ©2023. Elsevier Inc. All rights reserved.
Volume 22 䡲 Number 8 䡲 August 䡲 2011 1205

related HE, HPS, or hepatic insufficiency refractory to be especially pronounced because of high levels of angio-
medical management requires invasive intervention, such genic and vasoactive substances elevated by portal hyper-
as surgical ligation (12) or transplantation (8), which can tension, such as nitric oxide, endothelin, and prostacyclins
achieve a 76% 5-year survival rate for patients with HPS, (14). The trophic nature of portal flow may also enhance
equivalent to the rate in liver transplant patients without remodeling (15). As long as patients do not have sinusoidal
HPS. or intrahepatic obstruction, increasing the pressure and flow
Our case series shows that refractory complications of of the splanchnic venous system seems to promote stable
overshunting may be treated by endovascular methods. development and maturation of hepatopetal portal channels.
Although many options for restriction of flow through a
TIPS are feasible (4,5), only a few of these are appropriate
for application in the native vessels of a congenital or ACKNOWLEDGMENTS
surgical shunt, which may be too tortuous to allow delivery The authors thank Drs. Nishita Kothary, Gloria Hwang, and
of a stiff device such as a Wallgraft. Two of our patients John Louie for critical review of the manuscript and Drs.
required multiple sites of venous access to achieve delivery Carlos Esquivel and William Berquist for their collabora-
of the device. All options are challenging to deploy in tion and guidance on treatment planning.
infants and children, and despite using the minimum length
devices, the extra length of a constrained Wallgraft proba-
bly resulted in partial protrusion of devices into the renal REFERENCES
veins of two of the patients (1 and 4). All four of our
1. Stringer MD. The clinical anatomy of congenital portosystemic venous
patients responded well enough to avoid liver transplanta- shunts. J Clin Anat 2008;21:147–157.
tion or retransplantation, in part because overshunting was 2. Murray CP, Yoo SJ, Babyn PS. Congenital extrahepatic portosystemic
due to portal obstruction, not to hepatocellular or sinusoidal shunts. Pediatr Radiol 2003;33:614 – 620.
3. Alvarez AE, Ribeiro AF, Hessel G, Baracat J, Riberio JD. Abernethy
disease. Although hepatic insufficiency was not the primary malformation: one of the etiologies of hepatopulmonary syndrome. Pe-
indication for intervention in any of these patients, synthetic diatr Pulmonol 2002;34:391–394.
function improved in each of them (Table 3). Had any of 4. Madoff DC, Wallace MJ, Ahrar K, Saxon RR. TIPS-related hepatic
encephalopathy: management options with novel endovascular tech-
the surgical shunts been performed to treat cirrhosis or niques. Radiographics 2004;24:31–36.
other intrinsic liver disease, development or maturation of 5. Saket RR, Sze DY, Razavi MK, et al. TIPS reduction with use of stents
collateral vessels would have been less likely after shunt or stent-grafts. J Vasc Interv Radiol 2004;15:745–751.
6. Abernethy J. Account of two instances of uncommon formation in the
reduction, and reduction would have been more likely to viscera of the human body. Phil Trans R Soc 1793;83:59 – 66.
result in complications. 7. Morgan G, Superina R. Congenital absence of the portal vein: two
cases and a proposed classification system for portasystemic vascular
The main risk of the interventions presented here was
anomalies. J Pediatr Surg 1994;29:1239 –1241.
increased portal hypertension and resulting complications, 8. Rodriguez-Roisin R, Krowka MJ. Hepatopulmonary syndrome—a liver-
such as variceal hemorrhage and ascites. This risk was induced lung vascular disorder. N Engl J Med 2008;358:2378 –2387.
9. Perlemuter G, Bejanin H, Fritsch J, et al. Biliary obstruction caused by
especially high in our cohort, none of whom had a normal portal cavernoma: a study of 8 cases. J Hepatol 1996;25:58 – 63.
portal vein to carry hepatopetal flow. Nevertheless, only 10. Orloff MJ, Orloff MS, Girard B, Orloff SL. Bleeding esophagogastric
one patient experienced variceal hemorrhage and with varices from extrahepatic portal hypertension: 40 years’ experience with
portal-systemic shunt. J Am Coll Surg 2002;194:717–728.
unchanged severity, frequency, and response to banding 11. Yoshida H, Mamada Y, Taniai N, Tajiri T. New trends in surgical treat-
compared with before shunt reduction. The abruptness of ment for portal hypertension. Hepatol Res 2009;39:1044 –1051.
hemodynamic changes can be partially mitigated by per- 12. Morikawa N, Honna T, Kuroda T, et al. Resolution of hepatopulmo-
nary syndrome after ligation of a portosystemic shunt in a pediatric
forming reduction rather than complete occlusion and by patient with an Abernethy malformation. J Pediatr Surg 2008;43:E35–E38.
staging reduction and embolization procedures, as we did 13. Kuo MD, Miller FJ, Lavine JE, Peterson M, Finch M. Exploiting phe-
in our patients. notypic plasticity for the treatment of hepatopulmonary shunting in Ab-
ernethy malformation. J Vasc Interv Radiol 2010;21:917–922.
In conclusion, the clinical success and lack of severe 14. Laleman W. Role of vasoactive substances and cellular effectors in the
complications in all four patients may be attributed to the pathophysiology of cirrhotic portal hypertension: the past, the present and the
remarkable plasticity of the pediatric vascular system, future—Georges Brohée Lecture. Acta Gastroenterol Belg 2009;72:9–16.
15. Aller MA, Arias J. Portal systemic collateral development: is it a trophic
which has a tremendous capacity to hypertrophy rapidly adaptation mechanism to hepatic deprivation? J Gastroenterol Hepatol
and to form collateral vessels (13). Portal remodeling may 2006;21:1643–1645.

Downloaded for Dai Hoon Han (dhhan@yuhs.ac) at Yonsei University College of Medicine from ClinicalKey.com by Elsevier on
November 02, 2023. For personal use only. No other uses without permission. Copyright ©2023. Elsevier Inc. All rights reserved.