Congenital Porto-Systemic Shunts: The Role of Interventionnal Radiology
Stéphanie FRANCHI-ABELLA, MD, PhD
Pediatric Radiology Department Hôpital Bicêtre- Hôpitaux Universitaires Paris-Sud Le Kremlin Bicêtre- France
What is a congenital porto-systemic shunt ?
Vascular malformation
Communication between portal system and inferior vena cava (IVC) system
Partial or complete diversion of the portal blood to the IVC
History
First description by Dr John Abernethy 1793 , british surgeon
Anatomical classification of CPSS
Normal vascular anatomy Shunts after main portal vein division
Patent ductus venosus
IVC, left renal vein hepatic veins extra- & intrahepatic portal veins porto-hepatic shunts
Shunts before main portal vein division
End to side shunt “Congenital absence of portal vein “ Side to side shunt Abernethy type 1 Abernethy type 2 Portohepatic Shunt
M HV
LPB Patent Ductus Venosus
DV
Adenoma Side to Side communication between the portal bifurcation and IVC (Abernethy 2) End to Side communication between the main portal vein and the IVC (Abernethy 2)
Adenoma Extrahepatic Side to Side Shunt Between the Inferior Mesenteric Vein and the Right Iliac Vein
Anatomical forms
Ductus Venosus
PortoHepatic
PortoCaval
Before Main Portal Vein Complexe
Review, 265 pts Personnal Series,111 pts O Bernard, Seminars in Liver disease, 2012 Bicêtre, 2015
Congenital porto-systemic shunt Frequency and associated disorders
1/ 30 000 births Isolated or… Associated abnormalities Cardiac malformations Vertebral malformations Polysplenia Sd Heterotaxia Down syndrome, Turner Syndrome …… Physiological changes related to CPSS
hepatotrophic factors
toxic products of digestion
portal deprivation of liver
splanchnic blood bypassing liver
Normal anatomy CPSS Courtesy of Pr F Gauthier
Complications related to CPSS Reported from the 80’s Neonatal Cholestasis, Cytolysis, Coagulation disorders portal Focal Nodular Hyperplasia deprivation Adenomas of liver Regenerative Nodular Hyperplasia Hepatocellular Carcinoma
Pulmonary hypertension Splanchnic A-V pulmonary shunts blood bypassing liver Portosystemic encephalopathy
Hyperammoniemia
O Bernard, Seminars in Liver Disease, 2012 Complications related to CPSS
no complication 68 % 32 % 1 complication 2 complications 3 complications
Neonatal Cholestasis 3 months Liver Tumors 3 months Hepatopulmonary Sd Newborn Pulmonary Hypertension Encephalopathy Others
0 20 40 60 80 O Bernard, Seminars in Liver Disease, 2012 4 yo boy, acute respiratory distress Pulmonary arterial hypertension +++
He died!
(C Cellier CHU Rouen) How to manage CPSS ?
At the beginning: observation
First reports of complications related to CPSS in the 80’s
First attempt of closure in the 90’s: Intrahepatic shunts , patent ductus venosus and side to side extrahepatic shunts (Abernethy 2) Surgery Interventionnal radiology
Liver transplantation in case of complications for end-to side extrahepatic shunts (Abernethy 1)
Maeda, CIVR 1993; Uchino, Franchi-Abella JPGN 2010, Ikeda JPS 1999, Tercier JPS 2006, Why to close CPSS ?
• Restoration of portal flow to the liver = • First hepatic pass • Normal vascularization of hepatocytes
• Reversibility of most complications, at least stabilization: • Encephalopathy • liver tumors • arterio-venous pulmonary shunts • pulmonary hypertension
• Prevention of complications
• Safety and low morbidity of closure procedures
• Risks related to liver transplantation in childhood : infection, Cancer, cardiovascular and renal complications
Franchi-Abella JPGN 2010, O Bernard, Seminars in Liver Disease, 2012; Ng Pediatrics 2008 Porto-hepatic shunts presenting with proteinuria and Focal Nodular Hyperplasia
FNH
At diagnosis
Angiography and embolization with vascular plugs
6 years after closure Effectiveness of CPSS closure on encephalopathy
Cognitive improvement
Normalization of blood ammonia level
18 months after closure Disappearance of abnormal hypersignal of the globus pallidus on T1 brain MRI sequences Effectiveness of CPSS closure on hepatopulmonary and porto-pulmonary syndrome
• Regression of pulmonary arterio-venous shunts
• Stabilisation and exceptional regression of arterial pulmonary pressure
dyspnea on exertion no dyspnea hypoxaemia + cyanosis no cyanosis Surgical closure of a conspicuous portacaval shunt
Tc 99 labeled albumin Skull/lungs = 4.5 % macroaggregates Skull/lungs = 0.29 % scintigram 9,5 yo 12 yo Is closure of CPSS always necessary?
10 days 2 years
Spontaneous closure of porto-hepatic shunts is expected
6/10 in our experience on 50 patients <1 y, Median age: 4 mo Management of CPSS What about end to side shunts (Abernethy1)?
Because of the theoretical risk of portal hypertension, in the litterature:
Abstention X Liver transplantation
What about closure of those shunts ? How things changed 12 yo girl. Bicycle accident. Abdominal pain Abdominal US
End to side Porto-caval shunt (Abernethy 1) Huge hepatocellular adenoma
adenoma resection impossible Liver transplantation? Pretherapeutic evaluation Phlebography with occlusion test
End to side communication No portal vein going to the liver between the portal vein and during occlusion test !!! the IVC.
Options would be survey of the tumor and liver transplantation if necessary Management of CPSS What about end to side shunts (Abernethy1)?
In this case of end to side porto-caval shunt (Abernethy 1 malformation) with supposed congenital absence of portal vein (CAPV), most authors propose simple observation and liver transplantation.
Banding of the shunt was performed by Pr Frederic Gauthier in 2008….. Follow-up after banding….
D3 post-op 4 month post-op
Precocious hepatopetal portal flow in liver parenchyma showing portal reperfusion of the liver Evolution after treatment
2012 2007 Post-banding 5 y. after closure Why and when is angiography with occlusion test necessary?
Prenatal diagnosis abnormal abdominal vessel (1995) confirmed postnatally with US and considered as an end-to-side communication between the portal vein (PV) and the IVC without intrahepatic portal branch visible on conventionnal imaging (Abernethy 1 malformation) No complication at birth Progressive hepatic encephalopathy with mental retardation
Spl V
SHUNT PV
IVC Patient’s anatomy according to CT and US SMV IVC Portography during occlusion test Portal pressure during occlusion: 22 mm Hg
IVC IHPB Spl V PV SMV PcV
SMV PcV
catheter catheter Occlusion balloon
Ectopic portal vein =Side to side malformation = Abernethy 2 Portography during occlusion test Portal pressure during occlusion: 22 mm Hg
IHPB
PV
PcV SMV
Ectopic portal vein =Side to side malformation = Abernethy 2
One step closure: surgical or IR Why and when is angiography with occlusion test necessary?
If the MPV and the intrahepatic portal branches are not visible
To assess the presence of an extremely hypoplastic and/or ectopic MPV
To mesure portal pressure during occlusion : 1 or 2 step closure procedure Occlusion test with ectopic portal veins
Porto-systemic encephalopathy in a 8 yo girl Severe hepatopulmonary syndrome in a 6 yo girl with cardiac malformation. presenting with Heterotaxia, polysplenia Aspect of end-to-side porto-caval shunt on CT syndrome,cardiac malformation. and US
CPSS consisting in an abnormal vessel between Ectopic portal vein arising from the the spleno-mesenteric confluence and the right superior mesenteric vein (SMV) renal vein. Occlusion test shows an ectopic MPV visible after occlusion of the shunt arising from ths SMV by inflating a balloon in the IVC and injecting iodine in the SMV Occlusion with Amplatzer Plug 2 Surgical closure Making a decision on how and who will close the CPSS Whenever possible endoluminal closure will be performed Surgical closure of the CPSS is indicated in patients considered unsuitable for endoluminal closure
Long enough and not too large Too short to put a device = OK for radiological closure Radiology or surgery… = Surgical closure Closure of a patent Ductus venosus 15 yo boy fortuitously discovered, liver nodules and low prothrombin time
+ anticoagulation WHEN should neonatal closure be recommended?
After prenatal or neonatal diagnosis of … … porto-hepatic fistula : NO … extra-hepatic shunt before main portal vein : YES ! WHY ?
Prenatal diagnosis of umbilico-porto-systemic shunt with an abnormal vessel between the splenomesenteric confluence and the left renal vein at 12 do, progressive thrombosis of the MPV and intrahepatic portal branches related to flow void by CPSS CT-scan at day 8 Angiography,occlusion test and embolization day 13
Occlusion of the abnormal Occlusion test shows The CPSS consists in a large vessel using a vascular Plug 2 abnormal intrahepatic portal veins Vessel between the confluence of the mesenteric and splenic veins and the left renal vein Peroperative US-Doppler showing the immediat restoration of the portal flow to the liver Benefits of neonatal closure Prenatal and postnatal normal aspects
X
Neonatal occlusion of the shunt
No treatment prenatal postnatal Progressive hypoplasia of MPV and portal branches Conclusion
• Closure of most CPSS possible
•IR is essential for: •Precise diagnosis: Occlusion test +++ in extrahepatic CPSS +++ •Embolization of the shunt in selected cases
•Few complications after closure: •Thrombosis = prophylactic anticoagulation •Portal hypertension = 2 step procedure if necessary
•Resolution of most complications after closure, except advanced pulmonary arterial hypertension
•Effectiveness on prevention of complications advocates prophylactic closure
For any question