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Introduction
Intrahepatic arterioportal fistula (APF) is a rare condi-tion in children. APF may be congenital, post-traumatic,iatrogenic (transhepatic intervention or biopsy) or relatedto ruptured hepatic artery aneurysms. To date, only 17cases of congenital intrahepatic APF have been reportedin the literature [1, 2, 3, 4]. Most occurred in infants, theoldest patient being a 3-year-old boy reported by Marc-hand et al. [1] This report concerns an unusual presen-tation with the incidental diagnosis in a 13-year-old boy,and in whom the feeding artery was rather large andnecessitated the use of atypical embolisation material.
Case report
While being assessed for an acute attack of bronchial asthma, a 13-year-old boy was found to have a murmur in the epigastrium by the
general practitioner. He had no abdominal symptoms, no historyof trauma and no previous surgical interventions. Clinical exam-ination was unremarkable with normal growth and absence ofhepatosplenomegaly. Liver function tests were normal. ColourDoppler US showed an aneurysmal left portal vein (PV) fed by alarge arterial branch and reversed blood flow in the left PV. Thespleen was enlarged (12.5 cm). Gadolinium-enhanced MRA con-firmed a solitary APF connecting the left hepatic artery and the leftbranch of the PV, with no other vascular or parenchymal anoma-lies.
Because the child was asymptomatic, discussion about thera-peutic alternatives took place and the choice was for electiveangiography with possible embolisation. While awaiting the angi-ogram the child presented acutely with haematemesis and melena.This settled with conservative management. Endoscopy, angiog-raphy and radiological intervention were performed under the samegeneral anaesthetic session. Endoscopy showed grade III varicesand portal hypertensive gastropathy. Angiography was performedthrough a right femoral approach. A selective hepatic arteryinjection confirmed this was a typical congenital APF with a singlefeeding artery, a large arteriovenous fistula, and a large venousaneurysmal pouch developed lateral to the left PV (Fig. 1a–c). Asdescribed in other cases, this high-flow fistula resulted in reversed
CASE REPORTPediatr Radiol (2003) 33: 20–23DOI 10.1007/s00247-002-0764-x
Nagappan Kumar
Jean de Ville de Goyet
Khalid Sharif
Patrick McKiernan
Philip John
Congenital, solitary, large, intrahepaticarterioportal fistula in a child: managementand review of the literature
Received: 7 March 2002Accepted: 11 April 2002Published online: 1 August 2002� Springer-Verlag 2002
N. Kumar Æ J. de Ville de Goyet (&)K. Sharif Æ P. McKiernanLiver Unit, Birmingham Children’sHospital NHS Trust, Steelhouse Lane,Birmingham B4 6NH, UKE-mail: [email protected].: +44-121-333-8252Fax: +44-121-333-8251
P. JohnDepartment of Radiology, BirminghamChildren’s Hospital NHS Trust,Birmingham, UK
Abstract Congenital intrahepaticarterioportal fistula (APF) is a rarecondition. In most cases, the symp-toms and complications developduring infancy. We report here theincidental finding of a large andsolitary congenital APF in a 13-year-old boy, with subsequent relatedclinical complications. At angiogra-phy, an APF connecting the lefthepatic artery and the left branch ofthe portal vein (PV) was demon-strated with reversed flow in the leftand main PV. The fistula wassuccessfully occluded, in a singleembolisation session, using anAmplatzer occlusion device. Thiswas associated with immediate
restoration of normal hepatopetalflow in the PV and followed by res-olution of the clinical signs of portalhypertension. This patient is theoldest child with congenital intrahe-patic APF to be reported. Weemphasise the interest of using alarge device (Amplatzer) to occludea solitary large APF in a single ses-sion and, more importantly, to avoidother possible complications relatedto embolisation.
Keywords Congenital vascularmalformation Æ Liver Æ Arterioportalfistula Æ Portal hypertension ÆRadiological intervention
PV flow and in retrograde filling of portosystemic collaterals.Complete reversal of the flow in the PV trunk was confirmed at theportal phase of the selective superior mesenteric angiogram: therewas no filling of the portal vein beyond the confluence of the su-perior mesenteric vein and the splenic vein (Fig. 1d). Only a smallvenous collateral was seen feeding towards the liver (caudate lobe)(Fig. 1d).
As the APF was relatively large in diameter (4.5 mm; Fig. 2a)and with high flow, it was felt that the use of conventional steelcoils for embolisation might be complicated by the coils movingtowards the portal system, intra- or extrahepatically, with subse-quent thrombosis. Therefore, an Amplatzer occlusion device wasused to occlude the APF (Fig. 2b, c). Immediately after insertion ofthe device, flow through the APF ceased; repeat injection into thesuperior mesenteric artery confirmed hepatopetal flow in the PVwith adequate filling of the right and left intrahepatic portal radi-cals (Fig. 2d). Furthermore, all branches of the hepatic artery hadbeen preserved (Fig. 2c).
Three-month follow-up oesophagoscopy showed deflated gradeI varix with normal stomach and duodenum. Doppler US 3 and6 months later showed that the occlusion device was stable in itsinitial position and that PV flow was still hepatopetal. There was noresidual flow in the embolised fistula. The common hepatic arteryand branches remained patent with reduced (compared to pre-operative) flow velocities. The spleen was noticed to reduce in sizewith time (11 cm at 6 months post-intervention).
Discussion
Although they may be seen in other sites, congenitalAPF is commonly intrahepatic. Clinical manifestationsusually occur below 1 year of age and are related toprogression of portal hypertension (gastrointestinalbleeding, ascites, failure to thrive, diarrhoea and
malabsorption). To our knowledge, this patient is theoldest child ever reported in the literature with intrahe-patic APF of congenital type. It is quite likely that theAPF had been gradually increasing in size with age andindeed was picked up incidentally. Portal hypertensionpredated the diagnosis, as suggested by splenomegalyon the first US and further progression during the sub-sequent months with gastrointestinal bleeding. Sincebleeding was manageable conservatively and occurred5 days before the day electively booked for intervention,the child was managed electively, as planned. We believethis observation confirms that APF must be consideredfor treatment, even in the absence of previous compli-cation at diagnosis.
APF usually has a single feeding artery, which dif-ferentiates it from an arteriovenous malformation withmultiple feeding vessels [1]. The former characteristicthus increases the chance of successful occlusion of APFvia interventional radiological procedures, therebyavoiding the need for surgery even in small children.This was shown by Lamireau et al. [3], who reportedsuccessful embolisation of congenital APF in infants andat a single attempt using 3-mm flower-type steel coils.However, in many series more than one interventionwas necessary to achieve occlusion. Vauthey et al. [2]reviewed 88 cases from the literature, with APF fromvarious aetiologies and at various ages and found thatradiological interventions were successful in 42% of thecases and that surgery contributed to the treatment inevery second case. Surgical procedures undertaken
Fig. 1a–d Pre-interventionselective hepatic artery (HA)angiography showing a large,solitary arterioportal fistulafeeding from the left HA(a) towards the left portal veinthrough a large venous aneu-rysm (b). Flow in the left andmain PV is reversed (c), as con-firmed by the portal phase ofthe superior mesenteric arteryangiogram showing absence ofportal perfusion towards theliver (d). (Portal flow directionshown by small arrows)
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included partial hepatectomy or even portosystemicshunt.
The advantage of the interventional radiologicalprocedure over surgery is a shorter hospital stay, de-creased pain and lower morbidity. Also, it allows forbetter targeting of the feeding artery, thus increasingefficacy and selectivity of the embolisation; the surgicalapproach is usually more ‘central’ and ‘blind’. The‘single intervention’ success rate depends on the exper-tise of the team and the choice of appropriate material.However, multiple interventions may be necessary toachieve successful occlusion in case of multiple feedingarteries or secondary recruitment of new collaterals withtime. In these recurrent cases, non-surgical treatment ispreferable, of course, because the success rate is nothigher with surgery.
A major risk of embolisation of a large APF is, asshown by previous reports, PV thrombosis followingthe procedure. This complication may be related todirectly locating the material at the wrong site, or tothe material moving from the original site to the portalsystem because of high flow in the fistula. In thesecases, the development of a portal cavernoma was thenassociated with persistence of chronic portal hyperten-sion and related clinical problems. Because of the large
diameter of the feeding artery in the reported patient,the risk of a coil embolising through the APF to theportal system was real and not acceptable. As alter-native material, a 6/4-mm Amplatzer device was suc-cessfully used. The latter device is commonly used atour institution to occlude patent ductus arteriosus. Itallowed occlusion of the APF at a single session andpreserved the segmental arterial supply to the liver. Asconfirmation of the successful treatment, the portalflow redirected immediately with no residual filling ofthe gastric veins at angiography, and this result per-sisted with time, as shown by follow-up Doppler US.Also, and more importantly, success was confirmed bysubsequent regression of clinical signs of portal hy-pertension (absence of recurrent bleeding in the absenceof sclerotherapy, spontaneous regression of the hyper-tensive gastropathy and oesophageal varices, anddecrease of spleen size).
Overall, the experience gained with this case confirmsthe role of interventional radiology for the managementof congenital APF. The use of an Amplatzer device toocclude a large feeding artery may seem anecdotal, but itstresses the importance of choosing the appropriatematerial and avoiding complications.
Fig. 2 a Radiological interven-tion on a large (4.6-mm diam-eter) APF. Positioning of anAmplatzer device (large arrow)(b, c) resulted in complete,single step, obliteration of thefistula. Normal portal venoushaemodynamics was restoredimmediately, as shown byportal blood flowing towardsthe liver at the portal phase ofsuperior mesenteric angiogramafter intervention (d)
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References
1. Marchand V, Uflacker R, Baker SS, et al(1999) Congenital hepatic arterioportalfistula in a 3-year-old child. J PediatrGastroenterol Nutr 28:435–441
2. Vauthey JN, Tomczak RJ, Helmberger T,et al (1997) The arterioportal fistulasyndrome: clinicopathologic features,diagnosis and therapy.Gastroenterology113:1390–1401
3. Lamireau T, Chateil JF, Petit P, et al(1999) Successful embolization of con-genital intrahepatic arterioportal fistulain two infants. J Pediatr GastroenterolNutr 29:211–214
4. Raghuram L, Korah IP, Jaya VV, et al(2001) Coil embolization of a solitarycongenital intrahepatic hepatoportalfistula. Abdom Imaging 26:194–196
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