Br Heart J 1990;63:311-3

Dilated and contracted forms of primaryendocardial fibroelastosis: a single fetal diseasewith two stages of development

A M Carceller, E Maroto, J-C Fouron

AbstractLeft ventricular endocardial fibro-elastosis was diagnosed by echocardio-graphic scanning in a fetus at 20 weeks'gestation. Repeated prenatal examina-tion over the next 20 weeks' gestationshowed the development of the left ven-tricle from a chamber with a dilatedcavity to a small cavity with a very thickwall. These findings were confirmed atnecropsy and by the absence of othermorphological anomalies.The contracted form of primary

fibroelastosis in the fetus must havefollowed an insult that prevented anyfurther increase in the size of the leftventricular cavity.

The classification of primary endocardialfibroelastosis as either dilated or contracteddepends on the size of the left ventricularcavity.' So far only a few cases ofthe contractedform have been reported2 and these wereexclusively in neonates.3 There are only a fewreports of the detection of primary endocardialfibroelastosis in fetuses by echocardiography.45In these cases, however, the dilated form of thedisease only was reported in three infants at 28,35, and 36 weeks' gestation respectively duringa single evaluation. We used similar echo-cardiographic techniques to detect primaryendocardial fibroelastosis in a fetus and followthe course of the disease over 20 weeks.

whereas there was a considerable increase inpulmonary blood flow.The mother was given digoxin immediately.

After 24 hours, she was put on a maintenancedose of 0 5 mg of digoxin. After a few days, thepericardial effusion disappeared but left ven-tricular contractility remained poor. Twomonths later, the fetal left atrium seemed to beslightly dilated and the interatrial septumbulged towards the right atrium (fig 2A). At 39weeks' gestation, echocardiographic evalua-tions showed a decrease in the diameter of theleft ventricular cavity which was associatedwith a thickening of the free wall with a veryechogenic endocardium (fig 2B). At 40 weeks'gestation, a male infant weighing 3-25 kg wasdelivered vaginally. Apgar scores were 8 and 9to 1 and 5 minutes respectively. Tests for viralinfections were negative. Despite intensivecardiac support, the infant died seven daysafter birth.

Necropsy showed a thickened left ven-tricular wall with a small cavity lined by a whitelayer that was consistent with the diagnosis ofendocardial fibroelastosis (fig 2C). The diag-nosis was confirmed by microscopical examin-ation (Weigert and trichrome stains). Themitral orifice was smaller than normal (dia-meter 0-6 cm) but the mital valve leaflets wereintact. The aortic valve was bicuspid with thinmobile cusps but the aortic root was only 0 4cm in diameter. The ductus arteriosus and theforamen ovale were patent.

Fetal Cardiology Unit,Section of PediatricCardiology,University ofMontreal, Sainte-Justine Hospital,Montreal, CanadaAM CarcellerE MarotoJ-C FouronCorrespondence toDr J-C Fouron, Service ofCardiology, Sainte-JustineHospital, 3175 Chemin C6teSte-Catherine, Montreal,Quebec H3T 1 C5, Canada.

Case reportA 28 year old primigravida, without risk factorsfor congenital heart disease, was transferred toour fetal cardiology unit when a four chamberview ofthe fetal heart was found to be abnormalduring routine obstetric ultrasonography at20 weeks' gestation. Fetal echocardiographyshowed a dilated and hypotonic left ventriclewith a very bright echogenic line over theendocardium which suggested fibroelastosis.The right ventricle was hyperdynamic.Hydrops fetalis was noted (ascites, pericardialand pleural effusions) (fig 1A). The mitral andthe aortic valves were normally formed butwith poor mobility. Pulsed Doppler assessmentof intracardiac flows showed a very low peakvelocity and velocity time-integrals throughthe mitral and aortic valves (fig lB and C),

DiscussionDespite the obvious difference between thedilated and contracted forms of primary endo-cardial fibroelastosis we think that it is wrong toassume that there are two distinct diseases withdifferent aetiologies. Our patient shows that ina fetus primary endocardial fibroelastosis canstart as the dilated stage of the disease andprogress to the contracted stage.Though we did not seek histological

evidence of fibroelastosis during gestation, theechocardiographic image of the endocardiumwas similar to the image at birth when there washistological confirmation of fibroelastosis.Because the fetal ventricles work in parallel,there are two possible courses after the onset ofleft ventricular failure early in gestation: eitherthe right ventricle efficiently assumes almost

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Carceller, Maroto, Fouron

Figure) (A)Echocardiographic fourchamber view of the heartat 20 weeks'gestation. Theleft ventricle (LV) wasdilated and a brightechogenic line was visibleover the endocardium (E).Pericardialfluid (F) wasalso seen. RV, rightventricle. (B) Bloodflowvelocity profiles throughthe mitral and (C) aorticvalves. Left ventricularfilling occurred chieflyduring early diastole.

the entire circulatory load and fetal survival ispossible or the right ventricle fails to cope withthe new task and the fetus dies. The onset ofendocardial fibroelastosis after birth alsocauses considerable left ventricular failure andbecause the ventricles now work in seriessurvival depends upon the level ofperformanceof both ventricles.We first saw our patient at 20 weeks' gesta-

tion at an early stage in the development offibroelastasis. The echocardiographic imageswere compatible with endocardial fibroelas-tosis, the left ventricle was hypotonic, dilated,and hydrops fetalis also indicated the failure ofthe right ventricle. Only rapid treatment of themother with digoxin prevented the death of the.

fetus; and evidence of fluid retention disap-peared. The ensuing events were predictable-according to the dynamic concept of organicdevelopment6-the very low blood flow intothe left ventricle stopped the growth not only ofthe left ventricle but also the inflow andoutflow valves and the ascending aorta. Atbirth, after 40 weeks' gestation the dimensionsof the left-sided structures were those of a 28week old fetus. These results support thespeculation made by Neill and Ursell7 that justas the size of the foramen ovale can be used as amarker for intra-atrial flow in utero, so the sizeof the ascending aorta can be used as anindicator of intrauterine flow through theaortic valve. We believe that the contracted

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Dilated and contractedforms ofprimary endocardialfibroelastosis: a single fetal disease with two stages of development

Figure2 (A)Anechocardiographic view ofthe interatrial septum (S)bulging paradoxicallytowards the right atriumat 28 weeks' gestation. Thefree wall of the leftventricle (LV) was thickand the endocardium wasechogenic. (B) Fourchamber view at 39 weeks'gestation showing a leftventricular cavity (L V)with a smaller diameter.RV, right ventricle. (C)The heart showing a smallleft ventricular cavity withdense white endocardiallining. Thefree wall wasvery thick.

form of primary fibroelastasis evolves from adilated form of the disease in utero.

We thank Miss Susan P Drblik for her adviceon this paper.1 Edwards JE. Congenital malformations of the heart and

great vessels. In: Gould SE, ed. Pathology of the heart.Springfield, Illinois: Charles C Thomas, 1953:420.

2 Ursell PC, Neill CA, Anderson RH, Siew YH, Becker AE,Gerlis LM. Endocardial fibroelastosis and hypoplasia ofthe left ventricle in neonates without significant aortic

stenosis. Br Heart J 1984;51:492-7.3 Blieden LC, Schneeweiss A, Deutsch V, Neufeld HN.

Contracted form of endocardial fibroelastisis: angio-graphic diagnosis and necropsy confirmation. PediatrCardiol 1983;4:281-3.

4 Veille JC, Sivakoof M. Fetal echocardiographic signs ofcongenital endocardial fibroelastosis. Obstet Gynecol 1988;72:219-22.

5 Bovicelli L, Picchio FM, Pilu G, et al. Prenatal diagnosis ofendocardial fibroelastosis. Prenat Diagn 1984;4:67-72.

6 Rudolph AM, Heymann MA, Spitznas U. Hemodynamicconsiderations in the development of narrowing of theaorta. Am J Cardiol 1972;30:514-25.

7 Neill CA, Ursell P. Endocardial fibroelastosis and left hearthypoplasia revisited. Int J Cardiol 1984;5:547-50.

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