Andersons pediatric cardiology 1304
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ExteriorizationoftheHeart(Ectopia
Cordis)
ItismaintainedthattheallegedlyinitialdescriptionoftetralogyofFallot
providedbySteno1wasalsothefirstreportofanextrathoracicheart.2
Rashkind,3however,arguedthatsuchmalformationswerealmostcertainly
recognizedlongbefore1671,providingevidencethattheywererecordedinthe
writingsoftheancientBabylonians.Heartspositionedinpart,orcompletely,out
ofthethoraxfortunatelyremainveryrare.Untilrecently,withrelativelyfew
exceptions,suchoccurrencesproveduniformlyfatal.Althoughthelesionis
usuallytermed“ectopia,”therearedeficienciesinsuchusage,sincetheGreek
word“ektopos”simplymeansawayfromaplace.4Itfollowsthataheartfound
intherightchestofanotherwisenormalpersonwouldbeectopic.Ectopia,
nonetheless,ismoreusuallyusedtoaccountforaheartlocatedinpart,or
completely,outsidethethoraciccavity.Theheart,withorwithoutitspericardial
covering,iscompletelyexteriorizedthroughadeficiencyoftheskinin
approximatelythreequartersofthereportedcases.5Intheremainingcases,the
heartisseenpulsatingthroughtheintactskin,withthisvariantalsoknownas
partialectopiacordis.
Theheartshavetraditionallybeengroupedaccordingtotheirlocation,with
initialdescriptionsofcervical,thoracic,andabdominalsubsets.6–8Itis
convenient,nonetheless,toaddacombinedthoracoabdominalvariant,along
withacombinedthoracocervicalgroup.4Casesencounteredmorerecently
continuetofallwithinthesegroupings.
Whentheheartisfoundintheneck,thesternumisusuallyintact.This
arrangementreflectsaretentionofthenormalinitialsiteofcardiac
development.5Exampleshavebeenrecordedwhenaninfantsurvivedforafew
hourswithacervicalheart,whileonepatientwiththisanomalywasreputedto
havesurvivedtoadultlife.9Thislatterexample,however,wouldprobablybe
betterplacedinthecombinedthoracocervicalgroup.Thosedismissingthe
existenceofthecervicalsubsethavesuggestedtheneedtodistinguishbetweena
clefttothesternumandanextrathoracicheart.2Congenitalabsenceorcleftingof
thesternumisalwaysassociatedwithabnormalpositioningoftheheartand
arterialtrunkstosomeextent,albeitwiththeoverlyingskinandpericardium
remainingintact(Fig.49.1).Rarely,prematurefusionofthemanubriosternal
jointandthesternalsegmentsmayproduceahighcarinatedeformityofthe
chest,alongwithashortsternum.Thisistheso-calledCurrarino-Silverman
syndrome,whichisfrequentlyassociatedwithcongenitalheartdisease.10
Irrespectiveofsuchniceties,heartsofthecervicaltypearebyfartherarest.
Thereisalsoaquestionmarkoverthegroupwiththeheartallegedlycontained
withintheabdomen.Alargeseriesofsuchheartswascombinedtoproducethis
grouping,6butreexaminationoftheoriginalreportssuggestedthat,inallbut
one,partoftheheartwasretainedwithinthechest,thusmakingitbetterto
groupthemwithinthecombinedabdominothoracicsubset.3Thereforethe
majorityofallcaseseitherprotrudefromthechestorextendthrougha
diaphragmaticdefect.Alloccupyamidlinedeficiencyofthebodywall,lying
partlyinthechestandpartlyeitherwithintheabdomenortheneck.Inthecases
exteriorizedfromthechest,theheartsareusuallycoveredbyneitherskinnor
pericardium(Fig.49.2).Inthepast,variousmeanshadbeenemployedto
providethelackofmoistureensuingfromtheabsenceofapericardialcavity.
Thus,quaintaccountssurvivefromthe18thcentury,describingexteriorized
heartsbeingcoveredwithacontraptionmadeofpliableosiersandlinen,and
anointedwithwineandmeltedbutter.11Heartswerealsocoveredwitha
pasteboardcone,withoilusedfortheanointingagent,orelsesalinesponges.7
Irrespectiveofthemethodemployed,mostpatientssurvivedforonlyamatterof
hoursordays.
FIG.49.1 Computedtomographicreconstructionshowingtheabnormal
locationoftheheartinthesettingoftheabsenceofthesternum.Thereisa
cervicalaorticarch.C,Clavicle;PT,pulmonarytrunk.
