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inflammationresultsinvesselmuralnecrosiswithsubsequentfibrosis,
thrombosis,andmicroaneurysmformation.Myocarditishasalsobeen
reported.337Thismaybethecauseoftheleftventricularsystolicdysfunction
andmitralvalveregurgitationthatarefrequentlyseen.338Supportivecare
coupledwithimmunomodulatorytherapyarethemainstaysoftreatment.

SystemicLupusErythematosus
Systemiclupuserythematosusisageneralized,progressive,multisystem
connectivetissuediseaseofunknownetiology.Duringchildhood,themeanage
ofonsetis12years.Itveryrarelypresentsbeforetheageof5years.339The
cutaneous,osteoarticular,renal,hematopoietic,centralnervous,pulmonary,and
gastrointestinalsystemsarecommonlyaffected.Cardiacinvolvementisalso
veryfrequentandcanbepresentatanytimeduringthecourseofthedisease.
Themostcommonmanifestationsarepericarditis,myocarditis,Libman-Sacks
endocarditisleadingtovalvarstenosisand/orincompetence,disturbancesof
rhythm,coronaryarterydisease,andsystemicandpulmonaryhypertension.Any
ofthesecanleadtoCHF,whichcarriesapoorprognosis.340Depositionof
immunecomplexesandcomplementactivationhaveamajorpathogenicrolein
theselesions.Pericarditisisthemostcommoncardiacmanifestation.Upto
three-quartersofpatientshaveechocardiographicevidenceofpericardial
disease.Clinicalinvolvementisseeninone-third,generallyasacutepericarditis,
whichmayhavearecurrentnature.Serouseffusionsarecommon,and
complementlevelsinthefluidareverylow.Chronicconstrictivepericarditisand
tamponadearethankfullyrare.
Evidenceofmyocarditiscanbeseeninabouthalfthepatientsatpostmortem,
butclinicalinvolvementisgenerallysilent.Dyspneaisthemostcommon
symptom.Thepresenceofagalloprhythm,cardiomegalyonthechest
radiograph,andventriculardilationontheechocardiogramcompletetheclinical
picture.TheECGisnonspecific.T-waveinversion,ventricularprematurebeats,
andfirst-degreeatrioventricularblockmayallbepresent.Inapproximatelyhalf
thepatients,therearenonbacterialverrucousvegetationsonthecardiacvalves,

so-calledLibman-Sacksendocarditis.Theseareclumpsoffibrinfrom0.1to4
mmindiameterwithlymphocytesandplasmacellinfiltratesthataremost
frequentlyseenonthemitraland/oraorticvalves.Fibroustissue,whichmay
laterbecomecalcified,appearsduringtheprocessofhealing,sometimesleading
tovalvardysfunction.Mitralandaorticincompetenceandlessfrequently


stenosisarethemostcommonlesions.Echocardiographicevaluationisauseful
noninvasivemethodfortheassessmentofvalvardysfunction.Doppler
examinationshouldincreasethesensitivityofearlydetectionofvalvedisease.
ThepresenceofLibman-Sacksvegetationspredisposestobacterialendocarditis,
althoughperipheralembolismisrare.Thecoronaryarteriescanbeaffectedbyan
acuteinflammatoryarteriticprocessor,lessfrequentlyinchildhood,by
atherosclerosis.Coronaryarteritiscanleadtoaneurysmaldilationofthearteries,
thrombosis,andmyocardialinfarction.Thisisanuncommoncauseofdeath.
Disturbancesofrhythmandconductionarecommon.Atrialfibrillationorflutter
maybeseenduringacutepericarditis,whereasventricularectopicbeatsand
first-degreeatrioventricularblockareseeninthecourseofactivemyocarditis.
Completeheartblockmayresultfromvasculitisofsmallvessels,andfibrosisof
theconductionsystemhasbeendescribedinadults.Systemichypertensionis
veryfrequent.Itisgenerallycausedbylupusnephritisorbyprolongedsteroid
therapy.
Therevisedcriteriaforthediagnosisofsystemiclupuserythematosusrequire
thepresenceofatleastfourofthefollowing:malarrash;discoidrash;
photosensitivity;oralulcers;arthritis,pleuritis,orpericarditis;renaldisorders
suchasproteinuriaorcellularcasts;neurologicdisorderssuchasseizuresor
psychosis;hematologicdisorderssuchashemolyticanemia,leucopenia,
lymphopenia,orthrombocytopenia;immunologicdisorderssuchaspositive
lupuserythematosuscellpreparations,antibodiesagainstdouble-strandedDNA
(anti-dsDNA)orSmithprotein(anti-Sm),orantinuclearantibodies.341A

revisiontotheimmunologiccriteriawasmadein1997toinclude
antiphospholipidandanticardiolipinantibodies.342
Thelong-termprognosisisvariable.Boysseemtohaveamoresevereformof
thediseasethangirls.Themostcommoncausesofdeatharerenalinvolvement
andsepsis.Deathfromcardiaclesionsisnotfrequent,butaggressivetherapyis
warrantedwhenmyocarditisisevident,asitscoursecanbefulminantand
lethal.343Corticosteroidsarethebasisoftreatment.Immunosuppressivetherapy
withazathioprineorcyclophosphamidecanbeusedasasupplementwhenthere
isnoresponsetohighdosesofsteroidsorwhenthereissevererenalorcentral
nervoussysteminvolvement.Apartfromthissystemicformoftherapy,the
managementofspecificlesionsdoesnotdifferfromthatofthepatientwithout
lupuserythematosus.
Neonatallupuserythematosusisararevarietyofthesystemicdisease.Itis
frequentlyassociatedwithmaternallupusandcharacterizedbycutaneouslesions


withorwithoutcongenitalcompleteheartblockandsystemicmanifestations.344
ProlongationoftheQTinterval,sinusbradycardia,lower-gradeheartblock,and
dilatedcardiomyopathycanalsooccur.Skinlesionsdevelopwithinthefirst3
monthsoflifeandoccurmainlyinareasexposedtolight,thussuggesting
photosensitivity.Theyconsistoferythematousmacules,papules,orplaquesthat
mayexhibitthecharacteristicsofdiscoidlupus,specificallyscaling,atrophy,
follicularplugging,andtelangiectasia.Later,theyhaveresidualhyper-or
hypopigmentationandresolvecompletelywithin12monthswithminimal
atrophyorscarring.Systemicmanifestations—includinghepatosplenomegaly,
anemia,leukopenia,andthrombocytopenia—occurwithinthefirstweeksoflife
andtendtobeself-limiting.Specifictreatmentisrarelynecessary.Congenital
completeheartblock,unlikethecutaneousandsystemicmanifestations,is
irreversible.Thereisahighcorrelationwiththepresenceofanti-SSA/Ro
antibodiesinmaternalserum,thesehavingbeendemonstratedinoverthreequartersofpatients.345Approximately5%ofbabiesborntomotherswiththese

antibodieswilldevelopcompleteheartblock.346Theautoantibodiesare
frequentlyfoundinpatientswithsystemiclupuserythematosusandSjögren
syndrome,buttheyarerarelyencounteredinthegeneralpopulation.AntiSSA/Rooranti-SSB/Laantibodiesareimmunoglobulin-Gformsthatreachthe
fetusbytransplacentaltransfer.Theycanbedetectedinbabieswithcongenital
completeheartblockbefore3monthsofagebutnotaftertheyare6monthsold.
Theunderlyingmechanismproducingheartblockisnotclear,butitproduces
fibrosisoftheatrialcomponentoftheatrioventricularconductionaxis.Pacing
mayberequiredinapproximatelytwo-thirdsofsuchpatients.347Completeheart
blockinthesubsequentpregnanciesofmotherswithlupusisuncommon,
affectingapproximatelyone-sixth.Treatment,bothforthepreventionofheart
blockandasatreatmentforevidentevolvingheartblock,hascenteredon
fluorinatedsteroids.Thisremainscontroversialandhasyettobeproven
beneficial.348Morerecentevidencesuggeststhatwhenusedthroughout
pregnancythereisaroleforhydroxychloroquineinpreventingautoimmune
congenitalcompleteheartblock.349