Andersons pediatric cardiology 1759
Bạn đang xem bản rút gọn của tài liệu. Xem và tải ngay bản đầy đủ của tài liệu tại đây (60.48 KB, 3 trang )
device,11%haddied,and3%hadrecovered,foranoverallpositiveoutcomeof
89%.TheauthorsfoundthattheHVADsysteminthepediatricpopulationwas
associatedwithlowmortalityinthemajorityofpatientssupportedfor1year.
Thisiscomparabletoadultdata,althoughtemporaryrightVADsupportand
pumpexchangeremainriskfactorsforpooroutcomesinthepediatric
population.Althoughveryencouraging,thedatasetdidnotallowananalysisof
themorbidities,whichwillneedtobestudied.
Priorto2012,onlyonepediatricVADprogramhadanintracorporealCF
device.Now,5yearslater,everyprogramusesintracorporealCFdevices
routinely.Withrecentimprovements,CFVADsarenowplacedmoreoftenthat
EXCORsinpediatrics,accordingtomostrecentPedimacsreport.44Thisshift
towardCFVADsinpediatricsfollowstheprevioustrendinadults.
FutureDevices
TheNationalHeart,Lung,andBloodInstitutestartedthePediatricCirculatory
SupportProgramfordevelopmentofnovelMCSdevicesforinfantsandchildren
in2004.Carefulselectionledtomorethan$20millionofsupportgrantedtofive
contractors:PediaFlowpediatricVAD(UniversityofPittsburgh),PediPump
(ClevelandClinic),pediatriccardiopulmonaryassistsystem(Ension,Inc.),
PediatricJarvik2000(JarvikHeart,Inc.),andpediatricVAD(PennsylvaniaState
University).45ThiswasfollowedwithfundingforthePumpsforKids,Infants,
andNeonates(PumpKIN)preclinicalprogramin2010tofurtherdevelopfour
MCSdevices.Fourcontractstotaling$23.6millionwereallottedfor
continuationofthreeofthePediatricCirculatorySupportProgramdevices
(pediatriccardiopulmonaryassistsystem,Jarvik2000,andPediaFlow),aswell
asthepediatricpump-lung(PediPL)(Levitronix,LLC).Oftheinitialdevices
funded,onlytheJarvik2015isstillundergoingtesting.Itisanintracorporeal,
axialCFVADnolargerthananAAbattery,designedtosupportpediatric
patientsbetween8and20kg.Afteraseriesofchangestotheoriginaldevice,
mostrecentlytodecreasehemolysis,46thedevicehaspassedanimalsstudies,47
andarandomizedtrialthatbeganin2017isenrolling88patientstobecompared
1:1versustheEXCOR.
OthercompaniesarelookingtodevelopnewtypesofMCSforchildrenas
well.VADovationsisaprivatecompanythatiscurrentlytestingintracorporeal
CFdevicesinanimals,focusingspecificallyonhemocompatibility,including
preservingvonWillebrandfactorfunctiontoreducenonsurgicalbleedingand
reducingplateletactivationtolimitthromboembolicevents.Thesepromising
animalstudieshavethepotentialforuseasarightVADinadultsandacuterightsidedsupportfortheFontancirculation.Beingonly8mmindiameterand50
mmlong(sizeofAAbattery),thedevicecaneasilysitinlinewithablood
conduit.Althoughtheseandothersystemsareyearsfromwidespreadusein
children,itreflectstheincreasedinterestandfundinggoingtowarddeveloping
long-termsolutionsforpediatricheartfailureandCHD.
SpecialPopulations
BivadVersusLVADSupport
AsseenintheadultVADexperience,thenumberofBiVADsalwaysdecreases
asdecision-makingmatures,whichcorrelateswithanincreaseinsurvivaland
decreaseinmorbidity.Thisisdocumentedbymultipleinstitutionalseriesandby
examinationofthePedimacsorINTERMACSregistries.StillerandHetzerhave
writtenregardingtheiruseoftheBerlinHeartEXCORVADattheBerlinHeart
Institute.Despiteessentiallysimilarpatientpopulationsovertime,theyhave
decreasedthenumberofBiVADs,whichhascontributedtoimprovedoutcomes.
ImprovedsurvivalofLVADsoverBiVADswasalsodemonstratedinthe
pediatricfieldbytheearlyNorthAmericanexperiencewiththeEXCOR(88%
vs.64%6-monthsurvival).32Afollow-upstudyofthiscohortspecifically
attemptedtoidentifythosepatientgroupswhowouldbenefitfromBiVAD
supportoverLVADsupportbutunfortunatelywereunabletoidentifyanypatient
cohort.48However,thisshouldnotbetakentomeanthattherearenopatients
whobenefitfromBiVADsupportbecausethelackofidentifyingacohortwas
surelysecondarytopatientnumbers.Mostexpertsagreetherearepatientswho
benefitfromBiVADsupportoverLVADsupport,likelythosewithprimary
unremittingarrhythmiaburden,certainseverebiventricularrestrictivedisease,or
certaincongenitalpatientswithbiventricularfailure.
NotonlycanimproveddecisionmakingdecreasetheneedforrightVAD
support,butperioperativetechniqueshavealsoledtodecreasedneedforBiVAD
support.Rightventricularstresscanbereducedbylimitingcirculatingvolume,
reducingmyocardialedemaandcytokineoverloadwithultrafiltration,limiting
bleedingandthuspostoperativetransfusions,andsupportingtherightheart
aggressivelyintheimmediatepostimplantperiod(e.g.,inhalednitricoxide,
milrinone,and/orepinephrine).Managingseptalshiftandminimizingtricuspid
insufficiencyviatransesophagealechocardiographywhenseparatingfrom
cardiopulmonarybypassandclosingthesternumisimportant.Theincreasing
useofintracorporealCFdevicesinthepediatricpopulationunderlineshowthe
maturationofthefieldhasprogressedfrom40%ofpatientsreceivingBiVAD
supporttolessthan20%presently.Ultimately,asmallportionofpatients(likely
<10%)willandshouldbebettersupportedwithBiVADscomparedwithan
LVAD,butthiswilllikelybedeterminedbyetiologyofheartfailureasopposed
