Sudden Cardiac Death in Young Athletes.pdf

Sudden Cardiac Death in Young Athelets Presentation by Professor Sherif Mokhtar , President of the Egyotuan College of Critical Care Physicians

1. M. SherifMokhtar, MD
Critical Care Medicine Department
Cairo University

2. ➢AmajorpublichealthproblembothattheUS
andworldwide.
➢ItisestimatedthateachyearintheUS400,000-
460,000personsdieofunexpectedSCDin
EmergencyDepartmentsorbeforereachinga
hospital.
➢Definedasunexpecteddeathwithinonehour
fromtheonsetofsymptoms.

3. ➢Eventsarewitnessedinonlytwo-thirdsof
cases.
➢Thecardiacrhythmatclinicalpresentationis
unknowninmanycases.
➢ItisnotpossibletorestrictthedefinitionofSCA
todocumentedcasesofVF.
➢ThedurationofsymptomspriortoSCAis
unknowninapproximatelyone-thirdofcases.
(Siscovick, 1993)

4. ►Twotothreetimesmorecommoninmenthanin
women.
►Six-toten-foldinthepresenceofclinically
recognizedheartdisease,
►Increaseswithage.
►Mayoccurfromnoncardiaccauses(e.g.,trauma,
pulmonaryembolism).
(Zheng et al., 2001; Kannelet al., 1998)
(Myerburg, 1997; Weveret al., 2004)

5. The incidence of SCD among
competitive athletes is actually quite low: 1/per
50,000 versus 1/10000 per general population.
(Maronet al., 1986; 1996; Van Camp et al., 1995).

6. hypertrophic ;
36
Anomalous;
17
Myocarditis;
6
Mitral valve;
4
Arrhythmogenic
RVC;
4
Aortic stenosis;
3
Tunneled CA;
3
Coronary
Atherosclerosis;
3
Ion
channelopathies;
3
Idiopathic Dilated
Cardiomyopathy;
2
Ruptured Aortic
Aneurysm;
2
Other CHD;
2
Effects of Underlying HD

7. I.CHANNELOPATHIES &ELECTRICALCAUSES
II.MYOPATHIES&CONCEALED STRUCTURAL HD
III.ACQUIREDCARDIACDISORDERS

8. Myerburg, 1997
Wever et al., 2004
I.CHANNELOPATHIES &ELECTRCIALCAUSES
➢ThelongQ-Tsyndromes
➢BRUGADASyndrome
➢CatecholaminergicPolymorphicVT
➢EarlyRepolarizationSyndrome
➢ShortQTSyndrome
➢WPWSyndrome
➢IdiopathicVF

9. Myerburg, 1997
Weveret al., 2004
II.MYOPATHIES&CONCEALED STRUCTURAL HD
➢ArrhythmogenicRVDysplasia
➢HypertrophicCardiomyopathy
➢Myocarditis
➢CoronarySpasm
➢CongenitalCoronaryAbnormalities
➢Aorticstenosis
➢Marfansyndrome

10. III.ACQUIREDCARDIACDISORDERS
➢CommotioCordis
➢PerformanceEnhancingDrugs
➢PrematureCoronaryDisease
Myerburg, 1997
Weveret al., 2004

11. Myerburg, 1997
Weveret al., 2004
➢InthetrulynormalheartSCD,isanuncommon
occurrence.
➢Themajoritydonotactuallyhave"normal"hearts,
butourdiagnostictoolslimitidentificationof
structuralorfunctionalderangement.

12. Myerburg, 1997
Wever et al., 2004
I.CHANNELOPATHIES &ELECTRCIALCAUSES
➢ThelongQ-Tsyndromes
➢BRUGADASyndrome
➢CatecholaminergicPolymorphicVT
➢EarlyRepolarizationSyndrome
➢ShortQTSyndrome
➢WPWSyndrome
➢IdiopathicVF

14. ➢Agroupofhereditaryionchannelopathieswitha
prevalenceof1in2,000to5,000inthegeneral
population.
➢TheincidenceofSCDinathletesduetoLQTSwas
2%(U.S.registry).
➢Maybemisdiagnosedasepilepsy
Maron, et al., 2009
…………………………………….The Silent Killers

15. ShouldbeconsideredwhentheQTcinterval:
•Exceeds440msinmalesor460msinfemales,
•Intheabsenceofmedicationscapableofcausing
acquiredQTintervalprolongation.
Corrado, et al. ,2010
…………………………………….The Silent Killers

16. •Morethan95%ofcasesrepresentabnormalitiesinthe
RectifierPotassiumChannels(IKr,IKs)orInward
SodiumchannelscorrespondingtoLQTtypes1to3.
•Thelifetimeriskofcardiacarrestisintheorderof3%to
5%,withcardiacarrestastheinitialmanifestation.
Goldenberg , et al., 2008, Kaufman et al., 2008
…………………………………….The Silent Killers

17. Gene-specifictriggersofsymptoms:
▪Swimming-orexercise-relatedeventsinLQT1,
▪AuditoryoremotionaltriggersinLQT2,and
▪Resting-orsleep-relatedeventsinLQT3.
Concernsshouldalsoberaisedwhensyncopeor
cardiacarrestoccursinthesettingofnewmedication.
Schwartz et al., 2001
…………………………………….The Silent Killers

18. 1.Testingusuallyinvolvesexerciseprotocolsor
infusionofsympathomimeticagents.
2.Epinephrine(adrenaline)testingisnowin
widespreaduse.
3.OthernovelprotocolshaveincludedI.V
erythromycin,facialimmersion,andadenosine
boluses.
Jeyaraj, et al., 2008 & Viskin, et al., 2006, Yoshinaga, et al., 1999
Shimizu, et al., 2004, Vyas, et al., 2006
Wong JA, et al., 2010
…………………………………….The Silent Killers

19. Myerburg, 1997
Wever et al., 2004
I.CHANNELOPATHIES &ELECTRCIALCAUSES
➢ThelongQ-Tsyndromes
➢BRUGADASyndrome
➢CatecholaminergicPolymorphicVT
➢EarlyRepolarizationSyndrome
➢ShortQTSyndrome
➢WPWSyndrome
➢IdiopathicVF

20. •FirstidentifiedbyMartinietalin1989,Subsequently
describedbytheBrugadabrothersin1992
•AnabnormalpersistentSTelevationwithRBBB
patterninasmallcohortofcardiacarrestsurvivors
withstructurallynormalhearts.
•Anautosomaldominantsodiumchannelopathywith
anincidenceof1in2,000to5,000.
•Usualpresentationinthefourthdecadeoflifedespitethe
presenceoftheunderlyingdefect(s)atbirth.
Martini, 1989, Brugada, 1992
Crouse 2009
Antzelevitchet al 2003
…………………………………….The Silent Killers

21. Brugadasyndromemayrepresenteithera:
▪Functionalabnormalityintheelectricalactivityoftheheart
i.e(primaryelectricaldisease,channelopathy)or
▪Anearlysubclinicalmanifestationofarrhythmogenicright
ventriculardysplasia(ARVD).
Additionalfeaturesinclude:
▪UnmaskingofthecharacteristicECGchangesby
sodiumchannel-blockingdrugssuchasajmaline,
flecainide,andprocainamide.
Electrophysiological Basis and Genetics
…………………………………….The Silent Killers

22. Variation in the precordial lead ST and T waves in a
patient with Brugadasyndrome.

23. Prognosis and Therapy
•A7.7%annualeventratewasnotedincardiacarrestsurvivors.
•ICDtherapyisthereforestronglyrecommended in
spontaneoustype1Brugadapatientsofmalesexwhocontinue
tobesymptomatic.
•Avoidanceofsodiumchannel–blockingdrugsandpromptfever
controlareimportant.
•ThereisnomedicaltherapyofprovenbenefitinBrugadasyndrome,
•althoughquinidinehasbeenreportedtobeofuseinlimitedstudies.
Belhassen, 2004
…………………………………….The Silent Killers

24. Myerburg, 1997
Wever et al., 2004
I.CHANNELOPATHIES &ELECTRCIALCAUSES
➢ThelongQ-Tsyndromes
➢BRUGADASyndrome
➢CatecholaminergicPolymorphicVT
➢EarlyRepolarizationSyndrome
➢ShortQTSyndrome
➢WPWSyndrome
➢IdiopathicVF

25. ➢Arareandmalignantcondition,
➢Typicallypresentinginlatechildhoodandearly
adolescencewithexertionalsyncopeorcardiacarrest.
➢Itstrueprevalenceisunknown,butithasbeenreported
in13%ofcardiacarrestswithoutheartdisease.
Leenhardt, 1995
Krahn2009, Liu, 2008
…………………………………….The Silent Killers

26. ➢Typically,thebaselineelectrocardiogramisunremarkable,
➢Exercisestresstestingmayprovokemultifocalventricular
prematurebeatsorVTwithbeattobeat180°alternating
QRSaxis(BidirectionalVT).
Syncopeorcardiacarrestisinducedbystressfuleventsor
exertion,whichcaninclude:
➢Sportingevents,On-stagepresentations,Arguments,and
Examinations,whicharecommoninthepresentingage
range.
…………………………………….The Silent Killers

27. •ArrhythmiasoccurintheabsenceofQTprolongation.
•Theunderlyingmechanismisattributedto
IntracellularCalciumOverload(failedreuptakeof
calciumintothesarcolemicreticulum),
•TypicallyrelatedtomutationsintheRyR2gene,
leadingtocalciumleakattheleveloftheRyanodine
Receptor.
Priori 2001
…………………………………….The Silent Killers

28. Myerburg, 1997
Wever et al., 2004
I.CHANNELOPATHIES &ELECTRCIALCAUSES
➢ThelongQ-Tsyndromes
➢BRUGADASyndrome
➢CatecholaminergicPolymorphicVT
➢EarlyRepolarizationSyndrome
➢ShortQTSyndrome
➢WPWSyndrome
➢IdiopathicVF

29. •Firstreportedinthe1930s,
•HaslongbeenbelievedtobeanormalECGvariant
andbenignentity,(alsotermedjuvenileSTpattern?)
•Identifiedin31%ofpatientswithapparentidiopathic
VF.
•TheestimatedprevalenceofERSincardiacarrest
withoutstructuralheartdiseasewas8%.
Shipley 1936
Haissaguerre2008
Krahn2009
…………………………………….The Silent Killers

30. ➢ThemechanismofERSisincompletelyunderstood,and
➢DebateexistsregardingwhetherECGchangesrepresent
LateDepolarizationsorEarlyRepolarizations.
➢ECGimprovementwithisoproterenolandtypicalabsence
oflatepotentialsonsignal-averagedECGmakeit
unlikelytobeadepolarizationabnormality.
HaissaguerreM, 2016
…………………………………….The Silent Killers

32. ➢NogeneticbasisforERS
➢Therearecurrentlynoprovocationteststoinduce
oramplifySTchangesinERSortoprovoke
arrhythmias.
➢Littleisknownofthemannerinwhichtoriskstratify
patientswithERS.
➢?useofICDsforsecondaryprevention.
…………………………………….The Silent Killers

33. Myerburg, 1997
Wever et al., 2004
I.CHANNELOPATHIES &ELECTRCIALCAUSES
➢ThelongQ-Tsyndromes
➢BRUGADASyndrome
➢CatecholaminergicPolymorphicVT
➢EarlyRepolarizationSyndrome
➢ShortQTSyndrome
➢WPWSyndrome
➢IdiopathicVF

34. ➢TherecognitionthatQTshorteningwaslinkedtocardiac
arrestwasfirstpublishedin1993
➢Asacauseofcardiacarrest,itappearsextremelyrare.
➢Variedpresentationage(between4and80years)
➢Approximatelyonethirdpresentingwithcardiacarrest,
onethirdwithsyncope,andonethirdwithpalpitations.
Krahnet al., 2009
…………………………………….The Silent Killers

35. ➢ThediagnosisofSQTSshouldbeconsideredinany
symptomaticpatientwithQTc<360msandin
➢AsymptomaticpatientswithQTc<320ms.
➢TallorpeakedTwavesarecommon,andadepressedPR
intervalissometimesseen.
…………………………………….The Silent Killers

36. ➢Theunderlyingpathophysiologyisrelatedtogain-of-
functionmutationsintheinwardrectifierpotassium
channels,shorteningtheactionpotentialduration.(SQT1
throughSQT3),and
➢Loss-of-functionL-typecalciumchannelmutations
comprisetheremainingSQT4andSQT5.
…………………………………….The Silent Killers

37. Electrocardiogram of a patient with short QT syndrome.
Observe the tall peaked T waves.

38. PrognosisandTherapy
•ThetrueSQTS,(withassociatedsymptoms),confersapredicted
50%chanceofcardiacarrestbytheageof40years.
•ICDimplantationiscurrentlytheonlytherapyprovento
reducecardiacarrest,althoughhighratesofinappropriate
therapyduetopeakedT-waveoversensingarereported.
GiustettoC, 2006
…………………………………….The Silent Killers

39. Myerburg, 1997
Wever et al., 2004
I.CHANNELOPATHIES &ELECTRCIALCAUSES
➢ThelongQ-Tsyndromes
➢BRUGADASyndrome
➢CatecholaminergicPolymorphicVT
➢EarlyRepolarizationSyndrome
➢ShortQTSyndrome
➢WPWSyndrome
➢IdiopathicVF

40. •Theprevalenceofpreexcitationinathletesissimilartothat
inthegeneralpopulation(0.1%to0.3%).
•IfAFdevelopsthereisariskofSCDfromVFsecondaryto
rapidanterogradeconductionviatheaccessorypathway.
•DeterminingtheelectricalpropertiesoftheAPiscrucialfor
establishingtheriskofSCD.
•CurativecatheterablationoftheAPinadultspermitsreturn
tocompetitivesportsafter3months.
Heidbuchel, et al., 2006
…………………………………….The Silent Killers

42. Myerburg, 1997
Wever et al., 2004
I.CHANNELOPATHIES &ELECTRCIALCAUSES
➢ThelongQ-Tsyndromes
➢BRUGADASyndrome
➢CatecholaminergicPolymorphicVT
➢EarlyRepolarizationSyndrome
➢ShortQTSyndrome
➢WPWSyndrome
➢IdiopathicVF

43. •ThediagnosisofidiopathicVFismadewhenno
othercauseisfound.
•Despitesystematicscreeningtests,approximately
halfofcardiacarrestpatientswithoutovertheart
diseaseremainundiagnosedoridiopathic.
TheCanadianCASPER
TheCardiacArrestSurvivorsWithPreservedEjectionFractionRegistry
(CASPER)
…………………………………….The Silent Killers

44. ➢Clearly,thereareanumberofcontendersfora
diagnosisinthiscohort,including:
▪Coronaryspasm,
▪Occultsarcoidosis,and
▪Latentformsofalloftheknowncardiacarrest–
relatedconditionsdescribed,particularlyearly
repolarizationandSQTSbecausetheyremain
withoutvalidatedprovocationtests.
…………………………………….The Silent Killers

45. Serialtelemetryexcerptsfrom
apatientwithunexplained
cardiacarrestandsmall
troponin rise after
resuscitation(top).Coronary
angiography demonstrated
minorluminalirregularities
withoutsignificantstenosis.
Subsequent repeat
angiographywithergonovine
challengeprovokedprofound
coronary spasm with
ventricularirritability(bottom).

46. Myerburg, 1997
Weveret al., 2004
II.MYOPATHIES&CONCEALED STRUCTURAL HD
➢ArrhythmogenicRVDysplasia
➢HypertrophicCardiomyopathy
➢Myocarditis
➢CoronarySpasm
➢CongenitalCoronaryAbnormalities
➢Aorticstenosis
➢Marfansyndrome

47. ➢Areportedprevalenceof1/1,000inthegeneralpopulation.
➢Aninheritedmyocardialdiseasecausedbymutationsin
genesencodingcardiacDesmosomalProteins.
➢Focalmyocarditiswithsubsequenthealingleadsto
progressivefibrofattyreplacementofthemyocardiumanda
propensitytoVT/VF.
➢MacroscopicappearancesincludeRVdilation,dysfunction,and
aneurysmformation.
Basso, et al., 2009
…………………………………….The Silent Killers

48. •Exerciseexacerbatespathophysiologicalchanges
•A5-foldhigherriskofSCDduringcompetitivesports
comparedwithsedentaryactivity.Corradoet al., 1997, 2003
Reliesonmeetingthe2010ARVCTaskForcecriteria:
•Symptoms,Familyhistory,Resting/ambulatoryECG
changes,Echocardiography,CardiacMagnetic
Resonance Imaging,andMyocardialtissue
characterization.
Marcus et al., 2010
…………………………………….The Silent Killers

49. •Previouscardiacarrest,
•Unexplainedsyncope,
•VTwithhemodynamiccompromiseand
•ExtensivestructuraldiseaseincludingLVinvolvement
ShouldpromptconsiderationofprophylacticICDimplantation.
Garratt et al., 2010, Corrado, et al., 2003
…………………………………….The Silent Killers

50. ➢Typicallycausedbyviralinfections(e.g.,
CoxsackieB)accountsforupto7%ofSCDin
athletes.
➢Unlessfulminant,myocarditisdoesnotusually
producesignificantventriculardilatationorsystolic
impairmentonechocardiography.
Eckart, et al., 2004
…………………………………….The Silent Killers

51. ➢Maypresentprimarilywitharrhythmiawithout
overtevidenceofLVdysfunction.
➢DelayedgadoliniumenhancementonMRI,
providesahighlysensitivetoolfordiagnosis.
Friedrich et al., 1998
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52. ➢ReportedlycauseSCDin12%to33%ofathletes.
➢ThemostcommonanomaliesimplicatedareLCAoriginsin
therightsinusofValsalvaandRCAoriginsintheleftsinusof
Valsalva.
➢DiagnosisusingECG,isnotoriouslydifficultbecauseaffected
individualsrarelyrevealfeaturesofinducibleischemia
➢Cardiacmagneticresonanceangiographyandcomputed
tomographycoronaryangiographyarethegoldstandardimaging
modalities.
Angelini. 2007, Prakken, et al., 2010
…………………………………….The Silent Killers

53. Other structuralcardiacabnormalities
associatedwithSCDinclude:
➢Marfansyndrome
➢Aorticdissection/rupturetypicallyinthecontextof
Marfansyndrome,
➢Mitralvalveprolapse(MVP),and
➢Aorticstenosis.
…………………………………….The Silent Killers

54. •Acollagendisordercausedbymutationsinthe
geneencodingFibrillin,
•Inheritedasanautosomaldominanttraitwitha
prevalenceof1in5,000.
•Itaccountsforapproximately3%ofexercise-
relatedSCDinyoungathletes.
Marfansyndrome
…………………………………….The Silent Killers

55. •Marfanpatientsshouldbeprohibitedfrom
isometricorisotonicexerciseofmoderateto
highintensity.
•Individualswithanenlargedaorticroot(40mm)
shouldreceiveabeta-blockertohelpretard
aorticdilation. Maronet al., 2005
Marfansyndrome
…………………………………….The Silent Killers

56. Aorticstenosisduetoacongenitalbicuspid
aorticvalveisararebutrecognizedcauseofSCDin
youngathletesthatcanbeidentifiedthroughbasic
screeningeffortsinvolvingcardiovascularphysical
examination.
…………………………………….The Silent Killers

57. Competitivesportshouldbeprecluded
whenMVPisassociatedwithmoderateto
severemitralregurgitation,severechestpain,
exertionalsyncope,documentationofVT,a
longQTinterval,orMarfansyndrome.
Maronet al., 2005
…………………………………….The Silent Killers

58. III.ACQUIREDCARDIACDISORDERS
➢CommotioCordis
➢PerformanceEnhancingDrugs
➢PrematureCoronaryDisease
Myerburg, 1997
Weveret al., 2004

59. ➢MostoftenoccursinYoungAthleteswhohavebeen
struckintheprecordiumwithaprojectileobjectsuch
asabaseball,hockeypuck,orfist.
➢Mostlyduringorganizedorrecreationalsporting
activities,anduringroutinedailyactivities.
➢Usuallyaccidental,althoughsomehaveresultedin
criminalliability
(Maronet al., 2002)

60. •ArapidincreaseinLVpressure,Appearstoactivate
ionchannelsviamechanoelectriccoupling,
•ResultinginthegenerationofanInwardCurrent,
augmentationofRepolarization,andNonuniform
myocardialactivation.
•SubsequentprematureVentricularDepolarizations
triggerVFandSCD.
Link, et al., 1998
CommotioCordis
…………………………………….The Silent Killers

61. III.ACQUIREDCARDIACDISORDERS
➢CommotioCordis
➢PerformanceEnhancingDrugs
➢PrematureCoronaryDisease
Myerburg, 1997
Weveret al., 2004

62. •Anabolic-androgenicsteroids,
•Stimulantssuchasephedrine,and
•Nonsteroidalagentssuchasrecombinanthuman
erythropoietin
HavebeenassociatedwithSCD.
➢Anabolicandrogenicsteroidshavebeenshownto
changelipoproteinmetabolismleadingtopremature
atherosclerosisandmyocardialinfarction.
➢Bothanabolic-androgenicsteroidandephedrineusemay
resultincardiomyopathyandventriculararrhythmias.
Performance-Enhancing Drugs
…………………………………….The Silent Killers

63. PhysiologicalLVHishomogeneous and
associatedwithchamberenlargementandnormal
indexesofdiastolicfunction.
Incontrast,individualswithHCMoftenshow
asymmetricalpatternsofLVH,smallchambersize,and
impaireddiastolicfunction.
End-diastolicLVdimensions55mmarecommon
intrainedathletesbutarerareinHCMinwhichtheLV
cavitysizeisusually45mm.
Athlete’s Heart versus HCM

64. III.ACQUIREDCARDIACDISORDERS
➢CommotioCordis
➢PerformanceEnhancingDrugs
➢PrematureCoronaryDisease
Myerburg, 1997
Weveret al., 2004

65. InlargeseriesfromItalyandtheUnited
States,prematureatheroscleroticcoronaryartery
diseaseaccountedfor2%to3%ofSCDinyoung
athletes.
Corrado, et al., 2006
Maronet al., 2009
Premature Coronary Artery Disease
…………………………………….The Silent Killers

66. Minor Cardiac Abnormalities Not
Associated With SCD

67. 1.AdirectlinkbetweenMitralValveProlapseand
SCDhasnotbeenestablishedunlessthereis:
▪Valveredundancyorthickening,
▪AfamilyhistoryofSCD,
▪Significantmitralregurgitation,
▪QTintervalprolongation,or
▪ST-Twaveschanges
Minor Cardiac Abnormalities not associated with SCD

68. 2.AFinpatientslessthan70yearsofageandAFin
theabsenceofventricularpreexcitationor
hyperthyroidismisassociatedwithanincreaseintotal
mortality,butnotSCD.
3.IsolatedVentricularPrematureBeatsare
associatedwithanincreasedriskofsubsequentSCD
onlyinpatientswithstructuralHDorwithriskfactors
forCHD.
Viskin& Belhassanm1990
Minor Cardiac Abnormalities not associated with SCD

69. Theexactmechanismofcollapseinanindividual
patientisoftenimpossibletoestablishsincepatientswhodie
suddenlyareseldomundercloseobservation.
Asaresult,themechanismcanonlybeinferred,
baseduponinformationobtainedaftertheprocesshasbeen
initiated.
Conclusions

70. However,therehavebeenmanycasesinwhichthe
initiatingeventhasbeenwitnessedorrecorded.Thishas
usuallyoccurredinpatients:
▪Beingcontinuallymonitoredinthecoronarycareunitor
▪Witha24-hourambulatoryECGrecordingdeviceor
▪Animplantablecardioverter-defibrillator(ICD).
Ventriculartachycardia(VT)orventricularfibrillation
(VF)accountforthemajorityofepisodes.
However,abradyarrhythmiaisresponsibleforsomecasesof
SCD.
Conclusions