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Page 1: Sudden Cardiac Arrest · ¨ Sudden cardiac arrest is a rarity among the young, especially athletes. According to Cleveland Clinic, sudden cardiac death kills 1 in 100, 000 to 1 in

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Sudden Cardiac Arrest

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¨ https://www.youtube.com/watch?v=CWFyxn0qDEU

¨ https://www.youtube.com/watch?v=RYZ4daFwMa8

¨ 1. Understand ventricular arrhythmias malignant vs Benign

¨ 2. Understand the causes of malignant ventricular arrhythmias and how to detect them

¨ 4. Understand pharmacological management for ventricular

arrhythmias

¨ 5. Understand Electrophysiology options for the treatment of ventricular arrhythmias

¨ 6. Understand when is anticoagulation appropriate

¨ Sudden cardiac arrest is a rarity among the young, especially athletes. According to Cleveland Clinic, sudden cardiac death kills 1 in 100, 000 to 1 in 300,000, athletes under 35 years, more often males.

¨ Worldwide sudden cardiac death (SCD) is about 25% of the 17 million deaths every year. Cardiovascular diseases are responsible for these deaths. Men have a higher incidence of SDC than women, and it increases with age due to the prevalence of CAD in older adults.

¨ U.S. Olympic volleyball player Flo Hyman (1986), college basketball player Hank Gathers (1990), professional basketball players Pete Maravich (1988), Reggie Lewis (1993),

¨ Professional soccer players; Piermario Morosini (Italy, 2012), Antunion Puerta (Seville, Spain 2007), Marc “Marco” Vivien Foe (Cameroon, 2003), and Miklos Feher (Hungary, 2004)

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¨ Many of us know the difference between cardiac arrest and heart attacks. As we all know, cardiac arrest is the result of the cardiac electrical system malfunction, which leads to no contractions and no perfusion, which impairs the brain, lungs, kidneys, and liver function after a few minutes and death occurs.

¨ Cardiac arrest may occur suddenly or within an hour if symptoms are present. Symptoms can consist of shortness of breath, chest pain, chest pressure, dizziness, or fainting. Signs consist of collapse, no pulse, loss of consciousness and no breathing.

A heart attack or myocardial infarction occurs coronary artery stenosis is more than 80% occluded which prevents oxygen-rich blood from reaching the cardiac muscle. If no intervention is done within minutes to open the vessel the cardiac muscle begins to die. During this process the person begins to experience symptoms which may be immediate and intense. Many times the symptoms begin slowly and may persist for hours, days or weeks before a myocardial infarction (MI) occurs. During an MI, most of the time the heart continues to contract and patients may remain conscious. Unlike with sudden cardiac arrest, the heart usually does not stop beating during a heart attack. The heart attack symptoms in women can be different from men.

¨ These two cardiac conditions are linked. Sudden cardiac arrest (SCA) can occur with a myocardial infarction or during recovery. The fact that a person may have an MI, will increase the risk of SCA. Most MIs do not lead to sudden cardiac arrest. However, if SCA does occur it usually is associated with an MI, especially if the patient is older (>60 years old).

¨ According to the European Society of Cardiology 2015 guidelines, cardiac diseases associated with Sudden cardiac death (SCD) differ in young vs. older individuals, over 40 years. In the young there is a predominance of channelopathies and cardiomyopathies, myocarditis and substance abuse, while in older populations, chronic degenerative diseases predominate (Coronary artery disease, valvular heart diseases and Heart Failure). In younger persons, the cause of SCD may be elusive even after autopsy, because conditions such as inherited channelopathies or drug-induced arrhythmias that are devoid of structural abnormalities are epidemiologically relevant in this age group.

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¨ Today’s presentation will be discussing the conditions or diseases that lead to lethal ventricular arrhythmia such as Ventricular tachycardia, Ventricular Fibrillation and Torsade de Pointe.

¨ There are many causes and ACLS has their own list but we will be concentrating on Hypertrophic Cardiomyopathy, Arrhythmogenic right ventricular dysplasia (ARVD), Marfan syndrome, Prolong QT interval, other ventricular arrhythmia causes, and Ventricular fibrillation

¨ Benign conditions consist of Ventricular premature beats, ventricular tachycardia in normal structured heart

¨ CollegebasketballplayerHankGathers(1990),ProfessionalbasketballplayerReggieLewis(1993),HungariansoccerplayerMiklosFeher (2004)

¨ Itisaheterogeneousdisordercharacterizedbyvariabledegreesofleftventricularhypertrophy,normalorsmallleftventricularcavitysizeandhyperdynamicsystolicfunction.

¨ Fewpeoplewithpredominantlyinterventricularseptalhypertrophyinassociationwithanteriormotionofthemitralleafletsandsubvalvularleftventricularoutflowtractobstruction,whichleadstoaconditiondenotedashypertrophicobstructivecardiomyopathy.Thisconditionaffects1in500individualsinthegeneralpopulation.

(HCM) is the leading cause of SCD in young people including athletes (a)

¨ ThereisavariantofHCM thatisfoundintheelderlyoften-femalepatientswithHTN,Thereareover50differentmutationsaffectingthemyosinheavychainsandmyosinlightchains,tropomyosinandtronins.

¨ HCM ischaracterizedbythedynamicLVoutflowtractobstruction(LVOFT)anddiastolicdysfunction.

¨ ThedegreeofLVOFT obstructionmayvarybelowtheaorticvalve;thiscanlaterpresentitselfbyanarrowedseptalhypertrophy.

¨ Theclinicalmanifestationsalsovary.Somepatientsareasymptomaticformanyyears.

¨ Otherspresentwithlife-threateningarrhythmiasorsuddencardiacdeath.Themostfrequentsymptomsisdyspneaonexertion.

¨ ThisissecondarytodiastolicdysfunctionandelevationinLVfillingpressures.Thisisaprogressivedisease.Syncopecanresultsfromseverobstructionfo theLVOFT andconcomitantreducedcardiacoutputaswellasarrhythmias.Iftherightventricleisinvolvedinthemyopathyprocess,symptomsofright-sidedheartfailuremayalsobepresent.

¨ Patientswithsignificantoutflowtractobstructionmaytypicallypresentwithaharsh,crescendo-decrescendosystolicmurmurheartbestatleftsternalborderthatisintensifiedbymaneuversthatdecreaseleftventricularvolume.AnS4 ispresentwithincreasedventricularstiffness

¨ Anechocardiogramisrecommended,whichwillhelpindiagnosingpatientwithsuspectedHCM

¨ TheEKGwilldemonstrateanincreasedQRS voltagesecondarytoLeftVentricularHypertrophy(LVH).ProminentabnormalQwavesarefrequentlypresentintheinferiorandlateralleadsandreflectdepolarizationofthehypertrophiedseptum.NegativeTwavesinprecordialleadsandlateralleads,anddeepSwaveinprecordialleads.

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• (ARVD)isaninherited heartdiseasewhichisaprogressiveconditionoftherightventricularcardiacmusclewhichleadstoventriculartachycardia,HFandSCD.Thehistologicalhallmarkofthediseaseisreplacementofcardiomyocytesbyadiposeandfibroustissue.

• Clinically,arrhythmogenic rightventricularcardiomyopathy(ARVC)isdefinedbystructuralandfunctionalabnormalitiesoftherightventricle,butLVinvolvementoccursin50%ofpatients.InmostcasesARVC isinheritedasanautosomaldominantgenetictraitcausedbymutationsingenesencodingfordesmosomalproteins.

• ARVC hasanestimatedprevalenceof1in1000to1in5000ofthegeneralpopulationandisanimportantcauseofSCDinathletesandyoungadults.ARVC isanimportantcauseofventriculararrhythmiasinchildrenandyoungadults.Itisseenpredominantlyinmales,and30–50%ofcaseshaveafamilialdistribution

¨ Clinicalmanifestationsincludepalpitations,syncope,VTandSCD,usuallydevelopbetweenthesecondandfourthdecadeoflife.Asthediseaseprogresses,itcanresultintorightorbiventricularheartfailure.

¨ ARVD canbefoundinassociationwith diffusepalmoplantarkeratoderma,and woollyhair.Itisanautosomalrecessiveconditioncalled Naxosdisease,becausethisgeneticabnormalitycanalsoaffecttheintegrityofthesuperficiallayersoftheskinmostexposedtopressurestress.

¨ Uptotwo-thirdsofpatientshaveventriculararrhythmiasonECG,holtermonitoringandexercisetesting,stresstestingorcardiopulmonaryexercisetesting.TheseventriculararrhythmiasareusuallyofRVorigin(i.e.showaleftbundlebranchmorphology),buttheQRS axisduringVTusuallydiffersfromtheQRS axisinRVOT,andmanypatientshavemultipleQRS morphologies.

¨ Medicaltreatmentisnotoptimal,howeverSotalolwhichisanantiarrhythmicmedicationhasshowntoreducefrequentventricularectopyorNon-sustainedventriculararrhythmias.However,amiodaronehasshowntobesuperiorinpreventingventriculararrhythmiasvsBBtherapy.

¨ Electrophysiologystudywithvoltagemappingidentifiesregionsoffibro-fattyreplacementandtoguidecatheterablationofventriculararrhythmias.AcutesuppressionofVTismoreoftensuccessfulinpatientspresentingwithasingleoronlyafewselecteddominantVTmorphologiesandepicardialablationmayincreasesuccessrates.Asneitheranti-arrhythmicdrugsnorcatheterablationprovidessufficientprotectionagainstSCD,ablationshouldbeusedtoreducethefrequencyofarrhythmiaepisodesratherthantoimproveprognosis.

¨ Automaticimplantablecardiacdefibrillatorsisthemostappropriatetherapyforsustainedmonomorphicventriculartachycardia.

¨ Competitiveexercisemayexacerbatelethalventriculararrhythmias.

Epsilon waves

¨ CardiacAmyloidosisconsistsoflight-chainamyloidosiswhichiscausedbydepositionofmonoclonallightchainsandhereditarytransthyretin-associatedamyloidosis,inwhichnormal(wild-type)ormutanttransthyretinisdepositedinthemyocardium.

¨ Cardiacamyloidosishasbeenassociatedwithaverypoorprognosis,usuallyamediansurvivalof,1yearaftertheonsetofheartfailuresymptoms.Uptohalfofallpatientswithcardiacamyloidosisdiesuddenly.Deathisattributedtoventriculararrhythmias,howevercasereportsrevealasuccessfulterminationofsustainedventriculararrhythmiaswiththeaidofanimplantablecardiacdefibrillator(ICD).

¨ Holtermonitoring,homemonitoringanddevicemonitoringrevealsthatventriculararrhythmiasarepresentin25%ofpatientswithcardiacamyloidosis,buttheirpresencedoesnotseemtopredictSCD.ICDs shouldbeconsideredinpatientswithlight-chainamyloidosisorhereditarytransthyretin-associatedamyloidosis.Thereareinsufficientdatatoproviderecommendationsonprimaryprophylaxis.

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¨ Itistheleastcommoncardiomyopathiesandiscausedbynumberofgeneticandacquireddisorders.Inadultsthecommoncauseisamyloidosisfollowedbymutationsinsarcomeric proteingenesandmetabolicdisorders.Patientswithrestrictivecardiomyopathypresentwithsignsandsymptomsofbiventricularheartfailureanddiagnosedbycharacteristicfeaturesonnon-invasivecardiacimagingandcardiaccatheterization.Restrictivecardiomyopathyisassociatedwithpoorlong-termprognosis.

¨ Inchildren,theriskofsuddendeathmaybehigher,particularlyinthosewithECGevidenceofmyocardialischemia.Thetreatmentofrestrictivecardiomyopathyismostlypalliative.

¨ HFsymptomsaretreatedwithdiureticsandheartratecontroltooptimizeLVfilling.Anticoagulationshouldbeusedinallpatientswithatrialfibrillation.ThereisnoprospectivedataonprophylacticimplantationofICDs inrestrictivecardiomyopathy,soforpatientswithsymptomaticsustainedventriculararhythmias,indicationsforICDshouldbesimilartoothercardiomyopathies,takingintoaccounttheshort-termprognosisrelatedtoHF.

¨ Marfansyndromeisanautosomaldominant,connectivetissuedisorderwhichaffectsmultiplesystems.Itischaracterizedbylongbones,ortallandthin,longarms,fingers,toes,flexiblejointsandscoliosis.Themostseriousconditionsdealswithmitralvalveprolapseanddilatationoftheaorticroot.

¨ In1896,AntoineBernard-JeanMarfandescribedthesyndromeinayoungpatientwithpeculiarlylongandthindigits,elongatedlimbs,andcongenitalcontracturesofmultiplejoints.

¨ Overtime,contracturearachnodactyly,aconnectivetissuedisorder,wasdescribedin1968.Fiftyyearslater,marfan’sfeaturesinothersystemsweredescribedinpatientswiththin,elongatedlimbsincludingmitralvalvediseasein1912;dislocationoftheocularlensin1914;rupturedaorticaneurysmin1918;aorticrootdilatationanddissectionin1943.

¨ Marfansyndromeisclearlyoneofthemorecommon,potentiallylethalMendelianconditionswithanestimatedprevalenceof1caseper3000to5000individuals.

¨ CardiovascularconditionsarethepredominantfeatureofMarfansyndromewhichincludesproximalascendingaorticdilatation,dilatationoftheproximalmainpulmonaryartery,thickeningandprolapseofeitherorbothatrioventricularvalves,andmitralannularcalcification.

Dissection lesion¨ ThereareEKGabnormalitiesinMarfansyndromepatientswhichincludeprolongedatrioventricularconductiontime(firstdegreeorsecondAVblocks),andST-segmentabnormalities.Ventricularrepolarizationabnormalities,prolongQTintervalandthepresenceofUwaves,areassociatedwithahigherprevalenceofventriculararrhythmias.

¨ Ventriculararrhythmiaswereseenin21%ofpatientsandwithSCDattributedtoprimaryarrhythmiasin4%.MarfansyndromepatientswithLeftventriculardilationhaveahigherincidenceofprolongQTintervalandventriculararrhythmias.

¨ WomenwithMarfanhavetoworryabouthavingachildwithautosomaldominantdisorderandpregnancyduetotheascendingaorticdilation,whichwilloccurduringpregnancyanddelivery.TheAorticsizetominimizecomplicationsis<4.2cm.Thesepatientsarereferredtocardiologywhowillperformaperiodicechocardiogramduringpregnancy.

¨ Mitralvalveprolapseisanothercondition,whichcanaffectMarfansyndrome.Theincidencecanrangefrom50%and80%ofcases.Marfansyndromepatientswithmitralvalveprolapsepresentwithvariabledegreesofmitralregurgitation,withupto12%to13%havingmoderateorseveremitralregurgitation.¨ Althoughtheassociatedleftventricularvolumeoverloadandsystolicfunctionmaybeassociatedwithsuddencardiacdeath,thisisuncommonbelowtheageof50years.Surgicalrepairoftheseverelyregurgitatedmitralvalveispossibleandhasbeenassociatedwithahighevent-freesurvivalat10years.

¨ ThemeasurementofQTintervalisthedurationofventricularrepolarizationorrestingphaseofventricularmyocardium.ItmeasuresthestartofdepolarizationattheQpointofanekgandtheendofrepolarizationattheendoftheTwaveofanEKGinrelationtotheventricularmyocardium.WhentheQTisprolongthereisariskofventriculararrhythmiaswhichcanresultinearlyafterdepolarizations,provokingTorsadesdesPointes,whichleadstoventricularfibrillation,whichendsinsuddencardiacarrest.(a)

¨ The2015EuropeanSocietyCardiologypanelestablishednewguidelinesondiagnosinglongQTsyndromewithoutasecondcauseofprolongQT.Themeasurementof500milliseconds(ms)wassuggestedasthethresholdforasymptomaticLQTS (withoutafamilyhx ofdisease).ThismeasurementisidenticaltotheQTdurationassociatedwithhighriskforarrhythmiceventsinSCA.ThecorrectedQT(QTc)is>480ms orscoreofthreeforclinicaldiagnosis.IfunexplainedsyncopeispresentthenaQTcwillbe>460ms issufficienttomakediagnosis.(b)

¨ LongQTSyndrome(LQTS)ischaracterizedbyprolongedQTintervalandventriculararrhythmiasmainlytriggeredbyadrenergicactivation.Themeanageatpresentationis14years.TheannualrateofSCDinpatientswithuntreatedLQTS isestimatedtobebetween0.33and0.9%,whereasthatforsyncopeisestimatedtobe5%.Mutationsin13geneshavebeenassociatedwithLQTS,mostencodingforsubunitsofpotassium,sodiumorcalciumvoltagedependentionchannels.Geneticscreeningidentifiesadisease-causingmutationin75%ofLQTS casesandthreemaingenes(KCNQ1,KCNH2andSCN5A)accountfor90%ofpositivelygenotypedcases.TherearesubtypesofLQTS.(b)

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Anelectrocardiogramandgenetictestingisrecommended.Thosepatientswho

surviveaSCA,haveahighriskofrecurrence,evenwhileonBetablockertherapy.

Thereisa14%riskwithin5yearsontherapy.Sincetheriskisthishighan

implantablecardiacdefibrillationishighlyrecommended.Thesepatient’srisk

increasesforSCA ifrecurrenceofsyncopalevents.

PostpartumwomenwithLQTS haveanincreasedriskduringthe9-month

recoveryperiod(especiallywomenwiththeLQT2 genotype).

Silentcarriersofpathogenicmutationspresentamodestriskofcardiacevents

estimatedat10%betweenbirthandage40years;theuseofbeta-blockersshould

beconsideredinthisgroupofpatients.ProphylacticICDtherapymaybe

considered,onanindividualbasis,inhigh-riskpatientssuchaswomenwithLQT2

andQTc.500ms,patientswithQTc.500ms andsignsofelectricalinstabilityand

patientswithhigh-riskgeneticprofiles(carriersoftwomutations,including

Jervell andLange–NielsensyndromeorTimothysyndrome).

¨ (a)AvoidanceofQT-prolongingdrugs

¨ (http://www.crediblemeds.org).

¨ (b)Correctionofelectrolyteabnormalities(hypokalemia,hypomagnesaemia,hypocalcaemia)thatmayoccurduringdiarrhea,vomitingormetabolicconditions.

¨ (c)Avoidanceofgenotype-specifictriggersforarrhythmias(strenuousswimming,especiallyinLQTS1,andexposuretoloudnoisesinLQTS2 patients)

¨ Beta-blockersarerecommendedinpatientswithaclinicaldiagnosisofLQTS.ICDimplantationwiththeuseofbeta-blockersisrecommendedinLQTS patientswithpreviouscardiacarrest.(a)

¨ DruginteractionsplayanimportantroleinthecareofpatientswithpolypharmacyandthepotentialforSCA.Vandenber,Vandael,Robyns,etal.,(2016),didananalysistodeterminewhichQTcorrectionformulatouseinanautomatedQT-monitoringalgorithmintheir

electronicmedicalrecord.TheystudiedratecorrectionperformanceofdifferentQTcorrectionformulaeandtheirimpactonriskassessmentformortality.TheytookfivepublishedQTcorrectionforheartrateanddidacomparisoncalculationwiththefollowingformulas.Bazett9:QTcB=QT/RR1/2;Fridericia10:QTcFri=QT/RR1/3;Framingham11:QTcFra=QT+0.154 (1−RR);Hodges12:QTcH=QT+0.00175 ([60/RR]−60);Rautaharju13:QTcR=QT−0.185(RR−1)+k(k=+0.006secondsformenand+0secondsforwomen)

¨ ThestudyresultedinhavingtwoQTcorrectionforheartrateformulastobeconsistentwhichareFridericia(QTcFri=QT/RR1/3andFramingham(QTcFra=QT+0.154(1-RR),correctionformulashowedthebestratecorrectionandsignificantlyimprovedpredictionof30-dayand1-yearmortality.(a)

¨ ThemostfrequentprolongQTintervalisrelatedtoadversedrugreactions.¨ ThefollowingmedicationshavebeenknowntocauseQTprolongation

haloperidol,vemurafenib,ziprasidone,methadoneandsertindole.Someantiarrhythmicdrugs,suchasamiodaroneorsotalolwillcauseprolongQTintervalsinsomepatients.(2015ESCGuidelines)Otherpotentialdrugssuchassecond-generationantihistamines,suchasastemizole,andhighbloodalcoholconcentrationscanprolongtheQTinterval.ApossibleinteractionbetweenselectiveserotoninreuptakeinhibitorsandthiazidediureticsisassociatedwithQTprolongation.(MacrolideantibioticsarealsosuspectedtoprolongtheQTinterval,afteritwasdiscoveredrecentlythatazithromycinwasassociatedwithanincreaseincardiovasculardeath(USFoodandDrugAdministration,2016)

¨ ShortQTsyndrome(SQTS)

¨ SQTS isdiagnosedinthepresenceofaQTc≤340ms. SQTS shouldbe

consideredinthe

¨ presenceofaQTc≤360ms andoneormoreofthefollowing:

¨ (a)Aconfirmedpathogenicmutation

¨ (b)AfamilyhistoryofSQTS

¨ (c)Afamilyhistoryofsuddendeathat40years

¨ (d)SurvivalfromaVT/VFepisode

¨ ShortQTS istheshortintervaldurationofcardiacrepolarization,which

constitutesthesubstrateforthedevelopmentoflifethreateningarrhythmias.Five

genesarelinkedtoSQTS (KCNH2,KCNQ1,KCNJ2,CACNA1C andCACNB2b),

howevertheyieldofgeneticscreeningremainslow(20%overall).Thedisease

appearstobehighlylethalinallagegroups,includingchildrenintheirfirst

monthsoflife,andtheprobabilityofafirstcardiacarrestbytheageof40yearsis

.40%.Giventhesmallsizeofthepopulationsreportedsofar,thehighlethality

maypartiallyreflectareportingbiasrelatedtoareportingbiasrelatedtothe

underdetectionofSQTS inasymptomaticpatients.

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¨ TherearemultipleothercausesforventriculararrhythmiasincludingBrugada syndrome,catecholaminergic polymorphicventriculartachycardiaandearlydepolarizationsyndrome¨ Congenitalheartdiseaseinchildrenandadults,dependingonthetypeofcardiomyopathywhichwillrequirecardiologyevaluationandlifetimefollowup.

¨ TetralogyofFallot¨ Singleventriculardisease(Hypoplasticleftheart)

¨ VentriculararrhythmiasinastructurallynormalheartarecalledidiopathicVentriculartachycardiaorprematureventricularcontractions.Theseoccurabout70%anditoriginatesfromtherightventricularoutflowtract.OtheroriginsincludetheaorticsinusesofValsalva,LVOT,greatcardiacveins,andepicardialmyocardium,aorta-mitralcontinuityandrarelythepulmonaryartery.

¨ Thisidiopathicarrhythmiamayoccurwithoutstructuralheartdisease;however,subtlewallabnormalitieshavebeendemonstratedonCardiacmagneticresonanceimaginginsomepatients.Theyhaveafocalmechanismsecondarytoautomaticity,micro-re-entryortriggeredactivity.

¨ IdiopathicRVOT–VTtypicallypresentsbetweentheagesof20and50yearsandmorefrequentlyinwomen.Therearetwotypicalforms:exercise/stress-inducedVTandrepetitivemonomorphicVToccurringatrest.RepetitiveNSVToccursin60–92%ofcaseswhileincessantVToccursonlyoccasionally.ParoxysmalsustainedVTseparatedbylongperiodsofinfrequentPVCsislesscommon.Episodesincreaseinfrequencyanddurationduringexerciseand/oremotionalstress;exercisetestsmayprovokefocalOT–VTduringtheexerciseorrecoveryphases.

¨ TypicalQRS morphologyisaninferioraxiswithdominantLBBB morphology.VTismonomorphic,however,theQRS morphologymayvaryslightly.MultipledistinctVTmorphologiesareveryrareandraisethesuspicionforscar-relatedVT,suchasinARVC.AlthoughidiopathicOT–VTfollowsabenigncourse,malignantVTmayoccasionallyoccur.ECGduringsinusrhythmisusuallynormal,however,10%havecompleteorincompleteRBBB.Exercisetestingandcardiacimagingshouldbeperformedtoexcludethepresenceofunderlyingstructuralheartdisease,andcardiaccatheterizationmaybewarrantedinsomecases.

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¨ Treatmentisonlywarrantedifpatientsaresymptomatic.ItisworthnotingthatsymptomsmayberelatedtoLVdysfunction,consideringthatidiopathicVTmaybeacauseoftachycardia-inducedCardiomyopathy.

¨ Insuchpatients,treatmentwithsodiumchannelblockers(classICagents)orcatheterablationshouldbeconsidered.InpatientswithRVOT–VT/PVCs,primarycatheterablationisrecommended,whereasinpatientswithLVOT–VT/PVCs,catheterablationshouldonlybeconsideredafterfailedanti-arrhythmictherapy.ThecloseanatomicalproximityoftheRVOT,LVOT andgreatcardiacveinslimitspreciselocalizationoftheVToriginbasedonQRS morphologyexceptforclassicRVOT tachycardia.

¨ Patientscominginforaphysicalexamifover40yearsolda12leadEKGisrecommended.AnEKGisrecommendedonanyonepresentingwithchestdiscomfort,fainting,ornearsyncope

¨ Anekgshouldbeconsideredonanyonewithacardiacmurmur,familyhx ofsuddencardiacdeath

¨ Patientswhopresentforthefirsttimewithhighbloodpressure>160/90intheofficeshouldhaveanEKGdoneforevaluation.

¨ Patientswithhx ofCAD,HTN,CHF,obeseandover65yearsoldshouldhaveanEKGscreening.AnyabnormalekgshouldbefurtherevaluatedbyCardiologyconsiderationofanechocardiogram.Anyprematurebeatsof2ormoreshouldundergoa24hourholtermonitortoevaluateforPVCorPACburden(normalburdenis1-5%)anythingabove6%orhigheranechocardiogramandatwoweekor30dayeventmonitorisrecommendedforsymptomcorrelation

¨ AnyabnormalechocardiogramwillrequireastresstestorcardiacCTscanwithcontrastvsCardiacMRIwithcontrastespeciallyiflookingforARVD vsCoronaryarterydiseaseorCHFscarring.Cardiologymayrecommendacardiaccatheterizationoftheleftsideforcoronaryangiography,ifCOPDispresentarightsidedcardiaccatheterizationisrecommended,ifechocardiogramPAPis>40mmHG

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