Variants of Ventricular Preexcitation: Recognition and Treatment

166 Pages·2006·3.62 MB·English

by  Eduardo Back Sternick

Variants of
Ventricular
Preexcitation
RECOGNITION AND
TREATMENT
Eduardo Back Sternick,
MD, PhD
BiocorInstituto
ArrhythmiaandElectrophysiologyUnit
BeloHorizonte
MinasGerais,Brazil
Hein JJ Wellens,
MD, PhD, FACC, FESC,
FAHA, FRCP
UniversityofMaastricht
ProfessorofCardiology
Maastricht,Netherlands
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Variants of
Ventricular Preexcitation
RECOGNITION AND TREATMENT
This Page Intentionally Left Blank
Variants of
Ventricular
Preexcitation
RECOGNITION AND
TREATMENT
Eduardo Back Sternick,
MD, PhD
BiocorInstituto
ArrhythmiaandElectrophysiologyUnit
BeloHorizonte
MinasGerais,Brazil
Hein JJ Wellens,
MD, PhD, FACC, FESC,
FAHA, FRCP
UniversityofMaastricht
ProfessorofCardiology
Maastricht,Netherlands
(cid:1)C 2006EduardoBackSternickandHeinJ.Wellens
PublishedbyBlackwellPublishing
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Firstpublished2006
1 2006
ISBN-13:978-1-4051-48436
ISBN-10:1-4051-48438
LibraryofCongressCataloging-in-PublicationData
Sternick,EduardoBack.
Variantsofventricularpreexcitation:recognitionandtreatment/EduardoBackSternick,
HeinJ.Wellens.
p. ; cm.
Includesbibliographicalreferencesandindex.
ISBN-13:978-1-4051-4843-6(alk.paper)
ISBN-10:1-4051-4843-8(alk.paper)
1.Wolff-Parkinson-Whitesyndrome. 2.Excitation(Physiology)
[DNLM:1.Pre-Excitation,Mahaim-Type. 2.Myocardium–pathology.WG330S839v2006]
I.Wellens,H.J.J. II.Title.
RC685.W6S74 2006
616.1(cid:2)24–dc22
2006007279
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Contents
Foreword,vii
Acknowledgements,ix
1 Historicalnotesandclassificationofthevariants
ofventricularpreexcitation,1
2 Theanatomyofdecrementallyconductingfibers,7
3 Atriofascicularpathwaysanddecrementallyconductinglong
atrioventricularpathways,15
4 TheshortAVdecrementallyconductingfibers,59
5 NodoventricularandNodofascicularfibers,75
6 Fasciculoventricularfibers,83
7 Conductiondisturbancesinaccessorypathways,103
8 Automaticityindecrementallyconductingfibers,117
9 Differentialdiagnosisofleftbundlebranchblock-shaped
tachycardias,131
Index,149
Acolourplatesectionfacesp.22
v
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Foreword
Preexcitationsyndromeshavefascinatedphysiciansfordecades.Mostofthe
interestisfocusedontheWolff–Parkinson–Whitesyndrome,whichhasbeen
anatomicallyandpathophysiologicallycharacterizedingreatdetail.Thisbook,
titledVariantsofVentricularPreexcitation:RecognitionandTreatment,byEduardo
SternickandHeinWellensoffersinsightintothemanyvariantformsofpreex-
citationthatarenotwellrecognized.
Afterreviewingthehistoryofthesevariantsanddiscussingtheirpatholog-
icalaspects,theseauthorshaveputtogetheracompendiumofwell-described
electrocardiographically and extremely well characterized electrophysiolog-
ically variant accessory pathways with which electrophysiologists still lack
experience.Theinitialchapterreviewingthehistoryandanatomyofthepath-
waysisveryusefulinplacinginperspectivethedifferencesbetweenthepatho-
logicandclinicalaspectsofthesevariantforms.Adifferentclassificationofpre-
excitation syndromes is proposed, with the most important characteristic of
themajorityofthesevariantsbeingdecrementalconduction.WhiletheWolff–
Parkinson–Whitesyndromeinvolvesshortatrioventricularbypasstractswith
rapid conduction, the variants that have been described in this volume in-
cludeshortandlongdecrementallyconductingatrioventricularbypasstracts
anddecrementallyconductingatriofascicularbypasstracts.Theoutlyerinthe
grouparethefasciculoventricularbypasstracts,whichhavenodecremental
propertiesandnoparticipationinactivereentrantarrhythmiasbutleadtocuri-
ouselectrocardiographicabnormalitiesthatmustberecognizedbyclinicians.
Extensivediscussionsoftheelectrophysiologicalcharacteristicsofallofthese
formsofpreexcitationarewellpresented.Awealthofinformationexistsinthis
textthatcanbefoundnowhereelse.Examplesofthesevariantsandtheirelec-
trophysiologicalfeaturesareclearlydepictedandprovideinsightsthatcannot
be found in any single source. The treatment of the decrementally conduct-
ingbypasstractsisdescribedandis,asexpected,primarilyablative.Howto
define the presence of these bypass tracts and distinguish them from others
isandremainsaverydifficultbutnecessarytestifoneistohaveasuccessful
ablativetherapy.Theexplanationsofhowtoevaluateeachoftheseformsof
preexcitation in the laboratory and make the diagnosis correctly is a major
featureofthetext.Insomeways,VariantsofVentricularPreexcitation:Recogni-
tionandTreatmentprovidesauniqueopportunityforgeneralcardiologistsand
vii
viii Foreword
electrophysiologiststofindinonetexttheintricaciesofrecognizingandtreat-
ingagroupofdisordersthathasintriguedphysiciansformorethan100years.
MarkE.Josephson,MD
Chief,CardiovascularDivision
BethIsraelDeaconessMedicalCenter
Boston,USA