- Email: [email protected]
Transthoracic Cardioversion of Atrial Fibrillation and Flutter: Standard Techniques and New Advances
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Directcurrentelectric shockshavebeenusedto tvmni- beusedwithhand-heldpaddlesto reducetransthomcic nateatrialarrhythmias (cardioversion) in humanssince impedanceand maximizecurrentflow.. Electrodes toavoidshunting of current the 1960s.The likelihoodof successful cardioversion shouldbewidelysepamted Generally, and maintenance of sinusrhythmis increased if theleft along the chestwall belweenelectrodes. atriumis notmarkedlyenlargedand fibrotic,if thereis electrodes shouldbe large in size; small“pediatric” nomarkedleftatrialhypmtension (e.g.,mi~l stmosis), electrodes shouldonlybeusedininfants<1 yearof age shouldalwaysbesynchronized tothe and if thearrhythmiais notlong-standing. Tominimize (c1O kg).Shacks the risk of ihrombaembolic phenoniena,therap@ic Rwaveto avoidihevulnembleperiodandtheinadverinduction of ventricular fib”llation.Initialshocks for anticoagulation shouldbe established for at least3 tent” shouldbeginat 100J;atrialfluitergenweeksbeforeandfor 4 weeksaftercardioversion; cw- a~”alfibrillation madinis usuallyusedfor thispurpose.A marerecent erallyrequiresa smallershock(initialshocksat 50 J). anesthesia, notmerelysedation,is requiredto approachusesiransesophageal echacardiagraphy to Effective demonstrate theabsenceof thrambiin the leftatrium achieveamnesiaand avoid pain. Excitingnewdevelhave ocand leftatrialappendage.If nothrombiareevident,48 opmentsin defibrillationand cardioversion thatexcessive energyand hoursof heparinanticaagulaiion maybeadequate prior curred.Itis nowunderstood to cardioversion. Anticoagulation is stillrequiredafter currentmayinducecardiacdamage,and recentstudies suchdamagemaybe mediatedin partby free sian.Quinidineanddigitalis,singlyor in com- suggest Cardkwer bination,are frequentlyusedto achieveand maintain radicals.New shackwaveforms,suchas biphasicand wavefwmsfrom multipleencirclingelecsinusrhythmin association withcardioversion. Forthe muhiphasic trodes,may be superiorto thestandarddampedsinuPracedureitself, traditional hand-held-@Me&ctr odes so-kial waveform. or self-adhesive electrode padsmaybeused;theapex(AmJCardiol1996;78(suppl 8A):22-26) anteriorandanterior+sterior positions areequallyeffe@ve. &l coupkmts and firm pressure shouldahvays
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a STANDARD CARDIOVERSION TECHNIQUES Patient selection:
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Thromboembcdism andanticaagulation:
a From the Departmentof InternalMedicine, University of Iowa Haspitals and Clinics, Iowa City, Iowa. Address for reprints: Richard E. Kerber, MD, Departmentof internal Medicine, University of Iowa Hospital, 200 Hawkins Drive, lowa City, lowa 52242.
22
01996 by ExcerptaMedica, Inc. All rightsreserved.
0002-9149/96/$15.00 PllS0002-9149(96)00562-0
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a a a Antiarrhythmic drug therapy:
synchronization:
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Ekctradetype and placemenfi
A SYMPOSIUM:
TREATMENT
OF ATRIA1 FIBRILLATION AND FIUITER
23
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Transthoracic current,impedance, and energy:
I Good Electrode Technique ● ● ● ●
24
Wide electrodeseparation; no gel be~een electrodes Firm paddltihest contactpressure Use a couplant Avoid on-breast electrodeplacementin women
THE AMERICAN JOURNAL OF Cardiology@
VOL 78 (8A)
OCTOBER
17, 1996
L
Induction ofvenkicular fibrillation bysm rio& prow yx%xamMosbY.=)
camplicatian.
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swflmnimtion,
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woveforms: a
a
NEW DEVELOPMENTS IN ELECTRICAL CARDIOVERSION in@y: Defibrilkstion
Determinants af Transthoracic impedance ● ● ● ● ● ● ● ●
a A SYMPOSIUM:
tnterelectrode distance (chest size) Electrode size Paddl~hest cantoct pressure Use OFan electrod=hest wall couplant Previous direct< urrent shocks Previous sternotomy Phase of respiration Selected energy
TREATMENT
OF ATRIAL FIBRILLATION AND FLUTER
25
%
i r
r
J
by exfemallysppliedelebtriccormfershock,
BlswkPU,FarkinD, SagarKB,KbmdedaBJ,LeuongDY.GallowayJM,Fenely MP, “ a
Peak
9. LsupaeisA, AlberaG, Dslen J, Dunn M, FeinbergW, JscobsonA. Anti-
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a h MG,
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MK, Spencer KT, Smids Rs, Shamla
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Duration(UMcc) A
2 J
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THE AMERICAN JOURNAL OF CARDIO1OGY”
VOL 78 (8A]
OCTOBER
17, 1996
F
$ A MD
Directcurrentelectric shockshavebeenusedto tvmni- beusedwithhand-heldpaddlesto reducetransthomcic nateatrialarrhythmias (cardioversion) in humanssince impedanceand maximizecurrentflow.. Electrodes toavoidshunting of current the 1960s.The likelihoodof successful cardioversion shouldbewidelysepamted Generally, and maintenance of sinusrhythmis increased if theleft along the chestwall belweenelectrodes. atriumis notmarkedlyenlargedand fibrotic,if thereis electrodes shouldbe large in size; small“pediatric” nomarkedleftatrialhypmtension (e.g.,mi~l stmosis), electrodes shouldonlybeusedininfants<1 yearof age shouldalwaysbesynchronized tothe and if thearrhythmiais notlong-standing. Tominimize (c1O kg).Shacks the risk of ihrombaembolic phenoniena,therap@ic Rwaveto avoidihevulnembleperiodandtheinadverinduction of ventricular fib”llation.Initialshocks for anticoagulation shouldbe established for at least3 tent” shouldbeginat 100J;atrialfluitergenweeksbeforeandfor 4 weeksaftercardioversion; cw- a~”alfibrillation madinis usuallyusedfor thispurpose.A marerecent erallyrequiresa smallershock(initialshocksat 50 J). anesthesia, notmerelysedation,is requiredto approachusesiransesophageal echacardiagraphy to Effective demonstrate theabsenceof thrambiin the leftatrium achieveamnesiaand avoid pain. Excitingnewdevelhave ocand leftatrialappendage.If nothrombiareevident,48 opmentsin defibrillationand cardioversion thatexcessive energyand hoursof heparinanticaagulaiion maybeadequate prior curred.Itis nowunderstood to cardioversion. Anticoagulation is stillrequiredafter currentmayinducecardiacdamage,and recentstudies suchdamagemaybe mediatedin partby free sian.Quinidineanddigitalis,singlyor in com- suggest Cardkwer bination,are frequentlyusedto achieveand maintain radicals.New shackwaveforms,suchas biphasicand wavefwmsfrom multipleencirclingelecsinusrhythmin association withcardioversion. Forthe muhiphasic trodes,may be superiorto thestandarddampedsinuPracedureitself, traditional hand-held-@Me&ctr odes so-kial waveform. or self-adhesive electrode padsmaybeused;theapex(AmJCardiol1996;78(suppl 8A):22-26) anteriorandanterior+sterior positions areequallyeffe@ve. &l coupkmts and firm pressure shouldahvays
E
a a P
a
a STANDARD CARDIOVERSION TECHNIQUES Patient selection:
a a
Thromboembcdism andanticaagulation:
a From the Departmentof InternalMedicine, University of Iowa Haspitals and Clinics, Iowa City, Iowa. Address for reprints: Richard E. Kerber, MD, Departmentof internal Medicine, University of Iowa Hospital, 200 Hawkins Drive, lowa City, lowa 52242.
22
01996 by ExcerptaMedica, Inc. All rightsreserved.
0002-9149/96/$15.00 PllS0002-9149(96)00562-0
@ 3 4 a
A
a a
2 (
a
a a a Antiarrhythmic drug therapy:
synchronization:
R a
Ekctradetype and placemenfi
A SYMPOSIUM:
TREATMENT
OF ATRIA1 FIBRILLATION AND FIUITER
23
A
h 1
e
a
a
Transthoracic current,impedance, and energy:
I Good Electrode Technique ● ● ● ●
24
Wide electrodeseparation; no gel be~een electrodes Firm paddltihest contactpressure Use a couplant Avoid on-breast electrodeplacementin women
THE AMERICAN JOURNAL OF Cardiology@
VOL 78 (8A)
OCTOBER
17, 1996
L
Induction ofvenkicular fibrillation bysm rio& prow yx%xamMosbY.=)
camplicatian.
R
swflmnimtion,
a
woveforms: a
a
NEW DEVELOPMENTS IN ELECTRICAL CARDIOVERSION in@y: Defibrilkstion
Determinants af Transthoracic impedance ● ● ● ● ● ● ● ●
a A SYMPOSIUM:
tnterelectrode distance (chest size) Electrode size Paddl~hest cantoct pressure Use OFan electrod=hest wall couplant Previous direct< urrent shocks Previous sternotomy Phase of respiration Selected energy
TREATMENT
OF ATRIAL FIBRILLATION AND FLUTER
25
%
i r
r
J
by exfemallysppliedelebtriccormfershock,
BlswkPU,FarkinD, SagarKB,KbmdedaBJ,LeuongDY.GallowayJM,Fenely MP, “ a
Peak
9. LsupaeisA, AlberaG, Dslen J, Dunn M, FeinbergW, JscobsonA. Anti-
t
i
.
r
El
E~”-’
ICI
A 4
a h MG,
A J
MK, Spencer KT, Smids Rs, Shamla
A
Duration(UMcc) A
2 J
a
THE AMERICAN JOURNAL OF CARDIO1OGY”
VOL 78 (8A]
OCTOBER
17, 1996