The Frozen Elephant Trunk Technique for Treatment of Thoracic Aortic Aneurysms

24 Pages·2008·1.1 MB·English

Aus der Klinik für Herz-, Thorax-, Transplantations- und Gefäßchirurgie
der Medizinischen Hochschule Hannover

The Frozen Elephant Trunk
Technique for Treatment of Thoracic Aortic Aneurysms

Dissertation zur Erlangung des Doktorgrades der Medizin
in der Medizinischen Hochschule Hannover

vorgelegt von
Hassina Baraki
aus
Kabul

Hannover, November 2007
Angenommen vom Senat der Medizinischen Hochschule Hannover
am 26.02.2008.

Gedruckt mit Genehmigung der Medizinischen Hochschule Hannover

Präsident: Prof. Dr. Dieter Bitter-Suermann

Betreuer: PD Dr. med. Christian Hagl

Referent: PD Dr. med. Gerd Peter Meyer

Korreferent: PD Dr. med. Thomas Becker

Tag der mündlichen Prüfung: 26.02.2008

Promotionsausschussmitglieder:
Prof. Dr. Jürgen Klempnauer
Prof. Dr. Benno Ure
Prof. Dr. Oliver Rühmann
Meiner Mutter gewidmet
Inhaltsverzeichnis I
1. Inhaltsverzeichnis

1. Inhaltsverzeichnis....................................................................................................................I
2. Publikation..............................................................................................................................II
3. Zusammenfassung...................................................................................................................3
3.1. Einleitung..........................................................................................................................3
3.2. Diskussion.........................................................................................................................6
3.3. Zusammenfassung............................................................................................................9
3.4. Literaturverzeichnis........................................................................................................10
4. Lebenslauf..............................................................................................................................14
5. Erklärung nach § 2 Abs. 2 Nr. 5 und 6 Promotionsordnung............................................15
6. Danksagung...........................................................................................................................16
2. Publikation

“The Frozen Elephant Trunk Technique for Treatment of
Thoracic Aortic Aneurysms”

Baraki H, Hagl C, Khaladj N, Kallenbach K, Weidemann J, Haverich A, Karck M.
Ann Thorac Surg. 2007 Feb;83(2):S819-23; discussion S824-31.

Presented at Aortic Surgery Symposium X, New York, NY, April 27–28, 2006.
The Frozen Elephant Trunk Technique for
Treatment of Thoracic Aortic Aneurysms
Hassina Baraki, MD, Christian Hagl, MD, PhD, Narwid Khaladj, MD,
Klaus Kallenbach, MD, PhD, Jürgen Weidemann, MD, Axel Haverich, MD,
and Matthias Karck, MD
DepartmentsofThoracicandCardiovascularSurgeryandRadiology,HannoverMedicalSchool,Hannover,Germany
Background. The frozen elephant trunk technique al- completely in 2. In 1 patient, the descending aorta was
lowsforsingle-stagerepairofcombinedaorticarchand perforated owing to misplacement of the stented end of
descending aortic aneurysms using a hybrid prosthesis the hybrid prosthesis. In 23 of 25 patients with postop-
with a stented and a nonstented end. This report sum- erativecomputedtomographyimaging(>6monthspost-
marizes the operative and follow-up data (mean follow- operatively), complete thrombus formation around the
up:20months)withthisnewtreatment. frozenelephanttrunkwasobserved.
Methods.BetweenSeptember2001andMarch2006,39 Conclusions. This procedure is performed through a
patients (15 women; mean age, 62 years) were operated median sternotomy and combines the concepts of the
onafterapprovalbythelocalInstitutionalReviewBoard. elephant trunk principle and endovascular stenting of
Indications for operation were aneurysms in 18 patients descending aortic aneurysms. Favorable intraoperative
and aortic dissections in 21. The stented end of the and postoperative results in the follow-up with throm-
hybrid prosthesis was placed through the opened aortic busformationaroundthestenteddescendingaorticseg-
archunderfluoroscopiccontrolusinghypothermiccircu- ment has encouraged us to evaluate all patients with
latoryarrestandselectiveantegradecerebralperfusion. thoracicaneurysmsextendingproximalanddistalofthe
Results. All patients survived the procedure. Five pa- leftsubclavianarteryforthistreatment.
tients(12.8%)diedearlypostoperatively,withtwodeaths
directly related to the procedure. Symptoms of neuro- (AnnThoracSurg2007;83:S819–23)
logic dysfunction developed in 5 patients and resolved ©2007byTheSocietyofThoracicSurgeons
Patientswithextensiveaorticaneurysmsinvolvingthe during the time interval between the procedures, or
ascending aorta, aortic arch, and the descending comorbidities preclude another procedure through a
aorta are still considered to be a challenge for many lateral thoracotomy [3, 4].
cardiovascularsurgeons[1].Inthiscontext,majorconcerns To complete the surgical treatment during a single
include the adequate protection of the heart, the man- operation through a median sternotomy, we introduced
agement of the aortic valve, the protection of the brain, the “frozen elephant trunk” procedure [5]. A prototype,
the avoidance of respiratory compromise, and the mini- hybrid prosthesis stent graft (Chavan-Haverich en-
mization of spinal cord injury and organ failure caused dograft,CurativeMedicalDevicesGmbH,Dresden,Ger-
byprolongedcirculatoryarresttimes. many) is placed into the descending aorta in an ante-
In 1983, Borst and colleagues [2] introduced the ele- grade fashion though the opened aortic arch, and the
phanttrunkproceduretofacilitatestagedsurgeryforthe ascendingaortaandtheaorticarcharereplacedconven-
aorticarchandthedistalaorticsegments.Theprocedure tionally [5]. In this article we briefly report our surgical
involves the prosthetic replacement of the ascending experience with this novel combined surgical and inter- NT
aorta and the aortic arch with an elephant trunk exten- E
ventionalapproach. M
sionofthearchgraftintothedescendingaortathrougha E
L
median sternotomy. In a second-stage operation, the P
P
elephant trunk can be extended to the desired level Material and Methods U
S
through a lateral thoracotomy; however, the cumulative Patients
riskforearlymortalityaddsupto15%afterastage-two
Thefrozenelephanttrunkprocedurewasapprovedbythe
repair. Furthermore, many patients fail to return for
Institutional Review Board of Hannover Medical School.
the second operation; they die owing to aortic rupture
BetweenSeptember2001andMarch2006,39patientswith
combinedpathologiesoftheaorticarchandthedescending
PresentedatAorticSurgerySymposiumX,NewYork,NY,April27–28,
2006. aorta were operated on using the hybrid prosthesis. In-
formed consent was required in each case. Mean patient
AddresscorrespondencetoDrBaraki,HannoverMedicalSchool,Depart-
age was 62 years (range, 37 to 78 years), and 11 patients
mentofThoracicandCardiovascularSurgery,Carl-Neuberg-Strasse1,
30625 Hannover,Germany;e-mail:[email protected]. wereolderthan70years;15(38.5%)werewomen.
©2007byTheSocietyofThoracicSurgeons 0003-4975/07/$32.00
PublishedbyElsevierInc doi:10.1016/j.athoracsur.2006.10.083
S820 AORTICSURGERYSYMPOSIUMX BARAKIETAL AnnThoracSurg
FROZENELEPHANTTRUNK 2007;83:S819–23
Table1. AssociatedPreoperativeDisorders releasedbypullingbackboththesheathssimultaneously
whilethepusherisheldsteady.
Disorder No.Patients(%)
In each patient, spiral computed tomography angiog-
Hypertension 31(79.5) raphyofthethoracicaortawasperformedpreoperatively
Chronicpulmonarydisease 8(20.5) toassesstheextentoftheaneurysmordissectionandto
Historyofstroke 2(5.1) determinetheappropriatesizeoftheendograft.
Peripheralvasculardisease 2(5.1)
Surgery
Coronaryarterydisease 11(28.2)
Oldmyocardialinfarction 4(10.3) Cardiopulmonary bypass was used in all patients. Cen-
tral cannulation of the ascending aorta and the right
Chronicatrialfibrillation 2(5.1)
atrium was preferred. In 4 patients (10.3%) who under-
Diabetes 3(7.7)
went resternotomy, the groin vessels were cannulated
Renalinsufficiency 8(20.5)
before because the ascending aortic aneurysm en-
Marfansyndrome 2(5.1)
croached upon the sternum. Core cooling was accom-
Malignancy 2(5.1)
plishedto26(cid:1)2°Crectaltemperature.Afterinductionof
Redocases 12(30.8)
cardioplegiccardiacarrest,cardiopulmonarybypasswas
discontinued.
Theaorticarchwasthenopenedlongitudinally.Selec-
Most patients presented with aortic dissection: 4 tive antegrade cerebral perfusion with cold blood at a
(10.3%)withanacutetypeAaorticdissection,11(28.2%) temperatureof15°Candavolumeof250to450mL/min
with a chronic type A dissection, 3 (7.7%) had an acute wasinitiatedafterostialcannulationoftheleftcommon
typeBaorticdissection,and3(7.7%)hadachronictype carotidarteryandthebrachiocephalictrunk.Afterwards,
B aortic dissection. The indication for intervention in the stented portion of the hybrid prosthesis was de-
patientswithchronicdissectionswasaorticdilatationof ployedinthedescendingaorta.Inthefirst5patients,the
70 (cid:1) 18 mm (range, 50 to 113 mm) in chronic type A implantation was over an antegrade-placed superstiff
dissectionand60(cid:1)5mm(range,55to65mm)inchronic guidewire. Prompted by perforation of the aortic wall
typeBdissection. with the introducer system in a patient with a tortuous
The second most frequent pathology, present in 18 descending aorta, a through-and-through transfemoral
(46.2%), was an aortic aneurysm proximal and distal to guidewiretechniquewasusedinallsubsequentpatients.
theleftsubclavianartery.Themaximalaorticdiameterin Thedistalendingsiteofthestentgraftwasatorabove
these patients was 59 (cid:1) 8 mm (range, 47 to 73 mm). the tenth thoracic vertebra in all patients. After deploy-
Additional cardiac pathology included severe coronary ment, the stented portion of the prosthesis was modu-
artery disease in 11 patients (28.2%) and aortic valve lated onto the aortic wall with the help of an appropri-
disease in 11 (28.2%). Comorbidities are summarized in ately sized balloon catheter (Medtronic, Minneapolis,
Table1. MN).ThenonstentedDacrongraftsegmentwassutured
circumferentially to the aorta distal to the origin of the
Endograft Design left subclavian artery. The supraaortic branches were
The endograft consists of a woven vascular prosthesis then reimplanted en bloc into an appropriately sized
withstainlesssteelstentsaffixedtotheinneraspectsatits window of the graft. A proximal graft-to-aortic anasto-
distalend.Thediametersofthestentswithinthehybrid mosis at any desired level of the ascending aorta com-
prosthesiswere30to46mm,andeachstentwas22mm pletedtherepair.
long. The proximal portion of the hybrid prosthesis was In 23 patients (59%), the entire aortic arch and the
nonstented and consisted of a Dacron sleeve (DuPont, proximalsegmentofthedescendingaortawerereplaced,
Wilmington,DE)forconventionalsurgicalhandling(Fig1). andin11(28.2%),theascendingaortawasalsoreplaced.
The delivery system consists of a flexible 39F outer In 5 (12.8%) other patients whose aneurysms were lim-
S sheath, a 34F inner sheath, and a central pusher. With- ited to the proximal descending aorta, implantation of
U
P drawaloftheoutersheathwhileholdingtheinnersheath the hybrid prosthesis into the descending aorta was
P
LE andthepushersteadyreleasesthestentedportionofthe enabledbyalimited,3-cmto4-cmlongitudinalT-shaped
M
hybrid prosthesis. The proximal Dacron tube is then incision of the aortic arch. The nonstented endograft
E
N
T
Fig1. Thehybridprosthesis(Chavan-Haver-
ichendograft,CurativeGmbH,Dresden,
Germany)madeofawovenvascularprosthe-
siswithstainlessstentsaffixedtotheinner
aspectsatthedistalend.Theproximalend
consistsofaDacronsleeve(DuPont,Wil-
mington,DE)readyforconventionalsurgical
handling.(L(cid:2)length.)
AnnThoracSurg AORTICSURGERYSYMPOSIUMX BARAKIETAL S821
2007;83:S819–23 FROZENELEPHANTTRUNK
Table2. ConcomitantOperativeProcedures
Procedure No.Patients(%)
Coronaryarterybypassgraft 12(30.8)
Aorticvalverepair(Davidprocedure) 7(17.9)
Aorticvalvereplacement(composite) 4(10.3)
segmentwassuturedcircumferentiallydistaltothelevel
of the left subclavian artery before closure of the aorto-
tomy.Twoofthe5patientsrequiredadditionalcomplete
myocardial revascularization. In 21 patients, additional
procedures were required, including aortic valve recon-
structionwithDavidprocedurein7(17.9%),aorticvalve
replacementasacompositein4(10.3%),andmyocardial
revascularizationin12(30.8%)(Table2).
Fig3. Themaximaldiameterofthedescendingthoracicaortaatthe
Results
levelofthetrachealbifurcationbefore(clearbars)andafter(striped
Operative Outcome bars)theimplantationofthehybridprosthesis.(AADA(cid:2)acuteaor-
ticdissectiontypeA;CADA(cid:2)chronicaorticdissectiontypeA;
No intraoperative deaths occurred, but there were five CADB(cid:2)chronicaorticdissectiontypeB.)
cases (12.8%) of early death. The implantation of the
prosthesiswassuccessfulinallbut1patient.Thispatient
hadmarkedkinkingofthedescendingaortadistaltothe that exsanguination resulted from a reopening of the
aneurysmaticsegmenttobeexcluded.Theimplantation repairedsegment.
wastriedoveranantegrade-placedguidewire,butthetip A 72-year-old patient who sustained a medial artery
of the introducer system could not be advanced beyond cerebral infarction died of hemorrhage during elective
the kinked segment. At this point, the aortic wall was tracheotomy on postoperative day 7. A further patient
perforated,whichrequiredsurgicalrepairandadditional died of multiorgan failure after cerebral infarction, and
transfemoral stent graft implantation to bridge the per- another from retroperitoneal hemorrhage after perfora-
foratedandaneurysmaticsegments. tion of the iliac artery. The final patient died of respira-
InonepatientwithchronicaorticdissectiontypeA,the tory failure on postoperative day 31. Among the five
aorticwallofthefalselumendirectlydistaltotheorigin deaths, 2 patients had an aortic aneurysm and 3 had
of the left subclavian artery was accidentally injured chronic type A aortic dissection. Three of the five were
duringsurgicalpreparation.Eventhoughthislaceration redo cases, and 3 patients needed additional coronary
wassuturedandthefurthercourseoftheoperationwas arterybypassgraftsowingtocoronaryarterydisease.
uneventful, the patient died from hemorrhage into the Cardiopulmonary bypass time was 222 (cid:1) 67 minutes,
lefthemithorax2dayspostoperatively.Autopsyrevealed aorticcross-clamptimewas133(cid:1)49minutes,circulatory
arrest time was 69 (cid:1) 19 minutes, and time of selective
antegrade brain perfusion during circulatory arrest was
56 (cid:1) 15 minutes. Vocal cord paralysis occurred in 5
patients(12.8%),3ofwhomwereredocases.Fivepatients
(12.8%) showed central neurologic dysfunction, and in
twothesymptomsresolvedcompletelybeforedischarge.
Two of the 5 patients had a history of stroke, with
correlates in the preoperative CT scan of the brain. T
N
Reexploration for bleeding was necessary in 5 patients
E
M
(12.8%).
E
L
P
Follow-Up P
U
Median follow-up was 22 (cid:1) 17 months, with an overall S
survivalof87%(Fig2).Twopatientswerelosttofollow-
up.PostoperativeCTscanswereobtainedin25(73.5%)of
34 patients, and in 23 (92%), complete thrombus forma-
tion was observed in the perigraft space around the
stented segment of the hybrid prosthesis. The average
diameter of the stented descending thoracic aorta de-
Fig2. Actuarialsurvivalinmonthsafterimplantationofhybrid creasedovertimefrom63(cid:1)14mm(range,47to113mm)
prosthesis.Numbersinparenthesisshowthepatientsremainingat to54(cid:1)11mm(range,39to74mm;Fig3).
riskateachrelevanttimepoint. One patient with chronic aortic dissection exhibited a
S822 AORTICSURGERYSYMPOSIUMX BARAKIETAL AnnThoracSurg
FROZENELEPHANTTRUNK 2007;83:S819–23
small endoleak into the false lumen at the origin of the diastinalapproachwiththehybridprosthesisforpatients
left subclavian artery; otherwise, the false lumen was withascending,arch,anddescendinganeurysms[5].
thrombosed.Thepatientrefusedareintervention,sothe Intheconventionalelephanttrunkoperation,theperi-
exactetiologyoftheendoleakremainsunclear. graftspacearoundtheelephanttrunkremainsperfused,
Intheotherpatientwithchronicaorticdissectiontype therebypromotingfurtheraneurysmaticdilatationofthe
A,thestentedsegmentofthegraftcouldnotbeanchored aortic segment [3, 10]. In contrast, the hybrid prosthesis
successfullyinapreviouslyimplantedthoracoabdominal technique allows for progressive thrombus formation in
aortic stent graft. The stent slipped proximally during theperigraftspaceinthedescendingaortauptothelevel
and after release, giving rise to a distal endoleak. This of the stent. Widening of the descending aorta has not
was treated 2 weeks later by placing a commercially beenobservedinourpatients,regardlessofcompleteor
available endograft (Talent, Medtronic Inc) transfemor- incompletethrombusformation.Thisphenomenonsug-
ally,thusextendingthehybridendograftdistallyintothe gests that the stents within the distal segment of the
thoracoabdominal graft. A type III endoleak, which was hybrid prosthesis are effective in preventing retrograde
reduced to a tiny contrast extravasation, was found at 6 flowintotheaneurysm.
monthfollow-up.Initiallythepatientwastreatedconser- To mount the hybrid prosthesis into an adequately
vatively, but his thoracoabdominal aneurysm was pro- flexible and thin delivery system, we used thin Dacron
gressive,causingconventionalopenrepairafteraninter- (0.36 mm in width), which is thinner than the Dacron
valof3.85years. usedinconventionalaorticsurgery.Thehybridprosthe-
Another patient with chronic aortic dissection type A, sisispretreatedwithcollagenduringfabrication.Insome
who was 55 years old, needed a reoperation after an instances,extrasealingwithfibringluewasnecessaryto
interval of 2.8 years. He underwent an aortic valve renderthegraftcompletelyhemostatic.
replacement and replacement of the ascending aorta The initial learning curve and the high incidence of
withacompositegraft.Elevenyearslater,hisaorticarch concomitant procedures (Table 2) may explain the peri-
and his descending aorta were replaced with a hybrid operative mortality rate of 12.8% [7, 11, 12]. However,
prosthesis. Follow-up CT imaging showed an anasto- groups describing one-stage surgical replacement of
motic aneurysm up to 58 mm, causing a re-replacement the thoracic aorta have also reported mortality rates of
of the ascending aorta and proximal aortic arch. The between 14% and 16% [11, 13]. A major technical im-
patientdidwellandwasdischargedhomeonpostoper- provementovertimewastheintroductionofaguidewire
ativeday9. throughthefemoralarterythathelpstodiscriminatethe
trueandthefalselumen.
The 12.8% incidence of stroke remains a concern be-
Comment
causeitishigherthanexpected[12].In2ofthe5patients,
The development of the elephant trunk procedure for however, symptoms resolved completely before dis-
aneurysm of the ascending, arch, and descending tho- charge, and 2 were at higher risk owing to previous
racic aorta has improved the repair of complex aortic cerebrovascular incidents. Three of the 5 patients who
lesions by facilitating the proximal anastomosis at the developedrecurrentnerveparalysiswereredocases.
timeofthesecond-stagedescendinganeurysmrepair[2, Thepositionofthedistalanastomosisisquitecloseto
6, 7]. Sometimes complications with the first operation the recurrent nerve. Special attention should be paid to
render the completion of the second operation unfeasi- the preparation of the aortic arch to save the nerve.
ble. The second intervention carries the cumulative risk Recurrentnerveparalysisnotonlyreducesthepatient’s
oftwomajorprocedures,anadditionalriskformortality quality of life but also survival by leading to disorders
upto5%[8],andaspinalcordinjuryriskof3%to10%[9]. including aspiration pneumonia. Rehabilitation should
Accordingly,wehavedevelopedasingle-stagetransme- thereforebeperformedconsistentlyandatanearlystage.
S Fig4. Contrastcomputedtomographyrefor-
U
P mationofapatientwithaorticaneurysmafter
P
L implantationofahybridprosthesis26months
E
M postoperatively.Perigraftspacearoundthe
EN stentedsegmentofthehybridprosthesisis
T completelythrombosed.
AnnThoracSurg AORTICSURGERYSYMPOSIUMX BARAKIETAL S823
2007;83:S819–23 FROZENELEPHANTTRUNK
Noparaplegiacausedbyspinalcordinjurydeveloped 2. Borst HG, Walterbusch G, Schaps D. Extensive aortic re-
inpatientsinourseries.Thisrateisquitelowcompared placement using “elephant trunk” prosthesis. Thorac Car-
diovascSurg1983;31:37–40.
withthesignificantparaplegiaratesreportedwithsimilar
3. EstreraAL,MillerCC,PoratEE,HuynhTT,WinnerkvistA,
opensurgicalapproaches,butitcorrelateswithendovas-
Safi HJ. Staged repair of extensive aortic aneurysms. Ann
cularstentgraftreportsofthedescendingaorta[14–16]. ThoracSurg2002;74:S1803–5;discussionS1825–32.
The main reason for the reduced spinal cord injury 4. Schepens MA, Dossche KM, Morshuis WJ. The elephant
frequency in our series might be in the indication for trunk technique: operative results in 100 consecutive pa-
tients.EurJCardiothoracSurg2002;21:276–81.
hybridprosthesis,whichwaslimitedtopatientswithan
5. Karck M, Chavan A, Hagl C, Friedrich H, Galanski M,
aneurysmthatinvolvedonlythefirsthalfofthedescend- Haverich A. The frozen elephant trunk technique: a new
ing aorta, regardless of its size. Furthermore, stent graft treatmentforthoracicaorticaneurysms.JThoracCardiovasc
fabrication was adjusted specifically to each patient’s Surg2003;125:1550–3.
6. BorstHG,FrankG,SchapsD.Treatmentofextensiveaortic
individual pathology. The proximal extent of the aneu-
aneurysms by a new multiple-stage approach. J Thorac
rysm with regard to arch involvement was not critical
CardiovascSurg1988;95:11–3.
becausethequalityoftheanastomosisdistaltotheorigin 7. HeinemannMK,BuehnerB,JurmannMJ,etal.Useofthe
of the subclavian artery is rather dependent on the “elephant trunk technique” in aortic surgery. Ann Thorac
condition of the aortic tissue than on the actual aortic Surg1995;60:2–6;discussion7.
8. Svensson LG, Crawford ES, Hess KR. Deep hypothermia
diameteratthatsegment.
with circulatory arrest. Determinants of stroke and early
The use of the hybrid prosthesis enables safe anchor- mortalityin656patients.JThoracCardiovascSurg1993;106:
ing of its proximal vascular graft segment by a circum- 19–28;discussion28–31.
ferential, hand-sewn anastomosis distal to the origin of 9. WilliamsGM,PerlerBA,BurdickJF.Angiographiclocaliza-
the left subclavian artery. This is at the expense of a tion of spinal cord blood supply and its relationship to
postoperativeparaplegia.JVascSurg1991;13:23–33;discus-
probably somewhat extended circulatory arrest time
sion33–5.
compared with the time required for antegrade implan- 10. Kouchoukos NT, Masetti P, Rokkas CK. Single-stage reop-
tation of a conventional stent graft with or without its erativerepairofchronictypeAaorticdissectionbymeansof
fixationbyinternalstaysutures. thearch-firsttechnique.JThoracCardiovascSurg2001;122:
578–82.
Similar to observations during follow-up after endo-
11. Bachet J, Guilmet D, Goudot B. Antegrade cerebral perfu-
vascular stent grafting, we observed either advanced or
sionwithcoldblood:a13-yearexperience.AnnThoracSurg
completed thrombus formation around the frozen ele- 1999;67:1874–8;discussion1891–4.
phanttrunkafterameanfollow-uptimeof22monthsso 12. SvenssonLG,KimKH,BlackstoneEH,etal.Elephanttrunk
far (Fig 4) [17]. In some cases, we found additional procedure: newer indications and uses. Ann Thorac Surg
2004;78:109–16;discussion109–16.
shrinkageofthethrombosedaneurysms,whichisalsoa
13. MinaleC,SplittgerberFH,ReifschneiderHJ.Replacementof
common finding after endovascular stent grafting [18]. theentirethoracicaortainasinglestage.AnnThoracSurg
Thrombusformationintheperigraftspaceandshrinkage 1994;57:850–5.
oftheexcludedaneurysmareindicativeofareductionof 14. WonJY,LeeDY,ShimWH.Electiveendovasculartreatment
ofdescendingthoracicaorticaneurysmsandchronicdissec-
aorticwallstress,therebyreducingtheriskofruptureof
tionswithstent-grafts.JVascIntervRadiol2001;12:575–82.
the stented aortic segment. This finding supports the
15. Usui A, Fujimoto K, Ishiguchi T, Yoshikawa M, Akita T,
therapeutic concept of a single-stage antegrade com- UedaY.Cerebrospinaldysfunctionafterendovascularstent-
binedopenandendovascularrepairofcomplexthoracic graftingviaamediansternotomy:thefrozenelephanttrunk
aortic aneurysm using a hybrid prosthesis, despite the procedure. Ann Thorac Surg 2002;74:1821–4; discussion
1825–32.
currently relatively high mortality and morbidity rates.
16. Mizuno T, Toyama M, Tabuchi N, Wu H, Sunamori M.
We believe the morbidity and mortality rates of this Stentedelephanttrunkprocedurecombinedwithascending
procedurewilldecreasewithincreasedexperience,mak- aorta and arch replacement for acute type A aortic dissec-
ingitthetreatmentofchoiceforcomplexaorticdiseases. tion.EurJCardiothoracSurg2002;22:504–9.
17. ChavanA,LotzJ,OelertF,GalanskiM,HaverichA,KarckM.
Endoluminaltreatmentofaorticdissection.EurRadiol2003;
References 13:2521–34.
18. Yamazaki I, Imoto K, Suzuki S, et al. Midterm results of T
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1. Svensson LG. The elephant trunk procedure: uses in com- stent-graft repair for thoracic aortic aneurysms: computed
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plexaorticdiseases.CurrOpinCardiol2005;20:491–5. tomographicevaluation.ArtifOrgans2001;25:223–7. M
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