Rev. Bras. Anestesiol. vol.68 número1

Consensus

on

Perioperative

Transesophageal

Echocardiography

of

the

Brazilian

Society

of

Anesthesiology

and

the

Department

of

Cardiovascular

Image

of

the

Brazilian

Society

of

Cardiology

Marcello

Fonseca

Salgado-Filho

,

Samira

Saady

Morhy

,

Henrique

Doria

de

Vasconcelos

,

Eric

Benedet

Lineburger

,

Fabio

de

Vasconcelos

Papa

,

Eduardo

Souza

Leal

Botelho

,

Marcelo

Ramalho

Fernandes

,

Maurício

Daher

,

David

Le

Bihan

,

Chiara

Scaglioni

Tessmer

Gatto

,

Cláudio

Henrique

Fischer

,

Alexander

Alves

da

Silva

,

Carlos

Galhardo

Júnior

,

Carolina

Baeta

Neves

,

Alexandre

Fernandes

,

Marcelo

Luiz

Campos

Vieira

a_{NúcleoVida---EcocardiografiaTransesofágicaIntraoperatóriadaSociedadeBrasileiradeAnestesiologia(ETTI/SBA),Riode}

Janeiro,RJ,Brazil

b_{UniversidadeFederaldeJuizdeFora(UFJF),JuizdeFora,MG,Brazil}

c_{DepartamentodeImagemCardiovasculardaSociedadeBrasileiradeCardiologia(DIC/SBC),SãoPaulo,SP,Brazil} d_{HospitalIsraelitaAlbertEinstein,SãoPaulo,SP,Brazil}

e_{UniversidadeFederaldoValedaSãoFrancisco(Univasf),Petrolina,PE,Brazil} f_{JonhsHopkinsUniversity,Baltimore,USA}

g_{HospitalSãoJosé,Criciúma,SC,Brazil} h_{TakaokaAnestesia,SãoPaulo,SP,Brazil}

i_{InstitutoNacionaldeCardiologia(INC),RiodeJaneiro,RJ,Brazil}

j_{UniversidadedoEstadodoRiodeJaneiro(UERJ),RiodeJaneiro,RJ,Brazil} k_{HospitalPró-Cardíaco,RiodeJaneiro,RJ,Brazil}

l_{HospitalCopaStar,RiodeJaneiro,RJ,Brazil}

m_{InstitutodeCardiologiadoDistritoFederal,Brasília,DF,Brazil} n_{InstitutoDantePazzanesedeCardiologia,SãoPaulo,SP,Brazil} o_{HospitaldoRimeHipertensão,SãoPaulo,SP,Brazil}

p_{GrupoDasa,SãoPaulo,SP,Brazil}

q_{InstitutodoCorac¸ão(Incor),SãoPaulo,SP,Brazil}

∗_{Correspondingauthor.}

E-mail:mfonsecasalgado@hotmail.com(M.F.Salgado-Filho). https://doi.org/10.1016/j.bjane.2017.09.001

r_{FaculdadedeMedicinadaUniversidadedeSãoPaulo(FMUSP),SãoPaulo,SP,Brazil} s_{UniversidadeFederaldeSãoPaulo(Unifesp),SãoPaulo,SP,Brazil}

t_{SãoPauloServic¸osMédicosdeAnestesia(SMA),SãoPaulo,SP,Brazil}

Received20June2017;accepted17July2017 Availableonline16October2017

KEYWORDS

Echocardiography; Transesophageal; Perioperative

Abstract Through the Life Cycle of Intraoperative Transesophageal Echocardiography

(ETTI/SBA)theBrazilianSocietyofAnesthesiology,togetherwiththeDepartmentof

Cardiovas-cularImageoftheBrazilianSocietyofCardiology(DIC/SBC),createdataskforcetostandardize

theuseofintraoperativetransesophagealechocardiographybyBraziliananesthesiologistsand

echocardiographersbasedonscientificevidencefromtheSocietyofCardiovascular

Anesthesiol-ogists/AmericanSocietyofEchocardiography(SCA/ASE)andtheBrazilianSocietyofCardiology.

©2017SociedadeBrasileiradeAnestesiologia.PublishedbyElsevierEditoraLtda.Thisisan

openaccessarticleundertheCCBY-NC-NDlicense(

http://creativecommons.org/licenses/by-nc-nd/4.0/).

PALAVRAS-CHAVE

Ecocardiografia; Transesofágico; Perioperatório

ConsensosobreEcocardiografiaTransesofágicaPerioperatóriadaSociedadeBrasileira deAnestesiologiaedoDepartamentodeImagemCardiovasculardaSociedade BrasileiradeCardiologia

Resumo A Sociedade Brasileira de Anestesiologia, pelo Núcleo Vida de Ecocardiografia

TransesofágicaIntraoperatória(ETTI/SBA)juntamentecomoDepartamentodeImagem

Cardio-vasculardaSociedadeBrasileiradeCardiologia(DIC/SBC),fezumaforc¸a-tarefaparanormatizar

afeituradaecocardiografiatransesofágicaintraoperatóriaparaosanestesiologistase

ecocar-diografistasbrasileiroscombasenasevidênciascientíficasdaSociedadedosAnestesiologistas

Cardiovasculares/SociedadeAmericanadeEcocardiografia(SCA/ASE)edaSociedadeBrasileira

deCardiologia.

©2017SociedadeBrasileiradeAnestesiologia.PublicadoporElsevierEditoraLtda.Este ´eum

artigoOpen Accesssobumalicenc¸aCCBY-NC-ND(

http://creativecommons.org/licenses/by-nc-nd/4.0/).

Introduction

Sinceitsintroductioninclinicalpracticeinthelate1980s, transesophagealechocardiogram (TEE)hasbecome oneof the main diagnostic modalities in cardiology, as it guides anesthetic/surgicalproceduresand reducesmorbidityand mortalityincardiacsurgeries.1_{Duetothegreatproximity} oftheesophagustotheheart,totheabsenceofbonesor lungtissue,andtheuseofhighfrequencytransducers,itis possibletoobtainhighqualityimages.1

The first guideline onperioperative TEE was published in 1999 by the Society of Cardiovascular Anesthesiol-ogists/American Society of Echocardiography (SCA/ASE), whichdefinedthenomenclatureandthe20 cross-sections forbasic TEE.2_{In Brazil,we have theBrazilian Society of} Cardiology (SBC) guidelines on the use of TEE.3 _The lev-elsofevidenceandindicationsforusingTEEincardiacand non-cardiacsurgeriesareshowninTable1.

The SCA/ASE and SBC guidelines define professionals qualified touse echocardiographyas a diagnosticmethod or as hemodynamic monitoring according to their basic andadvancedknowledge criteria.1,3_{In Brazil,the areaof}

perioperativeechocardiographyactivityisbeingdefinedby the Brazilian Society of Anesthesiology (SBA) andSBC. As afirststepinthe standardizationof thisqualificationand in ordertopromotecontinuingeducationtoitsmembers, in the last five years the SBA has taught the course of intraoperativeechocardiography(ETI/SBA),dividedintotwo modules,basic(ModuleI)andadvanced(ModuleII).4

Thus,theSBAandDIC/SBCconsensusonintraoperative TEEaimstostandardizeintraoperativeechocardiographyfor Braziliananesthesiologistsandechocardiographersbasedon thescientificevidenceofASE/SCAandSBC.

Equipment

Congenitalheartdiseasesurgerywith

cardiopulmonarybypass

I

Placementofintracardiacdevices I

Assessmentoflocalizedorposteriorpericardial

effusion

I

Assessmentoftranscatheterprocedures

(interatrialcommunicationclosure,atrial

appendageocclusion,transcathetervalve

procedures)

I

Myocardialfunctionassessmentaftermyocardial

revascularizationwithorwithout

cardiopulmonarybypass

IIa

Largenon-cardiacsurgeryinhigh-riskpatients IIa

theTEEtransducermaybeattachedtoaspecificpartofthe esophagusorstomach,whichallowsamoredetailed anal-ysisofthecardiacanatomy.1,5_{ThecurrentTEEtransducers} operateatafrequencyof3.5---7MHz,reachingupto20MHz.5 Most adult TEE probes have twoknobs onthe handle. Oneforanteflexandretroflexmovementsandtheotherfor lateralmovement,clockwiseandcounterclockwise.1 Multi-planetransducershaveultrasonicbeamanglecontrol,which

TEE-related complications may be separated into two groups: (1) Direct esophageal, stomach and/or airway trauma;(2)TEEindirecteffects(Table2).1

In group 1, complications include esophageal bleed-ing,burning,dysphagia,andlaryngealdiscomfort.6_Mostof thesecomplicationsoccur duringthecatheterpassage.In patientsundergoingcardiopulmonarybypass,theprobe pas-sageshould occur prior to heparinization and withdrawal shouldoccur only after reversal withprotamine and with activatedclottingtime(ACT)lessthan120s.1

Inastudy of10,000 TEEexams,therewasonecase of hypopharyngealperforation (0.01%),twocasesof cervical esophagealperforation(0.02%),andnocaseofgastric per-foration.Theincidenceof morbidityandmortalityis0.2% andzero,respectively.8

The most common complications associated with the intraoperative use of TEE are: odynophagia (0.1%), den-talinjury(0.03%),orotrachealtubemisplacement(0.03%), upper gastrointestinal bleeding (0.03%), and bacteremia (0---17%). Although the incidence of bacteremia is high, thereisnocorrelationwiththedevelopmentofinfectious endocarditis.8

Proximity of transducer with left atrium and

pulmonary veins Transesophageal

probe Upper-esophageal cross-_{section (20–25 cm)}

Mid-esophageal cross-section (30–40 cm)

Transgastric cross-section (40–45 cm)

Deep transgastric cross-section (45–50 cm)

0.º 180.º 90.º Forward rotation Backward rotation Advance Turn to the

right Withdrawal

Turn to the

left Right Left Anterior

Anteflex Retroflex Posterior

Flex to the right

Flex to the left

Figure2 Probeandtransducerhandlingmovementstoacquireechocardiographicimages.AdaptedfromGalhardoetal.6

Table2 Transesophagealechocardiographycomplications.

Airwayandesophagusdirecttrauma

Esophagealbleeding

Esophagealburn

Dysphagia Bacteremia

Vocalcordparalysis

Indirecteffects

Hemodynamicandpulmonarychanges

Inadvertentairwaymanagement

Distractionduringpatientcare

Ingroup2,we havecomplicationsindirectlyrelatedto TEE,whichinclude:hemodynamic,pulmonarychanges, air-waymanipulations,anddistractionduringpatientcare.8_It isimportanttoleaveallanesthesiaworkstationand moni-toralarmsturnedon,astheTEEdevicemaybepositioned ina waythatmakesit difficult tosee allthe monitorsat once.Furthermore,duringexamination,theexaminermay becomeinattentivewiththepatientandattempttodosome echocardiographic imaging or make a diagnosis. Initially, echocardiographicexamination withasecond anesthesiol-ogistatsiteisimportantsothat,whileoneanesthesiologist performs the echocardiographic exam, the other helpsin theintensivecontrolofthepatient.1,9

Probe

passing

technique

Probe introduction should be performed withthe patient underanesthesiaaftertrachealintubation.1_{Probeshouldbe} lubricatedwithproperTEEgel(usuallylidocainegelor inti-matelubricant),andthestomachmaybepreviouslyemptied toenhancetheimages.1

Probepassingisoftenachallenge.Thetechniqueconsists ofproper lubrication of theprobe,passing it throughthe posteriororopharynxandelevatingthemandiblewiththe lefthand.Passingitthroughtheupperesophageal sphinc-teristheprocedurecriticaltimeinwhichthemostserious complicationsmayoccur.Theprobeshouldprogresstoward theesophaguswithoutresistance.6_{Incaseofresistance,this} usuallyoccursbecausetheprobe’stipislodgedinthe pyri-formsinus,epiglotticvallecula,posteriorpartofthetongue, oresophagealdiverticula.Theprobeshouldneverbeforced againstresistance,asitmayleadtocomplicationssuchas perforationandbleeding.1

Anothertechniquethat canbeusedistheprobe intro-ductionwiththehelpofalaryngoscope.Inthiscase, care shouldbetakenwiththehemodynamicstimulus triggered byasecondlaryngoscopy.1

The TEE examination allows intra- and extracardiac anatomicalanalysisofthegreatvesselsatthebase,analysis ofcongenitalheartdefects,andqualitativeandquantitative analysisofDopplerflow.1,3_{Acompleteintraoperative} exam-ination notonly characterizes the patient’s hemodynamic profile but may lead tochanges in the surgical approach in up to25% of the exams,in which changes such asthe presenceof apatentforamenovale(PFO), leftatrial(LA) thrombi,or atheromaplaquesin theascending aorta(Asc Ao).8

Theexaminations mustberecorded onadigital media forfurtheranalysisandmedicalreport.Thus,itispossible toanalyzethepatient’sevolutionbothintraoperativelyand postoperatively.6

Management

of

TEE

probe

The correct use of the multiplane TEE probe functions provides adequate acquisition of cardiac images during intraoperative examination. In addition, its proper han-dling reduces the incidence of stomach and esophageal complications.

Moving the probe in the caudal and cranial direction produces changes in the images in the inferiorand supe-riordirectionsof theheart, respectively (highesophagus: about20---25cm;mediumesophagus:about30---40cm; trans-gastric (TG):about 40---45cm;deepTG: about 45---50cm). Changestotherightorleftoftheheartcanbeobtainedby movingtheprobeclockwiseorcounterclockwise.Thebest alignmentoftheimagescanbeobtainedwiththeanterior or posterior movement ofthe probe, usinganteflexionor retroflexionwiththehelpofthelargerprobehandle.1 Multi-planeTEEprovidesfineadjustmentsintheinclinationangle oftheimageplane andconsequently allowsfor more pre-cise anatomicalanalysis. The angle mayrangefrom0◦ _to 180◦ _(Fig.2).1

Comprehensive

echocardiographic

examination

(LV),rightventricle(RV),andLVOTwithpartoftheAV.The evaluationof regionalLVfunction isimpaired bytheapex shortening(Fig.3A).

Mid-esophagealfour-chambercross-section

Advance the probe from the previous position (five-chamber)upto30---35cm.We candescribetheLV,RV,LA, RA,interatrialseptum(IAS),MV, andtricuspidvalve(TV). Thetrue(notshortened)apexmaybeexposedby retroflex-ingtheprobe.Itisoneofthemostusedviewsfordiagnosis (Fig.3B).

Mid-esophagealmitralcommissuralcross-section

Fromthepreviousposition(four-chamber),rotatetheprobe upto45---60◦_{.TheMVhasatypicalappearanceinthisimage} (segments P1---A2---P3), the section passes through the MV

commissuralaxis.Papillarymusclesandchordaetendineae are identified. Small manipulations of the probe in this imagemayprovideanatomicaldetailsandamorecomplete analysisoftheMV(Fig.3C).

Mid-esophagealtwo-chambercross-section

Fromthecommissuralview, rotatetheangle between60◦ and 90◦_{. LA, left atrial appendage (LAA), LV,and MV are} identified.Theanteriorandinferiorwallsareexposedand bothventricularandmitralvalvefunctioncanbeevaluated. Coronary venous sinus (CS) is seen onthe shortaxis, just abovetheLVbasalinferiorwall(Fig.3D).

Mid-esophageallongaxiscross-section

Inthetwo-chamberwindow,rotatetheangleto120◦_.LA,LV, LVOT,AV,proximalAscAo,CS,andMV(P2andA2segments)

arevisualized.Adjustmentsaremadetomaximizeand accu-ratelymeasuretheLVOTdiameter.TheLVanteroseptaland inferolateralmovementscanbeinvestigated(Fig.4A). Mid-esophagealaorticvalvelong-axiscross-section

The probe is retracted a few centimeters fromthe posi-tionofthelongaxis inthemid-esophagus.Maintainingan angle of120---140◦_{,the LVOT, AV,andproximalAscAo are} alignedand,fromthispoint,AVcanbeevaluatedandthe sinotubularandannulardiametersofAomeasured.Finding

Upperesophagealascendingaortashortaxis cross-section

FromtheAVlong axisview(120---140◦_),theprobeis with-drawnand,with90◦_{counterclockwiserotation,theimages} of Asc Ao short axis and superior vena cava (SVC) are obtained.Themainpulmonaryarterycanbeseenwith bifur-cation(proberotationtotheleft)andtherightpulmonary arterybranchcanbeseentoalargeextent(proberotation totheright).Itisagoodwindowtocheckpulmonaryartery catheterplacement(Fig.4D).

Mid-esophagealrightpulmonaryveincross-section

Fromtheprevious position(Asc Aoshortaxis) retractthe probebetween0◦_and60◦_{androtateitclockwise.Theright} upperpulmonaryvein(RUPV)andtherightlowerpulmonary vein(RLPV)arevisualized.The RUPVisshownwithaflow paralleltotheUS beamandcanbe evaluatedonDoppler mode.Occasionally,arightmiddlelobarpulmonaryveincan beviewedenteringtheLAbetweentheRUPVandRLPV ori-fices.Theevaluationofpulmonaryveinsisofspecialinterest incongenitaldiseases.

Mid-esophagealaorticvalveshortaxis cross-section

Fromthepreviouslydescribedview(rightpulmonaryvein) returntotheAointhescreen centerwitha counterclock-wise rotation of the probe. Advance to AV commissural leafletsat anapproximateangle of45◦_.Thegeneral mor-phologyofAV(numberofvalves,presenceofcalcifications, motion)is observed, besides determiningif thereis pres-ence of aortic stenosis by planimetry. Interatrial septum (IAS)bulgingcontinuouslyinthecardiaccyclebyhigh pres-surescanalsobeobservedinthis window(Fig.5A).From thisposition, the discreet withdrawal of the probe or its anteflexionalsodepictstheLAA.

Mid-esophagealrightventricleinflow-outflow cross-section

Figure3 (A)Mid-esophageal five-chambercross-section. (B)Mid-esophageal four-chamber cross-section. (C) Mid-esophageal commissuralcross-section.(D)Mid-esophagealtwo-chambercross-section.

Figure5 (A)Mid-esophagealaorticvalveshortaxiscross-section.(B)Mid-esophagealrightventricleinflow-outflowcross-section. (C)Mid-esophagealmodifiedbicavalcross-section.(D)Mid-esophagealbicavalcross-section.

when compared to the visualization of four chambers in themid-esophagusplaneforflowanalysisbyTVonDoppler mode.Thiswindowisalsousefulincongenitalheartdiseases andinthecorrectplacementofpulmonaryarterycatheter (Fig.5B).

Mid-esophagealmodifiedbicavalcross-section

FromtheRVITandRVOTwindow,withaclockwiserotation between50◦ _and70◦_{,TViscentralizedandLA,IAS,RAand} inferior vena cava (IVC)are visualized. It maybe an api-calwindowtoanalyzeeccentricregurgitantjetsbyTVon Dopplermode(Fig.5C).

Mid-esophagealbicavalcross-section

From the window previously described (modified bicaval) raisetheangularrotationto90---110◦ _{androtatetheprobe} clockwise. Structurestobe analyzed include LA,IAS, RA, SVC, IVC,and right atrial appendage (RAA).This visibility positionisespeciallyimportantforanalysisofPFOandIAS defectsandtodetectairwithintheatria,aswellastoassist inthedifficultpassageofthepulmonaryarterycatheterinto theRV(Fig.5D).

Mid-esophagealrightandleftpulmonaryveins cross-section

Inthebicavalpositioninthemid-esophagus(90---110◦₎ con-tinue to rotate the probe clockwise untilthe right upper pulmonary vein (RUPV) and right lower pulmonary vein

(RLPV) are visualized. When rotating the probe counter-clockwise,theRUPVandRLPVcanbevisualizedattheright endofthescreen,wheretheyarealignedparalleltotheUS soundbeam.Itis idealfor flow analysisonDopplermode (Fig.6A).

Mid-esophagealleftatrialappendagecross-section

Thiscross-sectionalviewisobtainedinthemid-esophagus with an angle between 90◦ _{and 110}◦_{, turning the probe} clockwise.The upper leftpulmonary vein(ULPV) is often visualized.Duetothecomplexandvariableanatomyofthe LAA,itsevaluationmustbedoneindifferentsections.Color DopplerandpulsatileDopplerareusefulmodalitiesof eval-uation,particularlyregardingtheLAAcontractilefunction (Fig.6B).

Transgastricbasalshortaxiscross-section

Figure6 (A) Upper-esophagealright andleft pulmonaryveinscross-section. (B)Mid-esophageal leftatrial appendage cross-section.(C)Transgastricbasalshortaxiscross-section.(D)Transgastricmid-papillaryshortaxiscross-section.

Transgastricmid-papillaryshortaxiscross-section

FromTG basal short axis cross-section, the probe should returntotheneutralposition, or beminimallyadvanced, maintaining the zero angulation. This cross-section is extremelyusefulinassessingandmonitoringthevolumeand sizeof regional andglobal LV function, aswell as assess-ingterritoriesirrigatedbytherightcoronary(RC),anterior descending (AD), and circumflex (Cx) arteries. In it, the anterior, inferior, inferolateral, anterolateral, and septal wallscanbeidentified,aswellasthepapillaryanterolateral andposteromedialmuscles(Fig.6D).

Transgastricapicalshortaxiscross-section

Maintaining contact with the gastric wall, the probe is slightly advanced and/or retroflexed from the TG mid-papillaryshortaxis,favoringthevisualizationoftheapical segmentsof the LVandRV (turning theprobeclockwise). Thiscross-sectionmaybedifficulttoobtainduetothe pos-siblelossofcontactbetweentheprobeandthegastricwall causedbyretroflexionoftheprobe(Fig.7A).

Transgastricrightventricularcross-section

ThisimageisobtainedatthesamelevelastheTGbasalshort axiscross-section,onlyturning theprobeclockwise.TVis visualizedonitsshortaxis.TheuseofcolorDopplerinthis cross-sectionmay helptocharacterize the TVregurgitant orifice(Fig.7B).

Transgastricrightventricularinflow-outflow cross-section

Thisimageisorthogonaltothatdescribedpreviously(simply rotatethetransducerby90◦_{).TheanteriorandposteriorTV} cuspsandleftandrightPVvalvesareusuallyvisualized.This cross-sectioncanbeusedtoalignthejetsinPVwiththeUS beamforuseinthecontinuousandpulsatileDopplermodes (Fig.7C).

Deeptransgastricfive-chambercross-section

This image is obtained by advancing the probe in the stomach,maintainingcontactwiththegastricwall(probe anteflexion).ItistheidealincidenceforDoppleranalysisof AV,LVOT,andoftenMV, asbloodflow isparalleltotheUS beam(Fig.7D).

Transgastrictwo-chambercross-section

This cross-sectionis obtained fromTG mid-papillaryshort axis,changingtheangleto90◦_{.Itallowsevaluationofthe} LVanteriorandinferiorwalls, aswell asthe entiremitral valveapparatus(MV,papillarymuscles,chordaetendineae). ItisalsopossibletovisualizetheLAandtheLAA(Fig.8A). Transgastriclongaxiscross-section

Figure7 (A)Transgastricapicalshortaxiscross-section.(B)Transgastricbasalrightventriclecross-section.(C)Transgastricright ventricleinflow-outflowcross-section.(D)Deeptransgastriccross-section.

arevisualized.BecauseLVOTandAVareparalleltotheUS beam,aDoppleranalysisispossible(Fig.8B).

Descendingaortalongandshortaxescross-section

Becausethedescendingaorta(DescAo)isadjacenttothe esophagusandstomach,theacquisitionofimagesissimple. FromTGmid-papillary shortaxis cross-section, theprobe shouldbe rotated at about 180◦_{, withslight adjustments} untiltheabdominalAo(belowthediaphragm)isvisualized, attheceliactrunklevel;theprobeisdrawnandthe trans-ducerangleismaintainedatzerodegreeandtheshortaxis isobtained; thelong axis is obtainedwiththe transducer angle at 90◦_{. Image qualitycan be improved by} decreas-ingthedepthandadjustingthegain.Becausethereareno internalanatomicalstructures inDescAo, thedescription of findingslocation is usually basedon thedistance from thefindingtothe incisorteeth.Anotherimportant factor intheDescAoevaluationisthehemiazygosveinpresence, whichdrains the posterior leftthorax,often visualized in themostdistalfieldoftheimage,joiningtheupperthorax totheazygosvein,whichdrainstherightthorax.The azy-gosvein,beingnormallyparalleltoAoanditswalls being contiguous,canoftenbeerroneouslyidentifiedasa dissect-ingaorticblade.ColorandpulsatileDoppleranalysiseasily differentiatesthearterialfromthevenousflow(Fig.8Cand D).

Upperesophagealaorticarchlongaxis cross-section

ThisimageisobtainedfromtheDescAoshortthoracicaxis; theprobeiswithdrawnuntilAobecomeselongatedandthe leftsubclavianarteryemergenceisvisualized.Thisposition indicates the end of the distal aortic arch. The probe is turned clockwise and it is possible tovisualize the mean aorticarchandtheleftinnominatevein.Becausetheleft sourcebronchusinterposesbetweentheesophagusandAo, itisusuallynotpossibletovisualizetheproximalaorticarch andthedistalAscAo(Fig.9A).

Upperesophagealaorticarchshortaxis cross-section

From the cross-section described above, the transducer angleisincreasedtoabout70---90◦_{toobtainthelongaxis.} ThepulmonaryarterytrunkandPVcanbevisualizedonthe long axis; it is possible toobtain Doppler measurements. Dueto Ao curvature, the right brachiocephalic trunk and leftcommoncarotidarterycanoften beidentifiedtothe rightonthemonitor(Fig.9B).

Mitral

valve

Introduction

Among the cardiac valves, MV has the most favorable anatomiccharacteristics for transesophagealexamination, asthenearfieldisclosetothetransducer,hastheLAasan ‘‘acousticwindow’’,andhasnocardiacstructurethatcan

becalcifiedand/orgenerationofacousticshadowbetween thetransduceranditsstructure11_(Fig.1).

DuringtheMVintraoperativeperiod,TEEisa fundamen-taltool,asitallowsthelesionidentificationandadetailed descriptionofitsmechanismandseverity,thushelpingthe surgicaldecisionmaking.11

Anatomyandnomenclature

WhenstudyingtheMVanatomyandfunction,themost cor-rect is that it is viewedas a valvecomplex composed of distinct anatomical structuresthat work in a coordinated wayforitscorrectfunctioning.12_{Themitralvalvecomplex,} or mitralvalve apparatus, iscomposed of mitralannulus, cusps, chordae tendineae,papillarymuscles, and theleft ventricularmusculature.12

Mitralannulus

The mitralannulusis aconnectivetissuestructure witha three-dimensional saddle-shaped complex structure. It is anteriorly relatedtotheaortic valveapparatus, joinsthe atriumandleftventricle,andreceivesalongitsperimeter theinsertionofthevalvularcusps.12

Mitralannulus has twomain axes,one anteroposterior (upperandshorter)andonecommissural(lowerandlonger). Theseaxesmayalsobereferredtoasanteroposteriorand anterolateral---posteromedial13_{(Fig.10AandB).}

Under the ventricular contraction action, the mitral annulus posteriorregion undergoes asignificant reduction ofitstotalarea,withreductionupto25%.Themitral annu-lusanteriorregionfoldsduringsystoleandfurtherdecreases theanteroposteriordiameter.13

Leaflets

(cusps)

The normal mitral valve complex is composed of two anterior and posterior leaflets.12,13 _{The anterior leaflet} is inserted into the anterior annulus, in a fibrous skele-ton region adjacent tothe aortic valve apparatus, called mitral-aortic intervalvular fibrosa (MAIVF). It occupies approximately 1/3 of the annular perimeter and 2/3 of its area. The posterior leaflet inserts into the posterior annulusandoccupies2/3ofitsperimeter,butcorresponds to only 1/3 of the annular area.13,14 _{The leaflets are in} a curved coaptation line along the intercommissural axis (anterolateral---posteromedial); innormal situations,there areapproximately1cmoftissueoverlap.12

MV leaflets were subdivided into distinct regions in ordertoimprovecommunicationamongmedicalteam mem-bers.Amongtheproposedschemes,wewilluseCarpentier nomenclature,10 _{whichisalsousedbyASEandSCA.}1

Figure9 (A)Upper-esophagealaorticarchlongaxiscross-section.(B)Upper-esophagealaorticarchshortaxiscross-section.

Figure 10 Mitral annulus assessment by three-dimensional echocardiography. (A) Anteroposterior diameter. (B) Anterolateral---posteromedialdiameter.Ao,aorticring;A,anterior;P,posterior;AL,anterolateral;PM,posteromedial.

anteriorregion(A1),amiddle region(A2),andaposterior region(A3).At theanterolateral and posteromedialends, two regions are defined as anterolateral commissure and posteromedialcommissure,respectively10_(Fig.11).

Papillarymuscles,chordae tendineae,andleft ventricle

The two papillary muscles (anterolateral and posterome-dial)supporttheleaflets,locatedparalleltotheventricular musculature.12 _{The anterolateral muscle generally arises} from the middle portion of the anterolateral LV wall, receivesvascularizationfromtheADandCxarterybranches. Theposteromedialpapillarymusclearisesfromthemiddle portionof theinferior wall,is exclusively vascularizedby the RCartery branch,which makesit more vulnerableto ischemicinsult.12

Thechordaetendineaeconnectboththepapillary mus-cles and ventricular musculature to the MV leaflets. The anterolateralpapillarymusclesupports,throughitscords, the A1/P1 segments and the anterolateral portionof the A2/P2 segments; the A2/P2 posteromedial portion and

the A3/P3 segments are supported by the posteromedial papillary12_(Fig.12).

Chordae tendineae are classically divided into first, second and third-order chordae. First-order chordae are connectedtothetipoftheleaflets,havingasaconsequence ofitsrupturethesystoliceversionofleaflets, echocardio-graphically known as flail.12,13 _{Second-order chordae are} connectedtothebase ofleafletsandareknownas struc-turalchordae;itispossibletoidentifytwotofourchordae thickerthantheothers.12,13_{Third-orderchordaeusually} con-nect the posterior MV leaflet to the left ventricle wall, havingrecognizedimportanceinarchitecturemaintenance andventricularperformance12 _(Fig.12).

Intraoperativemitralvalveechocardiographic examination

Figure11 Carpentiernomenclature:segments#1are antero-lateral,#3areposteromedial,and#2correspondtothevalve mid-portion.The anteriorandposteriorcommissuresarealso visualized.12

Figure12 Mitralsubvalvarapparatus,showing thechordae tendineaedistributionateachcusp.12

ofimageacquisitionandtrainingwerealsoadoptedbythe SBAforteachingandtraining.4

Didactically,wewilldescribetheMVsequential evalua-tionmethodthroughtheASE/ACS methodology,1 _{trying to} identify its different segments according to their clinical importance.It is known that its accuracy is variableand highlydependentontheexaminer’sexperience,as demon-stratedbyMahmoodetal.16 _{Ontheotherhand,theability} tolocalizeitspatiallyinthemitralapparatusanatomyusing two-dimensional(2D)examinationstillrequires fundamen-taltraining.

Mid-esophagealfive-chambercross-section

Withtheprobeinsertionatadepthofapproximately30cm, with multiplane angle rotation about 10◦_{, AV, LVOT, LV} (exceptitsapex),andA1---A2andP1---P2segmentsare visu-alized(Fig.3A).

Mid-esophagealfour-chambercross-section

The probe is insertedat a depth of approximately35cm, withmultiplaneanglerotationbetween10◦ _and20◦_,until MVcanbeclearlyvisualized.ThesegmentsA3---A2andP2---P1 areevident,aswellastheTVseptalandposteriorleaflets (Fig.3B).

Mid-esophagealcommissuralcross-section

With the probe in the four-chamber position, the multi-planar angle is advanced between 50◦ _{and 70}◦ _{and the} commissuralplanewillbevisualized.ThesegmentsP1,A2, and P3 will be visible from right to left, in addition to thepapillaryanterolateralandposteromedialmuscles.The probeisrotatedtotherightandtheimageplanewillpass throughthe entire extensionof the anteriorleaflet(right commissural:A1---A2---A3),aswellastheentireextensionof theposteriorleafletwhenrotatedtotheleft(left commis-sural:P1---P2---P3,Fig.3C).

Mid-esophagealtwo-chambercross-section

From the commissural plane, the multiplane angle is advancedbetween80◦_and100◦_{andtheimageplanecalled} two-chamber willappear. Fromright toleft,the MV seg-mentswillbeA1/A2/A3andP3(Figs.3Dand4A).

Transgastricbasalshortaxiscross-section

Thetransducer isadvancedtothestomach,withthe mul-tiplane angle between zero and 20◦_{, and a MV image is} obtainedwithafishmouthopeningandclosing.The ante-riorleafletappearstotheleftandtheposteriorleafletto theright;theposteromedialcommissureappearsnearthe transducerandtheanterolateralcommissuremoredistalto thetransducer(Fig.6C).

Three-dimensionalfrontalcross-section(faceview) MV apparatus 3D evaluation is useful for defining and locating the pathology, describing the pathophysiological mechanismanditsseverity,aswellasfacilitating communi-cationwiththeinterventionalsurgeonorcardiologist.1_With the evolution of surgical and percutaneous techniques of mitralapparatusrepairtherewasaneedforreal-timehigh qualityimages,whichisnowpossiblethankstothe techno-logicalevolutionofthematrixarrayandimagemanipulation softwares.17

Thecomplete3Dexaminationwillbetreatedinaspecific topic, but we will describe twomore representative and usefulintraoperativeimagingplans,whichmaybein real-timeorinmulti-beatacquisitions.

Leftatriumvieworsurgeon’sview

FromtheLAview,itispossibletoidentifyallthevalve seg-mentation,whichfacilitatesthetopographicdescriptionof apathologyandcommunicationwiththesurgicalteam.By convention,AVispositionedat12o’clockintheimageand LAAat9o’clock(Fig.13AandB).

Leftventricleview

Figure13 Mitralvalveviewinthree-dimensionalimage.(A)Mitralvalveindiastole.(B)Mitralvalveinsystole.

Figure14 Mitralvalveviewofleftventricleinthree-dimensionalimage.(A)Mitralvalveindiastole.(B)Mitralvalveinsystole.

atthetop,anterolateralcommissuretotheright,and pos-teromedialcommissuretotheleft(Fig.14AandB). 3DcolorDopplerechocardiography

Bymeansofmulti-beatacquisition,itispossibletoobtain volumetric images of the regurgitant jet and its relation withtheMVstructuresand3Devaluationofitsvarious com-ponents,whichallowstodemarcateitsexactlocationand quantitativeevaluationinspecificsoftware18_(Fig.15). Three-dimensionalquantitativeevaluationofmitral valve

Besidestheabilitytogeneraterealtime3Dimages, numer-oussoftwareweredevelopedwiththeabilitytogeneratea quantitativeanalysismodelfromspecificpointsmarkedon the3Dimageofthevalveapparatus.Amongthese,themost widely used and studied software are Mitral Valve Quan-tification --- MVQ (PhillipsHealthcare®, Inc.,Andover, MA) and4DMV---AssessmentSoftware(TomTecImagingSystems GmbH®,Munich,Germany).18_{Althoughreferencevaluesand} clinical usefulnessarestillin thevalidationstage, impor-tant knowledge has been accumulated regarding mitral valveapparatusremodelingindifferentpathophysiological states.18

Intraoperativeevaluationofmitralvalve

The evaluation objectives beforecardiopulmonary bypass aretodefinethemechanism,locatethelesion,estimateits severity,and identifyassociatedpathologies, suchas pul-monaryarterialhypertension,ventriculardysfunction,and tricuspidregurgitation.13 _{Itshouldbenoted,however,that} generalanesthesiasignificantlymodifiesthehemodynamic conditionsandoften decreasestheseverityof regurgitant valvelesions.13

Evaluationofannularmorphology

Figure15 Three-dimensionalcolorDopplerofmitralvalve.

Leafletsevaluation

MV diseases can be classified according to the leaflets motion,accordingtoCarpentier’sclassification.10,19

DiseasesareclassifiedastypeIifpresentingwithnormal leaflet motion, such as mitralregurgitation due to endo-carditisleadingtoleaflet perforation,congenitalcleftsor isolatedannular dilatation, in case of atrial fibrillation19_; type II if presenting with excessive leaflet motion, such as prolapse caused by fibroelastic deficiency or Barlow’s disease19_{;andtypeIIIwhenpresentingwitha} pathophysio-logicalmechanismthatcausesrestrictedleafletmotionand maybesubdividedintoIIIa,IIIb,andIIIc.The IIIasubtype correspondstorestrictioncausedbyshorteningandfusionof thesubvalvarapparatus,suchasinrheumaticheartdisease. TheIIIbandIIIcsubtypesrepresentrestrictionduetoleaflet tethering,asinfunctionalmitralregurgitation,withIIIb cor-respondingtosymmetricandIIIctoasymmetrictethering19 (Fig.16BandC).

MitralregurgitationcausedbytypeIIpathologiesin gen-eral produceregurgitant jetsin the opposite direction of thelesion;however,centraljetsmayoccurincaseofboth leafletsinvolvement.19

Type III pathologies, with restricted leaflet motion, usually produce regurgitant jets in the same direction as the leaflets, may be central in case of symmetrical involvement.19

Systolicanteriormotion

Systolicanteriormotion(SAM)ofMVhasbeenreportedafter valverepair,withan incidenceupto16%in patientswith myxomatousdisease.20 _{Itconsistsoftheanterior} displace-mentofthecoaptationpointandsubvalvulartissuetoward LVOT during systole, causes varying degrees of dynamic obstruction20_(Fig.17).

Notall SAM causesclinically relevant obstruction. It is traditionallydiagnosedinthepresenceofagradientacross theLVOTandmitralinsufficiency.20 _{Thepresenceofmitral} tissueacrosstheLVOTis oftenpossibletobeverified,but withoutanygradient,asituationclarifiedby3D/4DTEE.14 Theabilitytoechocardiographicallypredictwhichpatients areatgreatestriskforSAMdevelopmentaftermitralrepair isakeytaskofintraoperativeexamination.Inthelasttwo decades,somecriteriahavebeendefinedandvalidated.The mostrelevantonesarethefollowing:20---22

• Distance between coaptation point and septum (5-chamberlongaxis)<2.5cm;

• Posterior leaflet systolic length (5-chamber long axis) >1.5cm;

• Relationship between anterior/posterior systolic length (5-chamberlongaxis)<1.4cm;

• Smallventricularcavity---diastolicdiameter<4.5cm; • Interventricularseptum(IVS)bulging>1.5cm;

• Mitroaorticangle(3Dquantification)>65◦_atrestand>35◦ understress;

• Aortomitralangle(3Dquantification)<120◦_.

Figure17 Mitralvalveanteriorsystolicmotion.

Junction Sinotubular

Aortic ring

LVOT

Ascending

aorta

RVOT

LV

Figure18 Aorticcomplex.LV,leftventricle;LVOT,left ven-tricularoutflowtract;RVOT,rightventricularoutflowtract.

Leftventricularoutflowtract,aorticvalveand aorta

AVis a component ofthe aortic root, whichby definition extends from the basal aortic valve annulus to the sino-tubularjunction.WiththeassociationoftheLVOTinterval triangles,wewillhavetheso-calledaorticvalvecomplex23 (Fig. 18). Pathologies can occur not only in AV but also involveanycomponentsof thiscomplex,whichreinforces theimportanceofadetailed,hemodynamic,andanatomical evaluationofthisregion.1_{Withtheadventofnew} technolo-gies for treating aortic complex pathologies, therewas a greatadvanceintheunderstandingofitsanatomy;2Dand 3DDTEEstandoutinthedetailedmorphologicalevaluation oftheseanatomicalstructures.24

Anatomy

TheaorticvalvarcomplexisacontinuationoftheLVOTandis locatedtotherightandposteriortotheRVOT,withits poste-riormarginwedgedbetweenMVorificeandmuscularIVS.24 Itsbasalcircumferenceiscalledaorticannulusorbasalring (Fig. 18) and has an oval shape in most individuals.24---26

Figure 19 Mid-esophageal aortic valve short axis cross-section.NC,non-coronary;LC,leftcoronary;RC,rightcoronary.

Approximatelytwothirdsof thisbasal ring,where the AV valvesnadirsareinserted, areconnectedtothemuscular IVS and the remaining third is in contact with the mitral valveanteriorleaflet,representsthebaseofafibrous tri-angle between the non-coronary valves and left coronary artery(‘‘fima’’).

The aortic root extends from the aortic valves basal insertiontothesinotubularjunction,passesthroughthe Val-salvasinuses,fromwhere onthe upperborderofthe left andright coronarysinusesthecoronaryarteriesoriginate. Thus,AVis asemilunarvalvewiththreevalves,identified accordingtothepresenceorabsenceofacoronaryartery, whichoriginatesfromthecorrespondingsinus ofValsalva: leftcoronaryvalve,rightcoronaryvalve,andnon-coronary valve24_(Fig.19).

2DandDopplerimagingofaorticvalveandleft ventricularoutflowtract

ItsanatomicallocationclosetotheLA,whichisincontact with the esophagus in its mid-plane, provides a precise anatomicalimage,bothinshort(Fig.5A)andlongaxesviews (Fig.4B).24_{TheperpendicularcontactoftheUSbeamswith} thesenearfieldallowsustousethehighestavailable fre-quencies, with consequent detailed appreciation of their morphology.5 _{The use of zoom as a resource to increase} thedetailfordistanceand/ordiametersmeasurementscan further improve accuracy and is recommended (Fig. 20). TheDopplerbundlesperpendicularitywiththesestructures inthe mid-esophagusechocardiographic sectionsmakesit impossibletoaccuratelyassesstheflowvelocities.5_This lim-itationisovercomewithTGlongaxis(Fig.8B)anddeepTG sections(Fig.7D),inwhichtheparallelalignmentwiththe beamsallowsanaccurateassessement.5,27

Mid-esophagealaorticvalveshortaxis cross-section

LVO

T

Asc Ao

IVS

(basal)

RC leaflet

LVOT _{Diam 1.7 cm}

2.27 cm2 Area

LVOT

Figure 20 Mid-esophageal aortic valve long axis cross-section.LVOT,leftventricularoutflowtract;IVS, interventric-ularseptum;RC,rightcoronary;AscAo,ascendingaorta.

themostanteriorposition,non-coronaryvalveadjacentto theIAS,andleftcoronarycusppositionedlaterallytothe left(Fig.19).This cross-sectionpresentsexcellentspatial and temporal resolution, allowing a detailed view of the valveshapeand function, which is important toevaluate thevalvardysfunctionmechanisms.ColorDoppler flowme-try is applied to assess aortic regurgitation and the size, mechanism,andpositionoftheregurgitantorifice.28_Probe removaloranteflexioncandisplaytheleftcoronaryostium image,aswellasitsintroductionorretroflexioncanprovide animageoftheLVOTshortaxis.

Mid-esophageallongaxiscross-section

The multiplane angle is rotated to 120◦_{, from the} mid-esophagial four-chamber cross-section, and the basal portionofIVS,LVOT,aorticroot(aorticring,Valsalvasinus, andsinotubularjunction),andAscAoproximaltubular por-tionappearsontheright sideofthe image(Fig.20).Two AVvalvesare displayed,theright coronary isalways that mostdistaltothetransducerbecauseitis themost ante-rior.Theothercusppresentinthiscross-sectionmaybethe leftcoronary, or most often the non-coronary, depending onthe commissure positionbetween them and the exact locationof theimagingplate asit passes throughthe AV. Presenceof calcification, thickening, motion degree, and valveopening, aswell asitsanatomical relationship with adjacentstructures,suchascoronaryostiaandIVS,should beevaluated.Thebasalaorticringdiametermeasurement ismadeinthiscross-sectionusing2DTEE,preferablywith zoomimage, as the distance between the most ventricu-lar nadir of the right coronary valveand the base of the fibroustriangle(‘‘fima’’),contralateraland orthogonalto theaorticrootlongitudinalaxis,intheventricularsystole. Thismeasureisusuallysmallerthanthatofthecoronalaxis (onlyobtainedvia3DTEEortomography)duetothebasal ringovalshape. Thisevaluation accuracy isimportant for

hemodynamic measures of systolic volume and cardiac output,aswellasforpredictingthesizeof aortic, percu-taneous, or surgical prosthesesplaced in this region.27 _In addition,thediametersoftheothercomponentsofthe aor-tic root, as well asthat of Asc Ao, should be measured. In case of aortic stenosis, where there is proximal flow convergence, the LVOT diameter (located approximately 5mmbeforetheaorticring)shouldbeused---pulsed-Doppler sample volumeis placedinthesame sitetocalculate the systolicvolumeejection.29_{Inthiscross-section,the} perpen-dicularityoftheUSbeamincidenceinthisregionflowdoes not allow accurate velocity measurements with pulsatile and/or continuous Doppler.28 _{In contrast, color Doppler} measurements are useful and reliable, providing impor-tantinformation,suchas:turbulentflowregionswithLVOT obstructions; measurement of vena contracta regurgitant jet;andrelationbetweenregurgitantjetdiameterandLVOT diameter.28

Transgastriclongaxisanddeeptransgastric cross-sections

Thesecross-sectionsareessentialintheassessment, allow-ingaccuratealignmentofLVOTandAVflows,withreliable measurement of their velocities through continuous and pulsed Doppler modes, important for gradation of valvar and/orsubvalvularstenoses,regurgitantjets,and measure-mentofLVejectedsystolicvolume(Figs.7Dand8B).27,28

Inthiscross-section,evaluationsofanatomicalstructures lose spatial resolution because theyare distant from the focus and parallel to the US bundle, the complementary action of trangastriccross-sectionswithmid-oresophageal cross-sectionsisemphasizedinthecompleteassessmentof AVandLVOTandmeasurementofejectionsystolicvolume andcardiacoutput.

2DimagingandDopplerofascendingaorta

esophagus, the aortic arch appears in longitudinal view, due to its anatomical position at that level (Fig. 9A). If inthisplanetheangleisturnedtoapproximately90◦_,the leftsubclavianarteryexitcanbeevaluateand,turningthe probe tothe left, part of itsextension can be evaluated (Fig.9B).Withananti-clockwiserotation,thetwoother bra-chiocephalicvesselscanbeevaluate.Theinnominateartery viewisthemostdifficultbecauseitislocatedinablindspot wherethetracheainterposes.34 _{Theuse ofX-plane,} avail-able in 3D transducers,allows thethoracic Ao evaluation in both longitudinal andtransverse planessimultaneously, improvesthetimeneededforevaluation,andgeneratesan

Kidney

Art. Renal Aorta

Figure21 Renalarterycross-section.

Atherosclerotic plaques

Figure22 Atheromaplaquesindescendingaortashortaxis.

positiondefinition.

3Dimagingofaorticvalveandaorta

Holodiastolic reflux

Figure23 PulsedDopplerindescendingaortashowingaholodiastolicrefluxofsevereaorticregurgitation.

Volumetric capture

Figure 24 Three-dimensional volumetric analysis of aortic valve.

theoutcomeoftheseprocedures,asfarastwo-year mor-talityisconcerned,46,47_{andcouldonlybemeasuredwith3D} images(Fig.26),sincecalculationsusingthemathematical formulasof2Dechocardiographywereshown tobe signifi-cantlyinaccurate.26,48 _{The identification thatLVOT hasan} ellipticalshapeinmostpatientsincreasedtheimportance of 3D TEE due tothe inability of 2D echocardiography to performthese important measurements accurately.26 _The distantlocationfromthetransducerfocus,thedistal curva-ture,thethinthicknessoftheAVvalves,andtheartifacts resultingfromthereverberationandacousticshadowofthe existingcalcifications are some of the challenges for the acquisition of 3D echocardiographic imaging of the aortic root.26_{ColorDoppler3Dshouldalsobeusedtoevaluate} nor-malflowandabnormalities,allowtwo-dimensionalcutswith perfectspatialorientation,andtheoddanalysisofall abnor-malflow aspects,suchasmeasurement ofthe contracted veinarea,whichisimportanttoquantifytheseflows, with-outtheneedtoapplygeometricformulasthatareimprecise forthesituation.37

Pulmonary

valve

Anatomy

PVisathoracicanteriorstructurelocatedobliquelytothe plane oftheAV.49 _{It isasemilunarvalvecomprisingthree} valves denominated by their positions relative to the AV (left,right,andanterior).49_{UnlikePV,thereisnocontinuity} ofPVwiththecardiacfibrousskeletonorright atrioventricu-larvalve.49_{Becauseitsvalvesarethinandpoorlyechogenic} and becauseit is far fromthe transesophageal probe,PV evaluationusingTEEisgenerallydifficult.1

2DandDopplermodes

RVOT,PV,andpulmonaryarterydimensionsarebest evalu-atedthroughthecross-sectionalviewofthemid-esophageal RVinflowandoutflowtracts,inwhichtheUSbeamis per-pendiculartothesestructures(Fig.5B).49_{Theanteriorvalve} inthiscross-sectionistheonefurthestfromthetransducer, whereasthe oneclosest totheAVmay correspondtothe rightorleftvalve.Incaseswherethesesectionalviewisof poorquality,TGcross-sectionsoftheRVinflowandoutflow tracts, upper esophageal aortic arch shortaxis (Fig.9B), and mid-esophageal Asc Ao short and long axes (Fig. 4C and D) may be usedto supplement informationon struc-ture,dimensions,andfunctionofthepulmonaryvalveand artery.1

Transverse

Figure25 Three-dimensionalmultiplanarreconstructionofaorticvalve.

Sagittal

Coronal

Transverse

Multiplanar reconstruction

Aortic ring measurement

- Area - Perimeter - Diameter

Figure26 Multiplanarreconstructioninassessingaorticvalvearea.

3Dpulmonaryvalve

PV 3D images can be acquired on upper esophageal aor-ticarchshortaxisormid-esophagealaorticvalvelongaxis cross-sections after a slight rotation of the probe to the left.1,49

Multiplanar image

3G image

Figure27 Three-dimensionalimageofdescendingaortaatheroscleroticplaque.

Left

atrium

and

pulmonary

veins

Anatomy

Inrelationtotheribcage,theLAisthemostposterior cham-beroftheheart.Itislocatedveryclosetotheesophagus, separatedonlybythefibrouspericardium.51_Trachea bifur-cation,esophagus,andDescAoareimmediatelybehindthe LAposteriorwall.ThisLAproximitytotheesophagusisvery advantageousforTEE,asLAisusedasawindowtoobtainthe mid-transesophagealviews.1,51 _{Intheseviews,LAisalways} at thetop of the screen, closetothe US beam (Fig.1).1 InrelationtoRA,LAis moreposteriorandsuperiorandis separatedfromRAbyIAS.52

LAwallscanbedescribedassuperior,posterior,left lat-eral,septal(or medial),posterior---inferior,andanterior.53 LA anterior wall is behind the transverse sinus, that is, behindtheAoroot.CSgoesthroughtheposterior---inferior walloftheLA.LAwallsaremuscularanditsthicknessmay varyfrom1±0.5mm. Abnormal wallthickeningmay indi-catethepresenceofamuralthrombusorevenendocarditis. MitralannuluscalcificationmayextendtotheLAwalland makeitthicker.1,52

LAAisablindbottomstructurewithanaperturetoLA. InrelationtoLA,itis locatedlateralandsuperior andits tipisdirectedanteriorly, overlapspulmonary arterytrunk and left coronary artery.51 _{LAA has an average diameter} of10---24mm, but thisvalue mayvary. Comparedto RAA, LAAhasanarrowerorificethatfacilitatestheformationof thrombiinsituationsoflowbloodflowandinnon-sinus car-diacrhythms.51_{BetweenLAAandULPVthereisatriangular} foldoftheserouspericardiumcalledcoumadinridge,which whenprominent maybeconfusedwiththrombusor atrial mass(Fig.6B).

Accordingtotheblood flow,LAstartsatthevenoatrial junction and ends at the MV orifice. The four pulmonary veinsentertheposteriorpartoftheLA,theleftveinsare

locatedmoresuperiorthantherightveins.51_Therearetwo right(RUPVandRLPV)andtwoleftpulmonaryveins(LUPV and LLPV). The RUPV passes behindthe RA junctionwith SVCandtheRLPVpassesbehindtheintercavalarea.52_The right pulmonaryveinsorificesaredirectly adjacenttothe IAS plane. On the other hand, the left pulmonary veins arelocatedbetween LAAand DescAo, ULPVispositioned posteriorlysuperiortotheIAS,whereasLLPVispositioned posteriorlyinferior.52,54

Physiology

LAis notjustasimple blood-carryingcamera. Itresponds dynamically to its distention with the secretion of atrial natriureticpeptidesandparticipatesinthemanagementof bodyfluids.55_{LAalsofunctionsasabloodreservoirfromthe} pulmonaryveinsduringventricularsystoleand isovolumet-ricrelaxation.Duringdiastole,LAworksasbloodconduitto LV.Attheendofdiastole,atrialsystoleoccurs,contributing with15---30%ofthevolumetransferredtoLV.56 _BecauseLA is an LVcontinuumduringdiastole,changesin ventricular complianceaffectsthesizeandfunctionofLA.56,57

TheincreaseinLAisapredictorofcardiovascularadverse events, as well as the onset of atrial fibrillation, intrac-ardiac thrombi formation, and cerebrovascular accidents (Fig.28AandB).58_{Whenathromboembolicsourceis} inves-tigated, LAA is the first site to be evaluated; TEE has a sensitivity and specificity for thrombus diagnosis of 100% and99%,respectively.However,becausetheyaresmalland complexstructures,theycan beleftundiagnosedin some circumstances.59

2D

and

Doppler

imaging

of

left

atrium

and

left

atrial

appendage

AV

RV

Figure28 (A)Echocardiographicimageofleftatriumthrombus.(B)Thrombus.LA,leftatrium;RA,rightatrium;AV,aorticvalve; RV,rightventricle.

• Mid-esophagealfour-chamber(Fig.3B); • Mid-esophagealcommissural(Fig.3C); • Mid-esophagealtwo-chamber(Fig.3D); • Mid-esophagealleftatrialappendage(Fig.6B); • Mid-esophageallongaxis(Fig.4A);

• Mid-esophagealaorticvalveshortaxis(Fig.5A); • Mid-esophagealbicaval(Fig.5D);

• Transgastrictwo-chamber(Fig.8A); • Deeptransgastric(Fig.7D).

Thecross-sectionalimagesthatmosteasilyevaluatethe LAarethemid-esophagealones.LAisthestructureclosest totheUSbundleinthemid-esophageal views;itisalways foundatthetopofthescreen.TEEcross-sectionsthat eval-uateMVwillnecessarilyevaluateLA.1

LA evaluation starts from the mid-esophageal four-chamber view (Fig. 3B). Rotate the angle, going through theotherviewstoobtain2Dcross-sections.Intwo-chamber view (Fig. 3D), LAA image should be increased (Fig. 6B) to better visualize the presence of thrombi, particularly in riskpatients. Inbicavalview, the relationshipbetween LA and IAS and RA is evaluated, looking for PFOand IAS defects. In these cross-sections, the pulmonary veins will also be evaluated, as will be discussed below. After the esophageal evaluation,the transducer is advancedto the TGcross-sections. At the 90◦ _{angle, LA andespeciallyMV} anditssubvalvarapparatusareevaluated.IndeepTG cross-section (Fig. 7D),LAcan alsobevisualized, butthis view is more usedfor transaorticflow evaluation; LAis a sec-ondary evaluationbecauseit is furtheraway fromtheUS beam,withalowerresolutioncomparedtotransesophageal cross-sections.

DuetotheproximitybetweenLAandesophageal trans-ducer,LAcannotbeevaluatedinitsentiretybyasingleview, whichmakesitscomplete evaluationanditsdiameterand volumemeasurementsdifficultonTEE.1_{LAareaandvolume} maybeunderestimated.Thelinearmeasurementsacquired onTEEinmid-esophageal aorticvalvelongandshortaxes viewsaretheonesthatbestcorrelatewiththeTEE paraster-nallongaxiscross-sectionalmeasurement,whichmeasures LAin theanterior-posteriorsense.60 _{In longitudinalsense,} thevertexshouldbemeasuredfromsectortoAoroot,but thesemeasurementshavenonormalizedvalues. Septolat-eral measurements and LA volume can be obtained with mid-esophagealfour-andtwo-chambercross-sections. How-ever,thesemeasurements,althoughcorrelatedwiththose obtainedonTEE,havenonormalizedvalues.60

LAAevaluationmaybeinitiated withthefour-chamber cross-section, but because it is a lateral structure, the probeshouldberotatedcounterclockwise andanteflex to bringLAAtothe screen center.1 _{Alsoin thetwo-chamber} cross-section, LAA site can be zoomed in or the screen depth be reduced to evaluate LAA more accurately. An organized thrombus is echocardiographically defined as a well-circumscribed mass of uniform consistency and a texturedifferentfromthatoftheatrialwall(Fig.28).1 Spon-taneouscontrastis notwellcircumscribed, hasadynamic localization, and appears as a ‘‘cigarette smoke’’ --- this imageiscausedbytheslowingdownofbloodflow(Fig.29).61 Inhigh-risk patients for LAA thrombus(atrial fibrillation), theriskofthrombusformationshouldbeassessedthrough the analysis of blood flow velocity.61 _{Pulmonary Doppler} shouldbeplaced1---2cmfromLAAostium.Velocitieslower than27cm.s−1_{areassociatedwiththeformationof}

LA

LV

RV

Figure29 Mid-esophagealfour-chamber cross-section showing rheumatic mitralstenosis. Note thepresence ofspontaneous contrastinleftatriumandmitralvalveleafletsthickening.LA,leftatrium;LV,leftventricle;RV,rightventricle.Source:Personal collection.Yellowarrowindicatesmitralstenosis.Redarrowindicates‘‘cigarettesmoke’’inleftatrium.

2DandDopplerimagingofpulmonaryveins

ULPVisthemosteasilyfoundbyTEE.WhenLAAisfoundin the60◦_{mid-esophagealplane,theprobeisgentlyremoved} andULPVwillappearaboveandposterolateraltoLAAand tothecoumadinridge(anatomicvariantthatisoccasionally foundintheleftatrium)(Fig.6A).1

TheLLPVisthemostdifficultpulmonary veintoobtain onTEEimage.AftertheULPVimageisobtained,theangle is increasedto 90◦_{. The leftpulmonary veins will appear} asaninvertedV-shape.ColoredDopplerissettoavelocity of40cm.s−1_{andlaminarbloodflowisobservedtowardthe}

TEEtransducer.AnotherwaytoacquiretheLLPVimageis, afterfindingLAA,advancetheprobeandrotate itslightly clockwise and when LAA has disappeared, LLPV will be visible.1

RUPV is found with the mid-esophageal bicaval cross-section at 110---120◦_{, near the right pulmonary artery.}63 The angulation is returnedto 90◦_{, andthe tworight} pul-monary veins in inverted Y-shape can be evaluated. The rightpulmonaryveinscanbevisualizedatzerodegree mid-esophagealby rotating theprobe totheright so thatthe rightsideofLAliesinthecentralpartofthescreen.From thisposition,theangleisopenedto30◦_{andRUPVislocated} totherightofthescreenandRLPVtotheleftofthescreen, enteringperpendiculartoLA.63

Toassessthebloodflowpatternofpulmonaryveins,apply pulsedDopplerwithavelocitylimitof40cm.s−1_.Thenormal

flowpatternisthree-phasewithsystolic(S1 andS2), dias-tolic(D),andreverseatrial(A)waves.Diastolicdysfunction, mitraldiseases,andrhythmdisturbanceschangethisnormal pattern.1

Rightatrium,tricuspidvalveandvenous connections

RAistheheartcavitythatreceivessystemicvenousblood fromIVCandSVC,aswellasbloodreturningfromthe coro-naryarteriesthroughCS.Itsmedialandposteriorwallisthe IAS,thestructurethatseparatesitfromLA.Itsflooristhe TV, which opensinto theright ventricle.64 _{Seen from the} rightside,IAShasacharacteristicstructure,anovalfossa, whichshowsoutwardcontourandcentralregionconstituted bya delicateblade.This blademostanteriorportionmay notbe completelyadhered totheovalfossa edge,theso calledPFO.65 _{Necropsystudiessuggestthatitispresent in} upto27%ofadults.Itsinvivodiagnosisdependsondynamic evaluationwithmaneuversthatcauseincreasedRApressure concomitantwiththeinjectionofagitatedsalinesolution. Ahigherprevalencehasalsobeenassociatedwiththe pres-enceofIASaneurysm.65

TheLAlowerportionisseparatedfromLVbyaportionof fibroustissuethatcontinueswithIVS,calledfibrousseptum. This is due to the different levelsof implantation of the tricuspidand mitralvalves. TVhas moreapical insertion, whichresultsintheareaknownasatrioventricularseptum. CS outflow is located posteriorly and medially to the IVC ouflow next to the atrioventricular transition. In this region,remnantsofvenousvalvesmaybefound,withthe EustachiannexttoIVCandtheThebesianrelatedtoCS.64

mid-anteriorandinferiorportionsofIAS,correspondingto theovalfossaandseptumprimumregion.1

Fromthisposition,thetransducerisloweredtowardthe TGplanes,andtheangleismaintainedatzerodegree, even-tuallyaslightretroflectionoftheprobeisperformed,and alongitudinalimageoftheCSisacquired,alowerand pos-teriorstructure.1

Occasionally, CS can be assessed from the

mid-esophageal bicaval plane (Fig. 5D), with a discreet advancementandturningtheprobeclockwise.Stillin the bicavalplane(Fig.5D),SVC,IVC,Eustachianvalve, termi-nalcrest,andRAAareidentified.Fromthisview,theoval fossaisalsowelldefined,aswellasaPFOeventualblade. Adiscreetmovementoftheprobetowardtheupper esoph-agusallowsamorecompletepictureofSVC.Atthispoint, rotate theprobeclockwiseandthe rightupper andlower pulmonary veinswillbe visualized.Thus, thesuspicionof anomalousdrainageoftheseveinsistypicallyinvestigated fromthispointofview.1

By introducing the probe toward the TG planes from the bicaval plane and maintaining the angle at 90◦_{, IVC} and Eustachian valve can evaluated. Moreover, this posi-tionmaybeuseful toevaluate theimageofhepaticveins andtheirpossibleinadvertentcannulationduring cardiopul-monarybypass.1

Interatrialshuntdiagnosis

Insuspectedcasesofatrialseptaldefect,acomplete exam-inationshouldincludeacomprehensiveassessmentofIASin 2D mode and color Doppler, as defectsmay occur in any location.67

Assessmentofleftventricularsizeandfunction

The evaluation of LV size and function is an important componentofanyperioperativeechocardiographicexam.68 Thedegreeofventricularsystolicdysfunctionbesidesbeing a strong predictor of clinical outcome aids in the strat-ification of surgical risk and therapeutic interventions.68 Echocardiography providesa global andsegmental assess-mentofventricularperformancethroughanalysisofsystolic thickening, ventricularsize andvolume.69 _{Qualitative and} quantitativemeasurestoestimateventricularfunctioncan bemadethrough2D,3D,applicationofDopplerandby mea-surementsofmyocardialvelocityanddeformation.69

els:basal,atthemitralvalvelevel(sixsegments);medial,at thepapillarymusclelevel(sixsegments);andapical,after insertionofpapillarynervesuptotheendofthecavity(four segments),withthe17thsegmentlocatedatthetipofLV.30 TheTEEcross-sectionalimagerecommendedfor measure-mentofLVdiametersarethemid-esophagealtwo-chamber andlongaxisandtheTGtwo-chamber.Measurementisdone from the endocardium of the anterior wall to the endo-cardiumoftheinferiorwall,betweenthebasalandmedial thirdof the ventricle.The proposedview tomeasurethe left ventricular wall thickness is the TG mid-short axis30 (Fig.30).

2Dand3Dimagingofleftventricle

The assessment of leftventricular function and structure with 2D echocardiography uses five main cross-sections from mid-esophageal and TG planes, which are: mid-esophageal four-chamber, mid-esophageal two-chamber, mid-esophageal longitudinal, TG mid-short axis, and TG longitudinal.1,2_{Themostusedcross-sectionforLVsegmental} changesmonitoringistheTGmid-shortaxis,inwhichwecan visualizetheterritoriesirrigatedbythethreemaincoronary arteries2,6_{(Fig.31).TheanalysisofLVsegmentalfunctionis} basedonthevisualqualitativeevaluationofparietalmotion andsystolicthickening. Ideally, the function of each seg-mentshouldbeassessedthroughmultipleincidences.71 _LV parietalmotionfollowsthis recommendation:normal seg-ments,hypokineticsegments(mildtomoderatethickening), akineticsegments(withoutthickening),anddyskinetic seg-ments(paradoxicalsystolicmotion).2 _{Despitethe absence} of reference values and reproducibility below ideal, the quantitativeevaluationoftheregionalLVstrainmagnitude ispromising,mainlythroughthelongitudinal strainduring ventricularsystole.71

In order to improve the image quality for ventricular function correct quantification and interpretation, some technicalconsiderationsmust beobserved: correctimage depth adjustment to include the entire LV; avoid apical regionshorteningthroughpropermanipulationoftheprobe (anteflexionandretroflexion);correctidentificationofthe end of systole and diastole (check the motion of mitral andaortic valves,thelargestandsmallestcavitysizeand ECGsignal); correctDoppler alignmentwiththe direction of blood flow; appropriate gain and focus adjustment to improveendocardiumvisualization;anduseofsecond har-monicimage.72

A

B

C

Inferior Anterior

Sagittal Sagittal

Lateral inf. Inferior

Anterior

Figure30 Transgastriccross-sectionsforleftventricleassessment.(A)Mid-esophagealtwo-chamberview.(B)Transgastric two-chamberview.(C)Transgastricmid-papillaryshortaxisview.

Transverse mid-transgastric cross-section

DA CX RC

Figure31 Anatomic relationship and coronaryirrigation with left ventricle wallsin transgastric cross-section. DA, anterior descendingcoronaryartery;CX,circumflexcoronaryartery;RC,rightcoronaryartery.AdaptedfromGalhardoetal.6

ofleftventricularvolumeandfunction.7 _Ventricular func-tion analysis consists of using a software capable of semi-automaticallydetecttheendocardialedgeandmake more accurate volumetric calculations, which allows an accurate analysis of global and segmental LV function measurements, irrespective of the ventricle geometric shape and with better measurement replication among examiners.70,73

QuantificationofglobalLVsystolicfunction

One of the most routinely used methods in the operat-ingroomforglobalLVfunctionquantificationisqualitative or semi-quantitative, through which a visual estima-tion of the ventricular ejection fraction is made after the evaluation of multiple orthogonal cuts. This method has an acceptable correlation compared to quantitative measurements.74

Quantitatively,thesystolicventricularfunction estima-tionisevaluatedbyparametersthatmeasurethedifference between the final diastolic and systolic values related to leftventricularcavitydimension andvolumes.Among the quantitative methods, the most used in clinical practice have focused onmeasuringcardiac output, ejection frac-tion,shorteningfraction,fractionalareachange,ventricular performance index (Tei index),75,76 _{and on methods that} evaluatethevelocityandrangeof myocardialmotionand deformation(tissueDoppler,strainandstrainrate).3,77

Ventricularfunctionassessmentlimitations

The patient’s overall hemodynamic condition should be takenintoconsiderationduringventricularfunction assess-mentbecausechangesinbloodvolumeanduseofanesthetic drugsmayaffectsystolicfunctionbyitseffectsonpre-and post-load.Moreover,otherfactorsthatmaycompromisethe TEEfunctionevaluationarerelatedtoLVtipshorteningand exclusionintheevaluationofglobalandsegmental contrac-tilityanddifficultiesincorrectly aligningDopplertoblood flow,whichinterferesdirectlyinthecalculationof ventric-ularejectionrates.1

Right

ventricle

Anatomysystolicevaluationindexes