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REVIEW ARTICLE

Congenital Heart Disease in the Adult: A Review with

Internet-Accessible Transesophageal Echocardiographic

Images

Isobel A. Russell, MD, PhD FACC, Kathryn Rouine-Rapp, MD, Greg Stratmann, MD, andWanda C. Miller-Hance, MD FACC

Departments of Anesthesia and Perioperative Care, University of California, San Francisco, San Francisco, California;Departments of Pediatrics and Anesthesiology, Texas Childrens Hospital, Houston, Texas

The number of adults recognized with congenitalheart disease (CHD) has increased dramaticallyover the past five decades because of significant

advances in diagnosis and medical and surgical care.

At the moment, the population of adults with CHD(ACHD) in the United States is estimated at approxi-mately one million (1). For the first time, the numberof adults with congenital cardiovascular malforma-tions equals the number of children with these disor-ders. With additional refinements in surgical tech-niques and definitive repair at an earlier age, thispatient group is likely to increase even further.

Survival rates in CHD are influenced by many fac-tors, including year of birth, age at diagnosis, com-plexity of the pathology, and whether the lesion(s) has

been palliated or surgically corrected (Table 1) (1). Assurvival and life expectancy continue to improve, agrowing number of unoperated, palliated, and re-paired individuals require surgical interventions orother procedures related or unrelated to their heartdisease. The care of these patients is becoming morefrequent in all surgical settings, including tertiary carefacilities, ambulatory centers, and labor and deliverysuites.

Adults with CHD may come to the attention ofanesthesiologists for various indications including:

a. Cardiac surgery for the first time (for either pal-liation or definitive surgery)

b. Cardiac reoperation for further palliation or de-

finitive correction after palliative surgeryc. Cardiac surgery for management of residua, com-

plications of prior intervention, or conversion ofa priori repair to a modern, potentially more fa-vorable, strategy

d. Noncardiac surgery or other nonsurgical proce-dures in the presence of uncorrected, palliated, orcorrected lesions.

Anesthesia and surgery may carry an increased riskfor adverse events during emergent or elective proce-dures in these patients. This is particularly the case inthose with cyanosis, pulmonary hypertension, rhythmdisturbances, and significant hemodynamic abnor-malities. Recommendations from organizations suchas the American College of Cardiology (1) and theCanadian Cardiovascular Society (24) suggest thatthese patients should be cared for by cardiac anesthe-siologists who have specialized training or extensiveexperience in the field. However, anesthesia care pro-viders with such advanced expertise may not always

be available. The challenge in caring for these patients

is further magnified by the fact that there is a hetero-geneous population. Individuals may present at anytime with a bewildering array of structural variations,each with specific physiologic perturbations and he-modynamic consequences, and situations that requiresophisticated perioperative care. The spectrum ofCHD ranges widely from relatively mild defects seenin isolation to lesions of moderate to severe complex-ity typically characterized by several coexistent mal-formations. An important objective in caring forACHD is to diminish cardiac-related morbidity andavoid adverse perioperative events. Of utmost impor-tance in this mission is having a basic understandingof the native anatomy, physiology, surgical strategies,and late outcome of the defect under consideration.

The primary goal of this article is to present a gen-eral overview of the most common congenital cardio-vascular defects as applied to the adult age group,with a focus on anatomy, physiology, and long-termoutcome (Table 2). To facilitate this review, represen-tative images of the various congenital pathologies, asdisplayed by transesophageal echocardiography (TEE),accompany this contribution. The graphics are acces-sible as digital clips on the Web site of Anesthesia &

Analgesia (www.anesthesia-analgesia.org), and we

Supplemental data available at www.anesthesia-analgesia.org.Accepted for publication October 20, 2005.Address correspondence and reprint requests to Isobel A. Russell,

MD, PhD, FACC, Department of Anesthesia and Perioperative Care,521 Parnassus Avenue, San Francisco, CA 94143-0648. Addresse-mail to [email protected].

DOI: 10.1213/01.ane.0000197871.30775.2a

2006 by the International Anesthesia Research Society694 Anesth Analg 2006;102:694723 0003-2999/06


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hope the clips will serve as reference material for thoseinvolved in the care of these patients. The images arelabeled according to the American Society ofEchocardiography/Society of Cardiovascular Anes-thesiologists guidelines (5). We have made a signifi-cant effort to display most of the echocardiographicimages as obtained in the population of focus, theadult patient. This imaging modality has provided

significant contributions to the care of patients withstructural congenital cardiovascular pathology, andwe emphasize the benefits of this technology. The TEEimaging planes and information of interest for each ofthe lesions considered are listed in Table 3 as a guideto those who may want to become more familiar withthe applications of this imaging approach to CHD.Epicardial echocardiography contributed significantlyin the early experience of intraoperative imaging inpatients with CHD; however, it is used primarily inpatients when TEE is not feasible.

For an in-depth review of ACHD and the applica-tions of TEE in these patients, the reader is referred to

several comprehensive resources on the subject (611).The anesthestic considerations and management is-sues of CHD are beyond the scope of this article andhave been addressed elsewhere (1215).

We have divided this manuscript into a discussionof simple and complex lesions, with complex de-fined as the presence of more than one congenitalmalformation often requiring surgical intervention.

Simple Lesions

Atrial Septal Defects (ASD)

Anatomy and Physiology. Defects in the interatrialseptum or ASDs comprise 7%10% of all congenitalcardiac anomalies (16). These defects account fornearly a third of all structural defects detected inadults, occurring more commonly in female patientsthan in males (17). Although classification of ASDs isprimarily based on their location, characterization ofinteratrial communications is important in view of theincidence of associated anomalies and their impact onsurgical management. Several types of defects are rec-ognized including the following:

1) Ostium secundum or fossa ovalis defect (75% of

ASDs) is the result of a deficiency in the septum

in the region of the fossa ovalis (near or at themid-aspect of the interatrial septum). Varyingdegrees of mitral valve prolapse and/or mitralregurgitation can occur in the adult related tomyxomatous degeneration (1821).

2) Ostium primum defect (15% of ASDs), regarded asa form of atrioventricular septal (canal) defect,involves a deficiency in the inferior aspect of theinteratrial septum. Abnormalities of the atrioven-tricular valves occur most commonly in the formof a commissure or cleft in the anterior mitralleaflet potentially accompanied by variable de-grees of valvular regurgitation.

3) Sinus venosus defect (10% of ASDs) is usuallylocated in the superior aspect of the atrial sep-tum, inferior to the junction of the superior venacava and right atrium. This defect, also known assuperior vena cava-type of sinus venosus ASD, is

more common than its counterpart the inferiorvena cava-type of defect (located posteriorly atthe inferior vena to right atrial junction). Theseinteratrial communications are frequently associ-ated with anomalous pulmonary venous drain-age (80%90% of cases) from the right lung (22).

4) Coronary sinus defects (relatively rare) consist of acommunication between the left atrium andmouth of coronary sinus. These defects are com-monly associated with unroofing of the coronarysinus and a persistent left superior vena cava(LSVC) that drains directly into the left atrium(23,24).

Other entities that may not be routinely consideredin the classification of ASDs but may allow for inter-atrial shunting include a patent foramen ovale (PFO)at one end of the spectrum (25) and a confluent orcommon atrium at the other. Patency of the foramenovale has been reported in as many of 25% of pa-tients (26). In recent years, the presence of a PFO has

been associated with the pathogenesis of migraineheadaches (27,28). The potential for right-to-leftshunting allowed by an incompetent flap of thefossa ovalis may be a risk factor in some patients forparadoxical embolization and cerebrovascular mor-

bidity. A common atrium is characterized by com-plete or near-complete absence of the interatrial sep-tum and is seen most frequently within the contextof complex CHD.

A direct communication between the atrial cham-bers allows for pulmonary venous blood to enter theright atrium. The magnitude of interatrial shuntingrelates to the size of the defect, relative ventricularcompliances, and pulmonary artery pressures. A clin-ically significant defect results in right-sided volumeoverload characterized by right atrial, right ventricu-lar, and pulmonary artery dilation. The abnormally

increased pulmonary blood flow may be a long-term

Table 1. Survival Rate from Year of Birth (19402000) byComplexity of Congenital Heart Disease

Year of birth Simple Moderate Complex

19401959 90% 55% 10%19601979 95% 65% 50%

19801989 95% 90% 80%Adapted with permission from Tables 1, 2, and 3 of Care of the Adult with

Congenital Heart Disease. 32nd Bethesda Conference. J Am Coll Cardiol 2001;37:116198.

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Table 2. Congenital Heart Disease: Long term Outcome

AS Supravalvar AS usually progressive, AR can occur coronary ostial stenosis may be present systemic hypertension can develop

Valvar AS lifelong risk of endocarditis patients treated with valvotomy or valvuloplasty may have recurrent obstruction

requiring valve replacementBicuspid aortic valve

development or progression of AS, AR, aortic dissection or aneurysmal aortic rootdilatation

Subvalvar AS rate of progression variable associated with AR (60%) recurrence of fibromuscular subvalvular obstruction common (20% over a decade) tunnel like subvalvar LVOT obstruction has a high recurrence risk after repair, AR in 25% of patients

ASD Unrepaired eventually develop symptoms of dyspnea, fatigue, symptomatic supraventricular

dysrhythmias (atrial fibrillation, flutter sick sinus syndrome)Repaired near normal long term survival late atrial fibrillation in 1/3 patients, especially older than 40 years (Primum ASD discussed under AVSD)

AVSD Partial or intermediate forms presentation of unrepaired partial defect (ostium primum ASD and cleft mitral valve) in

adulthood not uncommon; most are symptomatic by 40 years of age in the short term, the results of surgical repair similar to those after closure of secundum

ASDs mitral valve regurgitation, sub AS and atrioventricular block may develop or progress occasionally mitral stenosis results, with surgical revision required in 5% to 10% of

patientsComplete forms

most presently corrected in infancy If prior palliation with pulmonary artery banding, may have resulted in inadequate

protection of pulmonary vascular bed uncorrected defect in the adult often associated with Eisenmengers syndrome first degree atrioventricular block is common and compelte atrioventricular block may

occur various degrees of sinus node dysfunction can occur long term results of surgical repair not well known, but problems likely similar to those

with partial AVSDCoA if untreated, systemic hypertension develops during childhood, with left ventricular

failure by the fifth decade death in untreated pathology usually due to: heart failure, aortic rupture and/or

dissection, infective endarteritis and/or endocarditis, cerebral hemorrhage, prematurecoronary artery disease

concommitant aortic valve disease (usually involving a bicuspid aortic valve)

endocarditis riskCoronary artery anom may go unsuspected until adulthood may present as syncope, myocardial ischemia or infarction or lead to sudden death

Corrected transposition median survival is 40 years in operated or unoperated patients who reach adulthood progressive systemic (tricuspid) valve regurgitation and systemic (right) ventricular

dysfunction occur from the 4th decade onwards atrial arrhythmias common from the 5th decade onwards atrial fibrillation common in operated patients and may be related to systemic (tricuspid)

AVV regurgitation high risk of congenital or acquired complete atrioventricular block

d-TGA arterial switch operation favored corrective procedure in the neonatal period overall survival in patients after older type of repair or atrial baffle (switch) procedure

approximately 65% at 25 years long-term morbidity of atrial switch operation related to sinus node dysfunction, atrial

dysrhymias, baffle obstruction, baffle leaks, tricuspid regurgitation and progressive right

ventricular dysfunction/failure(Table 2 continues)

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risk factor for the development of pulmonary vascularchanges in a small number of patients (5%10%). Sev-eral factors are considered in evaluating the need forintervention. These include the magnitude of theshunt or pulmonary flow (Qp) to systemic flow (Qs)ratio (also known as Qp:Qs) and concerns regardingthe potential detrimental effects of chronic right ven-tricular volume overload. Further factors that influ-ence the management approach include the presenceor potential for atrial arrhythmias, risks for the devel-opment of pulmonary hypertension, pulmonary vas-cular obstructive disease, paradoxical embolization,and right ventricular failure. It is important to recog-nize that physiologic changes in left ventricular com-pliance and aging may account for unfavorable in-creases in the degree of left-to-right shunting,exacerbation of symptomatology, and development ofright heart failure in the adult.

Long-Term Outcome. Primary suture or patch clo-sure of ASDs during childhood provides excellentoperative results and nearly normal long-term sur-vival (29,30). Surgical mortality is rare for isolatedsecundum defects in the current medical era. How-ever, an increased risk is recognized in older patients

and those with more than mild increases in pulmo-nary vascular resistance. As a rule, younger patientshave a better outlook after repair (2931). However,recent data have demonstrated that ASD closure is

beneficial even in patients older than 50 or 60 yr (32).Both retrospective studies and prospective clinical tri-als suggested improved 10-yr survival in patientsolder than the age of 40 yr treated surgically (95%)compared with those treated medically (84%)(30,33,34).

Atrial arrhythmias may be seen especially afterthe third decade of life. Late repair, after age 41 yr,

does not appear to reduce the incidence of rhythm

disorders (29). A management strategy that com-bined defect closure with arrhythmia surgery (Cox/Maze procedure) has been reported to be of benefitin these patients (35).

Closure of these defects by the transcatheter route isbecoming a widespread alternative to the surgical ap-proach (3639). Outcomes appear to be good, withsuccessful closure that is generally safe (40). Mini-mally invasive surgical techniques using a lateral tho-racotomy or limited sternotomy have been developedfor patients who are not candidates for interventionaldevice closure. This surgical approach has become an

attractive option for patients, with better postopera-tive recovery and improved cosmetic results (41,42).

The development of robotic techniques has helpedreduce both incision size and overall postoperativetrauma. Closure of ASDs has been performed via anendoscopic approach safely and effectively (43). In thisstudy, quality of life outcome measures were superiorin patients who received endoscopic surgery as com-pared with traditional sternotomy and mini-thoracot-omy; however, further outcome studies are needed toevaluate the safety and efficacy of this approach.

TEE. The identification and comprehensive char-acterization of ASDs by transthoracic echocardiogra-phy in the adult may be limited in some instances bypoor acoustic windows. Transesophageal evaluationshould be considered a complementary imaging mo-dality in ascertaining or confirming the presence, size,and location of the defect in these patients. The mid-esophageal (ME) four-chamber and bicaval views areparticularly useful in the examination of the atrialseptum by two-dimensional imaging and color Dopp-ler (Fig. 1 and Table 3) (see video clips 13 atwww.anesthesia-analgesia.org). Additional benefits ofthis technology include assessment of the severity ofassociated atrioventricular valve regurgitation, chamber

enlargement and ventricular function (transesophageal

Table 2. Continued

Large defect rare without pulmonary hypertension exists in adults only when associated with right ventricular outflow tract obstruction

Eisenmengers syndrome continuous risk of morbidity and mortality prognostic features include atrial flutter/fibrillation, syncope, heart failure, hemoptysis

and aneurysmal dilation of proximal hypertensive pulmonary arteries, which mayrupture

General points regarding VSDs 5% of patients develop AR (more likely to occur in association with doubly committed

subarterial (supracristal) defects from progressive aortic cusp prolapse) atrial fibrillation may occur late ventricular dysthythmias and sudden death are potential risks, especially in

patients repaired late in life endocarditis risk

Anom anomalies, AR aortic regurgitation, AS aortic stenosis, ASD atrial septal defect, AVSD atrioventricular septal defect, AVV atrioventricularvalve, CoA coarctation of the aorta, d-TGA d-transposition of the great arteries, LSVC left superior vena cava, LVOT left ventricular outflow tract, PDA patent ductus arteriosus, PS pulmonic stenosis, TOF tetralogy of Fallot, VSD ventricular septal defect.



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Table 3. Transesophageal Echocardiography (TEE) in the Evaluation of Congenital Heart Disease

Lesion Tee planes and information provided Postsurgical evaluation

AS ME AV SAXaortic valve morphology ME AV LAX and deep TG LAXvalve

morphology and motion, valvar regurgitation,

aortic root size, subaortic and supraaorticanatomy. Deep TG LAXpeak gradient acrossobstruction ME 4-CHLV hypertrophy and function

Residual/recurrent obstruction, aorticregurgitation, bioprosthetic/mechanical valve function, perivalvar

leak (if prosthetic valve), ventricularfunction

After Ross procedureaorticobstruction and regurgitation, functionof right ventricular homograft,ventricular function (global andsegmental)

ASD ME 4-CHsecundum and primum defects,pulmonary venous return, mitral valveanatomy (prolapse)

ME bicavalsinus venosus defect andpulmonary veins

Residual shunts, ventricular function Mitral regurgitation Obstruction of pulmonary veins (sinus

venosus ASD)

AVSD ME 4-CH and 2-CHmorphology of AVV,bridging leaflets and their attachments in thecomplete form of the defect, severity of AVVregurgitation. Size/location of intracardiacdefects.

Residual shunts, AVV regurgitation,LVOT obstruction, ventricular function

CoA UE Ao Arch SAX and LAX views ofdescending thoracic aorta and aortic arch (ifvisible)posterior shelf, aliased flow by colorDoppler and CW Doppler gradient of2.5meters/sec

ME 4-CH, 2-CH, AV LAX and TG SAXLVmass and function, mitral valve morphologyand function, aortic valve, subvalvular andsupravalvular obstruction

Residual gradient, recoartation, aorticaneurysm formation

Coronary artery anom ME AV SAX, AV LAX, and Asc AoSAXorigin and proximial course of coronaryarteries

ME 4-CH, 2-CH, LAX, TG SAXregional wallmotion abnormalities and biventricularfunction

SWMA and biventricular function

Corrected transposition ME 4-CH, 2-CH, TG mid SAXventricularmorphology and function, tricuspid valvefunction and associated lesions ME LAXRVOT obstruction

After double switch operation:Atrial baffle portion: baffle leaks,obstruction of venous pathways, AVVcompetence, function of systemicventricleArterial switch portion: outflowobstructionResidual intracardiac shunts

d-TGA ME 4CHAVV regurgitation associatedintracardiac shunts, ventricular function

ME bicavalsystemic and pulmonary venousbaffles

TG mid SAXventricular function and SWMA Deep TG LAXventriculoarterial connections

and arterial anastomes after arterial switch

After Senning/Mustard procedure:baffle leaks, obstruction of venouspathways, function of systemic (right)ventricle, AVV competence

After arterial switch operation:supravalvar (aortic/pulmonary)stenosis or regurgitation, LV function,residual shunts

Ebsteins Anomaly ME 4-CH, RV inflow-outflowtricuspid valvemorphology and degree of apical displacement,severity of tricuspid regurgitation, RA and RVsize and function, interatrial communication

Tricuspid regurgitation or stenosis,perivalvar leak (if prosthetic valve),RV size and function

LSVC ME 4-CH and 2-CHidentification of dilatedcoronary sinus. Agitated saline injection into aniv catheter in the left upper extremity, externalor internal jugular vein demonstrates contrastinto the coronary sinus and and right atrium

(Table 3 continues)



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and transgastric views). Concomitant defects such asanomalous pulmonary venous drainage can also be de-fined by a combination of imaging planes. TEE has beenshown to be of benefit during transcatheter closure byassisting in the selection of appropriate devices andmonitoring during placement (Fig. 2 and Table 3) (seevideo clips 4 and 5 at www.anesthesia-analgesia.org)(44). Intraoperative benefits during cardiac proceduresinclude documentation of the adequacy of the repair,exclusion of potential problems related to the interven-tion, and facilitation of cardiac de-airing. Obstruction tosystemic or pulmonary venous flow, as well as errone-ous diversion of systemic venous drainage to the leftatrium, can be recognized by TEE.

Color flow mapping contributes to the evaluation ofinteratrial shunting and atrioventricular valve compe-tency. Contrast echocardiography with agitated salinecan enhance the identification of small atrial level

shunts, as microbubbles are readily apparent in the

left atrium even when a very small number moveacross the defect (45,46).

Ventricular Septal Defects (VSD)

Anatomy and Physiology. VSDs are the most com-mon of all congenital cardiac anomalies, excluding a

bicuspid aortic valve. Epidemiologic studies suggestthat these defects account for nearly 30% (range, 16%50%) of all cases (47,48). Communications at the ven-tricular level can be found in isolation or may be seenin the context of other structural malformations.Adults with unoperated VSDs are encountered lessfrequently than are those with ASDs. Large defectsusually require surgical attention during childhoodfor symptomatology related to congestive heart failureor pulmonary hypertension. Although VSDs have amore frequent rate of spontaneous closure in children

(6), small perimembranous and trabecular muscular

Table 3. Continued

Lesion Tee planes and information provided Postsurgical evaluation

PDA Difficult to visualize by TEE, however ductalflow can be detected in the ME Asc Ao SAXview by presence of abnormal continuous high

velocity aliased flow

Persistant shunt, biventricular function

PS ME RV inflow-outflow and deep TG LAXoutflow tract evaluation and gradientestimation

ME Asc Ao SAXevaluation of pulmonicvalve, main pulmonary artery and proximalpulmonary artery branches

Residual pulmonary outflow tractobstruction, pulmonary regurgitation,RV size and function

Single ventricle ME 4-CH, 2-CH, LAX, bicaval, RVinflow-outflowAV valve morphology andatrioventricular and ventriculoarterialconnections

Post Fontan:Cavopulmonary connection, Fontanbaffle, aortic regurgitation, systemicoutflow tract obstruction, AVVcompetence, ventricular function,adequacy of ASD

TOF ME AV LAX and deep TGVSD and aorticoverride

ME RV inflow-outflowevaluation fo RVOTand estimation of gradient

ME 4-CHlocation and extension of VSD andother additional VSDs

Color Doppler in ME AV SAX and AV LAXevaluation of coronary artery anomalies

Residual RVOT obstruction, pulmonicor conduit stenosis, residual shunts,ventricular function, aorticregurgitation

Truncus Arteriosus ME 4-CHVSD location and extent ME AV SAXevaluation of truncal valve

morphology ME AV LAX and deep TG LAXevaluation of

truncal regurgitation and stenosis

Residual shunts, truncal stenosis orregurgitation, distal PA abnormalities,ventricular size and function

VSD ME 4-CH and AV LAXperimembranous,inlet and muscular VSDs, chamber sizes,presence of ventricular septal aneurysm

ME AV LAX and deep TG LAXevaluation ofaortic valve for regurgitation and herniation

Residual shunts, AVV and semilunarvalve competence and ventricularfunction

Anom anomalies, Ao aortic, AS aortic stenosis, Asc ascending, ASD atrial septal defect, AV aortic valve, AVSD atrioventricular septal defect,AVV atrioventricular valve, CH chamber, CoA coarctation of the aorta, CW continuous wave, d-TGA d-transposition of the great arteries, LAX long axis, LSVC left superior vena cava, LV left ventricle, LVOT left ventricular outflow tract, ME mid esophageal, PDA patent ductus arteriosus,PS pulmonic stenosis, RA right atrium, RV right ventricle, RVOT right ventricular outflow tract, SAX short axis, SWMA segmental wall motionabnormalities; TEE transesophageal echocardiography, TG transgastric, TOF tetralogy of Fallot, UE upper esophageal, VSD ventricular septal defect.



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defects may also completely close spontaneously evenin adulthood (6).

Various classification schemes have been proposedfor VSDs (11,49,50). The classification noted below offour major morphologic types is based on the ana-

tomic location of the defect. However, in some casesthe rims of the defect may extend beyond the marginof a particular region of the ventricular septum toanother.

1) Perimembranous defects, the most common type(70% of VSDs), are located in the membranousseptum, just inferior to the level of the aorticvalve. Frequently these defects are associatedwith tricuspid valve aneurysms or redundantseptal tricuspid valve tissue that may restrictflow through or completely occlude the defect.

2) Muscular defects (20% of VSDs) are located any-where within the trabecular component of the

ventricular septum, including the anterior andposterior portions and apical region. Multiple de-fects can occur, giving the appearance of a swisscheese septum, making surgical closurechallenging.

3) Doubly committed or subarterial (also known as supra-cristal) defects (5% of VSDs) are found in the re-gion that would normally correspond to the sub-pulmonary infundibulum. Fibrous continuity ofthe pulmonic and aortic valve is generallypresent. These defects may have associated aorticcusp deformity or herniation leading to aortic

regurgitation (51,52). This results from lack ofvalvular support by the outlet septum.4) Inlet defects (5% of VSDs) occur in the posterior

portion of the ventricular septum in close prox-imity to the atrioventricular valves. Associatedatrioventricular valve anomalies frequentlycoexist.

Defects that may be found in association with VSDsinclude a bicuspid aortic valve, aortic coarctation, andright ventricular outflow tract (RVOT) obstruction inthe form of pulmonic valve stenosis or anomalousright ventricular muscle bundles. An interventricularcommunication may also be present in complex formsof CHD and in certain types of single-ventricle typearrangements.

These intracardiac communications allow for shunt-ing at the ventricular level. The physiologic conse-quences of this lesion are determined by the size of thedefect, amount of shunting, and relative resistances ofthe pulmonary and systemic vascular beds. IsolatedVSDs are also classified in physiologic terms as either

shown in its short axis as it courses in perpendicular fashion behindthe superior vena cava. RPA right pulmonary artery; SVC

superior vena cava.

Figure 1. Atrial Septal Defects. Top: Secundum atrial septal defect.Mid-esophageal four-chamber view demonstrating the large inter-atrial communication, with superior and inferior rims of atrial sep-tal tissue bordering the centrally located defect. Color Dopplerinterrogation shows predominantly left-to-right shunting. RA right atrium; RV right ventricle. Middle: Primum atrial septaldefect. Left: Mid-esophageal four-chamber view showing the defectin the inferior aspect of the interatrial septum. Arrow indicates thelocation of the atrial septal defect. LA left atrium; LV leftventricle. Right: Color flow Doppler interrogation demonstratesatrial level left-to-right shunting through the atrial septal defect.Bottom: Sinus venosus atrial septal defect. Mid-esophageal bicavalview showing a large atrial communication at the superior aspect ofthe interatrial septum, underneath the entrance of the superior vena

cava into the right atrium. A dilated right pulmonary artery is



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pressure restrictive (right ventricular pressure lessthan left ventricular pressure) or nonrestrictive defects(equal or near-equal ventricular pressures). If the de-fect is restrictive the flow across it is usually limited.This is often the case with small defects. If the defect islarge and nonrestrictive the magnitude of the shunt isdependent on the ratio between the pulmonary andsystemic vascular resistances. A low pulmonary vas-cular resistance in the context of a nonrestrictive VSDleads to a large left-to-right shunt. The excessive pul-monary blood flow in turn results in increased leftventricular end-diastolic volume.

In addition to the classification of VSDs according totheir anatomic location or restrictive/nonrestrictivenature, characterization of this malformation in termsof size and likely hemodynamic significance is ex-tremely useful as follows:

Small Defect: pulmonary to systemic systolic pres-

sure ratio 0.3 and Qp:Qs 1.4 (53). The defectcauses negligible to minimal hemodynamicchanges. Normal right ventricular systolic pressure(RVSP), pulmonary vascular resistance, and leftventricular size are typically encountered.

Moderate Defect: pulmonary to systemic systolicpressure ratio more than 0.3 and Qp:Qs of 1.4 to 2.2(54). These lesions may be associated with volumeoverload and congestive symptoms. Some degree ofpulmonary hypertension is typically present, as areleft atrial and left ventricular dilation. These defectsare less common than smaller defects in the adult.

Large Defect: systolic pressure ratio more than 0.3

and Qp:Qs more than 2.2. In most patients a long-standing defect of this magnitude leads to the even-tual development of pulmonary vascular obstructivedisease (Eisenmengers syndrome, discussed subse-quently).

Long-Term Outcome. Surgical closure of VSDs early

in childhood results in excellent outcomes with sur-vival into adulthood generally without sequelae(55,56). Surgical intervention in older children may beassociated with reduced left ventricular function andincreased left ventricular mass (57).

Small interventricular communications, althoughregarded as hemodynamically insignificant, may not

be necessarily benign. This has led to continuing con-troversy regarding the need for surgical intervention.In a long-term follow-up of 188 adults with smalldefects, spontaneous closure occurred in 10% duringadult life; however, serious complications occurred in

25% of this cohort (53). These complications includedinfectious endocarditis (11%), progressive aortic re-gurgitation (5%), and symptomatic rhythm distur-

bances (8.5%), with atrial fibrillation being most com-mon (53). A number of individuals with moderatedefects may remain relatively asymptomatic untiladult life when gradual decompensation ensues re-lated to ventricular dilation.

New York Heart Association functional class morethan I, cardiomegaly, and an increased pulmonary arterysystolic pressure (50 mm Hg) are clinical predictors ofan adverse prognosis (17). Approximately 10% of pa-

tients with nonrestrictive VSDs develop Eisenmengers

Figure 2. Atrial Septal Defects. Device Closure. Left: Transcatheter closure of atrial septal defect. Foreshortened mid-esophageal four-chamberview obtained during transcatheter closure of a secundum atrial septal defect. The clamshell device (arrow) is noted to be in good position

in the interatrial septum. The legs of the device straddle both aspects of the interatrial septum. RA right atrium. Right: Dislodged clamshelloccluder device. Mid-esophageal four-chamber view with probe anteflexion shows an echogenic foreign body in the left ventricle.Embolization of the atrial septal defect occluder device (arrow) resulted in this being dislodged at the tips of the mitral valve leaflets. Thepatient required emergency surgery for device retrieval and closure of the interatrial communication. LA left atrium; LV left ventricle;RV right ventricle.



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syndrome, characterized by pulmonary vascular ob-structive disease and reversal in the direction of theventricular level shunt (6). These patients can surviveinto adulthood but typically have an overall decreasedsurvival rate.

The initial description of the clinical features ofwhat today is known as Eisenmengers syndrome wasmade in 1897 (58). Several years later the term Eisen-mengers complex was formally coined to includepulmonary hypertension at systemic levels related toincreased pulmonary vascular resistance, with re-versed or bidirectional shunting through a large VSD(59). This syndrome now describes the physiologyassociated with obliterative pulmonary vascularchanges and cyanosis related to a reversal in the di-rection of an intracardiac or arterial level shunt.

Morbidity in these patients relates to problems as-sociated with chronic cyanosis and erythrocytosis,

such as thromboembolic events, cerebrovascular com-plications, and the hyperviscosity syndrome. Othercomplications include hemoptysis, gout, cholelithiasis,hypertrophic osteoarthropathy, and decreased renalfunction.

The long-term prognosis for patients with this syn-drome is better than in those with other causes ofpulmonary vascular pathology, such as primary pul-monary hypertension (60). However, life expectancy issignificantly altered, with a reported survival rate of80% at 10 yr, 77% at 15 yr, and 42% at 25 yr (61).Variables associated with poor outcomes include syn-

cope, increased right ventricular end-diastolic pres-sure, and significant hypoxemia (systemic arterial ox-ygen saturation of85%) (61). Most patients succumbsuddenly, probably from ventricular arrhythmias. Pa-tients with Eisenmengers have undergone combinedheart and lung transplantation (62) and lung trans-plantation alone has evolved as an alternate therapy(63).

Surgical closure of VSDs is recommended if themagnitude of the increase in pulmonary vascular re-sistance is not prohibitive. However, if the ratio of thepulmonary to systemic vascular resistance exceeds 0.7,the risk associated with surgical intervention is signif-

icant. In a series of adult patients with VSDs, no post-operative problems were experienced if the restingpulmonary vascular resistance was 7.9 U/m2

(Woods units) (64). If postoperative pulmonary hyper-tension persists, the prognosis is unfavorable, withright ventricular failure occurring commonly (65,66).In patients with defects associated with aortic regur-gitation, late results after surgical closure of the defectand concomitant aortic valvuloplasty are generallygood. A survival rate of 96% at 10 yr has been reportedin young patients, with freedom from valvuloplastyfailure and freedom from reoperation documented to

be 76% and 85%, respectively, at 10 yr (67).

Transcatheter closure has been increasing in popu-larity (68) for both postoperative residual and muscu-lar VSDs (6971) with excellent closure rates and in-frequent mortality.

TEE. The role of TEE in the evaluation of patients

with VSDs has been well described (Table 3) (72,73).Transesophageal examination allows for definition ofthe location and size of the defect and determinationof chamber sizes and vessel dimensions, aids in thedetection of associated anomalies, and provides foridentification of ventricular septal aneurysms ifpresent, in addition to the assessment of the aorticvalve for herniation and/or regurgitation (74). Viewsthat allow for a comprehensive examination of theventricular septum include the ME four-chamber view(with sweeps that span from the anterior [outlet] to theposterior [inlet] aspects) and the transgastric (TG) midshort axis (SAX) view (Figs. 3 and 4 and Table 3) (see

video clips 6 9 at www.anesthesia-analgesia.org).Doppler color flow imaging allows for determinationof the direction and magnitude of the ventricularshunt and permits identification and quantitation ofassociated aortic regurgitation. Pulsed and continuouswave Doppler can be used to determine the peak flowvelocity across the VSD and to provide an estimate ofRVSP and pulmonary artery systolic pressure. In thepresence of restriction, the peak velocity across theVSD is high, consistent with a relatively high systolicpressure gradient across the ventricular chambers. Inthe absence of pulmonary outflow tract obstructionthe peak velocity across the VSD as determined by

spectral Doppler can be used to predict RVSP accord-ing to the modified Bernoulli equation as follows (75):

RVSP SBP 4 (peak velocity of VSD jet)2

where SBP systolic arterial blood pressure.In the presence of tricuspid regurgitation (TR), the

RVSP can also be estimated:

RSVP 4 (peak velocity of TR jet)2

right atrial pressure

During the surgical repair of VSDs or transcatheterclosure, TEE is able to provide guidance and detectresidual shunts by two-dimensional, color Doppler,and contrast imaging (68,7678). Further benefits in-clude evaluation of coexistent lesions, outflow ob-struction, valvular regurgitation and ventricularfunction.

Atrioventricular Septal Defects (AVSD)

Anatomy and Physiology. AVSDs, or canal defects,are characterized by abnormal endocardial cushiondevelopment, resulting in deficiency of the atrio-

ventricular septum and altered formation of the



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atrioventricular valves (79,80). In the complete formof this malformation there is an inferior interatrialcommunication or ostium primum defect, an inter-ventricular communication at the superior aspect ofthe inlet or posterior muscular septum and a com-mon atrioventricular valve. In the partial form, anostium primum ASD is accompanied by a cleft orcommissure in the left-sided atrioventricular valveand two functionally distinct atrioventricular valvu-lar orifices are generally identified. The prevalenceof these defects is frequent among patients with

Down syndrome.

Complete AVSDs are typically associated with non-restrictive intracardiac shunting, excessive pulmonary

blood flow, and excessive systemic pressures in theright ventricle and pulmonary artery. Without inter-vention this may result in early pulmonary vascular

changes and the development of fixed pulmonary vas-cular obstructive disease. The severity of atrioventric-ular valve regurgitation also influences the clinicalpresentation. Partial AVSDs are less likely to be asso-ciated with pulmonary overcirculation severe enoughto cause significant heart failure symptoms.

Long-Term Outcome. Most adults with the com-plete form of this defect have undergone completerepair in childhood. In some patients, initial palliationmay have consisted of pulmonary artery banding torestrict pulmonary blood flow, followed by subse-quent definite repair. Over the last several decades,the surgical approach has evolved from a two-stage

intervention to a single surgical strategy of primaryrepair in infancy (81). The long-term outlook afterrepair of AVSDs is good. In a few patients, uncor-rected defects have resulted in Eisenmengers physi-ology, rendering them inoperable candidates. This isassociated with significant late morbidity and earlydeath (61,82,83).

Although definitive repair is usually accomplishedduring childhood, various publications have docu-mented the results of surgical intervention in adultswith partial forms of defects. Patients older than 40 yrof age may undergo reparative surgery with low op-erative risk (84); however, they may require long-term

surveillance because late mitral valve dysfunctionmay occur. Among 50 patients who underwent sur-gery for partial AVSDs (mean age, 36.6 yr; 39 of them

being intervened for the first time for a substantialshunt), a low operative risk was reported and excel-lent long-term results were achieved (85).

Complications after repair of an AVSD include resid-ual intracardiac shunting, left atrioventricular valve ste-nosis or regurgitation, and subaortic obstruction.

TEE. In patients with AVSDs, TEE is useful inconfirming the anatomy and defining the type andextension of the septal defects (Table 3) (86). Two-and three-dimensional TEE imaging has beenshown to be of benefit preoperatively, not only dur-ing the initial repair but also when reinterventionshave been necessary (87,88). The deficiency in theatrial and ventricular septa and the large commonatrioventricular valve can be readily identified inthe ME four-chamber view (Fig. 5 and Table 3) (seevideo clip 10 at www.anesthesia-analgesia.org). Inthe complete form of the defect, characterization ofthe bridging leaflets, which span the commonorifice, assists in the classification of these defectsinto types A, B, or C as proposed by Rastelli et al.(79) according to the anterosuperior bridging leaflet

morphology. Other information of interest that is

Figure 3. Ventricular Septal Defects. Top: Perimembranous ventric-ular septal defect. Left: Mid-esophageal four-chamber view demon-strating a deficiency in the membranous septum consistent with aperimembranous ventricular septal defect. LA left atrium; LV left ventricle; RA right atrium; RV right ventricle. Right: ColorDoppler interrogation across the defect documents left-to-rightshunting. Bottom: Supracristal ventricular septal defect. Left: Mid-esophageal aortic long axis view showing a subarterial ventricularseptal defect. The close relationship of this defect to the semilunarvalves is noted. Right: Color Doppler demonstrates ventricular levelshunting.



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well outlined by TEE includes atrioventricular valve

competency, associated ventricular outflow obstruc-tion, and noninvasive assessment of pulmonary ar-tery pressures. In the postoperative patient, TEE canassist in the determination of residual defects, statusof the atrioventricular valves, and evaluation ofventricular function.

Pulmonic Valve Stenosis

Anatomy and Physiology. Although isolated valvu-lar pulmonic stenosis (PS), also known as pulmo-nary valve stenosis, is congenital in origin in mostcases, this pathology can be progressive. This lesion

accounts for 7%10% of patients with CHD. Findings

typically include systolic valvular doming, various de-

grees of leaflet tethering and thickening, and commis-sural fusion resulting in the formation of peripheral ra-phes and narrowing of the valve. In the uncomplicatedor pure form of PS the ventricular septum is intact. Aninteratrial communication in the form of a PFO or secun-dum ASD is often identified in this setting. In a fewpatients (approximately 20% of all cases), a variant char-acterized by valvular dysplasia is recognized (89). This isassociated with marked valvular thickening or mucoiddegeneration. Other less common forms of right ventric-ular outflow tract obstruction include infundibular orsubpulmonary obstruction, supravalvular stenosis, or

double-chambered right ventricle (characterized by the

Figure 4. Ventricular Septal Defects. Left: Muscular ventricular septal defect. Mid-esophageal four-chamber view post-cardiopulmonarybypass showing left-to-right shunting through a small residual muscular ventricular septal defect at the inferior aspect of the patch (arrow).LV left ventricle; RV right ventricle. Middle: Inlet/Muscular ventricular septal defect. Mid-esophageal four-chamber view demonstratinga large inlet muscular ventricular septal defect below the level of the atrioventricular valves. Right: Mid-esophageal four-chamber view withcolor flow Doppler showing left to right ventricular shunting.

Figure 5. Complete Atrioventricular Septal Defect. Left: Mid-esophageal four-chamber view demonstrating a complete atrioventricular septaldefect. The malformations characteristic of this lesion are shown, namely a primum atrial septal defect at the inferior aspect of the interatrialseptum (upper arrow) and the posteriorly located, inlet-type ventricular septal defect (indicated by the lower arrow). Bridging of the commonatrioventricular valve over the ventricular septum is seen. LA left atrium; LV left ventricle; RA right atrium; RV right ventricle.Right: Color flow Doppler showing extensive left-to-right atrial and ventricular level shunting.



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presence of anomalous muscle bundles within the tra-becular component of the right ventricle).

The magnitude of right ventricular outflow tractobstruction in patients with PS is directly related tothe degree of valvular narrowing. The obstruction to

pulmonary outflow imposes an afterload burden onthe right ventricle, resulting in right ventricular hy-pertrophy and decreased diastolic compliance. Thislesion is relatively well tolerated over time; however,severe right ventricular hypertrophy with increasedsystolic compression may lead to compromised intra-mural coronary flow. The increased right ventricularmyocardial oxygen demand may result in subendo-cardial ischemia.

Long-Term Outcome. Severe PS is unusual inadults. Generally, outcomes are excellent in patientswith this pathology and morbidity is relatively infre-quent. Right ventricular failure rarely occurs. Histori-

cally, surgical valvotomy has been extremely success-ful for long-term relief of the outflow obstruction. Anatural history study of surgically treated patients(peak systolic gradient exceeding 80 mm Hg) demon-strated an excellent 25-yr survival of 95%, equivalentto that of the normal population (90). In the adult,moderate to severe PS that would likely benefit fromintervention is generally defined by a peak transval-vular Doppler gradient more than 60 mm Hg, al-though intervention may be recommended for lesserdegrees of stenosis in the presence of symptoms. Inmost patients, percutaneous balloon valvuloplasty ishighly effective and considered the treatment of

choice, replacing surgical valvotomy in most cases(9194). Dysplastic valves have a less favorable re-sponse to catheter-based interventions. Consider-ations for reintervention include residual right ven-tricular outflow tract obstruction and progressivepulmonary regurgitation.

TEE. Two-dimensional imaging in the ME aorticvalve (AV) SAX and ME right ventricle (RV) inflow-outflow views demonstrates the stenotic, domingvalve leaflets in PS (Table 3) (95). The valvular orificecan range from a pinhole to several millimeters indiameter but is rarely critical in the adult. Pulmonaryregurgitation resulting from prior interventions mayalso be identified and qualitatively assessed in theseviews. On occasion, visualization of the pulmonicvalve can be challenging by TEE because of its distantanterior location relative to the probe position in theesophagus. Transgastric imaging may allow for fur-ther anatomic definition. An accurate measurement ofthe pressure gradient across the right ventricular out-flow tract is feasible with spectral (continuous wave)Doppler interrogation, usually from the ME ascendingaortic SAX and deep TG views. An interatrial commu-nication may be also identified by two-dimensional,color Doppler, or contrast imaging. A combination of

ME and TG views is useful for assessing the severity

of right ventricular hypertrophy and systolic function.Diastolic abnormalities associated with reduced ven-tricular compliance may be present in these patients,as documented by spectral Doppler interrogation (96).

Left Ventricular Outflow Tract ObstructionAnatomy and Physiology. Obstruction to left ven-

tricular outflow can occur at the level of the aorticvalve, above the valve (supravalvular), or below thevalve (subvalvular). This may take place in isolation oras part of complex CHD.

The bicuspid aortic valve is the most common valvu-lar anomaly and variant of congenital aortic valvestenosis. This is also reported to be the most frequentof all congenital cardiac malformations, occurring inapproximately 2% of the general population. The pa-thology is the result of commissural fusion leading to

the finding of a raphe or false commissure (Fig. 6and Table 3) (see video clip 11 at www.anesthesia-analgesia.org). Although this abnormality does notnecessarily imply valvular stenosis, it may be associ-ated with the development of progressive obstructionor regurgitation. A bicuspid aortic valve may be foundin asymptomatic individuals, either within the contextof associated left ventricular obstructive lesions or aspart of the spectrum of left ventricular hypoplasia. Theprevalence of associated defects is relatively frequent(up to 20%) and often includes patent ductus arterio-sus (PDA), aortic coarctation, VSD, and ascending aor-

topathy. Congenital valvular stenosis has a male pre-dominance and accounts for approximately 5% ofCHD.

Patients with severely malformed, stenotic valvesmay require intervention during childhood. Even witha less restricted orifice, the disturbed flow through thevalve causes progressive thickening and calcificationand may eventually result in severe stenosis and vary-ing degrees of valvular regurgitation that becomemanifest later in life.

In supravalvular aortic stenosis, the narrowing is typ-ically at the sinotubular junction (Fig. 7, left, and Table3) (see video clip 12 at www.anesthesia-analgesia.org).

The coronary arteries arise proximal to the area ofobstruction and are subjected to increased systolicpressures equal to that of the left ventricle. This maylead to coronary artery dilation and accelerated ath-erosclerosis. The arteriopathy found in these patientsmay also involve the origin of the coronary arteries orother systemic and pulmonary vessels. Diffuse nar-rowing of the abdominal aorta may occur in associa-tion with renal artery stenosis. This malformation isconsidered to be the result of a mutation or alterationof the elastin gene and may occur as part of Williamssyndrome (characterized by elfin facies, mental retar-

dation, idiopathic hypercalcemia, and other features).



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Subvalvular stenosis may take a variety of forms,including a discrete fibromuscular ridge or mem-

brane, a complex, tunnel-like obstruction, or hy-pertrophy of the interventricular septum as seen inhypertrophic cardiomyopathy (Fig. 7, right, and Ta-

ble 3) (see video clip 13 at www.anesthesia-analgesia.org). Discrete disease accounts for nearly10% of cases of aortic outflow obstruction. The shelfthat frequently encircles the outflow tract is consid-ered to be an acquired pathology as it is unusual ininfancy. A systolic jet develops that traumatizes thevalve leaflets and may lead to aortic regurgitation.Less common forms of subaortic obstruction, suchas complex tunnel-like narrowing, are observed in

association with other malformations that include

aortic valve stenosis, annular hypoplasia, and pos-terior malalignment of the ventricular septum (asmay be the case in patients with aortic arch inter-ruption). The association of left ventricular obstruc-tive lesions such as a bicuspid aortic valve, subaorticstenosis, aortic coarctation, and mitral valve abnor-malities that result in ventricular inflow obstruction(parachute mitral valve, supravalvular mitral ring)is known as Shones complex.

A common denominator among lesions that resultin impedance to left ventricular ejection includes apressure gradient across the obstruction and increaseof left ventricular systolic pressure. This results inincreased myocardial force and left ventricular wall

stress. With chronic obstruction, the hypertrophied

Figure 6. Left Ventricular Outflow Tract Obstruction. A. Bicuspid aortic valve. Left: Mid-esophageal aortic short-axis view showing thecalcified bicuspid valve in a diastolic frame. Ao aortic valve; RA right atrium; LA left atrium. Right: Mid-esophageal aortic long axisview of the stenotic, doming aortic valve. Ao aortic valve; LA left atrium; LVOT left ventricular outflow tract; RVOT rightventricular outflow tract.

Figure 7. Left Ventricular Outflow Tract Obstruction. Left: Supravalvular aortic stenosis. Mid-esophageal aortic long axis view in patient withsupravalvular aortic stenosis showing the classic hourglass appearance (noted by the arrows) corresponding to the area of narrowing abovethe sinotubular junction. The disturbed flow across this area is documented by color Doppler interrogation. Ao aortic valve; LVOT leftventricular outflow tract. Right: Subvalvular aortic stenosis. Mid-esophageal four-chamber view with anterior flexion demonstratingfibromuscular membranous ridge in the left ventricular outflow tract. RV right ventricle; LV left ventricle.



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myocardium may be at risk for the development ofsubendocardial ischemia as a consequence of an im-

balance in the ratio of myocardial oxygen supply anddemand. Factors such as increasing left ventricularafterload, inadequate hypertrophic remodeling, and

decreased myocardial systolic or diastolic perfor-mance may compromise stroke volume and contributeto cardiac dysfunction and heart failure in this setting.

Long-Term Outcome. Patients with a bicuspid aorticvalve may remain asymptomatic for many years butare at risk for developing endocarditis, aortic stenosis,or regurgitation. Approximately one fourth of patientsrequiring surgical intervention during childhood un-dergo reoperation for recurrent stenosis or progres-sive regurgitation within the following 25 yr (97). Withmedical treatment, approximately one third of chil-dren with systolic gradients less than 50 mm Hg andapproximately 80% of those with gradients 50 to 79

mm Hg need surgery within 25 yr (97). With symp-tomatic, hemodynamically significant valvular aorticstenosis (i.e., an aortic valve area 0.8 cm2) and aflexible noncalcified valve, balloon valvuloplasty mayhave therapeutic success similar to that of open val-votomy, even in young adults (98). In the adolescentand adult, a variety of surgical approaches has beenadvocated for management of valvular obstruction.These include valve repair/replacement with mechan-ical or bioprosthetic devices. The Ross proceduremight be favored in young patients because of growthpotential of the pulmonary autograft (neoaorta) (99101). Further advantages of this approach are that it

obviates the need for anticoagulation and its concom-itant potential morbidity. Short-term and midterm re-sults of the Ross procedure are encouraging, withmortality rates near 2% (102). Pulmonary homograftfailure (need for reoperation), dysfunction (mean gra-dient 40 mm Hg or more than moderate), and RVfailure can occur, as can aortic dilation with subse-quent regurgitation (103,104).

The management of discrete subaortic stenosis re-mains a challenge and the timing of surgery is contro-versial because of conflicting reports on mid- andlong-term survival (105). Data suggest that surgicalresection of the subaortic membrane before the devel-opment of a significant gradient (40 mm Hg) mayprevent recurrence, reoperation, and secondary pro-gressive aortic valve disease.

TEE. Transesophageal imaging and Doppler inter-rogation is particularly helpful in the assessment ofaortic valve morphology, measurement of annularsize and valve area, identification of post-stenotic di-lation of the ascending aorta, delineation of valvular,subvalvular, or supravalvular pathology, character-ization of the degree of ventricular hypertrophy andmyocardial function, and estimation of the pressuregradient across the obstruction (Figs. 6 and 7) (see

video clips 1113 at www.anesthesia-analgesia.org).

(106111). Continuous-wave Doppler interrogationacross the area of obstruction from the TG long axis(LAX) and deep TG LAX views provides for optimalalignment of the Doppler angle of incidence with theleft ventricular outflow and determination of accurategradients (112).

Evaluation of the repair, including function of aorticmechanical or bioprosthesis, paravalvular regurgita-tion, and pulmonary autograft, is facilitated by TEE(113115). The valuable contribution of TEE in adultpatients with suspected aortic valve vegetations androot abscesses has been documented (116). The use ofTEE during catheter interventions in aortic valve dis-ease has also been described (117).

Patent Ductus Arteriosus (PDA)

Anatomy and Physiology. The ductus arteriosus is avascular structure that connects the proximal descend-ing aorta to the pulmonary trunk. This communicationis an essential component of the fetal circulation, al-lowing for right ventricular output into the descend-ing aorta in the context of the typically elevated pul-monary vascular resistance. Persistent PDA accountsfor approximately 10% of cases of CHD. This lesionmay be found in isolation or in association with otherforms of heart disease (Fig. 8 and Table 3) (see videoclip 14 at www.anesthesia-analgesia.org).

The magnitude of left-to-right shunting in patientswith this defect depends on the size of the communi-cation and the pulmonary vascular resistance in amanner similar to that of a VSD. The physiologiceffects are those of increased pulmonary blood flowand left ventricular volume overload.

Long-Term Outcome. Patients with an inaudible (si-lent) or small PDA usually have normal life expect-

ancy. Survival to adulthood may be attributed to a

Figure 8. Patent Ductus Arteriosus. Mid-esophageal ascending aor-tic view showing continuous flow (arrow) between the aorta and

pulmonary artery. Ao

aorta; PA

pulmonary artery.



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relatively small left-to-right shunt and absence of pul-monary vascular changes. Most adults with hemody-namically significant communications eventually de-velop symptomatology characterized by dyspnea,atrial rhythm disturbances, and exercise intolerance

(118). Patients with this pathology can developmoderate-to-severe pulmonary hypertension. Theventricular volume overload can result in congestiveheart failure. Similar to the case of a large interven-tricular communication, the longstanding high pres-sure, high flow state can lead to increased pulmonaryarteriolar resistance and Eisenmengers physiology.There is a cumulative risk of endocarditis in patientswith PDA, particularly if the ductus is restrictive (119).

Traditionally, surgical closure of even small duc-tuses has been performed by ligation or division of theabnormal communication with the goal of preventinginfective endarteritis or endocarditis and the chronic

effects of ventricular volume overload. Some centershave described the use of a video-assisted thoraco-scopic approach and robotically assisted ductal clo-sure with good results (120122). The presence ofcalcification in the region of the ductus in older indi-viduals has been associated with a higher risk of com-plications. Percutaneous catheter closure using coils orintravascular occlusion devices is feasible in some pa-tients, with an approximately 95% success rate at in-termediate follow-up (123,124); data on long-termfollow-up are limited. Indications for intervention in-clude symptomatology related to the large left-to-rightshunt, particularly in the context of increased pulmo-

nary artery pressures, or symptoms consistent withsignificant ventricular volume overload. Test balloonocclusion has been advocated before definitive inter-vention in adult patients with increased pulmonaryartery pressures or vascular resistance.

TEE. Assessment of ductal patency is somewhatdifficult by two-dimensional transesophageal imagingalone. However, the diagnosis is facilitated by spectraland color Doppler interrogation of the pulmonaryartery and descending aorta. Color flow mapping inthe region of the distal main pulmonary artery in thepresence of a PDA demonstrates continuous, high-velocity aliased flow near the origin of the left pul-monary artery (Fig. 8) (see video clip 14 atwww.anesthesia-analgesia.org) (125127). SpectralDoppler interrogation documents the flow to extendinto diastole. A PDA may also be suggested by thepresence of diastolic flow reversal in the thoracicaorta. Contrast injection of agitated saline into a cen-tral vein while imaging the descending aorta by TEEmay demonstrate microcavitations distal to the levelof the left subclavian artery consistent with ductallevel right-to left shunting (128). The utility of TEE hasalso been described in the assessment of residual duc-tal shunting during catheter interventions and surgi-

cal closure (121,129 132).

Estimations of pulmonary artery pressures can beaccomplished by examining the regurgitant tricuspidor pulmonary velocity profiles or the flow across theductus (133). The pulmonary artery systolic pressure(PASP) can be calculated as follows:

PASP SBP 4v2

where v peak diastolic flow velocity across ductus.

Coarctation of the Aorta

Anatomy and Physiology. In this anomaly there isnarrowing of the aortic lumen in the thoracic regionimmediately distal to the origin of the left subclavianartery (Fig. 9 and Table 3) (see video clip 15 atwww.anesthesia-analgesia.org). In most cases, this pa-thology is congenital. This defect accounts for 5%8%of all congenital cardiovascular pathology.

The constriction in aortic coarctation may take theform of a discrete infolding-like posterior shelf or adiffuse hourglass narrowing of the distal arch in theregion of the ligamentum arteriosus. A long, nar-rowed aortic segment is often associated with hyp-oplasia of the transverse arch and aortic isthmus, inwhich case other structural cardiac malformationsmay also be present. Associated defects include a bi-cuspid aortic valve, VSD, mitral valve abnormalities,or various other types of left-sided obstructive lesions(6). This is not an uncommon presentation in earlyinfancy.

The hemodynamic repercussions of this lesion re-late to the obstruction to systemic blood flow. Arterialhypertension is usually present proximal to the aorticobstruction. Collateral circulation is typically seen

with longstanding pathology.

Figure 9. Coarctation of the Aorta. Long axis view of the descendingthoracic aorta showing the narrowing (arrow) that characterizes

aortic coarctation.



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Long-Term Outcome. The presence of symptoms as-

sociated with severe arch obstruction or concomitantcardiovascular defects leads to intervention in earlyinfancy and childhood. Adult patients with untreateddisease typically have a mild degree of obstruction.More than 80% of untreated patients do not survive

beyond the age of 50 yr (134). Morbidity and mortalityin the adult population with aortic coarctation areprimarily related to complications from associatedsystemic hypertension: ischemic cerebrovascular dis-ease, intracranial hemorrhage, myocardial infarction,congestive heart failure, or aortic rupture (134). Surgi-cal intervention has significantly improved survival,

but morbidity and mortality is still more frequent

compared with healthy adults because of persistentpostoperative systemic hypertension, accelerated cor-onary artery disease, and aortic dissection (135).

Intervention is usually undertaken when the coarc-tation is severe enough to cause proximal hyperten-sion and a gradient across the obstruction that exceeds25 to 30 mm Hg. Catheter techniques that include

balloon angioplasty, with and without stent implan-tation, have been shown to be effective in relieving theobstruction and normalizing arterial blood pressure insome patients (136). Aortic aneurysms can occuraround the area of coarctation or elsewhere in theaorta after angioplasty in 7%13% of adults (137).Stenting does not eliminate the risk of aneurysm, aor-tic rupture, or dissection, but it is unclear whetherthese risks are less with stent placement than with

balloon dilation alone (138). Various surgical tech-niques have been proposed for the management ofthis lesion, each with specific potential advantagesand disadvantages. Repair at an early age is advocatedin light of the low surgical risk in the younger agegroup and to minimize late morbidity. Surgery inadulthood can be complicated by the presence of mul-tiple collateral vessels (suggested on chest radiograph

by rib notching) and degenerative atheromatous

changes at the site of the coarctation. This accounts for

more frequent intraoperative mortality in adult

patients.TEE. It may be difficult to visualize the actual site

of coarctation by two-dimensional transesophagealimaging (Fig. 9) (see video clip 15 at anesthesia-analgesia.org). However, color Doppler interrogationof the descending aorta may facilitate this assessment

by identifying flow acceleration, turbulent jets, or apressure gradient, which continues into diastole (139).An associated bicuspid aortic valve may also be rec-ognized by TEE (140). Angiography, magnetic reso-nance imaging, or another imaging modality is usu-ally needed to define the site and extent of the aortic

narrowing (141).

Left Superior Vena Cava (LSVC)

Anatomy and Physiology. A persistent LSVC is aform of anomalous systemic venous drainage caused

by persistence of the embryonic left anterior cardinalvein. Autopsy studies have shown the frequency ofLSVC to be 0.3% (142). It occurs in 4.4% of patientswith CHD, most frequently in those with septal de-fects. Usually, the LSVC enters the heart through theorifice of an enlarged coronary sinus (Fig. 10 and

Table 3) (see video clips 16 and 17 at www.anesthesia-analgesia.org). Thus, when an enlarged coronary sinusis seen, a LSVC should be suspected. Other causes ofa dilated coronary sinus include TR with a jet directedat the mouth of the coronary sinus, right atrial hyper-tension, and, rarely, stenosis of the ostium of the cor-onary sinus.

In most cases of a persistent LSVC, a right superiorcava is present and may or may not communicate withthe left (via an innominate or bridging vein), but ab-sence of the right superior cava can occur (thoughrarely) (142). The confirmation of an LSVC to coronary

sinus is important because of the frequent associated

Figure 10. Left Superior Vena Cava. Left: Mid-esophageal four-chamber view showing a dilated coronary sinus (arrow) in short axis at thelevel of the mitral valve annulus. CS coronary sinus; LA left atrium; LV left ventricle; RV right ventricle. Middle: Mid-esophagealfour-chamber view showing a dilated coronary sinus (arrow) in long axis entering the right atrium. CS coronary sinus; LV left ventricle;RA right atrium; RV right ventricle. Right: Contrast injection through an IV catheter in the left arm demonstrates microbubbles enteringinto the right atrium via the left superior vena cava to the coronary sinus.



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malformations (143145) and is also relevant for pa-tients who may be candidates for single-ventricle pal-liation involving cavopulmonary connections (146). Inaddition, the presence of a persistent superior venacava may have several implications as follows: it may

confound the insertion of a pulmonary artery catheteror may interfere with the administration of retrogradecardioplegia (147).

Long-Term Outcome. In most cases, patients withan LSVC are asymptomatic but it is important to iden-tify the condition given its association with other car-diac lesions.

TEE. This anomaly is suspected in the presence ofa dilated coronary sinus identified in the four-chamber view as a large circular structure adjacent tothe lateral annulus of the mitral valve (Fig. 10) (seevideo clip 16 at www.anesthesia-analgesia.org) orseen as a posterior vessel entering the right atrium

(Fig. 10) (see video clip 17, left, at www.anesthesia-analgesia.org). A saline contrast injection into a leftarm IV catheter can be used to confirm the presence ofa LSVC (Fig. 10 and Table 3) (see video clip 17, right,at www.anesthesia-analgesia.org).

Complex Lesions

Tetralogy of Fallot (TOF)

Anatomy and Physiology. TOF is the most commoncyanotic lesion, accounting for approximately 10% of

congenital disease. This anomaly is characterized byfour anatomic features: right ventricular outflow tractobstruction, a VSD, right ventricular hypertrophy, andaortic override. Various levels of right ventricular out-flow tract obstruction are typically observed. Theseinclude infundibular or subpulmonary obstruction,valvular stenosis, and narrowing and/or hypoplasiaof the pulmonary annulus, main pulmonary trunk,and its branches. The subvalvular pulmonary obstruc-tion is the result of a displaced or anteriorly mala-ligned infundibular septum. This, in addition to theright ventricular hypertrophy, accounts for fixed, dy-namic, or combined subpulmonic obstruction. Thepulmonic valve is often bicuspid. The VSD is usuallylarge and nonrestrictive. Shunting across the VSD istypically in the right-to-left direction or bidirectional.Aortic override implies that the aorta is dextroposedlying directly above the level of the VSD.

Hypertrophy of the right ventricular myocardium isa compensatory response to the ventricular pressureload. The combination of the large, nonrestrictive VSDand the right ventricular obstruction results in an in-creased right ventricular systolic pressure similar tothe systemic arterial pressure. Increasing degrees ofright ventricular outflow tract obstruction or de-

creases in systemic vascular resistance are associated

with right-to-left intracardiac shunting, arterial de-saturation, and clinical cyanosis.

A number of tetralogy variants are recognized.These range from the pink form of tetralogy at oneend of the spectrum to complex defects such as pul-

monary atresia with VSD and absent pulmonary valvesyndrome. Pink tetralogy refers to a clinical settingwhere cyanosis is minimal as a result of a mild degreeof right ventricular obstruction. In severe forms oftetralogy the main pulmonary trunk or its branchesmay be significantly hypoplastic or even absent, as isthe case in pulmonary atresia. The pulmonary bloodflow in this setting is derived from aortopulmonarycollateral vessels.

Several associated cardiovascular anomalies havebeen described in patients with TOF. These include aninteratrial communication in the form of a PFO orASD (so-called pentalogy of Fallot, in 10% of cases),

additional VSDs, right aortic arch (in 25% of patients),aberrant origin and course of a subclavian artery, per-sistent connection between the LSVC and coronarysinus, coronary artery abnormalities, discontinuouspulmonary arteries, and AVSD.

Rarely, in adults with a perimembranous VSD, ac-quired hypertrophy of right ventricular muscle bun-dles may result in pathophysiology similar to that ofTOF.

Long-Term Outcome. Survival beyond childhood isunlikely in the majority of unoperated patients withTOF. Most patients with this anomaly have had pal-liative operations or corrective surgery by the time

they reach young adulthood. Before surgical interven-tion, most patients died in the second decade of life.Occasionally, an individual reaches the third decadeof life without surgery. Older age of repair is associ-ated with an increased risk of sudden death and atrialtachyarrhythmia (148). Rarely, patients present withonly palliative procedures aimed at increasing pulmo-nary blood flow.

Although a successful operation, definitive repair ofTOF may be associated with significant postoperativeresidua. In the past, corrective surgery was often ac-complished by a right ventriculotomy that facilitatedresection of the subpulmonary obstruction and closureof the VSD. One approach to address the right ven-tricular obstruction was placement of a large patchthat encompassed the subpulmonic region, valve an-nulus, and supravalvular region. This so calledtransannular patch was effective in relieving theobstruction; however, it invariably resulted in pulmo-nary regurgitation, which is progressive over time.Conditions that may require either catheter or surgicalintervention in the postoperative patient include re-sidual intracardiac shunting associated with hemody-namic burden, obstruction along the right ventricularoutflow tract or pulmonary bed, and pulmonary re-

gurgitation of significant severity. Aortic root dilation



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can eventually result in regurgitation and a need forsurgical intervention. In the early and intermediate

follow-up period, important residual right ventricularoutflow tract obstruction appears to be the majorsource of morbidity and mortality. However, in thelate follow-up period, pulmonary regurgitation witheventual right ventricular failure owing to volumeoverload and ventricular arrhythmias may lead todisability and even death. Survival in the postopera-tive patient with TOF is approximately 90% at approx-imately 30 yr after surgery (149). In a large series of163 patients who had undergone complete repair ofTOF (149), the 32-yr actuarial survival was 86% com-pared with a rate of 96% in a matched control popu-lation. Most adults with this lesion come to surgery for

correction of significant hemodynamic sequelae, espe-cially pulmonary outflow pathology and, less fre-quently, for residual intracardiac shunts. In adultswith repaired TOF and chronic pulmonary regurgita-tion, right ventricular dilation has been found to cor-relate with an increased incidence of sudden death(150). In a retrospective review of patients who hadpulmonic valve replacement to address regurgitationafter repair of TOF, it was noted that recovery of rightventricular systolic function may be compromised.Thus, it is recommended that intervention be consid-ered before ventricular function deteriorates. The per-formance of a palliative Blalock-Taussig shunt beforedefinitive repair, unlike the creation of other aorto-pulmonary artery connections, was not associatedwith reduced long-term survival. Independent nega-tive predictors of long-term survival included olderage at operation and a higher ratio of right-to-leftventricular systolic pressure after surgery. Rarely,adults with TOF present who have only undergone apalliative procedure designed to increase pulmonary

blood flow (e.g., Blalock-Taussig or other systemic topulmonary shunts).

In recognition of the long-term morbidity associatedwith significant pulmonary regurgitation, the surgical

strategy for this defect has undergone appraisal and

modification over the years. The current approachinvolves avoidance of an extensive ventriculotomy, if

feasible, limiting the infundibular incision and size ofthe transannular patch. Palliation versus definitivesurgery in early infancy is an issue of continuingdebate.

TEE. TEE is useful for definition of the pathology,which is best seen in the ME AV LAX (Fig. 11 andTable 3) (see video clips 1820 at www.anesthesia-analgesia.org). In patients with unrepaired TOF, TEEdemonstrates the nature and severity of the right ven-tricular outflow tract obstruction. The large VSD isreadily identified as is the overriding relationship ofthe aorta to the ventricular septum. Color-flow Dopp-ler interrogation is helpful in ascertaining the direc-tion of shunting across the ventricular septum and inthe exclusion of additional defects. The right ventric-ular outflow tract gradient can be quantitated by spec-tral Doppler on interrogation from the ME RV inflow-outflow views and main pulmonary artery, as theprobe is withdrawn slightly from the ME AV SAXview (5). Transgastric imaging adds to the anatomicand hemodynamic evaluation of the defects. The con-tribution of TEE during the surgical repair of TOF andits reliability in assessing the presence and severity ofresidual abnormalities has been documented(151,152).

d-Transposition of the Great Arteries (d-TGA)

Anatomy and Physiology. In d-TGA, the aorta arisesfrom the anatomic right ventricle and the pulmonaryartery from the anatomic left ventricle. The discordantventriculoarterial connection results in an abnormalrelation between great arteries. The most commonmorphologic arrangement is characterized by an aortaoriented in an anterior and rightward position withrespect to the pulmonary artery. This lesion accountsfor 5%7% of congenital cardiovascular malforma-

tions and is the most common form of cyanotic heart

Figure 11. Tetralogy of Fallot. Left: Unrepaired Tetralogy of Fallot. Mid-esophageal aortic long axis view demonstrating several of thecharacteristic features of tetralogy of Fallot: a large ventricular septal defect (arrow) and aortic override. Ao aorta; LA left atrium; LVOT left ventricular outflow tract; RVOT right ventricular outflow tract; VSD ventricular septal defect. Middle: Repaired Tetralogy ofFallot. Color Doppler interrogation in the mid-esophageal aortic long axis view after tetralogy of Fallot repair. The VSD patch is seen nearthe aortic valve (arrow) with residual right ventricular outflow obstruction and a residual VSD. A small pericardial effusion is noted. Ao aorta; LA left atrium; RVOT right ventricular outflow tract. Right: Repaired Tetralogy of Fallot with pulmonic insufficiency. ColorDoppler interrogation of the right ventricular outflow tract demonstrating at least moderate pulmonic regurgitation (arrow). RV rightventricle; PA pulmonary artery.



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disease identified in the neonate. Associated anoma-lies include a VSD (present in 20% of patients), leftventricular outflow tract obstruction, and coronaryartery anomalies.

In d-TGA the systemic and pulmonary circulations

function in parallel, rather than in series, resulting incyanosis. Without mixing at the atrial, ventricular, orductal level, this lesion is incompatible with life. Initialmanagement of profound hypoxemia in infants withd-TGA includes initiation of prostaglandin E1 therapyto maintain PDA and enhance intercirculatory mixing.The PFO may also require enlargement by balloonatrial septostomy.

Long-Term Outcome. Infants with this conditionrarely survive without intervention. Most young ado-lescents and adults have undergone definitive inter-vention during childhood. The standard surgical ap-proach for this condition several decades ago

consisted of an atrial baffle or redirection procedure(such as the Mustard or Senning operation). This al-lowed for systemic venous blood from the caval veinsto empty into the left ventricle and pulmonary arteryat the same time that the pulmonary venous bloodwas re-routed through the tricuspid valve into theright ventricle and aorta. The right ventricle remainedas the chamber ejecting into the systemic circulation.These physiologic corrections provided relief of cy-anosis and reasonably good survival (153). How-ever, a number of long-term complications have

been well documented in these patients, including

loss of sinus node function, atrial rhythm distur-bances, tricuspid regurgitation, eventual right ven-tricular dysfunction, and sudden death (7%) (154).Surveillance for the development of obstructionalong the venous pathways or baffle leaks is neces-sary in this patient group. The preferred approachfor d-TGA at the present time is the arterial switchoperation (Jatene procedure). This surgical strategyis designed to establish a normal, concordant rela-tion between the ventricular outflows and their re-spective great arteries, achieving anatomical correc-tion. The intervention involves transection of thearterial trunks above the level of the semilunar

valves, anastomotic connections to their appropriateoutflows, and translocation of the coronary arteriesto the neoaortic root. This restores normal physiol-ogy and also allows for the left ventricle to functionas the systemic pump. This operation can be per-formed in the neonatal period with relative lowmortality (3.5%) with infrequent need for surgicalreintervention (155). Long-term outcomes are gen-erally very favorable (156158). The need for thisprocedure to be performed early in life is based onthe principle that the left ventricle should be able tosupport the systemic circulation after the repair be-

cause it has been exposed to systemic pressures

during the prenatal/early neonatal period (as a re-sult of PDA).

TEE. Interrogation with multiple planes from thetransesophageal and transgastric windows in adultpatients who have undergone atrial baffle procedures

such as Mustard or Senning operations allows for theassessment of potential venous pathway obstructionand baffle leaks (Fig. 12 and Table 3) (see video clips21 and 22 at www.anesthesia-analgesia.org). Colorflow imaging along with injection of agitated salineinto a peripheral or central vein may assist in thedetection of residual intracardiac shunts or acquired

baffle leaks. Evaluation of right ventricular perfor-mance is relevant, as these patients are at risk forsystemic pump failure. Issues that merit attention inpatients with d-TGA after the arterial switch operationinclude neoaortic root dilation and associated regur-gitation, obstruction at the arterial anastomoses, andresidual intracardiac shunts. Other concerns relate tocoronary issues and their impact on global and seg-mental left ventricular function.

Congenitally Corrected TGA

Anatomy and Physiology. This malformation, alsoknown as l-TGA, is characterized by malposition ofthe great vessels and ventricular inversion. The struc-tural defects are the result of abnormal cardiac looping(l-looping) during embryonic development, resultingin atrioventricular and ventriculoarterial (double) dis-

cordance. The right atrium empties into an anatomicleft ventricle that then contracts into the pulmonictrunk. The left atrium is connected to the anatomicright ventricle that in turn ejects into the aorta. Theaorta is usually oriented in a leftward and anteriorposition in relation to the pulmonary artery. This pa-thology accounts for 1% all cases of CHD.

Cyanosis is typically absent because blood flows arephysiologically correct; however, an anatomic rightventricle functions as the systemic pump. Congeni-tally corrected transposition is frequently identified asa result of the manifestations of concomitant pathol-

ogy such as pulmonary outflow tract obstruction,VSD, or tricuspid valve abnormalities. Most previ-ously undiagnosed adults with this lesion usuallyhave either no other abnormalities or associated de-fects of mild hemodynamic consequence. In somecases, this lesion may remain undetected until thepatient presents with arrhythmias or syncope owingto complete atrioventricular block (159).

Long-Term Outcome. Without associated defects, pa-tients with corrected transposition may live for manyyears. The development of complete atrioventricular

block is common and occurs at a rate of approximately

5% per year in adults (160). Some patients, particularly at



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a young age, may be suitable candidates for surgicalintervention that restores the left ventricle as the sys-temic pump. This complex repair combines redirectionof the systemic and pulmonary venous flows in an atrial

baffle procedure with the arterial switch operation or avariation thereof (double switch operation). This strat-egy, however, may not impact mortality compared withconservative management (161).

Issues that require long-term surveillance in patientswith congenitally corrected transposition include rightventricular function and tricuspid valve competency.Late right ventricular systolic dysfunction and progres-sive TR culminating in heart failure are not uncommon

complications in patients with minimal or no associated

lesions. The survival of patients with this condition issubstantially reduced compared with age-matched indi-viduals (159,162,163).

TEE. The discordant cardiac relationships can bereadily identified by two-dimensional imaging(164). The ME four-chamber and TG mid SAX viewsare particularly helpful in

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