Eur J Echocardiography (2000) 1, 72–79doi:10.1053/euje.2000.0002, available online at http://www.idealibrary.com on

Rapid Diagnosis and Management of Thoracic AorticDissection and Intramural Haematoma: a Prospective

Study of Advantages of Multiplane vs. BiplaneTransoesophageal Echocardiography

M. Pepi*, J. Campodonico, C. Galli, G. Tamborini, P. Barbier, E. Doria,A. Maltagliati, M. Alimento and R. Spirito

Istituto di Cardiologia dell’Universita degli Studi, Fondazione �I. Monzino�, I.R.C.C.S., Centro di Studio per leRicerche Cardiovascolari del Consiglio Nazionale delle Ricerche, Milan, Italy

Aims: The purposes of this study were to compare theaccuracy of multiplane vs. biplane transoesophagealechocardiography (TEE) in the diagnosis of aortic dissec-tion and aortic intramural haematoma, and to test whetherthese techniques provide all the diagnostic informationrequired to make management decisions.

Methods and Results: Fifty-eight consecutive patientswith clinically suspected aortic dissection were studied withmultiplane TEE; all cases who required surgery underwentintraoperative monitoring with multiplane TEE.

The following multiplane TEE data were analysed: theangle between current and 0� plane at which each view wasobtained; the success rate in the evaluation of true and falselumen, entry tear, coronary artery involvement, aorticregurgitation, pericardial effusion. Advantages of multi-plane over biplane TEE have been evaluated by the dem-onstration of usefulness of views obtained in planes otherthan 0�–20� or 70�–110�, assuming that with manipulationof a biplane probe a 20� arc could be added to theconventional horizontal and vertical planes.

On the basis of TEE findings, aortic dissection wasconfirmed in 36 cases (18 type A, 12 type B, six intramural

1525-2167/00/010072+08 $35.00/0

haematoma). The specificity and sensitivity of TEE in termsof the presence or absence of aortic dissection or intramuralhaematoma were 100%. An additional clinical value ofmultiplane over biplane TEE in the evaluation of ascendingaorta, aortic arch, entry tears and coronary artery involve-ment was demonstrated. All cases with type A aorticdissection or intramural haematoma involving the ascend-ing aorta had an operation that was performed immediatelyafter the diagnosis (hospital mortality, 13%). Patients withtype B aortic dissection were treated medically; 25% ofthese cases were operated later (hospital mortality, 0%).

Conclusions: Multiplane and biplane TEE have excellentand similar accuracies in the evaluation of aortic dissectionand intramural haematoma. Multiplane TEE improves thevisualization of coronary arteries, aortic arch and entrytears; it appears to be an ideal method as the sole diagnosticapproach before surgery in type A aortic dissection.(Eur J Echocardiography 2000; 1: 72–79)� 2000 The European Society of Cardiology

Key Words: Aortic dissection, Aortic intramural hae-matoma; Multiplane transesophageal echocardiography.

Introduction

Transoesophageal echocardiography (TEE) is a usefultechnique for the rapid bedside evaluation of suspectedacute aortic dissection. The accuracy of monoplane TEEhas been well defined, and has been compared with othernon-invasive and invasive techniques[1,2]. More recently,

biplane and multiplane TEE have emerged as the newstandard techniques for ultrasound diagnosis of aorticdissection[3–5]; however, the diagnostic accuracy of bi-plane versus multiplane TEE for aortic dissection andintramural haematoma have not been well defined.Moreover, even though the rapid non-invasive diagnosisof aortic dissection and the avoidance of routine angi-ography appear to improve survival by expediting sur-gical intervention[6], the advantages and limitations ofmanaging patients on the basis of monoplane, biplane or

*Address for correspondence: Mauro Pepi, Istituto di Cardiologia,Via Parea 4, 20138 Milano, Italy.

� 2000 The European Society of Cardiology

Thoracic Aortic Dissection and Intramural Haematoma 73

multiplane TEE as the sole diagnostic investigation inpatients with suspected aortic dissection have not beencompletely demonstrated.

This study was undertaken to better define the role ofmultiplane versus biplane TEE in the diagnosis of aorticdissection and intramural haematoma, and to testwhether these techniques provide all the diagnosticinformation required to make management decisions inpatients with a suspected aortic dissection.

Methods

Fifty-eight consecutive patients (mean age: 61�12;range: 32–78 years) with clinically suspected aortic dis-section were admitted to our institute between 1995 and1998. All patients underwent initial screening with chestX-ray, transthoracic and TEE; TEE examinations wereperformed under haemodynamic monitoring in the car-diac or intensive care units. All cases requiring urgentsurgery underwent intraoperative monitoring throughmultiplane TEE.

For the TEE procedure in the awake patient, mildsedation with diazepam (2–5 mg) was used; the probewas inserted into the oesophagus after local anaesthesiawith 10% xylocaine spray and connected to the ultra-sound unit (Hewlett-Packard models 1500 and 5500,Andover, Mass., U.S.A.). For intraoperative TEE afterinduction of anaesthesia and endotracheal intubation, amultiplane probe was inserted in the oesophagus andconnected to the echocardiographic system (Hewlett-Packard model 1500).

We started systematic acquisition of cardiac imageswith the transducer initially located at the level of thegastric fundus, then at the lower oesophagus, followedby the upper esophagus; finally we evaluated thedescending aorta and distal aortic arch by rotatingthe probe posteriorly and laterally, and by moving theechoscope up and down. The diagnosis of aortic dissec-tion was made if two lumina, separated by an intimalflap, could be seen within the aorta. A tear was definedas a disruption in the continuity of the flap with flutter-ing of the ruptured intimal border, and/or as a highvelocity colour Doppler flow between the two lumens.

When the false lumen suggested thrombosis, centraldisplacement of the intimal calcifications was consideredto be indicative of dissection.

Dissections involving the ascending aorta were classi-fied as type A regardless of the site of primary fen-estration; all other dissections were defined as type B.Non-communicating intramural haematoma was de-fined as regional thickening of the aortic wall (>7 mm)in a circular or crescent shape and/or evidence of intra-mural accumulation of blood; exclusion of dissectingflap or intimal disruption was a prerequisite for thediagnosis of intramural haematoma.

The sequential introduction of a multiplane andbiplane probe in the same patient has not been carriedout because of practical and ethical aspects. Therefore,the advantages of multiplane over biplane TEE havebeen indirectly assumed by the demonstration of theusefulness of views obtained in planes other than 0�–20�or 70�–110�, as proposed by Tardif et al.[18].

All images were recorded on videotape andre-evaluated in the echocardiographic laboratory soonafter the examinations. We analysed the following:

(a) the angle between the current and 0� planeat which each view was obtained;

(b) the success rate (cases in which the correctanatomy was recorded/total examinations) in:

evaluation of ascending and descending aorta,aortic arch;true and false lumen and entry tear identifica-tion;coronary artery visualization and involvement;aortic regurgitation and its mechanisms;pericardial effusion;(c) additional clinical value (percent) was de-

fined as the percentage of cases in whichoblique views provided additional anatomi-cal informations compared to exclusivetransverse (0�–20�) or longitudinal (70�–110�) planes.

Table 1. Angles between current and 0� plane at which the short and the long axesof ascending, descending thoracic aorta and coronary arteries were obtained.

Mean angle (�)�SD

Minimumangle (�)

Maximumangle (�)

Ascending thoracic aorta (short) 42�21 0 61Ascending thoracic aorta (long) 123�9 80 160Descending thoracic aorta (short) 3�9 0 50Descending thoracic aorta (long) 92�10 68 130Aortic valve (short) 33�16 0 65Aortic valve (long) 122�20 78 165Left coronary artery (short) 32�15 20 74Left coronary artery (long) 104�10 100 120Right coronary artery (short) 54�12 0 60Right coronary artery (long) 107�7 98 115

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Contrast-enhanced computed tomography (22 cases),magnetic resonance imaging (one case) or aortograms(three cases) were performed in cases without TEE signsof aortic dissection in order to confirm the correctdiagnosis; intraoperative inspection of the aorta wasperformed in 18 cases who underwent urgent surgeryimmediately after TEE. The presence and extent ofintimal flap, the presence or absence of intimaltear, thrombus formation, intramural haematoma,aortic valve pathology and pericardial effusion weresystematically recorded on the operative reports.

Statistical Analysis

All values are expressed as mean�1 SD. The additionalclinical value (percent) of multiplane TEE was defined asthe percentage of cases in which oblique views wereessential in providing additional clinical informations in

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comparison to transverse or longitudinal planes. Com-parisons between groups were performed with theChi-squared test with continuity correction; a value ofP<0·05 was considered significant.

Results

On the basis of TEE findings, aortic dissection wasconfirmed in 36 out of 58 cases; 18 were classified as typeA, 12 as type B, and six as intramural haematoma(ascending aorta, four cases; aortic arch, one case;descending aorta, one case). No dissection was found in22 cases (two with normal aortic anatomy, 20 with aorticaneurysm). Diagnoses of aortic dissection or intramuralhaematoma by TEE were always confirmed by intra-operative findings of operations (22 cases), or by othertechniques (in 14 cases with type B dissection or intra-mural haematoma that were not considered suitable for

Table 2. Biplane (BTEE) versus multiplane (MTEE) transoesophageal echocardi-ography findings in aortic dissection and aortic haematoma.

Aortic dissection BTEE=30 pts MTEE=30 pts

Aortic length visualization (mm)Ascending 104 106Arch 45 46Descending 230 235

Intimal flap (%) 100 100True lumen (%) 100 100False lumen (%) 100 100Entry tear (%) 50 98*Mechanism of aortic insufficiency 90 100Pericardial effusion (%) 100 100Visualization of

Aortic Arch (%) 58 78Left coronary artery (%) 60 99*Right coronary artery (%) 48 90*

Aortic haematoma BTEE=6 pts MTEE=6 pts

Aortic wall thickening (mm) 8·3 7·8Haematoma extension (mm) 73 80Optimal anatomical definition (%) 66 100*

*MTEE vs BTEE, P<0·05.

Table 3. Additional clinical value (AV) of multiplane (MTEE) versus biplane(BTEE) transoesophageal echocardiography.

BTEE=30 pts MTEE=30 pts AV (%)

Aortic arch involvement 10/18 14/18 29Entry tear 15/30 28/30* 43Mechanism of aortic insufficiency 30/30 30/30 0Extension and anatomic definition of

intramural haematoma4/6 6/6 33

Coronary arteriesDissection 2/4 4/4 50No dissection 20/26 26/26* 23

*MTEE vs BTEE, P<0·05.

Thoracic Aortic Dissection and Intramural Haematoma 75

surgery). In cases without dissection at TEE, diagnoseswere always validated against computed tomography(22 cases), magnetic resonance (one case) and/or angiog-raphy (three cases); these techniques confirmed in allcases the absence of aortic dissection or intramuralhaematoma.

Thus, the specificity and sensitivity of TEE in termsof the presence or absence of aortic dissection orintramural haematoma were 100%.

Table 1 presents the mean angles at which each shortand long axis of the ascending aorta, descending aorta,aortic valve, left and right coronary arteries were visu-alized. This analysis demonstrates that the correct ana-tomical description of these structures was obtained inoblique planes. Consequently, optimal short and longaxis views of the ascending aorta were obtained in only24% and 19% by conventional horizontal and verticalbiplane views, whereas oblique multiplane TEE planesallowed the visualization of these views correctly in themajority of the study population (76% and 81% of cases,respectively).

Table 2 shows the main biplane and multiplane find-ings; aortic length evaluation by the two techniques wassimilar. Intimal flap, true and false lumen, aortic insuf-

ficiency and pericardial effusion were correctly identifiedin all cases by biplane and multiplane TEE. In contrast,multiplane TEE identified the entry tear in 98% of cases,whereas with biplane TEE it was identified in only 50%;moreover, the success rate in the visualization of theleft and right coronary arteries was higher throughmultiplane TEE.

Table 3 presents the additional clinical value of mul-tiplane vs. biplane TEE in patients with aortic dissec-tion. The anatomic definition of ascending aorta, aorticarch and coronary arteries was improved by multiplaneTEE; of 18 patients with proven aortic arch involve-ment, the dissection flap was clearly seen to extend to theaortic arch in 14 cases by multiplane TEE and in 10cases by biplane TEE. Of four cases with proven cor-onary artery involvement by surgery, biplane TEE failedto correctly visualize the coronary vessel in two, whilemultiplane TEE demonstrated coronary dissection in allcases; furthermore, multiplane TEE allowed the exclu-sion of the presence of coronary dissection in 26 cases,while for biplane TEE the figure was only 20 out of 26patients.

Examples of multiplane TEE demonstrating visualiza-tion of the entry tear, aortic intramural haematoma and

Figure 1. Aortic dissection (type A). Left panel: in the short axis at 52 degrees the true lumen (TL), falselumen (FL) and entry tear (arrow) are clearly shown. Right panel: long axis (122 degrees) of the ascendingaorta in the same patient.

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76 M. Pepi et al.

right coronary artery dissection are shown in Figures 1,2, 3 and 4, respectively.

No complications resulting from TEE occurred in thestudy population. The duration of the preoperative andintraoperative multiplane TEE were 15�4 min and22�4 min, respectively. All patients with type A aorticdissection or intramural haematoma involving theascending aorta had an operation that was performedimmediately after the diagnosis. In patients who had animmediate operation, the mean delay from admission tothe hospital to arrival in operating theatre was120�60 min. In all these patients the ascending aortawas replaced with a dacron graft; the aortic valve wasresuspended in two and replaced in four; arch replace-ment (three total; three hemi-arch) and the use of deephypothermic circulatory arrest were performed in sixcases. Coronary artery bypass grafting was required intwo cases. Hospital mortality among all 22 cases withurgent surgery was 13% (three patients). Patients withtype B aortic dissection or intramural haematoma lo-cated at the level of the descending aorta were treatedmedically; three of these cases were operated later due to

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associated complications. Hospital mortality in thisgroup was 0%.

Discussion

This study suggests that biplane and multiplane TEEhave excellent and similar accuracies in the diagnosis ofaortic dissection and aortic intramural haematoma; mul-tiplane TEE facilitates the correct alignment with trueshort and long axis of the ascending aorta, and improvesthe visualization of coronary arteries, aortic arch andentry tears. Multiplane TEE rapidly gives all the neces-sary diagnostic information required to make manage-ment decisions in patients with a suspected aorticdissection.

Our data confirm previous reports concerning theexcellent accuracy of TEE not only in the diagnosis ofaortic dissection, but also of intramural haematoma[5–9].The 100% sensitivity and 100% specificity of biplane andmultiplane TEE for both the presence and type of aorticdissection found in this study are findings in accordance

Figure 2. Intramural haematoma of the ascending aorta. Crescentic thickening of the aortic root andascending aorta is demonstrated in the short (left panel, 56�) and long axis (right panel, 130�) views.Morphology (C-shaped, thrombus-like echo-density) and extension (propagation for several centimetres toinvolve the entire ascending aorta) of the pathology are clearly visualized. LA, left atrium; AO, aorta; PA,pulmonary artery.

Thoracic Aortic Dissection and Intramural Haematoma 77

with recent data by other groups[5]; this contrasts withother studies[9–11] which showed that TEE has an excel-lent sensitivity to detect aortic dissection associated witha low specificity due a high percentage of false positivediagnoses. It is probable that the higher sensitivity andspecificity in our study, in comparison with previousreports, are mainly dependent on the technique utilized(the previous studies utilized mono- or biplane TEE);these observations reinforce the importance of a correctalignment with the ideal short and long axes of theaorta, something which is provided by multiplane TEE.Moreover, Evangelista et al.[12] demonstrated thatspecificity is highly dependent on the recognition ofartifacts, particularly at the level of the ascending aorta;assessment of the location and mobility of intraluminalimages by M-mode echocardiography (derived frombiplanar TEE) definitely improve diagnostic accuracy.In the present study we routinely utilized M-mode andM-mode colour Doppler echocardiography under two-dimensional control; multiplane TEE allowed us toobtain in each case the ideal long axis of the ascendingaorta and to distinguish artifact patterns (from theposterior aortic wall) from the true intimal flap.

Even though biplane and multiplane TEE have simi-lar accuracy in the diagnosis of aortic dissection, our

study demonstrates that in comparison with biplaneTEE, multiplane TEE facilitates the recognition of cor-onary arteries (proximal segments) and coronary arteryinvolvement, aortic arch and entry tears. These data arein accordance with reports on multiplane TEE whichshowed that structures with a complex spatial orienta-tion such as aortic valve, ascending aorta, aortic arch,and coronary arteries are more easily and completelyassessed with multiplane TEE[7,13–18]. Thus, multiplaneTEE appears to be an ideal method to give detailedanatomical information about the morphology of adissection, and can also show the consequences andcomplications of proximal extension.

As a potential precursor of aortic dissection, intramu-ral haematoma requires careful diagnostic attentionthrough the use of high-resolution tomographic imagingsuch as X-ray computed tomography, magnetic reso-nance or TEE; angiography is not diagnostic in thisdisease. Our study clearly shows that in a consecutiveseries of patients with suspected aortic dissection, mul-tiplane TEE correctly identifies all cases with intramuralhaematoma of the ascending (four cases), arch (onecase) or descending (one case) thoracic aorta. Keren etal.[5] demonstrated similar accuracy (90% sensitivity;99% specificity) in a large series of patients by using

Figure 3. Intramural haematoma of the ascending aorta. Thickening (2 cm) of the posterior aortic wall andintramural haemorrhage (arrows) are well defined at 115 degrees. LA, left atrium; AO, aorta.

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biplane or multiplane TEE. However, the possibility offalse-positive and false-negative TEE diagnosis of intra-mural haematoma has recently been described[19,20]; inparticular, differentiation from severe atherosclerosiswith local thickening or from periaortic fat may bedifficult, and alternative imaging procedures mayenhance diagnostic accuracy in selected cases. Eventhough the precise incidence of non-communicatingintramural haematoma is unknown, the percentage ofcases in our series (16%) is similar to that indicated inthe literature (5%–13%)[21,22]. Of the four cases in ourpopulation with ascending aorta involvement, one hada cardiogenic shock and another had severe hypo-tension and haemopericardium. Both cases underwentprompt graft placement thanks to rapid TEE diagno-sis. In the series by Mohr-Kahaly et al.[8] (8) theascending aorta was involved in three and the descend-ing aorta in 12 patients with intramural haematoma;two of the patients with ascending aorta involvementdied of aortic rupture at 1 and 3 days after presenta-tion. The authors concluded that prognosis in patientswith intramural haematoma is poor, reinforcing theimportance of rapid diagnosis and surgical treatmentin these cases. All cases with type A aortic dissection

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or intramural haematoma involving the ascendingaorta had an operation immediately after the diag-nosis; this approach allowed us to reduce the delayfrom admission to the hospital to arrival in operatingtheatre (120�60 min). Interestingly, the hospital mor-tality was 13% in our study, a percentage similar tothat observed by Rizzo et al.[6] who demonstrated thesuperiority of a rapid non-invasive diagnosis in com-parison with the traditional invasive (angiographic)approach (9% vs 40%). Banning et al.[23] performed aretrospective evaluation on TEE as the sole diagnosticinvestigation in patients with suspected aortic dissec-tion; in their series only one out of 22 cases with aorticdissection required a further diagnostic investigation;operative mortality in the 10 patients with type Aaortic dissection was 10%. In our prospective study,patients were managed according to the policy of ourinstitute, which is to treat cases with type A aorticdissection surgically; in these cases, TEE provided allanatomical and functional information that the sur-geon should know before surgery. Our data, therefore,confirm that TEE rapidly and safely gives all thenecessary diagnostic information and that furtherinvestigations before surgery are unnecessary[3–6,21,24].

Figure 4. Type A aortic dissection involving the right coronary artery (RCA). Left panel: in the long axisview of the ascending aorta (120 degrees) the extension of the flap towards the coronary ostia is not welldefined. Right panel: the short axis at 50 degrees clearly shows the dissection flap extension into the rightcoronary artery. LA, left atrium; TL, true lumen; FL, false lumen.

Thoracic Aortic Dissection and Intramural Haematoma 79

Limitations of the Study

Sequential introduction of multiplane and biplane probein the same patient has not been carried out because ofpractical and ethical aspects. Thus, the advantages ofmultiplane versus biplane TEE have been indirectlyassumed by the demonstration of the usefulness of viewsobtained in planes other than 0�–20� or 70�–110�, asproposed by Tardif et al.[7] and validated in a large seriesof intraoperative TEE by our group[17]. However, it ispossible that some intermediary planes may also beobtained with biplane probe through manipulation andsidewards flexions; these observations do not detractfrom our analysis, since multiplane TEE reduces thenecessity of manipulation of the probe thanks to elec-tronic rotation of the transducer: this is particularlyuseful in critically ill patients.

Conclusions

Multiplane TEE and biplane TEE have excellent andsimilar accuracies in the evaluation of aortic dissectionand intramural aortic haematoma; multiplane TEEfacilitates the correct alignment with the true short andlong axes of the ascending aorta through the assessmentof oblique views, thus improving the visualization ofcoronary arteries, entry tears, and aortic arch. Multi-plane TEE appears to be an ideal method as thesole diagnostic approach before surgery in type Aaortic dissection and in intramural aortic haematomainvolving the ascending aorta.

References

[1] Erbel R, Daniel W, Visser C et al. and the European Coop-erative Study Group for Echocardiography. Echocardiogra-phy in diagnosis of aortic dissection. Lancet 1989; 1: 457–461.

[2] Nienaber CA, von Kodolitsch Y, Nicolas V et al. Thediagnosis of thoracic aortic dissection by noninvasive imagingprocedures. N Engl J Med 1993; 328: 1–9.

[3] Ballal RS, Nanda VC, Gatewood R et al. Usefulness oftransesophageal echocardiography in assessment of aorticdissection. Circulation 1991; 84: 1903–1914.

[4] Erbel R, Oelert H, Meyer J et al. for the European Coopera-tive Study Group on Echocardiography. Effect of medical andsurgical therapy on aortic dissection evaluated by trans-esophageal echocardiography. Circulation 1993; 87: 1607–1615.

[5] Keren A, Kim CB, Hu BS et al. Accuracy of biplane andmultiplane transesophageal echocardiography in diagnosisof typical acute aortic dissection and intramural hematoma.J Am Coll Cardiol 1996; 28: 627–636.

[6] Rizzo RJ, Aranki SF, Aklog L et al. Rapid noninvasivediagnosis and surgical repair of acute ascending aortic dissec-tion. J Thoracic Cardiovac Surg 1994; 108: 567–575.

[7] Tardif JC, Schwartz SL, Vannan MA et al. Clinical usefulnessof multiplane transesophageal echocardiography: comparisonto biplanar imaging. Am Heart J 1994; 128: 156–166.

[8] Mohr-Kahaly S, Erbel R, Kearney P et al. Aortic intramuralhemorrage visualized by transesophageal echocardiography:findings and prognostic implications. J Am Coll Cardiol 1994;23: 658–664.

[9] Nienaber CA, von Kodolitsch Y, Petersen B et al. Intramuralhemorrage of the thoracic aorta. Circulation 1995; 92: 1465–1472.

[10] Nienaber CA, Spielmann RP, von Kodolitsch Y et al. Diag-nosis of thoracic aortic dissection. Circulation 1992; 85: 434–447.

[11] Cigarroa JE, Isselbacher EM, De Sanctis RW et al. Diagnosticimaging in the evaluation of suspected aortic dissection.N Engl J Med 1993; 328: 35–43.

[12] Evangelista A, Garcia-de-Castillo H, Gonzalez-Alujas T et al.Diagnosis of ascending aortic dissection by transesophagealechocardiography: utility of M-Mode in recognizing artifacts.J Am Coll Cardiol 1996; 27: 102–107.

[13] Flachskampf FA, Hoffmann R, Verlande M et al. Initialexperience with a multiplane transesophageal echotransducer:assessment of diagnostic potential. Eur Heart J 1992; 13:1201–106.

[14] Daniel W, Pearlman A, Hausmann D et al. Initial experienceand potential applications of multiplane transesophagealechocardiography. Am J Cardiol 1993; 71: 358–361.

[15] Roelandt J, Thomson I, Vletter W, Brommersma P, Bom N,Linker D. Multiplane transesophageal echocardiography: lat-est evolution in an imaging revolution. J Am Soc Echocardiogr1992; 5: 361–367.

[16] Hoffmann R, Flachskampf FA, Hanrath P. Planimetry oforifice area in aortic stenosis using multiplane transesophagealechocardiography. J Am Coll Cardiol 1993; 22: 529–534.

[17] Pepi M, Barbier P, Doria E et al. Intraoperative multiplane vsbiplane transesophageal echocardiography for the assessmentof cardiac surgery. Chest 1996; 109: 305–311.

[18] Tardif JC, Vannan MA, Taylor K et al. Delineation ofextended lenghts of coronary arteries by multiplane trans-esophageal echocardiography. J Am Coll Cardiol 1994; 24:909–919.

[19] Flaschkampf FA, Banbury M, Smedira N, Thomas J, GarciaM. Transesophageal echocardiography diagnosis of intra-mural hematoma of the ascending aorta: a word of caution.J Am Soc Echocardiogr 1999; 12: 866–870.

[20] Ionescu AA, Vinereanu D, Wood A, Fraser AG. Periaortic fatpad mimicking an intramural hematoma of the thoracic aorta:lessons for transesophageal echocardiography. J Am SocEchocardiogr 1998; 11: 487–490.

[21] Robbins RC, McManus RP, Mitchell RS et al. Managementof patients with intramural hematoma of the thoracic aorta.Circulation 1993, 88 (pt 2): 1–10.

[22] Braverman AC, Harris KM. Management of aortic intra-mural hematoma. Current Op Cardiol 1995; 10: 501–504.

[23] Banning AP, Masani ND, Ikram S et al. Transesophagealechocardiography as the sole diagnostic investigation inpatients with suspected thoracic aortic dissection. Br Heart J1994; 72: 461–465.

[24] Simon PS, Owen AN, Havel M et al. Transesophagealechocardiography in the emergency surgical management ofpatients with aortic dissection. J Thorac Cardiovasc Surg 1992;103: 1113–1138.

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