Transesophageal Echocardiography in Clinical Practice


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Currently almost all echocardiography labs undertake TEE and the vast majority of valve operations are performed with TEE guidance. Those in cardiac imaging know that the spatial and temporal resolution of the modality is unsurpassed and that it is relatively easy to get good images with minimal training. The purpose of this book is thus to give practical guidance to those undertaking training in the art of TEE. It is not an exhaustive text to be used for reference but one that should be used in conjunction with hands-on experience.

If used correctly it will help in realizing the true potential of TEE. Over the last 30 years the technological advances in transesophageal echocardiography TEE have been exponential and have been reflected by its increasing utilization. Currently almost all echocardiography labs will undertake the modality and the vast majority of valve operations are performed with TEE guidance.

The spatial and temporal resolution of TEE is unsurpassed and it is relatively easy to get good images with minimal training. Transesophageal Echocardiography in Clinical Practice provides pragmatic guidance to those undertaking training in TEE. It is not an exhaustive text to be used for reference but one that should be used in conjunction with hands-on experience and, if used correctly, this combination will help the reader understand the true potential of TEE.

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Condition: New. Excellent Quality, Service and customer satisfaction guaranteed! Book Description Springer. Seller Inventory Book Description Condition: New. US edition. Perfect condition. The room should be 20 m2 or larger and well ventilated. There must be a constant and reliable oxygen supply, suction facilities, and full resuscitation equipment near by ideally in the room. The operator should be experienced in TEE and appropriately accredited.

The technician needs to have a good knowledge of echocardiography to ensure image optimization. All personnel must be trained in basic life support and at least one member of the team must be competent at advanced life support. Introduction 1. For a morning list, I would normally advise nil by mouth NBM from midnight. For an afternoon list, patients can have a light breakfast before 8 a. Patients are advised to take their normal medication unless stated otherwise with a sip of water not less than 2 h before the procedure. For nonelective TEE studies, risks and benefits need to be weighed up in individuals who have eaten less than 4 h previously.

Intravenous metoclopramide to aid gastric emptying may be helpful, and in exceptional situations, intubation with rapid sequence induction can be necessary. In our institute, the patient is given an information booklet sent with their appointment date and logistical information if the procedure is elective to read Appendix 3 ; this is an adaptation of the advice given by the American Society of Echocardiography www.

Immediately prior to undergoing TEE, the patient is given a further information sheet Appendix 4 and a procedure specific consent form Appendix 5 ; the operator then explains about the procedure, answers any queries, and invites the patient to sign the consent form. This has the same cautions and contraindications to use as do other benzodiazepines, but compared with diazepam the most frequently used alternative , the recovery after use is faster and the amnesia is more profound. Once the patient is in the left lateral recovery position, all pre-study observations have been completed and we are ready to start the TOE 1—2 mg of midazolam is given.

Introduction over sedate. Do not give large boluses as this can lead to excessive sedation with associated risk of sedation-related complications. If sedation is used, the patient should be looked after by an adult for a minimum of 12 h and most institutes advise against driving, using dangerous machinery including kettles, irons, and cookers , lighting fires, making life changing decisions, purchasing expensive goods, signing cheques for large amounts of money, or signing legal documents for 24 h.

Other important influences include respiratory function, hemodynamic stability, and the likelihood that a patient will require repeat studies. Previously, I have used sedation alone but my practice has evolved, and now, in general, I give oropharyngeal local anesthetic spray as outlined above, and then, as a result, use smaller amounts of sedation. As a transesophageal echocardiographer, keep an open mind and become experienced with both methods on their own or in combination and then develop the methods that best suit you, your echo lab, and your patients.

Preparation and patient compliance are both essential for successful, nontraumatic intubation. The patient needs to be 1. Ideally they should lie in the left lateral recovery position with their neck in the midline and slightly flexed.

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I will give the oropharyngeal local anesthetic prior to them lying down, but before giving any sedation, I talk through the process of intubation and what I expect of them. Then the mouth guard is positioned and a small amount of sedation given. It is important to get the order right as some patients will become very sleepy and refuse to open their mouth even after 1—2 mg of midazolam leaving you to wait or requiring reversal of the sedation before you have even started! With the mouth guard in position, give a little suction to ensure minimal oral secretions prior to introducing the probe.

Note: The lock should be left off. The probe is then put through the mouth guard which is held firmly in place by the assistant as biting the probe will damage it and that can be very expensive and advanced gently but firmly along the central line of the tongue toward the posterior wall of the oropharynx.

Simultaneous with probe advancement, tell the patient that the probe is coming to the back of the tongue and ask them to swallow. Once the probe reaches the posterior oropharynx, a gag reflex will be invoked and the patient will retch, and this is the time to continue to advance the probe with or without flexion as the gag reflex and retching closes the epiglottis across the trachea and will allow safe intubation of the esophagus.

Intraoperative monitoring with transesophageal echocardiography in cardiac surgery

With the probe in the esophagus, further sedation can be given and the imaging begins. Introduction of the esophagus and stomach to other thoracic structures. It is also important to know the agreed terminology for each of the basic views so that we can effectively communicate. From the level of T1 to T4, the esophagus has lung on the left and right side, the trachea anteriorly and vertebrae posteriorly, and so no image is obtained. At the level of T4 Fig. The superior vena cava is anterior and to the right at this level but cannot be visualized due to the interposition of the trachea.

Between T4 and T8 Fig. The left pulmonary artery is also anterior to the esophagus at this level, but is obscured by the left main bronchus. From about the level of T8 to the level of T12 Figure 1. Thoracic CT slice taken at the level of T4 showing the relationship of the esophagus to the trachea and aortic arch. Posterior to the esophagus from T4 to T12 is the descending aorta; this is usually imaged at the end of the study by complete rotation clockwise or anticlockwise and subsequent slow withdrawal of the probe.

Below the diaphragm the stomach is directly inferior to the ventricles and these can be visualized by flexing the probe tip to bring it into apposition with the lesser curvature of the stomach transgastric window. Introduction Figure 1. Thoracic CT slice taken at the level of T10 showing the relationship of the esophagus to the left atrium and descending aorta.

When considering the assessment of specific cardiac structures, it should always be remembered that there can be marked interindividual variability such that any text can only be a guide. With each study undertaken adjustments to probe depth, degree of rotation and flexion and image plane angle will be needed to optimize the image dependent on what is seen. There are three main echocardiographic windows used during the standard TEE examination. These are the upper esophageal, mid esophageal, and transgastric and are approximately 20—30, 30—40, and 40—50 cm from the incisors respectively.

Once at the appropriate level, the probe can be manipulated in order to obtain the required image. In addition, the imaging plane can be rotated using the button on the underside of the probe handle, and the tip of the 1. TOE probe handle with button for imaging plane rotation, cogs for probe tip flexion, and lock for fixing probe tip in position.

The imaging plane angle can be rotated between When optimizing the image, whatever you do, do it slowly; then, if the image looks worse do the opposite. Flexion of the probe refines the view obtained. To anteflex the tip Fig. To lateral flex the tip Fig. Anteflexed probe tip. Therefore, with a constant velocity, the frequency and wavelength are inversely proportional.

Retroflexed probe tip. Attenuation is measured in decibels dB and is dependent on the medium through which the ultrasound travels and the frequency it is transmitted at Table 1. Laterally flexed probe tip. Table 1. Lateral resolution the ability to distinguish two points side by side is dependent on beam width, which must be less than the distance between the two points in order for them to be recognized as separate.

The beam width is smallest and lateral resolution best within the near field Fresnel zone ; the near field is longer at higher frequencies. Wavelength is smallest and axial resolution best at higher frequencies. Lateral resolution is always worse than axial resolution, and consequently, measurements are best taken axially rather than laterally. The frame rate is the time required to generate one frame. Each frame is made up of multiple scan lines so the major determinants of frame rate are the scan line density and the pulse repetition frequency PRF.

Frame rates increase with increasing scan line density which is achieved by reducing the sector width. Frame rates also increase at higher pulse repetition frequencies. PRF is proportional to the velocity of ultrasound in that medium this effectively is a constant and inversely proportional to the distance traveled by the ultrasound dependent on sector depth and tissue penetration. The PRF can, therefore, be increased with consequent increase in frame rate and temporal resolution directly by decreasing the sector width or indirectly by increasing the transmission frequency and thus decreasing the depth of penetration.

It is, therefore, possible to get clear images of the heart with almost no effort excepting the need to intubate the patient , and it is perhaps this near instant gratification that leads interventional cardiologists to positively push their way into the echo lab to do a TEE when it would normally take a threat of violence to get them into the echo lab to do a transthoracic echocardiogram.


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There are, however, cases when image quality is not immediately perfect, and for such instances, it is worth knowing how to improve the quality of your study. For those who perform transthoracic echocardiograms, you will probably be familiar with the following as the principles are exactly the same. Frequency: High frequency transmission is good for the near field but leads to marked loss of resolution in the far field and decreases the depth of tissue penetration due to attenuation.

These factors can result in suboptimal imaging of the ventricles especially the left ventricular apex from the mid esophageal window. The frequency can be reduced to improve imaging of the ventricles from the mid esophageal window. Image sector depth: This should be adjusted so that the bottom of the sector is approximately 1 cm distal to the area of interest e.

Image sector width: This should be adjusted so that the sector is approximately 1 cm wider than the area of interest e. Focus: Lateral resolution is increased by focusing the beam but this limits the near field depth and increases beam divergence distal to the focal point with proportionally greater loss of lateral resolution in the far field. The focus point can be 1. Overall gain: It is important to have sufficient gain but remember that excessive gain will reduce lateral resolution.

Time gain compensation TGC : The further an object from the transducer, the greater the attenuation of its reflected signal. To compensate for this variation in signal strength, the echo machine has a slide potentiometer that allows the operator to amplify more distant signals relative to near signals. Compress: This function redistributes the entire grey scale range to those echoes that are above the compress level.

Decreasing the compress level can be done manually and produces a more black and white image. Normally, I do not adjust the compress from its standard setting; the exception is that I find decreasing the compress especially helpful when looking for left atrial appendage thrombus.

Figure 1. Time Gain Compensation slide potentiometer aligned in a curve recommended starting position. It is my normal approach to use write zoom in all TOE studies to optimize visualization of any area of interest. It should be remembered that the degree of magnification and improved resolution is inversely proportional to the size of the zoomed area. Complete TOE Studies A transesophageal echo study should be planned; this seems an obvious statement but is all too often forgotten. Before starting, you need to know what question is to be answered and what information is already available.

The TOE is almost always performed after a transthoracic echo study and this should, where possible, be reviewed by the operator prior to commencing the TOE. The first part of the TOE study should then be targeted to specifically answer the question e. Once again it seems unnecessary to make such a statement, yet history is littered with accounts of intolerant patients removing the probe prior to completion of the study leaving a red faced operator with beautiful, but superfluous pictures and the question unanswered.

To add insult to injury in such cases the aforementioned patient is often unwilling to have the TOE repeated! Once the question posed is answered there are two main options.


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The first option is to conclude the study at that point; this option is favored by some and certainly increases the throughput of your TOE lab. The second option is to continue and perform a complete study; this is my preferred option providing the patient is tolerating the procedure and there is no hemodynamic instability. The reasons I perform a complete rather than targeted study are: 1.

Targeted vs. To perform a complete study, it important that an operator has their own routine and checklist to ensure nothing is missed. Whatever routine is followed it should be based on the recommendations of the American Society of Echocardiography5 and the European Society of Echocardiography. Douglas P et al. Ward RP et al. Seward JB et al.

Khandheria BK et al. Am J Cardiol. Shanewise JS et al. Flachskampf FA et al. Eur J Echocardiography. In other studies, it is secondary, but a very important objective. Whether a primary or secondary objective, it is necessary to have a systematic approach to ensure the appropriate images are obtained. For those familiar with transthoracic echocardiography TTE , the mid esophageal views are analogous to the transthoracic apical views; the transgastric short axis and long axis views are analogous to the transthoracic parasternal short axis and long axis views.

The transgastric 2 chambers view looks at the same walls as the TTE apical 2 chambers view, but is interrogating radial as opposed to longitudinal contractility. The approximate image plane angles used for each view are outlined above. The Left Ventricle Figure 2. Mid esophageal 4 chambers ME 4Ch view. Figure 2. Mid esophageal 2 chambers ME 2Ch view. Transgastric 2 chambers TG 2Ch view. Reference limits for chamber size, mass, and systolic function are quoted in Table 2.

The Left Ventricle should be averaged over 3—5 consecutive beats of good quality in patients in sinus rhythm 10 beats if in atrial fibrillation [AF]. Having intubated the patient, advance the probe to the mid esophageal level to obtain the 4 chambers view; from here it is possible to get an immediate impression of the left ventricular structure and function. To adequately visualize the endocardial borders of all the segments in this, and the other mid esophageal views, it is often necessary to adjust the settings to optimize your image; the focus point should be moved toward the apex, the image sector width reduced, and on occasions, the imaging frequency reduced.

After 2D imaging, spectral and tissue Doppler imaging is undertaken to evaluate left ventricular diastolic function. Having completed the ME 4 chambers view data acquisition, move around the scan plane angles at the mid esophageal level imaging the ME 2 Ch then ME LAX views for further two-dimensional and Doppler assessment of the left ventricle. At this point almost all the necessary data on left ventricular structure and function has been obtained, and if the study is terminated early due to patient compliance , then at least the questions can be answered.

Then continue scanning in the esophagus looking at the right ventricle, atria, valves, etc. The linear dimensions are ideally measured in the transgastric 2 Ch view using two-dimensional imaging; the alternative is the ME 2 chambers view, but there is a greater potential for measurement error as accuracy in this window is dependant on lateral, as opposed to axial, resolution.

When measuring the linear dimensions using two-dimensional imaging, convention states that these measurements are taken from the endocardium of the anterior wall to the endocardium of the inferior wall in a line perpendicular to the long axis of the left ventricle at the junction of the basal and mid thirds of the long axis. End diastole can be defined at the onset of the QRS, but is preferably defined as the frame in the cardiac cycle after mitral valve closure or the frame in the cardiac cycle in which the cardiac dimension is the largest my preference.

End systole is best defined as the frame preceding mitral valve opening, or the time in the cardiac cycle in which the cardiac dimension is the smallest my preference.

The impact of transesophageal echocardiography on daily clinical practice.

The LVIDd and LVIDs can also be measured using M-mode in the transgastric 2 chambers view, but care is required to ensure the cursor is perpendicular to the long axis of the ventricle. Also, if using M-mode the reference limits are different because the dimensions are bigger than those measured using 2D. The Left Ventricle wall; this often being necessary to ensure adequate image quality , whereas even with the probe tip anteflexed, the mid esophageal 2 chambers view does not foreshorten the LV as it is perpendicularly orientated.

From a practical point of view, the LV cavity is planimetered i. If, however, an accurate measurement is required, the transgastric window mid short axis is recommended as the spatial resolution is improved as detailed above , and thus the potential for measurement errors reduced. The posterior inferolateral and septal wall thickness at end diastole PWTd and SWTd respectively should be measured and reported as normal 2.

The Left Ventricle heart disease when compared with the transthoracic method that averages the values calculated from the 4 and 2 chambers views. The Left Ventricle Fig. From my point of view the applicability of the LV stroke distance as a measure of systolic function in other clinical scenarios is uncertain and coupled with the technical difficulties of obtaining good traces means that I rarely use it as a measure of LV systolic function in my TEE studies.

Despite my reservations, I believe operators should be aware of it as there are times when it may be useful. Left ventricular outflow tract LVOT pulse wave Doppler recording from the transgastric long axis view. LVOT velocity time integral obtained by tracing around the pulse wave Doppler profile In the four chambers view, the anterolateral wall to the right of the screen and inferior septum in the middle of the screen are visualized; the basal, mid, and apical segment of each wall should be scored. The anterior wall to the right of the screen and the inferior wall to the left of the screen are seen in the ME 2 chamber view and the basal, mid, and apical segment of each wall should be scored.

Finally, in the mid esophageal long axis view, the anterior septum to the right of the screen and the inferolateral wall to the left of the screen are evaluated. According to the convention of the 16 segment model, only the basal and mid segments of the walls in the LAX view are scored as the apical segments have already been represented in the 4 chambers view. The caveat to this is that the imaging of the septal and lateral apical segments can be better in the LAX view as opposed to the 4 chambers view and in this case the LAX view should be used to score.

All the basal and mid and occasionally the apical segments can also be imaged in the transgastric views where radial contractility is seen. Although not essential, if the mid esophageal images are good, it is still worth scoring the segments in these views as a cross reference. The Left Ventricle worse the prognosis although there is not a single figure that differentiates bad from good a value of greater than 1. In nonsurgical scenarios, this can be used to differentiate single from multivessel coronary artery disease.

Specifically in perioperative cardiac cases, it can identify which arterial territory is hypoperfused; invaluable information especially if there is any difficulty coming off bypass. As can be seen, the transgastric mid short axis view has all coronary artery territories represented simultaneously and is, therefore, a good view for monitoring for ischemia. The caveats Figure 2. Correlation of the myocardial segments with likely coronary artery supply. When evaluating diastolic function, there are many parameters that can be used; no one is sufficiently robust to be used in isolation and so algorithms of combinations of parameters have been developed.

There is no absolute right or wrong method of assessment and each operator needs to consider for themselves how they wish to tackle the question of diastolic function remembering that most studies on the subject have utilized transthoracic echocardiography. Also included in the algorithm are the left ventricular mass, left atrial size, and tricuspid regurgitant jet velocity and derived pulmonary arterial systolic pressure [PASP] ; the measurement of these parameters is discussed in their relevant sections.

The transmitral flow is first recorded using continuous wave Doppler to ensure the maximal velocities are obtained. The color Doppler is applied to align the Doppler cursor with blood flow and then the image of the valve is zoomed thus increasing resolution prior to sample volume positioning.

Pulse wave Doppler recording of the mitral inflow taken from the mid esophageal long axis view demonstrating the measurement of the peak E wave velocity, peak A wave velocity and the E wave deceleration time. Image quality can be enhanced by zooming on the annulus before applying the PW Doppler, and by adjusting the sample volume size to encompass the entire annular diastolic excursion usually 5—10 mm.

The duration of atrial systolic reversed flow into the pulmonary veins Ar is measured from the pulse wave Doppler recording obtained by placing the sample volume 2—3 mm greater than 0. All measurements should be averaged over a minimum of three beats. When comparing measurements taken from different sites e. Step one in the assessment of diastolic function is the assessment of systolic function.

Pulsed wave Doppler of pulmonary vein flow demonstrating systolic S and early diastolic D forward flow followed by reversed flow during atrial systole Ar. The severity of diastolic dysfunction is correlated with the left ventricular end diastolic pressure EDP that, in turn, reflects the mean left atrial pressure LAP. This can then be refined into grade I normal left atrial pressure; mild diastolic dysfunction and grade IA elevated left atrial pressure; mild-moderate diastolic dysfunction based on an estimation of the LAP as outlined below.

Severe diastolic dysfunction can be subdivided into reversible IIIa and irreversible IIIb with consequent implications on prognosis. True differentiation between grades IIIa and IIIb requires repeat evaluation of Doppler parameters after a period of appropriate treatment e.

TRANSESOPHAGEAL ECHOCARDIOGRAPHY

The Left Ventricle assumption is not valid in the presence of sinus tachycardia or first degree AV block; in such instances atrial contraction often occurs before early diastolic mitral and pulmonary venous flow velocities have declined to zero thus increasing the width of the mitral A wave and decreasing the apparent duration of atrial systolic flow reversal in the pulmonary veins.

Categorization of an increased left ventricular mass and identification of concentric remodeling based on the relative wall thickness and mass of the left ventricle. Indices used in the assessment of diastolic function with associated scores dependant on normality or degree of abnormality.

Lang RM et al. Metcalf MJ et al. Lancet ; i: —3. Paulus WJ et al. Eur Heart J. Nagueh SF et al. The Left Ventricle A systematic approach to left ventricular assessment. The smooth walled portion is larger and originates embryologically from the pulmonary veins that combine to form a common pulmonary vein before becoming integrated with the inferior portion of the left atrium. The trabeculated portion of the adult LA is confined to the appendage LAA and is all that remains is of the primitive left atrium. There are therefore no specific left atrial views.

Ideally, therefore, any echocardiographic assessment should include LA volume as part of the parameters measured. The two recommended methods of measuring volume are the ellipsoid and the M. The reasons for this are firstly that due to near field drop out, the posterior wall of the LA is not directly visualized, so it is not possible to accurately measure the long axis; an integral measurement in the ellipsoid model.

For the same reasons it is not possible to accurately measure the left atrial area, and therefore, the only objective measure of left atrial size that is feasible during TOE examinations is the transverse diameter. The operator should therefore, try to acquire a good ME 4 chambers view with clear visualization of the left atrial septal and lateral walls, and measure the maximal systolic dimension at the mid atrial level Fig. In a population study of normal subjects the mid LA dimension was 3. Values greater than 4. Measuring of the maximal systolic dimension of the left atrium from the mid esophageal 4 chambers view.

One hypothesis is that the LAA acts as a capacitance chamber allowing sudden changes in LA volume to be accommodated without marked increases in left atrial pressure LAP. From a practical perspective, however, the LAA acts as a culde-sac with a high incidence of thrombus especially in the presence of atrial fibrillation AF.

It is shaped like an old fashioned money purse with a thin neck and somewhat bulbous body. The orifice of the neck of the appendage curves around the lateral aspect of the LA between the left upper pulmonary vein LUPV posteriorly and the junction of the LA and pulmonary trunk anteriorly. Both its shape and position relative to the esophagus demonstrate marked inter-individual variability, and so a complete assessment of the LAA is one of the more challenging tasks in a TEE study.

For LAA imaging, I usually start at the mid esophageal 4 chambers view and then withdraw the probe slightly not quite as far as the upper esophageal window. The probe is then maximally ante-flexed and the image plane angle rotated until the appendage is seen. In order to obtain the clearest image and properly assess one of the most topographically complex cardiac structures in each plane it is often necessary to adjust the probe depth and manually rotate the probe clockwise or anti-clockwise.

Further 2D image optimization is achieved by reducing the image sector depth and width or zoom function used to improve spatial and temporal resolution. The Left Atrium Figure 3. Figure 3. Pulse wave Doppler of left atrial appendage blood flow demonstrating emptying A and filling V velocities. The Left Atrium reasonable flow in all areas Fig. Finally the global contractile function of the LAA is evaluated using pulse wave Doppler, and by measuring the peak emptying velocity Fig. Color Doppler is added to the left side of the screen and the probe is advanced slowly until 2 distinct pulmonary inflows are seen Fig.

Mid esophageal 4 chambers view with the probe rotated so that the inter-atrial septum is horizontal and in the centre of the screen. Color Doppler demonstrating two distinct right pulmonary vein inflows red. Starting from the ME 4 chambers view the probe is withdrawn slightly, and the color Doppler is added on the right side of the screen. Left upper and lower pulmonary vein inflow red coded blood flow.

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In this view the flow to the right of the screen is from the upper and the flow to the left of the screen is from the lower pulmonary vein. Pulsed wave Doppler of pulmonary vein flow demonstrating systolic flow reversal S followed by very dominant early diastolic forward flow D. This suggests severe mitral regurgitation.

Normal flow consists of forward systolic S and early diastolic D flow followed by reversed flow during atrial systole Ar. When describing pulmonary vein flow patterns it should be documented whether systolic forward flow is dominant or recessive when compared to diastolic forward flow or if it is reversed Fig. The duration of A wave reversal can also be measured as part of a diastolic function assessment as detailed in Chap. References 1. Transesophageal echocardiography and the mitral valve that sits only 5—10 cm from the transducer with nothing but blood between them were made for each other with the spatial and temporal resolution of the technique allowing the valve with its complex structure and motion to be perfectly described.

Assessment of the mitral valve MV is, therefore, one of the commonest indications for TEE and should be undertaken in all patients being evaluated for preoperatively or undergoing perioperatively MV surgery. The posterior leaflet has clefts that divide it into 3 scallops P1, P2, and P3 ; the anterior leaflet has no such scallops, but is described as having three regions that reflect those of the posterior leaflet A1, A2, and A3 respectively. The nonleaflet apparatus consists of the saddle-shaped mitral annulus, the chordae tendinae primary chordae attached to the free edges of the leaflets, secondary and tertiary chordae attached to body of leaflets , and papillary M.

The Mitral Valve muscles anterior: chordae attached to lateral aspects of leaflets; posterior: chordae attached to medial aspects of leaflets. The function of the valve is complex and is dependent on each component as well as the left ventricle especially the basal segments and left atrium. A complete assessment of the valve should, therefore, include an interrogation of these chambers.

Evaluation usually starts with the mid esophageal views and concludes with the transgastric views. Start by obtaining the mid esophageal ME 4 chambers 4Ch view with the image sector width and depth adjusted in order to include both ventricles including the cardiac apex and both AV valves; use 2D then add color Doppler to the valves. This allows a quick overview of atrial size, ventricular size and function as well as an initial impression of the valvular structure and function.

The image sector depth is then decreased to a level that just allows inclusion of the mitral leaflets and the chordae, and further optimization of the image may be gained by using the zoom mode. With all imaging plane rotations described, it is necessary to simultaneously manually rotate the probe [gently] anticlockwise to maintain the appropriate cut through the left ventricle and mitral valve. The depth does not need to be adjusted as described, but I prefer to do this as orientation is easier and it allows concurrent assessment of left ventricular regional and global systolic function avoiding repetition.

In each view, the valve should be kept central while the probe depth is changed and flexion anterior, posterior, and lateral is applied in order to fully evaluate each leaflet and the commissures completely 2D alone then with 4. Diagrammatic representation of the relationship between each mid esophageal view and the parts of the mitral valve leaflets seen. The relationship between each mid esophageal view and the parts of the leaflets seen is diagrammatically represented in Fig. When describing which scallops are seen in each view, the list starts with scallop furthest to the right of the screen.

To remember which leaflet is which an aide memoir is that the anterior leaflet is always next to the aortic valve. Figure 4. Mid esophageal 4 chambers view at zero degrees with P2 and A2 visualized. This view usually allows excellent imaging of the chordae and the papillary muscles and helps in the understanding of what attaches to where. The Mitral Valve Figure 4. Mid esophageal commissural view with P1, A2, P3, and both commissures visualized. Mid esophageal 2 chambers view with A1, A2, and P3 visualized. Mid esophageal long axis view with A2 and P2 visualized.

By convention it is measured at end systole the beat just prior to MV opening in the 4 and 2 chambers views from the insertion point of the posterior leaflet to the insertion point of the anterior leaflet. The upper limit of normal for the annular diameter is 3. Having completed the mid esophageal views, the study of the MV is concluded with the transgastric views. Transgastric the basal short axis view valve closed with all 6 scallops and both commissures anterolateral [ALC] and posteromedial [PMC] visualized.

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Although it is often a struggle to 4.

Transesophageal Echocardiography in Clinical Practice Transesophageal Echocardiography in Clinical Practice
Transesophageal Echocardiography in Clinical Practice Transesophageal Echocardiography in Clinical Practice
Transesophageal Echocardiography in Clinical Practice Transesophageal Echocardiography in Clinical Practice
Transesophageal Echocardiography in Clinical Practice Transesophageal Echocardiography in Clinical Practice
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