Mitral Regurgitation Quantification Review

Upon successful completion of this course, you will be able to: Recognize the need for comprehensive evaluations, Distinguish between qualitative and quantitative methods for evaluating mitral regurgitation, Explain optimization techniques for data acquisition,   Classify regurgitation severity based on guidelines.   Select ► to continue Identify limitations of various evaluation methods, Due to varying regulatory requirements, product availability varies from country to country. Some/all of the products and/or features referred to in this module may or may not be available in your country. This course addresses an international audience of healthcare customers and cannot consider all country-specific statistics, guidelines, and regulations. It is your responsibility to understand the regulations for your country or regions.   Images and graphics used in this tutorial are for educational purposes only. They may have been modified or compressed and may not reflect the actual image quality of the system. Selecting the ► continues this course and confirms that you have read and understood this disclaimer. Welcome to the “Mitral Regurgitation Quantification Review”. This tutorial covers the key components to a comprehensive echocardiographic evaluation of mitral regurgitation, or MR. Regurgitation is the backwards flow of blood during systole (into the left atrium for MR) from either cardiac remodeling or valvular structural abnormalities. The latter is known as primary or degenerative mitral valve regurgitation and is the leading cause of valve disease in the USA and second leading in Europe.1 The goal of the echocardiographic exam is to identify the mechanism, duration and severity of regurgitation. The answer often requires both qualitative and quantitative approaches.   Select ► to continue Congratulations! You have completed the Mitral Regurgitation Quantification Review. Listed below are the key points presented in this tutorial. Take time to download and review the document below before you proceed to the final quiz. When you have finished reviewing, click the next arrow to continue.   Download and print a copy of the Course Review.   Recognize the need for comprehensive evaluations Distinguish between qualitative and quantitative methods for evaluating mitral regurgitation Explain optimization techniques for optimal data acquisition Identify limitations of various evaluation methods Classify regurgitation severity based on guidelines    ACUSON SC2000, RES, eSie PISA and eSie Flow are trademarks of Siemens Medical Solutions, USA, Inc.   Select ◄ to go back                                                                                                                                       Select ► to continue   Now that we have discussed the various quantitative and qualitative methods of evaluating mitral regurgitation, we need parameters to classify them into the various grades of MR.   Both the American Society of Echo and the European Association of Echocardiography have guidelines that outline the classification parameters for mild, moderate and severe mitral regurgitation.   Click on the icon below to learn more about MR severity classification. Select ◄ to go back                                                                                                                                        Select ► to continue   Standards Learn more about MR severity classification Tab TitleTextStructural Parameters Evaluation Parameter MR Severity* MILD MODERATE SEVERE Mitral Valve Anatomy No or mild structural abnormality Normal to Moderate abnormality or leaflet tenting  Severe valve lesions including but not limited to flail, ruptured papillary muscle, large perforation Chamber size Normal Normal to mild dilatation Dilated (cases of acute MR may have normal chamber size) *Information based on data from Zoghbi et al 2017 and Lancelotti 2013 Qualitative Parameters Evaluation Parameter MR Severity* MILD MODERATE SEVERE Color flow jet area Small, central, narrow Variable Large central jet or eccentric variable size jet Signal Intensity Faint, partial, parabolic Dense but partial or parabolic Holosystolic, dense, triangular Pulmonary Vein Flow Systolic dominance Normal or systolic blunting Minimal to no systolic flow, systolic flow reversal (except in cases of atrial fibrillation or elevated left atrial pressure) Mitral Inflow A-wave dominant Variable E-wave dominant (>1.2 m/s) *Information based on data from Zoghbi et al 2017 and Lancelotti 2013 Quantitative Parameters Evaluation Parameter MR Severity* MILD MODERATE SEVERE Vena Contracta <0.3 cm Intermediate ≥0.7cm (0.8 for biplane) EROA (2D PISA) <0.2 cm2 0.20-0.29 cm2 0.3-0.39 cm2 ≥0.40 cm2 (may be lower in secondary MR with elliptical ROA) Rvol (mL) <30 mL 30-44 mL 45-59 mL ≥60 mL (may be lower in low flow conditions) RF (%) <30% 30-39% 40-49% ≥50% *Information based on data from Zoghbi et al 2017 and Lancelotti 2013  Patient outcomes depend on diagnosis and subsequent treatment of the pathology. Treatment and potential intervention depend on diagnosis and management. Diagnosis begins with a complete and thorough mitral valve regurgitation evaluation, which is where we begin.   Zoghbi et al. identify parameters required for a full evaluation of mitral regurgitation using transthoracic echo. A comprehensive evaluation includes: patient clinical information, valve imaging, qualitative and quantitative evaluation, chamber size, structure, and function, pulmonary artery pressure estimation. Select ◄ to go back                                                                                                                                          Select ► to continue   1. Clinical Information: includes patient height, weight and body surface area (BSA) in addition to patient history, symptoms and clinical findings. This information sets the framework, as the echocardiographic data may have different implications depending on the patient’s circumstances and medical history. Interpretation of data should never rely on one single parameter but rather a combination of methods. This is especially important in the intermediate MR severity levels where transition from mild to moderate or from moderate to severe classification may indicate a different course of treatment or possible intervention.   2. Valve Imaging: The next step in a complete evaluation is imaging of the valve itself to classify structure and function.  Click on the icon below to learn more about mitral valve morphology.   3. Cardiac Remodeling: The echocardiogram must also include information on cardiac remodeling. Chamber size, structure and function are crucial to an accurate diagnosis. This is another parameter in identifying the mechanism of the regurgitation and if it is chronic or acute.  Moderate to severely dilated chambers generally identify the valve incompetency as chronic and help determine the regurgitation severity and duration. Conversely, in acute regurgitation, there is minimal to no chamber dilation even in severe classifications.  Signs of acute severe regurgitation instead include a large regurgitant orifice.3   4.  Pulmonary Pressures: In addition to left atrial chamber size, it is important to assess systolic pulmonary pressure (SPAP). It is possible that the excess blood flow into the left atrium causes an increase in pulmonary pressures.4 Use continuous wave, or CW Doppler through the tricuspid regurgitant jet and measure maximum velocity to estimate right ventricular pressure. Add in the estimated right atrial pressure based on established guidelines to obtain SPAP. Find more information on estimating pulmonary pressures at the web address listed below. http://www.asecho.org/wordpress/wp-content/uploads/2013/05/Echo-Assessment-of-Right-Heart-in-Adults.pdf.    Click on the icon below to learn more about identifying mitral valve morphology. Select ◄ to go back                                                                                                                                            Select ► to continue Valve Imaging Learn more about mitral valve morphology Tab TitleTextFunction A prolapsed valve leaflet or scallop may result from both degenerative and secondary processes. Designation of mitral valve prolapse (MVP) does not have general clinical agreement; however, Feigenbaum (2010) describes prolapse as “when one or both leaflets break the plane of the mitral annulus in a non-symmetric manner.” (p.327). The parasternal long-axis or the apical two-chamber generally provide the best visualization for this prolapsing motion.9      In contrast, flail describes the functionality of the leaflet or a portion of the leaflet. Flail may occur with or without prolapse and generally results from a ruptured chord. The leaflet or scallop no longer maintains its integrity and floats back into the atrium.9     The diagrams to the left depict bileaflet prolapse (Fig. A) single scallop prolapse (Fig. B) and flail posterior leaflet (Fig. C). The blue arrow denotes the resultant direction of regurgitation. Fig. A Fig. B Fig. C Shape Restriction and tenting describe the shape of the mitral valve leaflets from such processes as mitral stenosis or ischemic cardiomyopathy. As the leaflets become calcified in mitral stenosis, the individual motion because restricted. (Fig A)     Fig. A Ischemic cardiomyopathies dilate the ventricle, stretching the mitral annulus. The result is a tenting of the mitral leaflets as they struggle to coapt.11 (Fig B)  Fig. B Structure In addition to the coaptation shape, the leaflets themselves may become thickened and or calcified. Thickening of the leaflets may lead to later calcification as in rheumatic disease.   It is also important to delineate between leaflet calcification and annular calcification. Both processes can lead to stenosis and regurgitation, but the interventional implication may be different.   Calcified Thickened After completing preliminary assessment methods discussed in the previous sections, it is pertinent to utilize both qualitative and quantitative echocardiographic methods for comprehensive evaluation.                           Qualitative methods are subjective and have more inter-observer variability. In general, qualitative methods are still valuable for classifying regurgitation as mild or severe but intermediate levels require more quantitative methods. Several factors influence these qualitative methods including transducer frequency, color gain, and Nyquist limit settings.11   Qualitative methods for assessing severity of  MR include: Color flow jet area evaluation Signal intensity Amount of antegrade flow across the mitral valve Retrograde pulmonary venous flow pattern After detecting significant mitral regurgitation, serial echocardiograms with quantitative data are crucial for monitoring disease progression. This aids clinicians in medical management and timing interventions. Continue to the next section to learn about quantitative assessment methods.   Click on the icon below to learn more about qualitative assessment methods. Select ◄ to go back                                                                                                                                         Select ► to continue Qualitative Methods Learn more about qualitative assessment methods Tab TitleTextColor Flow Prior to the availability of quantitative methods for assessing mitral regurgitation, clinicians relied on more subjective methods such as the amount of area the regurgitant jet occupies in the left atrium to classify severity.  Current recommendations are to use color flow Doppler to detect mitral regurgitation but not to classify its severity.4 By angulating the transducer through the entire valve apparatus, color flow Doppler can identify the origin, number and direction of the regurgitant jet. If color flow is useful for detecting MR, why is color flow not useful in classifying MR severity?     Several factors limit the accuracy and usefulness of color flow imaging. Some of them are operator dependent while others have to do with the nature of the regurgitant mechanism. Two operator dependent settings include Nyquist limit and color gain. If the Nyquist limit on the color scale is set too low, there is an overabundance of aliased flow. Setting the Nyquist limit too high may miss real regurgitant flow. Zoghbi et al. (2017) recommend standard settings as “a Nyquist limit (aliasing velocity) of 50-70 cm/sec,” (p.308). Color gain settings must also be set appropriately. Setting the color gain too high may miss color flow; if it is too low it may overemphasize the amount of flow.3 Zoghbi et al. (2017) recommend using “a color gain that just eliminates random color speckle from non–moving regions.” (p.308). What is wrong with these two images?     Reduced or increased blood pressure also influences the color Doppler display. For flow to occur there needs to be a pressure difference between the two chambers. This difference is the Doppler shift which displays echoes as color.12 A patient with a low blood pressure will have a lower pressure gradient and the amount of color flow visualized will be less. Conversely, the patient with high blood pressure will have a high-pressure gradient and the amount of color will be over-emphasized.11 Signal Intensity While continuous wave (CW) Doppler is an important component of PISA (proximal isovolumetric surface area) evaluation (covered later in this tutorial), by itself it does not provide much useful information for mitral regurgitation. Normal MR jet velocities are somewhere between four and six meters per second, reflecting the systemic systolic pressure difference between the left atrium and left ventricle.11 Since these velocities are normal, they do not provide information on the severity of the regurgitation. This differs from tricuspid regurgitation (TR) evaluation in that pulmonary pressures are generally much lower than systemic pressures. A high velocity TR jet would indicate abnormally high pulmonary pressures.   How does the Doppler signal provide additional information for the clinician?   Despite its limitations, the intensity and shape of the Doppler signal provides some qualitative information for clinicians. A stronger signal denotes more regurgitation than a fainter signal. The shape, density and completeness of the signal also provide some information. A truncated waveform, with a triangular shape and early peak velocity, may be indicative of severe MR.11   An eccentric jet may underestimate the signal due to the inability to align the transducer parallel to flow. The waveform will not incorporate signals from multiple jets; also potentially underestimating the signal.11     This CW Doppler spectral display demonstrates a strong, complete regurgitant jet waveform. In comparison, this CW Doppler spectral display demonstrates an incomplete waveform. This could be the result of misalignment of the transducer, an eccentric jet or multiple jets.    Mitral Inflow Pulsed wave (PW) Doppler of the mitral inflow is a well-known method for evaluating left ventricular diastolic dysfunction. It is also used in the equation for calculating regurgitant fraction, which we cover later in this tutorial. Less commonly used, it can be a supporting parameter specific, but not sensitive, for severe mitral regurgitation. Sampling the mitral inflow with PW Doppler provides information on the amount of blood travelling from the left atrium to the left ventricle in diastole. Since severe MR results in more volume returning to the left atrium, diastolic flow to the left ventricle also increases. In these cases, the mitral inflow pattern is E-wave dominant, with velocities at 1.2 m/s or above. Therefore, in most cases a dominant A-wave in the mitral inflow pattern excludes severe regurgitation.11   This PW Doppler spectral display demonstrates A-wave dominance.       This is a PW Doppler spectral display from a patient with severe MR and demonstrates a high-velocity E-wave and low A-wave velocity.    Pulmonary Venous Flow The echocardiogram evaluation for mitral regurgitation includes sampling of the pulmonary veins with PW Doppler.     Why do I have to sample pulmonary venous flow? They are hard to find and I am in a hurry!     Normal pulmonary vein flow has antegrade systolic (s) and diastolic (d) flow. As mitral regurgitation increases, the flow pattern begins to change. Normal flow (Fig. A) begins to change to a more blunted waveform. In the presence of severe MR, the systolic flow will reverse and become retrograde. (Fig. B)      This change to a blunted flow pattern also occurs with increased left atrial pressures or atrial fibrillation       Eccentric MR jets may complicate pulmonary vein evaluation. It is possible to have reversed systolic flow in one pulmonary vein due from a moderate eccentric jet (Fig C) with normal or blunted flow in the unaffected veins. To confirm true systolic flow reversal versus an eccentric jet, Zoghbi et al. advise sampling all four veins, when  possible.11   Fig. A   Fig. B     Fig. C   The asymmetrical shape of the mitral valve (MV) makes evaluating mitral regurgitation a challenging process.  Echocardiography is currently the main resource for observance and analysis of mitral regurgitation severity.2 The American Society of Echo (ASE) and the European Society of Cardiology (ESC) recommend transthoracic echocardiography as the initial evaluation modality, proceeding to transesophageal echocardiography or cardiac magnetic resonance imaging if the transthoracic images are non-diagnostic or assessment requires further evaluation.3, 4 By the end of this tutorial you will understand the importance of an accurate, comprehensive evaluation and the steps required to achieve a complete diagnostic evaluation. Notice the asymmetry of the mitral valve in the top diagram compared to the relatively symmetrical shape of the aortic valve on the bottom.   Select ◄ to go back Select ► to continue         What type of quantitative data should an echocardiogram evaluation of MR provide?   There are a few well-known parameters that, when performed correctly, provide quantifiable and reproducible data. Quantitative methods include: Vena contracta size Volumetric Calculations PISA Flow Quantification Aside from the asymmetric geometry of the mitral valve, there are several limiting factors in traditional 2D mode echocardiographic evaluation of mitral regurgitation. These include operator programmed system settings as well as the hemodynamic effects of jet type (central versus wall-hugging) and number of jets (single versus multiple), heart rate and left atrial compliance.2 Click on the icon below to learn more about quantitative evaluation methods. Select ◄ to go back                                                                                                                                        Select ► to continue   Quantitative Methods Learn more about quantitative evaluation methods Tab TitleTextVena Contracta A relatively simple semi-quantitative method measures the vena contracta, or VC. This is a useful measurement for eccentric jets, but does not work well with multiple jets. It may also overestimate non-holosystolic jets. When imaging with color Doppler, measure the VC at the narrowest portion of the regurgitant jet (orange arrow), on the atrial side, just after passing through the mitral valve or regurgitant orifice. This is the convergence zone. Although this method requires the use of color Doppler, the pitfalls that apply to color Doppler imaging do not have quite the same effect on VC measurements as they do on visualization of the regurgitant jet itself.3    Both 4D and 2D imaging produce a VC measurement. For 2D imaging, it is important to align the transducer beam as parallel to flow as possible. This may require manipulating the transducer angulation outside of standard imaging planes to get the best possible image.3 Since this is a precise measurement and any discrepancy can cause significant changes in classification, optimize the image so the convergence zone is well visualized before measuring. To obtain high lateral and temporal resolution, make sure to narrow the color sector. If available, it is also helpful to use RES™ enhanced resolution imaging format to enlarge the region of interest while not sacrificing resolution. After optimizing the image, measure the width of the vena contracta. The larger the width, the more severe the regurgitation.       Do not image a vena contracta in the two-chamber view as this overestimates the vena contracta    width.13   PISA The PISA method utilizes a series of measurements to produce several calculations. The most well-known is the EROA or effective regurgitant orifice area. This is different from the anatomical orifice area and produces a slightly smaller number, corresponding to the vena contracta measurement. PISA also produces the regurgitant volume (RVol) which measures the difference in mitral and aortic stroke volumes (SV), and the regurgitant fraction (RF) which is a ratio of the regurgitant volume to the forward flow across the valve.3 PISA evaluation is useful for eccentric jets but not as useful for multiple jets.3 Non-holosystolic jets may be overestimated. Adjacent valve leaks generally do not affect PISA calculations, but adjacent structural constraints may affect blood flow and therefore the PISA radius.   When imaging MR with color Doppler, as the blood flow approaches the lesion, it converges into hemispheric layers of increasing velocity and decreasing surface area. After obtaining an optimized color Doppler image of mitral regurgitation, shift the baseline on the Nyquist scale in the direction of the regurgitation to isolate the first color layer. In the transthoracic diagram (Fig. A), the change from blue to yellow denotes this first color layer change. Fig. A In a transesophageal image, the baseline shifts upwards and the first color layer change is from red to yellow.   Fig. B The PISA radius is the distance from this sharp change in color to the vena contracta (Fig. B).  This radius measurement (orange arrow) is a key component of the EROA, RVol and RF calculations. For systems that only have access to 2D PISA software, it is important to know there are caveats to 2D PISA analysis and to consider them when using the 2D PISA method. 2D PISA makes geometrical assumptions that the flow convergence has a true hemispherical shape. In reality, the flow convergence has a more hemi-elliptical shape.14 For example, if there is a regurgitant jet that lies out along the length of the commissure, a very non-hemispherical shape, the geometric assumption in the PISA calculation may underestimate the EROA or overestimate the flow volume12 In contrast, the 4D PISA calculation does not make any geometrical assumptions and provides a more accurate and reproducible  method for quantification of EROA, RVol and RF.12 The eSie PISATM volume analysis software on the ACUSON SC2000TM volume imaging ultrasound system offers both a transthoracic and transesophageal package for PISA calculations.  Example of eSie PISA analysis page    It is also important to consider the timing and duration of PISA measurements. Since regurgitation can be dynamic and the PISA calculation is an instantaneous measurement, make sure to measure the PISA radius and trace the CW Doppler VTI (volume time integral) in simultaneous cycles. Try not to combine a mid-systolic measurement with a late-systolic measurement for greatest accuracy.3 In both 2D and 4D PISA evaluation, optimization of frame rate and transducer angulation are imperative for the most accurate and reproducible calculations. It is also important to utilize a strong, full CW Doppler waveform of the regurgitant jet as well as an appropriately placed sample volume for PW Doppler waveform, sampled at the mitral annulus, of the mitral inflow. Awareness to detail in acquiring this information provides clinicians with optimal data on the severity of patient pathology.   Regurgitant jets in mitral valve prolapse are generally quite eccentric and may not produce a full CW waveform. In this case, the PISA calculation underestimates the regurgitant volume.15 In cases with multiple central jets, add together the PISA calculations from each jet.3 Download a step-by-step guide to eSie PISA analysis. Volumetric CalculationsA slightly less employed method of calculating regurgitant volume is to measure the forward stroke volume (SV) of two left-sided valves (aortic and mitral). The principle being that the stroke volume going out of the left ventricle through the aortic valve should be the same as the stroke volume coming in from the left atrium through the mitral valve. Components of Mitral Valve Stroke Volume (SVMV) calculation are: Mitral annular diameter: Measure the mitral valve annular diameter in the apical 4-chamber view. PW VTI of mitral inflow: Obtain the stroke volume of the mitral valve by sampling with PW Doppler at the level of the mitral valve annulus and tracing the VTI.   Components of LVOT Stroke Volume (SVLVOT) calculation are: LVOT annular diameter: Measure the left ventricular outflow tract diameter at the level of the aortic annulus. PW VTI of LVOT outflow: Obtain the stroke volume of the aortic valve by using PW Doppler to sample in the left ventricular outflow tract (LVOT) To obtain the regurgitant volume (Rvol), subtract the stroke volume of the mitral valve (SVMV) from the stroke volume of the LVOT (SVLVOT):   RVol = SVLVOT-SVMV   To obtain the estimated regurgitant orifice area (EROA), obtain a CW Doppler waveform of the mitral regurgitant jet and trace the VTI (VTIMR). Divide the RVol from the previous equation by the VTIMR obtained from the CW waveform:   EROA = RVol/VTIMR *Subtracting end-systolic volume from the end-diastolic volume also produces a left ventricular stroke volume for the mitral valve portion of the equation.        Volumetric methods do not work in the presence of significant aortic regurgitation.3 Use this method only in cases where PISA or vena contracta calculations are not plausible. Multiple measurements and mitral annular calcification decrease measurement accuracy.4Flow Quantification                                                                                            The newest method of calculating MR severity is through flow quantification. The 4D automated quantification of blood flow and regurgitant volume provides another parameter to the comprehensive evaluation of mitral regurgitation. The eSie FlowTM quantification package available on the ACUSON SC2000 system is validated with cardiac magnetic resonance imaging (CMR) and provides an echocardiographic method of quantifying regurgitant blood flow. The workflow for the eSie Flow package is beyond the scope of this tutorial.   Primary regurgitation is a degenerative process of the mitral leaflets, annulus or chordae tendinae3, 4 as in Barlow Disease, Marfan Syndrome, and Ehlers-Danlos Syndrome.4 Rheumatic disease is the main cause of primary MR in developing countries while in western countries it is myxomatous disease, flail leaflets and annular calcification. Other causes include endocarditis and congenital abnormalities.1   Treatment for primary mitral regurgitation involves medical management to reduce disease progression, and modification or repair to the valve apparatus.1 Modification or repair may range from complete surgical valve replacement to a percutaneous deployment of a MitraClip® or similar device.   Click on the icon below to learn more about degenerative mitral valve processes. Select ◄ to go back                                                                                                                                Select ► to continue Degenerative processes Learn more about degenerative mitral disease Slide NumberText BlocksCalloutsAudio ScriptImage File1Barlow Disease A degenerative process resulting from an abundance of excess myxomatous tissue in one or both leaflets and usually presents at a young age. The excess tissue leads to thickened leaflets with a flapping effect. It can also result in longer chordae tendinae, which interferes with coaptation. Due to these changes, the leaflets often prolapse in one or more segments.5  When finished viewing the slideshow, select the 'X' in the upper right corner to close this window.Barlow Disease A degenerative process resulting from an abundance of myxomatous tissue in one or both leaflets, and usually presents at a young age. This excess tissue leads to thickened leaflets with a flapping effect. It can also result in longer chordae tendinae, which interferes with coaptation. Due to these changes, the leaflets often prolapse in one or more segments. 2Fibroelastic Deficiency (FED) Sometimes confused with Barlow disease, fibroelastic deficiency is an abnormality in connective tissue.5 There is no excess myxomatous tissue and leaflets may appear normal on echocardiography. It often presents later in life, resulting in prolapse or flail from chordal elongation or rupture. Patients generally have a short history of mitral regurgitation.5  When finished viewing the slideshow, select the 'X' in the upper right corner to close this window.Fibro-elastic Deficiency or FED Sometimes confused with Barlow Disease, fibro-elastic deficiency is an abnormality in connective tissue. There is no excess myxomatous tissue, and leaflets may appear normal on echocardiography. It often presents later in life, resulting in prolapse or flail from chordal elongation, or rupture. Patients generally have a short history of mitral regurgitation. 3Marfan Syndrome One of several inheritable connective tissue syndromes defined by a lack of fibrillin in the elastic fibers. This results in musculoskeletal, ocular and cardiac abnormalities. Most common cardiac abnormalities include dilation, aneurysm, peripheral arterial rupture, redundant anterior mitral valve leaflet and aortic aneurysm and rupture.6When finished viewing the slideshow, select the 'X' in the upper right corner to close this window.Marfan Syndrome One of several inheritable connective tissue syndromes defined by a lack of fibrillin the elastic fibers. This results in musculoskeletal, ocular and cardiac abnormalities. Most common cardiac abnormalities include dilation, aneurysm, peripheral arterial rupture, redundant anterior mitral valve leaflet and aortic aneurysm and rupture. 4Ehlers-Danlos Syndrome (EDS) A group of inheritable connective tissue disorders identified by a lack of collagen. Symptoms of EDS include extreme joint flexibility, easy bruising, dental crowding and soft, spongy skin. Cardiovascular problems include great vessel abnormalities, mitral and tricuspid valve prolapse, and dilatation of the aortic root or pulmonary artery.When finished viewing the slideshow, select the 'X' in the upper right corner to close this window.Ehlers-Danlos Syndrome or EDS A group of inheritable connective tissue disorders identified by a lack of collagen. Symptoms of EDS include extreme joint flexibility, easy bruising, dental crowding and soft, spongy skin. Cardiovascular problems include great vessel abnormalities, mitral and tricuspid valve prolapse, dilatation of the aortic root or pulmonary artery. 5Rheumatic Disease In many parts of the world, a streptococcus infection often leads to rheumatic fever, affecting many parts of the body, including inflammation in the heart.7 Rheumatic fever directly affects the commissures, results in chordal fusion, and thickened mitral valve leaflets.5 As the pathology progresses over time, the valve becomes restricted and mitral stenosis develops.When finished viewing the slideshow, select the 'X' in the upper right corner to close this window.Rheumatic Disease In many parts of the world, a streptococcus infection often leads to rheumatic fever, affecting many parts of the body, including inflammation in the heart. Rheumatic fever directly affects the commissures, results in chordal fusion, and thickened mitral valve leaflets. As the pathology progresses over time, the valve becomes restricted and mitral stenosis develops. 6Note the difference in presentation in the two images.   The top image is of a mitral valve with FED and a ruptured chord to P3.   The bottom image is a Barlow valve demonstrating excess tissue growth and subsequent multi-segment prolapse.  Images courtesy of: Adams, David H., Rosenhek, Raphael, 2010. Degenerative mitral valve disease: best practice revolution, European Heart Journal (31)16.When finished viewing the slideshow, select the 'X' in the upper right corner to close this window.Note the difference in presentation in the two images. The top image is of a mitral valve with FED and a ruptured chord to P3. The bottom image is a Barlow valve demonstrating excess tissue growth and subsequent multi-segment prolapse. Functional or secondary mitral regurgitation is solely the result of a dilated mitral annulus, while the valve itself remains intact.8 A dilated cardiomyopathy may result from several processes including but not limited to ischemic events, infection, hypertensive disease, infiltrative disease and pharmaceutical toxicity.5 The left ventricle remodels to accommodate loss of myocardial function, stretching the mitral annulus and reducing leaflet coaptation. This creates a large orifice for blood to flow back through in ventricular systole. In the case of ischemia, the posteromedial papillary muscle often apically displaces. Since the chordae are now restricted, the mitral valve leaflets can no longer coapt at the level of the mitral annulus and regurgitation develops. In addition to papillary muscle displacement, ischemic events often lead to other sources of poor mitral valve coaptation, including dilated and flattened annulus.5                               Clinicians direct treatment for secondary MR at improving cardiac function through medical management.8 The goal is to unload the left ventricle, improving  cardiac performance and reducing the amount of MR. If these methods do not prove successful, surgical intervention may be required.8 Some of the challenges patients with functional MR face in the course of surgical intervention include multiple comorbidities and an elderly population. Select ◄ to go back                                                                                                                            Select ► to continue  The following table summarizes the imaging techniques, considerations and limitations of the multiple methods of MR quantitative evaluation:     Technique Optimization Considerations Limitations Vena contracta •Parasternal long axis view •Narrow sector and zoomed view for optimum frame rate •Useful for eccentric jets •Good for separating mild and severe •Independent of flow and pressure variations •Not as useful with multiple jets •Over estimates non-holosystolic jets •Convergence zone must be well visualized PISA •Obtain PISA in apical 4-chamber •Parallel to flow, Zoomed view •Adjust baseline direction of flow until PISA is visible •Measure PISA in mid-systole from point of aliasing to vena contracta •Obtain MR VTI, MV inflow VTI •No proximal flow convergence generally signifies mild MR •Useful for eccentric jets •Produces EROA and RVol calculations •Not affected by MR etiology or concurrent valve leaks •Not useful for multiple jets •Convergence zone must be well-visualized •Overestimates non-holosystolic jets •PISA shape affected by orifice shape, aliasing velocity, regurgitant flow systolic changes and constraining adjacent structures •PISA errors are squared •2D PISA calculations makes geometric assumptions Volumetric Methods •Obtain MV VTI at the mitral annulus •Measure MV annulus diameter in apical 4-chamber •Obtain LVOT VTI just below annulus •Obtain LVOT diameter in parasternal long axis •Useful for multiple jets •Produces EROA and RVol calculations •Multiple measurements increase chances of error •Not applicable with significant aortic regurgitation •Calcified mitral annulus prohibits accurate MV annular diameter measurement   Select ◄ to go back                                                                                                                            Select ► to continue *Echocardiographic images in this tutorial are compliments of :   Manni Vannan, MD Piedmont Heart Institute http://www.piedmont.org/locations/piedmont-atlanta/pah-home   *Unless otherwise cited. Select the icons below for additional information. Glossary Glossary ASE American Society of Echocardiography Barlow Disease A degenerative process resulting from an abundance of myxomatous tissue, usually leading to prolapse. CMR Cardiac Magnetic Resonance Imaging Ehlers-Danlos Syndrome (EDS) A group of inheritable connective tissue disorders identified by a lack of collagen and often leading to prolapse. EROA Effective Regurgitant Orifice Area is a ratio of the regurgitant volume to the velocity time integral.  ESC European Society of Cardiology Fibroeslastic Deficiency (FED) Fibroelastic Deficiency is an abnormality in connective tissue, which generally leads to leaflet prolapse. Flail Describes the motion of a mitral leaflet or scallop when it loses its integrity and floats back into the atrium. Marfan Syndrome A connective tissue disorder from a lack of fibrillin in the tissue fibers. Primary MR Also known as degenerative MR, results from a structural or anatomical abnormality of the mitral valve or chordae. Prolapse Coaptation of one or both of the mitral leaflets beyond the annular plane. Regurgitant Fraction (RF) A ratio of the regurgitant volume to the forward flow across the valve. Regurgitant Volume (RVol) The difference between the mitral and aortic stroke volumes. Restriction Describes the limited motion of one or both mitral leaflets, generally resulting from mitral stenosis. Secondary MR Also known as functional MR, results from dilatation or stretching of the mitral annulus. Stroke Volume (SV) A volumetric flow measurement derived from the cross-sectional diameter multiplied by the VTI. Tenting Describes the modified coaptation of the mitral leaflets, generally due to dilatation of the annulus from ischemic cardiomyopathies. TTE Transthoracic echocardiogram TEE/TOE Transesophageal echocardiogram Velocity Time Integral (VTI) Doppler waveform tracing depicting mean velocity. (Also known as Time Velocity Integral or TVI.) Reference List Reference List 1. Enriquez-Sarano, M., Akins, C. W., & Vahanian, A. (2009). Mitral regurgitation. Lancet, 373(9672), 1382-1394. doi: 10.1016/S0140-6736(09)60692-9   2. Lang, R., Goldstein, S. Kronzon, I. Khanderia, B. Mor-avi, V. (2016). Quantification of Mitral Regurgitation ASE's comprehensive Echocardiography. Philedelphia: Elsevier.   3. Zoghbi, W. A., Adams, D., Bonow, R. O., Enriquez-Sarano, M., Foster, E., Grayburn, P. A., . . . Weissman, N. J. (2017). Recommendations for Noninvasive Evaluation of Native Valvular Regurgitation: A Report from the American Society of Echocardiography Developed in Collaboration with the Society for Cardiovascular Magnetic Resonance. J Am Soc Echocardiogr, 30(4), 303-371. doi: 10.1016/j.echo.2017.01.007   4. 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