Study for the Examination of Special Competence in Advanced Perioperative Transesophageal Echocardiography, (Advanced PTEeXAM^®)

 

The Mitral Valve Complex Components

 

Approach to Mitral Valve TEE Assessment

• Always complete a full 2D assessment before you turn on the color Doppler

• Goal: Establish the mechanism of disease and its hemodynamic impact first

• Look for indirect signs of severe or long-standing disease:

  • Chamber enlargement (LA or LV)

  • Indirect signs of pulmonary hypertension (PH)

• 3D views are great, but systematic 2D views are the foundation for mental reconstruction of the valve

 

Midesophageal Four-Chamber View (ME 4C)

• Position: Obtain at 10 to 20 degrees by gently retroflexing the probe

• Orientation: Sector is directed toward the cardiac apex through the MV

  • Left of screen: A3 segment (anterior leaflet)

  • Right of screen: P1 scallop (posterior leaflet)

• Sweeping the valve to find pathology:

  • Withdraw or anteflex the probe slightly to see the anterolateral commissure and LVOT (Left Ventricular Outflow Tract)

  • Advance or retroflex the probe slightly to see the posteromedial commissure

• At 0 degrees, you are often in a 5-chamber view seeing the middle A2 segment and anterior P2

 

Midesophageal Mitral Commissural View (ME COMM)

• Position: Rotate the multiplane angle forward to approximately 60 degrees

• Orientation: Aligns the imaging sector with the mitral valvar commissures

  • Left of screen: P3 scallop

  • Right of screen: P1 scallop

  • Middle: A2 segment (moves in and out of view as the valve cycles)

• Best use: This view is ideal for localizing the origin of MR (Mitral Regurgitation)

• Tip: Use small left and right probe rotations to move the scanning plane across the coaptation line

 

Midesophageal Two-Chamber View (ME-2C)

• Position: Advance the multiplane angle to 90 degrees

• Orientation: Cuts the valve at an oblique angle relative to the commissures

  • Right of screen: Anterior parts (A2 and A1)

  • Left of screen: Posterior parts (P3)

• Scan the whole valve by using small left and right rotations of the probe

• Safety Check: This is also the primary view to evaluate the LAA (Left Atrial Appendage) for thrombi

 

Midesophageal Long-Axis View (ME LAX)

• Position: Multiplane angle set between 120 and 140 degrees

• Visuals: Shows the Aortic Valve (AV) in long axis along with the MV

• Anatomy:

  • Imaging plane is perpendicular to the coaptation line

  • Shows the aortomitral continuity (fibrous connection)

  • Shows the full length of A2 and P2

• Turn the probe right (clockwise) to see A3/P3 and left (counterclockwise) to see A1/P1

 

Quantitative Measurements in the ME LAX View

• This is the best view for measuring the Vena Contracta (VC) diameter

  • Why: The imaging plane must be perpendicular to the coaptation line for an accurate systolic measurement

• Use this view to measure the Annular Interpeak Distance (Anterior to Posterior diameter)

• Excellent for assessing LVOT pathology or subaortic valve issues

 

Transgastric Basal Short-Axis View (TG Basal SAX)

• Position: Withdraw the probe from the midpapillary view while keeping it flexed

• Orientation:

  • Far field/Right of screen: Anterolateral commissure plus A1/P1

  • Near field/Left of screen: Posteromedial commissure plus A3/P3

• Benefit: Highly helpful for identifying the origin of a regurgitant jet

• Caveat: You cannot accurately quantify pathology with color Doppler in this specific view

 

Transgastric Two-Chamber View (TG 2 CH)

• Position: Advance the multiplane angle to 90 degrees from the basal short-axis

• Focus: Evaluation of the subvalvular apparatus (chordae and papillary muscles)

  • Near field: Posteromedial papillary muscle

  • Far field: Anterolateral papillary muscle

• This is the best view for chordae because they are perpendicular to the ultrasound beam, giving you the clearest resolution

 

Optimizing Doppler Assessment

• Goal: Achieve high temporal resolution (frame rate)

• Technique: Keep the 2D and color Doppler sectors as small as possible

  • Ensure the sector is still large enough to include the whole area of interest

• Settings: Aim for a frame rate of at least 15 frames per second

• Application:

  • Use Color to find MR (systole) or MS (Mitral Stenosis) (diastole)

  • Use PWD (Pulsed-Wave Doppler) and CWD (Continuous-Wave Doppler) to quantify the severity of the disease

 

3D Image Acquisition and Manipulation

• How to start: Obtain a clear 0, 60, 90, or 120 degree 2D view first

• Use Biplane Mode: Confirms the full annulus is included and centered in two orthogonal views

• Acquisition Options:

  • Live mode: Good for quick looks, but lower resolution

  • Multibeat: Preferred for better spatial and temporal resolution

• Standard Display: Position the AV at the top of the image

  • This provides the En Face view (the "surgeon's view") from the LA side

 

Clinical Value of 3D Assessment

• Provides incremental value in localizing pathology during repair procedures

• Allows more accurate quantification of:

  • EROA (Effective Regurgitant Orifice Area)

  • Mitral valve area in MS

  • Vena contracta and annular geometry

• Postoperative Quality Assurance:

  • Excellent for visualizing annuloplasty rings, bands, or prosthetic valves

  • Easily confirms the location and severity of paraprosthetic leaks (leaks around the valve cuff)

 

 

Mitral Regurgitation: Definition and Hemodynamics

• Mitral Regurgitation (MR) results from incomplete closure of the mitral valve leaflets during left ventricular (LV) systole

• This leads to backflow of blood into the left atrium (LA)

• The severity of the backflow depends on:

  • Regurgitant orifice area (the most important factor)

  • Duration of systole

  • Pressure gradient between the LV and the LA

• To keep the valve competent, you need normal size and function of the leaflets, chordae, annulus, LV, and LA

  • Dysfunction in any of these parts can cause MR

 

Primary vs. Secondary Mitral Regurgitation

• Secondary (Functional) MR:

  • The valve leaflets and chordae are actually normal

  • The problem is changes in LV geometry (dilated cardiomyopathy or ischemia)

  • The LV pulls the leaflets apart so they cannot meet (malcoaptation)

• Primary (Organic) MR:

  • The problem is in the valve structure itself (leaflets, chordae, or papillary muscles)

  • Causes include:

    • Degenerative disease (Myxomatous degeneration or fibroelastic deficiency)

    • Connective tissue disorders (like Marfan syndrome)

    • Infective endocarditis (leaflet destruction)

    • Papillary muscle rupture (usually after an MI)

    • Rheumatic heart disease

 

Mechanisms of Mitral Incompetence: The Carpentier System

• Valve repair is the preferred method over replacement because it has better outcomes

• You must understand the mechanism of the leak to plan a repair

• The Carpentier functional classification describes how the leaflets move during opening and closing:

  • Type I: Normal motion

  • Type II: Increased motion (prolapse or flail)

  • Type III: Restricted motion

• Use Color Doppler to check the jet direction and origin as it reveals the underlying mechanism

 

Carpentier Type I: Normal Leaflet Motion

• The leaflets move normally, but there is still a leak

• Etiology:

  • Annular dilatation: Usually results in a central regurgitant jet

  • Leaflet perforation: The jet originates from the hole in the leaflet, not the coaptation line

  • Clefts: Jet direction varies based on the defect location

 

Carpentier Type II: Increased Leaflet Motion

• The leaflets move beyond the level of the annulus into the LA

• Causes:

  • Chordal rupture: Results in a flail leaflet

  • Elongated chordae: Results in a prolapse

• Jet Direction: Usually directed away from the pathological leaflet

  • Example: Posterior leaflet prolapse creates an anteriorly directed jet

• Timing: The MR often worsens during the latter part of systole

• Note: In Barlow disease (multisegment prolapse), the jet might look central

 

Carpentier Type IIIA: Restricted Motion (Systole and Diastole)

• Leaflet motion is limited during both the opening and closing phases

• Usually the result of Rheumatic Heart Disease

• Clinical finding: This is rarely seen alone; you will usually see some degree of Mitral Stenosis as well

• Jet Direction: Typically eccentric and directed toward the restricted leaflet

  • If both leaflets are equally scarred, the jet may be central

 

Carpentier Type IIIB: Restricted Motion (Systolic Only)

• The leaflets are restricted primarily during systole

• Usually seen in Dilated Cardiomyopathy

• Mechanism:

  • The enlarged LV and displaced papillary muscles pull the leaflets toward the apex (tethering)

  • This leads to "tenting" and poor coaptation

• Jet Direction: Typically central

• Note: This is a ventricular problem, not a primary valve problem

 

Carpentier Type IIIC and Type IV

• Type IIIC (Asymmetric Restricted Motion):

  • Restricted motion due to localized ventricular pathology (like an ischemic wall motion abnormality)

  • Results in focal tethering of one leaflet

  • Jet is directed toward the afflicted leaflet

• Type IV: Systolic Anterior Motion (SAM):

  • The anterior leaflet is "sucked" into the Left Ventricular Outflow Tract (LVOT)

  • Causes dynamic obstruction and dynamic MR

  • Jet Direction: Usually directed inferolaterally

  • Causes: Hypertrophic cardiomyopathy, post-repair complications, or even severe hypovolemia with high inotropes

 

Assessment of MR Severity: 2D Imaging

• Check the valve structure: Significant MR is rare in a "normal" looking valve

• Look for secondary changes:

  • LV Dilatation: Chronic MR causes volume overload and eccentric hypertrophy

  • LA Dilatation: Elevated pressure leads to a bigger atrium, which increases the risk for Atrial Fibrillation(clot risk)

  • Pulmonary Hypertension: Severe MR eventually backs up into the lungs and right heart

• If you see these structural changes, you should suspect the MR is significant

 

Color Doppler: The Jet Area Method

• How to do it:

  • Adjust scale to 50-70 cm/s

  • Set gain to just below the point of "speckle"

• Why this method is NOT recommended for grading:

  • Underestimation: "Wall-hugging" jets (Coanda effect) appear smaller than they are

  • Overestimation: High driving pressures (like systemic hypertension) can make a small leak look huge

• Best use: Most helpful for central jets to get a quick visual impression

 

Vena Contracta (VC): The "Gold Standard" for 2D

• The VC is the narrowest part of the jet just distal to the anatomical orifice

• It represents the actual regurgitant orifice

• Technique:

  • Use a view perpendicular to the coaptation line (ME long-axis)

  • Zoom in on the valve

  • Set color scale to 50-70 cm/s

  • Narrow the color sector to improve resolution

• Advantages:

  • Less affected by loading conditions

  • Works for eccentric jets

• Limitations: Less useful if there are multiple jets or if the orifice is oval (common in secondary MR)

 

3D Echocardiography and Vena Contracta

• 3D Transesophageal Echocardiography (TEE) allows you to see the cross-sectional area of the VC

• You can use direct planimetry (tracing the area)

• Benefits:

  • Outperforms standard 2D methods

  • Correlates well with Cardiac MRI

  • Solves the "oval orifice" problem in secondary MR

 

Pulsed-Wave (PW) Doppler: Transmitral Inflow

• High-grade MR leads to high LA pressure, which forces blood across the valve faster in early diastole

• Place the PW sample at the mitral leaflet tips

• Severe MR findings:

  • E-wave velocity > 120 cm/s

  • Note: If the A-wave is dominant (A > E), you can generally exclude severe MR

• This only works if there is no Mitral Stenosis present

 

MV to AV Velocity Time Integral (VTI) Ratio

• This compares flow across the Mitral Valve (MV) to flow across the Aortic Valve (AV)

• In MR, the forward flow across the MV must increase to compensate for the leak

• How to calculate:

  1. Trace the PW spectral Doppler of transmitral inflow (MV VTI)

  2. Trace the PW of the LVOT ejection (AV VTI)

• Grading:

  • Ratio > 1.4: Typically indicates Severe MR

  • Ratio < 1.0: Indicates Mild MR

 

Pulmonary Venous Flow Patterns

• Interrogate the pulmonary veins with PW Doppler

• Normal flow: Dominant systolic component

• Moderate MR: Systolic blunting (the systolic wave gets smaller)

• Severe MR: Systolic flow reversal (blood flows backward into the vein during systole)

• Caveats:

  • Atrial fibrillation and diastolic dysfunction can also cause blunting

  • Eccentric jets can "blow" into one specific vein, causing reversal even if the MR isn't globaly severe

 

Continuous-Wave (CW) Doppler Characteristics

• CW Doppler gives qualitative clues about the jet

• Density: A dense (dark/filled-in) spectral display suggests more significant MR

• Shape:

  • A symmetric, parabolic shape is standard

  • An early peak with a "cutoff" appearance in late systole suggests a rapid rise in LA pressure, seen in Severe MR

 

The Continuity Equation for Regurgitant Volume

• Forward flow through a leaky valve = Effective forward stroke volume + Regurgitant volume (RVol)

• Step 1: Calculate LVOT Stroke Volume (SV)

  •  SV LVOT​  =  Area LVOT​  ×  VTI LVOT​ 

• Step 2: Calculate Mitral Valve Stroke Volume (SV MV)

  •  SV MV​  =  Area annulus​  ×  VTI annulus​ 

• Step 3: Find the difference

  •  RVol =  SV MV​  −  SV LVOT​ 

• Regurgitant Fraction (RF):

  •  RF =  (RVol/SV MV​ ) ×  100 OR

  •  RF =  ((SV MV​  −  SV LVOT​)/SV MV​ ) ×  100

• Limitation: This is difficult in Atrial Fibrillation because the stroke volume changes every beat

 

Proximal Isovelocity Surface Area (PISA) Method

• As blood approaches the tiny hole, it speeds up, forming concentric hemispheres of increasing velocity

• The Principle: Flow through any hemisphere = Flow through the regurgitant orifice

• Technique:

  1. Zoom on the valve with color Doppler

  2. Shift the baseline in the direction of the jet (usually down) to make it "alias"

  3. Measure the Radius (r) from the orifice to the first color change

  4. Note the Aliasing Velocity (Va) from the scale

• Formula for EROA:

  •  EROA =  (6.28 ×  r 2 ×  Va)/V max​  (where Vmax is from CW Doppler)

 

PISA Limitations: What to Watch For

• Non-circular Orifices:

  • The formula assumes a perfect circle

  • Secondary MR is often oval, so 2D PISA usually underestimates the severity

• Dynamic Orifices:

  • The size of the leak can change throughout systole

  • In Prolapse, the PISA is biggest at the end of systole

  • In Secondary MR, the PISA might be biggest at the start and end of systole

• Wall Constraint:

  • If the jet is very large and hits the LV wall, the hemisphere shape is distorted

  • This can lead to an overestimation of severity

 

Final Grading: The Integrated Approach

• Never rely on just one number

• You must combine:

  • 2D findings (Is the LA/LV dilated?)

  • Color flow (VC width, PISA)

  • Doppler (Pulmonary vein reversal, VTI ratios)

• Acute vs. Chronic:

  • A sudden chordal rupture can cause severe MR without a dilated LV/LA

  • The patient will be in flash pulmonary edema because the small LA cannot handle the pressure

• Severe MR Cutoffs (Primary):

  • VC Width: > 0.7 cm

  • RVol: > 60 mL

  • EROA: > 0.40 cm²

 

 

 Mitral Stenosis: Hemodynamics and Clinical Impact

• Normal Mitral Valve Area (MVA) is 4 to 5 cm²

• Symptoms usually start once the MVA is less than 2.5 cm² because you need a higher pressure gradient to keep blood moving

• Pathophysiologic Chain Reaction:

  • Increased Left Atrium (LA) pressure leads to atrial enlargement

  • Enlargement triggers Atrial Fibrillation (A-fib)

  • Loss of atrial "kick" and rapid heart rates cause sudden worsening of symptoms

  • Pressure backs up into the lungs causing Pulmonary Hypertension (PH)

  • PH eventually leads to Right Ventricle (RV) dysfunction and functional Tricuspid Regurgitation (TR)

• Be on the lookout for LA thrombi (clots) and embolic events, especially if the patient has A-fib or low cardiac output

 

Rheumatic Mitral Stenosis: The Most Common Cause

• Mechanism: A progressive inflammatory reaction in the valve tissue

• Key Findings:

  • Leaflet tips thicken and anterior/posterior leaflets fuse at the commissures

  • Chordae tendineae become thickened and shortened, which restricts leaflet movement

  • Calcification can eventually involve the entire leaflet body and base

• Important Note: Rheumatic disease often causes Mitral Regurgitation (MR) to happen at the same time as stenosis

• Systemic Check: Rheumatic disease rarely hits only the mitral valve; you should carefully check the Aortic and Tricuspid valves for damage or vegetations

 

Non-Rheumatic and Rare Causes of MS

• Degenerative Calcification:

  • Usually starts in the mitral annulus and is rare as a primary cause

  • Associated with diseases like Systemic Lupus Erythematosus (SLE), hypertension, or hyperparathyroidism

• Congenital MS:

  • Rare and typically seen in children

  • Parachute Mitral Valve: All chordae go into a single papillary muscle, choking off diastolic flow

• Atrial Myxoma:

  • This is an intracardiac tumor that can physically block the valve

  • Warning: It may cause intermittent signs of MS depending on how the tumor moves

 

2D Visual Clues: What to Look For

• Rheumatic Appearance:

  • Look for the classic "hockey stick" appearance where the anterior leaflet bows or domes during diastole

  • Use the transgastric two-chamber view to see if the subvalvular apparatus (chordae) is calcified or shortened

• Degenerative Appearance:

  • You will see annular calcification extending into the leaflets

  • The posterior leaflet is usually affected more than the anterior one

• LA Assessment:

  • Check for Spontaneous Echo Contrast (sludge-like appearance) which signals sluggish flow and a very high risk for clots

 

Secondary Effects: RV Pressure Overload

• Pulmonary Hypertension (PH):

  • Use Continuous-Wave (CW) Doppler on the TR jet to calculate systolic RV and pulmonary artery pressures

• Interventricular Septum Changes:

  • In severe cases, the high pressure in the RV pushes the septum toward the left

  • Look for a D-shaped Left Ventricle (LV) in the transgastric midpapillary short-axis view

• PH degree varies wildly between patients and doesn't always tell you how small the valve area is, but it is critical for surgical timing

 

Mitral Valve Area by Planimetry: Your Reference Standard

• How to perform:

  • Use a zoomed transgastric short-axis view

  • Align your tomographic plane exactly at the level of the leaflet tips (the smallest opening)

  • Scroll through the loop to find the frame with the largest area in mid-diastole

• Best Practices:

  • Adjust your gain carefully: If you "overgain" the image, the hole looks smaller than it is, leading to underestimation of MVA

  • Avoid the atrial side: Measuring on the atrial side of the funnel-shaped valve will overestimate the MVA

• Benefit: This method correlates best with the actual size of the valve orifice

 

3D Echocardiography: Ensuring Accuracy

• Why use 3D:

  • Standard 2D can miss the "true" narrowest part of the funnel

  • 3D datasets allow you to use multiplane processing to ensure you are measuring at the exact level of the smallest orifice

• Results:

  • MVA obtained by 3D is consistently smaller (and often more accurate) than 2D planimetry or Pressure Half Time calculations

 

Mean Transvalvular Gradient: Measuring Flow Pressure

• Technique:

  • Use CW Doppler to capture the highest velocities

  • Use the simplified Bernoulli equation:  ΔP =  4v 2

  • Use the view that offers the best parallel alignment with the flow direction

• Warning Factors:

  • Gradients depend on heart rate and cardiac output

  • High flow (like coexisting MR) will increase the gradient

  • Low flow (low cardiac output) will decrease the gradient, potentially masking severity

• A-fib: If the heart rate is irregular, you must average the gradients over at least five cardiac cycles with similar R-R intervals

 

Mitral Valve Area by Pressure Half Time (P1/2t)

• The Concept:

  • Pressure drops between the LA and LV during diastole

  • In MS, this drop is slow because the valve is narrow

  • The severer the stenosis, the longer it takes for the pressure to drop

• How to calculate:

  •  MVA =  220/(P 1/2​ t)

• How to do it on the machine:

  • Draw your deceleration slope from the peak velocity

  • If you see two different slopes, use the second, flatter slope in the latter part of diastole for the calculation

 

Pitfalls of the P1/2t Method

• Compliance Issues:

  • This method is very sensitive to how "stiff" the LA and LV are

  • LV diastolic dysfunction (common in older or hypertensive patients) will make the calculation inaccurate

• Aortic Regurgitation (AR) Impact:

  • Underestimation: Significant AR fills the LV from the "back door," making the pressure drop too fast and making the MS look milder than it is

  • Overestimation: If an AR jet physically hits the mitral leaflet, it prevents it from opening fully

• This method is only validated for native valves; do not use it for bioprosthetic or mechanical valves

 

MVA by Continuity Equation

• The Rule: What flows in must flow out ( MVSV =  LVOT SV​ )

• The Formula:

  •  MV Area​  =  (LVOT CSA​  ×  LVOT VTI​ )/MV VTI​ 

• Contraindications (When NOT to use):

  • Atrial Fibrillation: Measurements are taken during different beats, so they won't match

  • Valvular Incompetence: Do not use if there is significant MR or AR, as the forward flow across the valves is no longer equal

 

MVA by Proximal Isovelocity Surface Area (PISA)

• Technique:

  • Look for the "hemispheres" on the atrial side of the valve

  • Shift your color baseline in the direction of flow to induce aliasing

• Angle Correction Required:

  • Because the mitral valve is funnel-shaped, the surface isn't a perfect hemisphere

  • You must apply an angle correction ($\alpha$) based on the opening angle of the leaflets

• Main Advantage: This method works even if there is significant Mitral Regurgitation present

• Limitation: Highly inaccurate in A-fib because  V max​  and PISA radius are measured on different beats

 

Grading Mitral Stenosis Severity

• Integrated Approach: You should perform Planimetry, P1/2t, and Mean Gradient for every patient

• Reference standard: If measurements disagree, use Planimetry (if image quality allows)

• Grading Table: