Mitral Valve Disease & Mitral Regurgitation

• Mitral Valve Disease focuses on Mitral Regurgitation (MR).
• Objectives include analyzing echo abbreviations, listing MR causes, analyzing MR severity, and listing echo views used to assess MR.
• Further objectives are describing normal vs. abnormal MV motion, how MR develops, echo findings in MV prolapse (MVP).
• Additionally, objectives include listing medical procedures for MR correction and describing MR-associated signs and symptoms.

ASE Guidelines and Standards

• Recommendations for Noninvasive Evaluation of Native Valvular Regurgitation were developed in collaboration with the Society for Cardiovascular Magnetic Resonance.
• A report from the American Society of Echocardiography.

MR Etiology (Causes) & Types

• Primary MR is due to MV myxomatous, degenerative and inflammatory changes or from infectious, congenital issues, papillary muscle rupture.
• Secondary MR arises from Ischemic or Nonischemic issues.
• Prolapse is the most common, flail, elongation of the chordae
• Annular dilatation is degenerative.

Clinical Signs & Symptoms

• Chronic MR is progressive disease of MV and/or LV, symptoms usually absent at rest.
• Dyspnea or SOB presents particularly with exercise (DOE-dyspnea on exertion).
• Acute MR may result from chordae/papillary muscle rupture, causing severe dyspnea at rest.
• Emergent respiratory distress may occur, requiring intubation.

Cardiac Auscultation

• Murmurs can indicate heart sounds and defects.
• A blowing, high-pitched, holo-systolic murmur at apex indicates LV flow.
• Small amounts of MR are typically not heard.
• A mid-to-late systolic "click" (and murmur combo) indicates MVP due to chordal tension.
• "Click" is a heart sound, not a murmur.

Transesophageal Echo (TEE)

• TEE visualizes cardiac valves and assesses valve morphology, hemodynamics, and function.
  

• TEE transducers are are 2-3 mm from the heart.
• TEE provides better valve visualization and is used to rule out clots in the LA and dissection/thrombus in the aorta.

Structural Findings Associated with MR

• The severity of MR can be assessed using mitral valve morphology, LV and LA size, and Qualitative Doppler.
• Color flow jet area, flow convergence, and CWD jet are Qualitative Doppler factors
• Quantitate severity using VCA, pulmonary. Mitral inflow and EROA. RVol and RF

PLAX View: Normal MV

• Assess leaflet thickness, excursion, and coaptation surface line in PLAX view.
• Pan through the valve (RVI/RVO) to rule out abnormalities.
• This applies to all valve interrogation.

MV Apparatus Evaluation: Panning

• The apparatus includes papillary muscle, chordae tendineae, leaflets, and annulus.
• Zoom to pan (sweep) through the valve.

Mitral Valve Prolapse (MVP) (AKA: Myxomatous Valve Dz)

• Valve leaflets bulge/bend into LA during ventricular contraction, resulting in leakage of blood.
• MVP is often a congenital genetic disorder from myxomatous degeneration.
• 2-5% of the population may have MVP
• MVP may cause chest pain and palpitations or be asymptomatic.

M-Mode of MV

• Leaflet closure line is flat and is normal
• The leaflet closure line is concave in MVP

MVP Diagnosis

• A doctor may hear a systolic murmur and/or "click" heart sound.
• Both are heard in late-systole if regurgitation present.
• TTE is ordered and sonographer identifies if valve is redundant/excessive.
• MV leaflets displace upwards beyond the annular plane into LA in MVP.
• Further the leaflets displace results in more severe MVP.

MVP Severity Assessment

• Mild MVP demonstrates slight leaflet displacement beyond the annular plane.
• Severe MVP shows significant leaflet displacement beyond the annular plane.

Treatment for MVP

• Surgery is not required unless symptomatic: dyspnea, significant MR, chamber dilation & elevated PASP.
• Serial TTE assesses MR severity and chamber size.
• Beta-blockers prescribed for symptomatic pts with palpitations/high HR if no significant MR present.

Partial Flail Posterior Leaflet

• The protocol is to evaluate leaflet thickening and the coaptation (closure) surface line.
• Panning through the valve (RVI/RVO) to find the flail is required.
• Significant MR is usually present.
• If one leaflet is involved, MR most likely will be eccentric.

Ischemic CM Causing Incomplete Mitral Leaflet Closure (IMLC)

• Leaflets do not coapt at annular plane, creating tenting effect due to papillary muscle displacement.
• Chordae can only stretch so far, the valve does not fully close, resulting significant MR.
• MR is a central jet, but can be eccentric also.

Mitral Annular Calcification (MAC)

• MAC is abnormal, developing with aging, MAC encroaches upon the leaflets restricting mobility.
• MAC is echo-bright structure at posterior annulus
• Determine if it’s MV repair.

2D Assessment of the MV Leaflets

• Pan until all parts of the leaflet are visualized, Three sections classified as A1/P1 which is Central, then, A2/P2 (lateral), and A3/P3 (medial).
• P2 is most common with Mitral Valve Prolapse (MVP80%).

3D Assessment of the MV Leaflets

• 2D images are from Apex up
• 3D images are from LA downwards also called surgeon's view

Qualitative Doppler for the Severity of Chronic MR

• The severity is graded as mild, moderate, or severe based on several qualitative and quantitative factors.
• Structural assessment includes MV morphology and LV/LA size.
• Doppler assessment involves color flow jet area, flow convergence, and CWD jet characteristics.
• Semiquantitative VCW (cm), quantitative flow and EROA, RVol, and RF are key to quantifying.

Color Doppler Assessment of MR

• Pan through the valve (RVI/RVO) to look for the origination of MR.
• Increase color gain until aliasing, reduce gain
• Decrease color sector size until all the MR is fully visualized.
• This applies to all valve interrogation.

Flow Convergence (FC) & Area

• Flow convergence assessed with the flow convergence area of the mitral inflow

Color Doppler M-mode of MR

• This allows for assessment for the Timing and Etiology

SIQ Valve Assessment

• The assessment of the valve with SIQ

Color Doppler / M-mode Assessment of MR in MVP

• MVP typically associates with some degree of MR.
• Because valve breaks the annular plane during mid-to-late systole, timing of MR is the same.

No MVP Comparison

• Displays the PW for a normal heart
• The image displays Pan-Systolic MV

CW Doppler Profile

• Inspect the density, duration (typically holo/pan systolic, occupying isovolumic periods).
• Note timing (MVP is late-systole).
• Observe shape (typically symmetric/parabolic but V-shape indicates severe MR/high LAP).

All Shapes and Sizes

• Displays All Shapes and Sizes

Comparison of Display and Timing in MR Using Color Doppler, and Color M-mode

• Assessment of using color doppler and M-mode

Comparison of Display and Timing in MR Using CW Doppler and Color Doppler

• Assessment of when to use CW for timing

Grading the Severity of Chronic MR

• It can be graded using structural information, qualitative doppler, semiquantitative, or quantitative means

Vena Contracta (VC)

• VC is measured the dimension of the narrowest portion of a jet at or downstream from the orifice.
• High velocity is laminar flow.
• Measure VC to quantify, Mild <0.3, Mod from 0.3-0.69, Severe >= 0.70

PW Doppler in Significant MR

• Presents a predominant early filling with severe MR
• Presents a mitral E wave velocity > 1.2 - 1.5 m/sec consistent with severe MR, rule out co-existing stenosis
• Must notate its is restrictive filling pattern.

Pulmonary Vein Doppler Assessment

• Assessment usually seen in severe MR, with blunted S, tall D Usually seen with systolic reversal (aliasing)

Technical Tip: Optimal Gain

• Setting the gain to optimal is important

MR All Shapes and Sizes

• The image shows different examples

Use of MR Slope for Estimating LV Systolic Performance (dP/dt)

• Measurements that that change in pressure can estimate LV Systolic Performance
• Measure onset of the MR slope at 1 meter and extrapolate to 3 meters.Normal is > 1200 mmHg/s
• EF 15-20%