Diastology

Diastolic Dysfunction Grader

Start with e’, then use mitral inflow and filling pressure markers to grade severity.

1

Septal e’

Is septal e’ ≤ 6 cm/s?

2

Mitral inflow

Select the E/A pattern.

3

E/e’

Is E/e’ elevated?

4

TR velocity / RVSP

Is TR velocity elevated?

Optional

Supportive markers

Use these when the core data are discordant or borderline.

Result

Select inputs above

Start with septal e’. If e’ is normal, diastolic function is usually normal. If e’ is low, use E/A pattern and filling pressure markers.

Filling pressure Not enough data
Confidence Not enough data

    Core Elements

    • Mitral annular tissue Doppler
    • Mitral inflow Doppler
    • E/e’
    • Right ventricular systolic pressure
    • Left atrial volume index
    • Left atrial strain
    • Pulmonary vein Doppler

    Tissue Doppler- Do they have diastolic dysfunction?

    Mitral annular motion reflects LV relaxation.

    • Septal e’ velocity < 6 cm/s is abnormal
    • Lateral e’ < 7 cm/s can also be used, but septal e’ is preferred and easier to measure
    • If e’ is normal, the patient almost certainly has normal diastolic function and you are essentially done with diastology
      • This is by far the most important measurement

    Tissue Doppler Velocities

    • s’ = LV systolic annular velocity
    • e’ = early diastolic annular velocity, reflecting LV relaxation
    • a’ = late diastolic annular velocity, reflecting atrial kick/late LV filling

    How to Measure Medial e’

    • Measure the bright modal envelope
    • Avoid measuring artifact
    • Measure the e’ envelope nearest to the a’ wave
    • The preceding wave measured at 4 cm/s is isovolumetric relaxation and is not e’
    • In this example, e’ < 6 cm/s, consistent with impaired relaxation

    Mitral Inflow Doppler- How severe is their diastolic dysfunction?

    • Measure using PW doppler at the mitral leaflet tips
    • If e' is abnormal, mitral inflow velocity helps grade the severity of diastolic dysfunction

    Normal

    • E > A
    • E/A > 0.8
      • LV relaxes, pressure decreases and pressure rushes from high to low pressure area composing the majority of LV filling (E wave) with small component from atrial kick (A wave)

    Grade I: Impaired Relaxation

    • A > E
    • E/A < 0.8
    • Usually long deceleration time (> 240ms)
      • LV is stiff so when MV opens, no longer low pressure in LV in early diastole so lower amplitude of E wave/slower deceleration time and more reliant on atrial kick to fill the LV but LAP normal

    Grade II: Pseudonormal

    • E > A
    • E/A 0.8-2.0
    • e’ is abnormal, so you know the apparently normal E/A pattern is actually abnormal
      • LV is stiff but LAP is high enough to push blood out into the ventricle in early diastole

    Grade III: Restrictive Filling

    • E >> A
    • E/A > 2.0
    • Usually short deceleration time (< 160ms)
      • LAP keeps climbing and get more rapid/early diastolic filling with very short deceleration time with very little atrial filling 

    Deceleration time

    • Measured from peak E wave to return to baseline
      • Normal: 160-240ms
      • Long DT > 240ms = impaired relaxation/grade I pattern
      • Short DT < 160ms = restrictive filling / high LA pressure

    E/e’ Ratio- What is their filling pressure?

    • E is taken from pulse wave Doppler mitral inflow
    • e’ is taken from tissue Doppler of the mitral annulus
      • E/e’ > 15 indicates elevated filling pressures/PCWP
      • Specific but not sensitive

    RVSP- Do they have pulmonary hypertension?

    • Estimate RVSP using the TR peak velocity.

    How to interpret

    • TR peak velocity > 2.8 m/s is abnormal
    • RVSP/sPAP > 25 mmHg is abnormal
    • About two-thirds of patients with high LA pressure have pulmonary hypertension
    • If they have pulmonary hypertension, it may be due to elevated LA pressure, though other confounders should be considered, such as COPD

    Putting It All Together

    Normal Diastolic Function

    • e’ > 7 cm/s
    • E/e’ < 15
    • TR velocity < 2.8 m/s

    Grade I Diastolic Dysfunction

    • Medial e’ is abnormal, < 6 cm/s
    • E/e’ is normal
    • No pulmonary hypertension
    • E < A
    • Long deceleration time

    Some patients fall between grade I and grade II. Diastology is often a spectrum.

    Grade II/III Diastolic Dysfunction

    • e’ < 6 cm/s
    • E/e’ > 15
    • TR velocity > 2.8 m/s

    Then use mitral inflow to distinguish:

    • Grade II: E/A < 2
    • Grade III: E/A >> 2

    What If It Is Not Clear?

    Use additional markers of chronic pressure load and LA function.

    Left Atrial Enlargement

    • Normal LA size: no evidence of long-term pressure elevation
    • Enlarged LA: suggests chronic adverse pressure load
      • LA enlargement alone does not tell you current filling pressures.

    Left Atrial Volume Index

    • LAVI > 34 mL/m² is abnormal
    • Not a perfect measure
    • If LAVI is around 50 mL/m², this is almost certainly abnormal

    Left Atrial Strain

    • Measure in the apical 4-chamber view
    • Trace the LA in systole when the LA is largest
    • Software generates the LA strain curve
    • Left atrial strain looks at the contractility/function of the LA.
      • Normal LA strain > 35%
      • Clearly abnormal LA strain < 20%

    Pulmonary Vein Doppler

    Normal flow into the left atrium should be systolic predominant.

    • S > D: likely normal LA pressure
    • D > S: likely abnormal LA pressure

    L Wave

    • Extra wave in early/mid diastole that can indicate increased LV filling pressures 
    LV Diastolic Function Grading & LAP Estimation 1. Reduced e′ velocity: septal ≤ 6 or lateral ≤ 7 or average ≤ 6.5 cm/s 2. Increased E/e′: septal ≥ 15 or lateral ≥ 13 or average ≥ 14 3. Increased TR velocity ≥ 2.8 m/s or PASP ≥ 35 mm Hg All normal Reduced e′ only Increased TR/PASP only or Increased E/e′ only or Any 2 abnormal variables 3 of the above Normal LAP Normal DF E/A ≤ 0.8 E/A > 0.8 Grade 1 Pulmonary Vein S/D ≤ 0.67 or LARS ≤ 18% or LAVI > 34 mL/m² Alternatively IVRT ≤ 70 ms None ≥1 present Increased LAP E/A < 2 E/A ≥ 2 Grade 2 (Mild/Mod ↑ LAP) Grade 3 (Marked ↑ LAP) If symptomatic Diastolic Exercise Echo

    When not to try assessing diastology?

    • Mitral prosthesis or severe mitral annular calcification: immobile structure that won’t move and confound things
    • Mitral stenosis/regurg: LAP probably high but don’t use these measures
    • LVAD/transplant
    • AF
    • LBBB, tachycardia 
    • PH with marked RV dysfunction (with a big RA/RV the shared mitral annulus often reflects RV function)
    LV Relaxation, Filling Pressures, and Doppler Findings
    Finding Normal Grade I Grade II Grade III
    LV relaxation Normal Impaired Impaired Impaired
    LAP Normal Low / normal Elevated Elevated
    Mitral E/A ratio ≥ 0.8 ≤ 0.8 > 0.8 to < 2 > 2
    Average E/e′ ratio < 10 < 10 10–14 > 14
    Peak TR velocity < 2.8 m/s < 2.8 m/s > 2.8 m/s > 2.8 m/s
    LA volume index Normal Normal / ↑ Increased Increased