The Sonographer Attachment Programme At USA Report : Mayo Clinic: Sonographer Experience =Diastolic Function=

Mayo Clinic Left Ventricle Diastolic Function Working Group

Left Ventricle Diastolic Function : Background

Mitral inflow and pulmonary venous patterns have been validated in many patients sets and show a consistent relationships to left ventricular filling pressures in patients with left ventricular systolic dysfunction. Prognostic information has also been identified in the mitral inflow patter.

Left atrial size has been validated with left ventricular filling pressures and specifically, a normal left atrial size is associated with normal atrial loading conditions. Increased left atrial size can be viewed as  an indicator of subacute to chronic left atrial loading conditions but not necessarily the current status of LV filling (i.e glycosylated hemoglobin in diabetes).

Tissue Doppler variables have been validated in a few sets of patients with cardiac disease with both normal and decreased systolic function. The ratio E/e’ is a method to normalize the speed of blood flow against the speed of myocardial relaxation.

All of Doppler variables reflect beat-to-beat interaction of pressure gradient and operating compliance. The information from LA size and Doppler is complementar.

For preserved systolic function the filling patterns (systolic/diastolic predominance) are not as predictive as accurate measurement of E/e’, A wave duration, or response to preload manipulation.

Diastolic dysfunction can occur with and without elevated filling pressures.

Systolic dysfunction is generally associated with diastolic dysfunction.

The diastolic grading system described Appleton/Hatle and simplified by Nishimura/Tajik is the most recognized and generally accepted system to date.

The best screening test are those that can easily be applied to the largest proportion of patients and provide discriminatory information. LV systolic function, left atrial size, mitral inflow, and tissue Doppler are easily obtained in >95% of patients. Pulmonary venous pattern is readily available but often provides confirmatory evidence to the mitral inflow pattern. A wave durations are difficult to accurately obtain and thus are not part of the initial screen. Likewise, preload manipulation is difficult and often unnecessary.

Who Needs More Comprehensive Assessment Of Diastolic Function

·    Patient referred specifically for diastolic function assessment.

·    Patient referred with chief complaint of dyspnea.

·    Patients with new finding of elevated right heart pressure.

·    Patient with marked abnormalities on screening assessment.

What Should Be Done For A Comprehensive Diastolic Assessment

In addition to the screen listed above

Pulmonary venous pattern and careful assessment of A wave. Make sure the signal is believable and duration is truly measurable (i.e. sample volume well within the pulmonary vein.

Mitral A wave duration at the mitral annulus (to compare with pulmonary vein a wave duration).

Mitral inflow with preload manipulation. This generally to help differentiate normal from pseudonormal (or reversible restrictive from irreversible) and is best accomplished with Valsalva maneuver. Sublingual nitroglycerine can also be used. In some circumstances, passive leg raise can be used to augment filling pressure and demonstrate a lack of ability to compensate for increased preload.

Consider Color M-Mode.

Screening Diastole In Patients With Normal LV Systolic Function

If LA size is normal (volume<32mL/m2), the patient is unlikely to have altered atrial loading condition. Abnormal TDI ratios in this set should be viewed with skepticism. If the finding is strikingly abnormal, the confirmatory evidence from Valsalva maneuver and pulmonary vein flow should be sought prior to reporting abnormal diastolic function.

If LA is increased (LA volume index≥32cc/m2), the patient has probably had some subacute or chronic exposure to increased filling pressures. The Doppler data can give insight to the current load. A markedly elevated TDI ratio (>15) is usually associated with increased LA pressure, while a ratio < 8 is generally associated with normal current LA pressure. If the patient falls in the intermediate zone and does not have dyspnea or specific referral for diastolic assessment, then “No definitive evidence of increased filling pressures” or “No overt diastolic dysfunction” can be reported.

For patients in need of more comprehensive diastolic assessment with normal EF, A wave durations can give insight to LVEDP. A pulmonary vein a wave duration that is 30 ms longer than the mitral a wave is a highly specific finding for increased EDP. Likewise, an absolute decrease in the E/A ratio of 0.5 during the Valsalva maneuver is specific for detecting increased LA pressure. Remember to account for the E @ A velocity. While a lengthening of deceleration time can be a clue to this same pathophysiology, the fusion of the mitral inflow signal that is often seen during the maneuver makes this measurement less reliable.

Screening Diastole In Patients With LV Systolic Function

E/A ratio <0.75 generally has low filling pressure can be reported as Grade I diastolic dysfunction. If E/e’ is elevated, then grade Ia diastolic dysfunction (abnormal relaxation) with evidence of elevated filling pressure can be reported. Confirmation of the latter can be sought in the relative A wave duration.

E/A eation more than 1.5 generally is restrictive and associated with increased filling pressure. Valsalva maneuver can be performed to differentiate reversible (Grade III) from irreversible (Grade IV) filling pattern.

Patients not meeting the above criteria are likely pseudonormal (Grade II) and have modest elevations of filling pressures. Tissue Doppler and pulmonary vein analysis can be used to augment the confidence of the interpretation.

Left Ventricle Diastolic Function : Caveats And Critical Concerns

There is no single number/parameter or algorhythm that can replace careful thought by the interpreting physician/team.

As interpreters, we can frequently discard data that do not fit the clinical picture (M-Mode measurement,PISA measurement etc.) and should also do so for the parameters of diastolic function (don’t assume that LA volume is correct-look at the image, don’t rely on E/e’ if it is discordant with other data.

There are patient insurability issues for reports of “diastolic dysfunction”, therefore we should be careful not to label a patient when it will not affect the clinical management.

While a suggested reporting format can be useful, forcing round pegs into square holes should be avoided.

E/e’ is not validated in states of decreased viscosity (i.e. significant anemia) because blood flow velocities will be faster in the absence of increased pressure.

Patients with significant MR will have elevated LA pressure. The E/e’ ratio can be elevated in these individuals and does not necessarily reflect diastolic dysfunction, but rather increased LA pressure from the MR. Likewise evidence of increased LVEDP in the presence of AR may indicate significant AR and not necessarily concomitant myocardial dysfunction. 

 If the E/e’ data does not fit, try using the lateral annulus for the e’ measurement.

Basic Tenets

·    Diastolic Function analysis is important.

·    Diastology should be screened on each standard echo.

·    More detailed diastolic function assessment is necessary in a subset of patients.

·    Standard report format will improve communication with echo consumers.

·    Assessment should be based on peer reviewed data.

What Parameter Constitute Diastology Screen Panel

·    LV Systolic Function.

·    LA Size Assessment (Preferably LA Volume).

·    Mitral Inflow Pattern At Rest.

·    Mitral Annulus Tissue Doppler.

Diastolic Function Report

Standardized Report Format

Normal Diastolic Function

Grade I Diastolic Dysfunction With Normal Filling Pressure (Alternative In Report : Grade I Diastolic Dysfunction Without Evidence Of Increase Filling Pressure).

Grade Ia Diastolic Dysfunction With Mildly Increased Filling Pressures.

Grade II Diastolic Dysfunction With Moderate Increased Filling Pressures.

Grade III Diastolic Dysfunction (Reversible Restrictive Pattern) Consistent  With Severely Elevated Filling Pressures.

Grade IV Diastolic Dysfunction (Irreversible Restrictive Pattern) Consistent  With Severe Diastolic Dysfunction And Severe Elevated Filling Pressures

Indeterminate Diastolic Function

Comprehensive Interpretations Criteria Of Diastolic Function

>> Normal Diastolic Function And Filling Pressures

Must satisfy all criteria:

·    E/A > 0.75.

·    E/e’ < 15.

·    Normal LA Volume (<32 mL/m2).

·    Normal EF and no other significant abnormality.

>> Grade I Diastolic Dysfunction (Abnormal Relaxation Pattern)

·    E/A ≤ 0.75 (if E at A < 0.2 m/sec).

·    E/e’ < 15.

>> Grade Ia Diastolic Dysfunction With Evidence Of Increased Filling Pressures

·    Patients with abnormal relaxation pattern and other evidence of abnormal filling pressure.

·    Do not meet criteria of Grade I or Grade II.

>> Grade II Diastolic Dysfunction With Moderate Increased Filling Pressures

·    E/A = 0.75-1.50 and Deceleration Time > 160 ms.

·    LV dysfunction or at least two of following:

-          LA enlargement by M-Mode or LA Volume (>32 mL/m2).

-          E/e’ > 12.

-          Change in E/A with Valsalva Maneuver of ≥ 0.5.

-          Pulmonary Vein S/D ≤ 0.5.

-          Pulmonary Vein atrial reversal velocity ≥ 0.35 m/sec.

-          Delta duration ≥ 30 ms.

>> Grade III Diastolic Dysfunction (Reversible Restrictive Pattern) Consistent  With Severe Elevated Filling Pressures

·    E/A = > 1.50 and Deceleration Time < 160 ms.

·    Change in E/A with Valsalva Maneuver of ≥ 0.5.

>> Grade IV Diastolic Dysfunction (Irreversible Restrictive Pattern) Consistent  With Severe Diastolic Dysfunction And Severe Elevated Filling Pressures

·    E/A = > 1.50 and Deceleration Time < 160 ms.

·    Change in E/A with Valsalva Maneuver of < 0.5.

>> Indeterminate Diastolic Function

Diastolic assessment clinically indicated and attempted but:

·    Data inconsistent.

·    Unable to obtain enough parameters.

·    Atrial fibrillation without consistent Deceleration Time < 140 ms.

·    Other abnormal rhythm, short PR, fusion of E and A.

How To Obtain Mitral Annulus TDI Signals

Minimize

·    Filter

·    Sample Volume

·    Gain

·    Scale Range

If there is a significant septal wall motion abnormality, then use the lateral annulus.

Mayo Clinic Diastolic Function Reporting

Mayo Clinic Diastolic Function Reporting : Standard Reporting Format

Normal Diastolic Function.

Grade I Diastolic Dysfunction With Normal Filling Pressure (Alternative In Report : Grade I Diastolic Dysfunction Without Evidence Of Increase Filling Pressure).

Grade Ia Diastolic Dysfunction With Mildly Increased Filling Pressures.

Grade II Diastolic Dysfunction With Moderate Increased Filling Pressures.

Grade III Diastolic Dysfunction (Reversible Restrictive Pattern) Consistent  With Severely Elevated Filling Pressures.

Grade IV Diastolic Dysfunction (Irreversible Restrictive Pattern) Consistent  With Severe Diastolic Dysfunction And Severe Elevated Filling Pressures.

Indeterminate Diastolic Function.

Mayo Clinic Diastolic Function Reporting : Diastolic Examination in the Echo Lab

>> Diastolic Screen Exam

·    LV Size And Function.

·    LA Volume.

·    Mitral Inflow (E Velocity, A Velocity, Deceleration Time).

·    TDI e’, E/e’.

>> Comprehensive Diastolic Examination

·    Pulmonary Vein (PVs, PVd, PVa, PV a duration).

·    Mitral A duration.

·    Mitral Inflow (E Velocity, A Velocity, Deceleration Time) with Valsalva Maneuver.

·    Consider color M-Mode.

Mayo Clinic Diastolic Function Reporting : Which Exam Should Be Done

The Diastolic Screening Exam should be performed on all adult TTE studies.

The Comprehensive Diastolic Examination should be performed.

Referral for dyspnea, unexplained Pulmonary Hypertension (PHT) or Diastolic Screening.

Indeterminate Diastolic Screening Exam.

Grade II Diastolic Screening Exam.

Mayo Clinic Diastolic Function Reporting : Sonographer Role

PVs, A duration and Valsalva Maneuver are not necessary part of standard examination.

If the Diastolic Screen is clearly abnormal, then do the comprehensive measurement.

If you calculate that the screen is indeterminate or more than grade I, consider obtaining other parameters while waiting for review.

Mayo Clinic Diastolic Function Reporting : Consultant Role

  

If good measurement are made, a significant proportion of grades may be assigned based on Screening Examination only.

The Diastolic Screening Examination only certain will be incorporated in to computer system to suggest a diastolic grade, which can be accepted or rejected for each study.

The Diastolic Screening Interpretation Criteria and Comprehensive Diastolic Examination Interpretation Criteria will be posted in review areas.