1. Assessment of Diastolic function by echo
Dr Shreetal Rajan Nair

2. Diastolic function Physiology Epidemiology of diastolic dysfunction
Diastolic heart failure – definitions
Etiology of diastolic dysfunction
Echo assessment of diastolic function
- present guidelines
- newer concepts

3. Diastolic dysfunction
defined as an inability of the left ventricle (LV) to attain a normal end-diastolic volume without an inappropriate increase in LV end-diastolic pressure (LVEDP)

4. Epidemiology – Heart Failure with Preserved Ejection Fraction (HF-PEF)
Accounts for 50% of cases of heart failure
older , more in females and more incidence in obese
Associated with hypertension,T2DM,dyslipidemia, and atrial fibrillation (AF).
Patients with HF-PEF have
a worse prognosis than those with Heart Failure with Reduced Ejection Fraction (HF-REF)

5. HF- PEF - DIAGNOSIS 1. Symptoms typical of HF 2. Signs typical of HF
3. Normal or only mildly reduced LVEF and LV not dilated
4. Relevant structural heart disease (LV hypertrophy/LA enlargement) and/or diastolic dysfunction
ESC 2012

6. ACCF/AHA 2013
a) clinical signs or symptoms of HF b) evidence of preserved or normal LVEF c) evidence of abnormal LV diastolic dysfunction that can be determined by Doppler echocardiography or cardiac catheterization

7. Physiology The ventricle has two alternating functions:
systolic ejection
diastolic filling
Diastole can be divided into four phases:  
▪   Isovolumic relaxation   ▪   The early rapid diastolic filling phase   ▪   Diastasis   ▪   Late diastolic filling due to atrial contraction
Left atrium functions as a RESERVOIR during systole, CONDUIT during early diastole and PUMP during late diastole

9. Atrial Pressures and Filling Curves

10. RA filling Right atrial filling is characterized by
 ▪   Small reversal of flow following atrial contraction (a wave)   ▪   Systolic phase : when blood flows from the superior and inferior vena cava into the atrium   ▪   Small reversal of flow at end-systole (v wave)   ▪   Diastolic filling phase when the atrium serves as a conduit for flow from the systemic venous return to the RV

11. LA fiiling
LA filling from the pulmonary veins also is characterized by :
 ▪   Small reversal of flow following atrial contraction (a wave)   ▪   Systolic filling phase   ▪   Blunting of flow or brief reversal at end-systole (v wave)   ▪   Diastolic filling phase

12. Determinants of diastolic function
Ventricular relaxation and compliance
LA volume and function
Heart rate
Pericardium
Derangement of any of the above will lead to abnormal filling pressures and diastolic dysfunction

13. Factors affecting diastolic filling
Early diastolic filling affected by
preload
transmitral volume flow rate
atrial pressure
Late diastolic filling is affected by:  
Cardiac rhythm
Atrial contractile function
Ventricular end-diastolic pressure  

15. Etiology of diastolic dysfunction

16. Classification: diastolic dysfunction
Grade 1 (mild dysfunction) : impaired relaxation with normal filling pressure Grade 1a : impaired relaxation with increased filling pressure Grade 2 (moderate dysfunction): pseudonormalized mitral inflow pattern Grade 3 (severe reversible dysfunction): reversible restrictive (high filling pressure) Grade 4 (severe irreversible dysfunction): irreversible restrictive (high filling pressure)

18. Echo assessment of diastolic function
Echocardiographic assessment of diastolic filling pressure has been aptly described as “ noninvasive Swan-Ganz catheter ” 2D
Doppler – PW,CW and TDI
M mode
Newer modalities

19. Diastolic function assessment
Anatomic correlates Functional correlates

20. 2D LV mass and dimensions
LV hypertrophy is the commonest cause of diastolic dysfunction
Relative wall thickness :
LA volume and LA volume index

21. LA volume and LA volume index
LA volume index >34ml/m2 - independent predictor of death, heart failure, atrial fibrillation and ischemic stroke
Limitations:
dilated left atria – bradycardia,anemia and other high-output states, atrial flutter or fibrillation and significant mitral valve disease

22. Ventricular Relaxation
IVRT
the maximum rate of pressure decline(–dP/dt)
the time constant of relaxation (tau or τ)

24. Tau and ventricular relaxation

25. Tau and Weiss formula
t corresponds to the time it takes for LVP to fall to 1/e (36%) of its initial value.
The formula also indicates that LVP fall, and therefore relaxation, will be 97% complete 3.5*t after dP/dt
Diastolic dysfunction is present when tau is >48 ms
Pt=(P0-P‘)e-t/t+P‘
where Pt is LVP at time t;
P0 is LVP at dP/dt min (time 0); P‘ is the asymptotic pressure, to which relaxation would lead if completed without LV filling.
P‘ is negative in normal ventricles, which means that the non-filling ventricle develops diastolic suction.

26. Ventricular Compliance and stiffness
Compliance is the ratio of change in volume to change in pressure (dV/dP).
Stiffness is the inverse of compliance: the ratio of change in pressure to change in volume (dP/dV)

27. SURROGATE MESUREMENTS of ventricular stiffness
DT of mitral velocity
Stiffness
[in millimeters of mercury per ml] is calculated as K = [70ms/(DT- 20ms)
A wave transit time

29. The slope (Kc) of this line is the chamber stiffness constant and can be used to quantify chamber stiffness.

30. Acquisition of mitral inflow
apical 4 chamber, PW
1 mm – 3mm sample volume between mitral valve tips
initially obtained at sweep speeds of 25 to 50 mm/s for the evaluation of respiratory variation of flow velocities
If variation is not present, the sweep speed is increased to 100 mm/s, at end-expiration, averaged over 3 consecutive cardiac cycles

33. Mitral inflow Primary measurements the peak early filling (E-wave)
late diastolic filling (A-wave) velocities
the E/A ratio
deceleration time (DT) of early filling velocity
the IVRT
derived by placing the cursor of CW Doppler in the LV outflow tract to simultaneously display the end of aortic ejection and the onset of mitral inflow

34. Mitral inflow Secondary measurements
mitral A-wave duration (obtained at the level of the mitral annulus) diastolic filling time
the A-wave velocity-time integral and the total mitral inflow velocity-time integral (and thus the atrial filling fraction)
Mid diastolic flow is an important signal to recognize. Low velocities can occur in normal subjects but when increased (>20 cm/s)- represent markedly delayed LV relaxation and elevated filling pressures

35. The mitral L wave
distinct forward flow velocity after the E wave with a peak velocity >20cm/s
Marker of advanced diastolic dysfunction
Delayed and prolonged LV relaxation
Increased LA pressure
Effect of valsalva and leg elevation
More frequently seen in AF patients
Eur J Echocardiography (2006) 7, 16-21; Ha et al
Circ J 2007; 71: 1244–1249; Nakai et al

36. The mitral L wave

37. IVRT
time interval between aortic valve closure and mitral valve opening
normal IVRT is approximately 80 to 100 ms
Impaired relaxation associated with prolonged IVRT
Decreased compliance and elevated filling pressures associated with shortened IVRT
Useful in determining the severity of diastolic dysfunction particularly in serial studies of patients on medical therapy or with disease progression

38. IVRT
CW Doppler in the LV outflow tract to simultaneously display the end of aortic ejection and the onset of mitral inflow.

39. Limitations of mitral inflow measurement
sinus tachycardia
conduction system disease
Arrhythmias
Sinus tachycardia and first-degree AV block can result in partial or complete fusion of the mitral E and A waves (mitral DT cannot be measurable; IVRT can be measured

40. Limitations of mitral inflow measurement
In atrial flutter
Unable to measure E velocity, E/A ratio or DT
In AV blocks
multiple atrial filling waves are seen, with diastolic mitral regurgitation (MR) interspersed between non conducted atrial beats
PA pressures calculated from Doppler TR and PR

41. Valsalva maneuver Clinical applications
A pseudo normal mitral inflow pattern is caused by a mild to moderate increase in LA pressure in the setting of delayed myocardial relaxation
Because the Valsalva maneuver decreases preload during the strain phase, pseudo normal mitral inflow changes to a pattern of impaired relaxation
In cardiac patients, a decrease of >/= 50% in the E/A ratio is highly specific for increased LV filling pressures, but a smaller magnitude of change does not always indicate normal diastolic function.

42. QUANTITATIVE ANALYSIS
1 . MAXIMUM VELOCITIES
2 . VELOCITY TIME INTEGRALS
3 . TIME INTERVALS
4 . ACCELERATION AND DECELERATION

44. TDI - acquisition PW apical view
The sample volume should be positioned at or 1 cm within the septal and lateral insertion sites of the mitral leaflets.
sweep speed of 50 to 100 mm/s at end-expiration ; average of >/= 3 consecutive cardiac cycles.
For the assessment of global LV diastolic function, it is recommended to acquire and measure tissue Doppler signals at least at the septal and lateral sides of the mitral annulus and their average.
In patients with cardiac disease, e’ can be used to correct for the effect of LV relaxation on mitral E velocity, and the E/e’ ratio can be applied for the prediction of LV filling pressures.
The E/e’ ratio is not accurate as an index of filling pressures in normal subjects or in patients with heavy annular calcification, mitral valve disease and constrictive pericarditis

45. TDI Early diastolic filling velocity (e′)
Filling velocity after atrial contraction (A′)
Ratio of early to atrial diastolic myocardial velocity (e′/A′)
Ratio of transmitral blood flow velocity to tissue Doppler velocity (E/e′)

47. Medial vs lateral annular velocities
use the average (septal and lateral) e´ velocity in the presence of regional dysfunction
septal E/e´ ratio
<8 is usually associated with normal LV filling pressures
a ratio >15 is associated with increased filling pressures
between 8 and 15, other echocardiographic indices should
be used.
In normal EFs, lateral tissue Doppler signals(E/e ánd e´/a´) have the best correlations with LV filling pressures and invasive indices of LV stiffness.

48. TE-e´is particularly useful in situations in which the peak e´velocity has its limitations
the E/e´ ratio is 8 to 15.
an IVRT/TE-e´ratio ,2 has reasonable accuracy in identifying patients with increased LV filling pressures

49. PCWP and E/e’

50. PCWP and E/e’

51. PCWP and E/e’
pulmonary capillary wedge pressure usually is >20 mm Hg when E/e’ is >15 (e’from the medial annulus) or >12 (e’ from lateral annulus)

52. E/e’ ratio
E/e’ is highly predictive of adverse events in acute myocardial infarction,hypertensive heart disease, severe secondary MR, end-stage renal disease, atrial fibrillation and cardiomyopathy
The E/e’ ratio is among the most reproducible echocardiographic parameters to estimate PCWP and is the preferred prognostic parameter in many cardiac conditions.

53. Pulmonary venous flow - acquisition
Apical 4 chamber PW
Sample volume 2mm-3mm > 0.5 cm into the pulmonary vein
Wall filter settings must be low enough to display the onset and cessation of the atrial reversal (Ar) velocity waveform
sweep speed of 50 to 100 mm/s at end expiration; average of >/=3 consecutive cardiac cycles.

55. PULMONARY VENOUS WAVE FORM
peak systolic (S) velocity, peak anterograde diastolic (D) velocity , the S/D ratio
systolic filling fraction (Stime-velocity integral/[Stime-velocity integral?
D time-velocity integral]) and the peak Ar velocity in late diastole.
Other measurements are the duration of the Ar velocity, the time difference between it and mitral A-wave duration (Ar ? A)
and D velocity DT.
There are two systolic velocities (S1 and S2

56. Acquisition – color M mode flow propagation velocity
apical 4-chamber view
color flow imaging .
M-mode scan line is placed through the center of the LV inflow blood column from the mitral valve to the apex.
color flow baseline is shifted to lower the Nyquist limit so that the central highest velocity jet is blue.
Flow propagation velocity (Vp) is measured as the slope of the first aliasing velocity during early filling, measured from the mitral valve plane to 4 cm distally into the LV cavity.
Alternatively, the slope of the transition from no color to color is measured.
Vp >50 cm/s is considered normal

59. Diastolic stress test supine bicycle or treadmill protocol. E ; e’
TR jet assessed before and after exercise
Diastolic heart failure : E/e’ ratio increases and pulmonary systolic pressure increases
In normal heart the ratio is maintained
Role of dobutamine ???

60. Estimation of LV filling in special populations
Atrial fibrillation : measurements of average of 10 cycles
Sinus tachycardia: E – A fusion occurs
Restrictive cardiomyopathy
Hypertrophic cardiomyopathy - Ar - A duration (>30 ms) used to predict LVEDP
Pulmonary hypertension

61. Predictors of raised LVEDP

62. PCWP and various parameters
Mean PCWP= 17+ (5XE/A)- (0.11 X IVRT)
E/Vp > 2.5 predicts PCWP > 15 mm Hg
T (E-e’) delayed in impaired relaxation
IVRT/ T (E-e’) < 2 predicts PCWP > 15 mm Hg
Ar velocity – mitral A >/= 30 ms – marker of raised PCWP

63. Recent indices of diastolic function

64. Summary- diastolic parameters

68. Thank you