diastolic dysfunction. normal diastolic function : adequate ventricular filling without abnormal...

Diastolic DysfunctionDiastolic Dysfunction

Normal diastolic function : Adequate ventricular filling without abnormal elevation in diastolic pressures. Ensures normal stroke volume based on Frank Starling mechanism.

Diastole

IVRT EFP AFP

IVRT : Isovolumic relaxation. Energy dependent..

Doppler : Evaluates transmitral velocities resulting from pressure gradients.

EFP : Predominant force = LV elastic recoil (rate LV relaxation) with subsequent vaccum. 80% LVEDV

AFP : Atrial contraction. 20% LVEDV

Variables : 1- Peak E velocity 2- Peak A velocity ( E at A velocity) 3- E/A ratio 4- IVRT (Parallels DT) 5- DT. 6- A duration. ( Compared with AR in PVF tracing) Normally A-AR >0

Pulmonary vein flow

L Atrial relaxation

RV systoleEFP

L Atrial contraction

1- PS1 not seen in 70% cases.2- AF PVS1 lost and PVS2 always smaller than PD3- Peak velocity and duration of PVar increase with increased EDP

Normal Patterns

LV relaxation becomes slower : a) lower initial and peak trasmitral gradient with age resulting in b) Longer IVRT and DT c) Less contribution of early filling d) More of an A component with increased vel. e) E/A ratio close or below one by age 70 d) Increased PVs and decreased PVd with increased PVar velocity.

Abnormal diastolic function Abnormal relaxation pattern

Caused by impaired = slower relaxation. Maintained mean LA and LVEDP.MIT : a) Decreased E velocity + Increased A velocity = E/A ratio < 1 b) Prolonged IVRT and DTPVF : a) Predominant PVs flow with blunting of PVd velocity. b) PVar remains normal or slightly faster. c) A-Pvar >1

Increased A waveIncreased LVEDP base on increased A componentNormal mean LA pressure.Ma < PVar

Transition

Abnormal diastolic function Pseudo-normalization

DT 200 msE/A >1

DT 200 msE/A >1

PVs > PVdMa > PVar

PVs < PVdMa < PVar

Moderate increase in LA atrial pressure superimposed on relaxation abnormality.Clues to pseudonormal pattern : a) Abnormal 2D findings where increased LA pressure is expected. b) LA enlargement without MR/MS. c) Reduction in preload with Valsalva/NTG (LA pressure) can unmask the pseudonormal pattern and bring out the abn. Relaxation = reversal of E/A ratio to <1.

Abnormal diastolic function Restrictive Pattern

Results from marked increase in LAPressure/ Decreased LV compliance/Relaxation abnormality.

MVI1- Increased E velocity2- Short DT (< 160 ms ) & IVRT (< 60 ms)2- E/A ratio > 2. Decreasing with Valsalva

PVF1- Decresed PVs with increased PVd2- Longer/faster Pvar3- Ma << Pvar4- Increased PVar velocity (>0.35 m/s)

Abnormal diastolic function Restrictive Pattern Cont…

Tachycardia can mask PVF reversal due to occurrence of Atrial contraction during forward pulmonary vein flow (mid diast)

LVFP MITRAL INFLOW PULM. VEIN FLOW

Grade Relax Comp. WP LVEDP E/A DT IVRT PVS/PVD PVS % ARV Ma-Pvar Sympt LA Size (msec) (msec) (cm/sec) (msec)

Mild(Abnormal Imp NL NL NL <1 >200 >100 > 1 >50% <35 <20 None NLRelaxation)

Abnormal Imp. NL or NL Inc. <1 >200 >100 >1 >50% >35 and/or >20 None or at NLRelaxation. mildly exerciseLikely elev. Imp.LVEDP) Moderate Imp. Imp. Inc Inc 1-2 150 60 0.5-1 ~50% >35 >20 Rest or Inc. (Pseudo- to to exerciseNormalized 200 100Pattern)

Severe(Restrictive) Imp Imp Very Very >2 <150 <60 <0.5 <50% >35 >20 Rest or L Inc. Inc. excersice











Estimation of LV filling pressures

Similar mitral inflow patterns might reflect completely different processes. General guidelines for estimating filling pressures ( High or normal…)

1- Abn. Relaxation Pattern = Normal filling pressures unless IVRT and DT are normalized or shorter. (<60 / < 160)2- Expected impaired relax. = Elevated pressures (pseudonormal) and E>>A

3- E/A higher and DT shorter = Elevated pressures. than expected.

4- Restrictive filling pattern = Elevated pressures.

5- PVS flow < 40% of all = Elevated pressures (mean LV diast) forward flow. - PVar vel > 0.35 m/s

6- PVar > Ma by 30 msec = LVEDP > 15 mm ( Very reliable indicator)

Not all is black and white in diastolic dysfunction

Severe LVH

Early diastolicRestrictivephysiology

Short PR

Tachycardia

Advanced Amiloidosis

diastolic dysfunction. normal diastolic function : adequate ventricular filling without abnormal...

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