Diastolic Dysfunction Flashcards
diastolic suction
A ventricular negative pressure when the ventricle is
allowed to relax completely in the absence of filling. It has not been
extensively studied in the human heart in vivo.
Loading factors
By plotting ventricular load as tension time index
against stroke volume, one obtains a valid pump function curve for one beat which is insensitive to changes in heart rate but remains sensitive to changes in end-diastolic volume and contractility
phases of diastolic function
- IVRT: LV relaxes after AV closes
- rapid filling: E wave
- atrial contraction: A wave
what is normal diastolic function
-the ability of the left ventricle to fill in a competent fashion
• This implies that the filling of the LV will not cause a significant increase in LV pressure
what is diastolic dysfunction
- impaired LV relaxation and increased LV chamber stiffness, which increase cardiac filling pressures
- LV pressure will increase rapidly
- ecreased compliance, decreased relaxation or both
assessing for diastolic function
- mitral inflow
- tissue doppler
- color m mode
- pulmonary inflow
- left atrial volume index
what 2 places do you perform tissue doppler
mitral annulus on the lateral and septal walls
what measurements do you get at the PW of the mitral inflow
- E and A filling peaks
- deceleration time
- IVRT
mitral inflow PW normal findings E & A
biphasic, separate E & A peaks;
E > A; E/A ratio between 0.8 and 2.0
E/A > 1 for children and adults < age 50 E increases and A decreases with age
normal deceleration time
160-240 msec
increases with age
normal IVRT
60-100 msec
reflects the rate of the relaxation of the myocardium
values age sensitive
IVRT is longer in patients with…
imparied relaxation
ivrt is shorter in patients with
restrictive filling
what is IVRT
the time interval between aortic valve closure and mitral valve opening
IVRT is also prolonged in patients with…
CAD, advanced age, hypertrophy due to relaxation abnormalities
pitfalls of measuring diastolic function
- cardiac arrhythmias: changes inflow patterns
- tachycardia: fuses E and A together
- A fib : produces no A wave
normal TD medial E prime velocity
11.5 cm/s
normal lateral E prime velocity
13.3 cm/s
TDI velocities less than 8 cm/s indicates what?
diastolic dysfunction and relaxation
what is the annular velocity associated with restrictive filling
5 cm/s
this indicates normal LV diastolic pressure
E/E’ < 8
this value indicates increased LV pressure
E/E’ ratio > 15
TDI is not reliable in patients with…
basel ischemia, mitral valve disease, constrictive pericarditis
color m mode velocity represents
the velocity of blood flow from the mitral leaflets to the apex of the ventricle in early diastole
greater than 50 cm/s is normal
how to obtain color m mode
- In AP4 decrease the depth until the sector only shows the full mitral annulus and the LV only
- Place a color box over the entire LV and MV. Shift the color baseline upward until the top number is about 45 cm/s.
- Place the cursor through the middle of LV apex and select M-mode
- Show trace of M-mode with color and measure Vp with a slope
normal pulmonary inflow over 50 yrs old
higher systolic flow, lower diastolic flow
normal pulmonary inflow under age 40
higher diastolic velocity
LA volume index greater than 34 predicts
death, heart failure, A fib, and stroke
left atrial volume is measured in …
end systole
AP4 and AP2
stage 1 diastolic dysfunction
early diastolic dysfunction, mild diastolic dysfunction, impaired relaxation, abnormal relaxation
diastolic dysfunction stage 2
pseudo normal moderate
stage 3 diastolic dysfunction
restrictive filling
severe
Stage I: Early Diastolic Dysfunction
most common filling abnormality associated with coronary artery disease and hypertension
associated with an increase in LVEDP. During the rapid filling phase of diastole, the increase in LV filling pressures results in a decrease in the amount of blood moving from LA to LV.
reduced E wave, increased DT and a higher
A wave.
Stage I: Early Diastolic Dysfunction is associated with
Associated with several diseases, such as coronary artery disease
(CAD), cardiomyopathy, hypertension, left ventricular hypertrophy (LVH) and pulmonary hypertension
Stage I: Early Diastolic Dysfunction mitral inflow
- Decreased E velocity
- Increased A velocity
- Increased DT
- Increased IVRT
Stage I: Early Diastolic Dysfunction tissue doppler
E’ is reduced (< 8) because of abnormal
compliance and relaxation
• E/E’ ratio is < 15, no significant increase
Stage I: Early Diastolic Dysfunction pulmonary veins
normal ratio > 1
Stage II: Pseudonormal
mitral inflow
PW Doppler pattern seems normal. An increase
in LA pressure may mask the relaxation abnormality and normalize the trans-mitral flow
Stage II: Pseudonormal
tissue doppler
a lower E’ than A’
• E’ is decreased because of decreased LV
compliance and abnormal relaxation
• E/E’ ratio > 15
Stage II: Pseudonormal
pulmonary vein inflow
will have little or no systolic flow (S-wave) and high diastolic flow (D-wave)
• S/D ratio < 1
how to identify pseudonormal patterns
- valsalva maneuver
2. TDI: an E/E’ greater than 12 shows increased LA pressure
stage 3: restrictive
- early pressure gradient is high due to the high LA pressure resulting in increased E velocity. The pressure gradient between the LA and LV equalizes quickly, due to the rapid rise in LV diastolic pressure, resulting in decreased DT.
- A velocity is low, resulting in an increased E/A ratio
- In the case of increased LA pressure, the S/D ratio will be reversed—or there will be no systolic flow at all.
stage 3 restrictive MV inflow
- Very high E velocity
- Much lower A velocity
- Increased E/A ratio: > 2
- Decreased DT: < 140 msec
- Decreased IVRT
stage 3 restrictive tissue doppler
• Significantly decreased E’ velocity because LV
cannot relax normally
• E/E’ ratio is > 15
stage 3 restrictive pulmonary vein inflow
• Tall D wave
• Significant reduction in S/D ratio (almost no S-
wave)
ventricular relaxation and dP/dt
- occurs when the LV pressure declines during IVRT after aortic valve closure and is represented by the rate and duration of the decrease in LV pressure after systolic contraction.
- assessed by measuring the early slope of the CW Doppler of the mitral regurgitation jet. This indirect measurement is the dP/dt.
major determinant os LV filling are
ventricular relaxation and passive diastolic properties
normal dP/dt values
greater than 1200 mmHg
as LV compliance decreases…
increase in filling pressures is required to maintain normal cardiac filling, volume and output.
seen with LV hypertrophy, ischemia and increasing LV volume
LVEDP greater than 16 mmHg is considered
increased filling pressures
Systolic Function Severe dysfunction
dP/dt < 800 and t > 40 msec
normal systolic function
dP/dt > 1200 mmHg and t < 27 msec