C16: Intro to Diastolic Function Flashcards
define diastole
- phase of the cardiac cycle where the chambers relax and fill w/ blood.
- interval from AV closure to MV closure
define relaxation
relaxation of the ventricles including IVRT and early filling
define compliance
change in volume/change in pressure (Dv/Dp) in the LV during diastole….
e.g. how elastic are the fibers
compliance is inverse to _____?
stiffness
how does the fitness level of the heart effect relaxation time
-more fit= faster to relax
is a thickened ventricle muscle more or less compliant
less
define stiffness
change in pressure/change in volume in the LV during diastole….
are filling pressures high or low w/ a compliant ventricle
low
filling pressures include 2 pressure values?
includes LV end-diastolic press and mean LA press over the diastolic period
what is LVEDP
LV end-diastolic press… reflects the LV press after filling is completed (after the MV doppler A wave)
what is mean LAP
avg press during the LV filling period
define diastolic function
ability of the ventricles to fill to a proper volume at end-diastole to ensure theres enough blood volume ejecting during systole
what does norm diastolic function mean
the LV can fill to a normal volume w/ low filling press in the LV and LA during rest or exercise because the myocardium is compliant
what does diastolic dysfunction mean
the LV can fill to a normal volume but only when the filling press increases to abnormal levels in the LA and LV because the LV is stiff
is there and change in blood volume during IVRT
no
what does a larger press difference b/w the LA and LV indicate about the velocity of blood and filling volumes of the LV
-means there will be increase velocity and increased volume moved from LA to LV
which phase of the heart shortens the most with increased HR
diastasis
on a PW of MV inflow, where would we measure the IVRT
from the closing click of the AV to the opening of the MV
the LA and LV should fill properly under what amount of pressure to be considered normal
< 12 mmHg… >15 is elevated
elevated filling pressures are the consequence of what type of heart dysfunction
diastolic dysfunction
what happens to the stiffness and pressure of the LV when it loses its ability to relax
-both stiffness and pressure increase
what are the 5 factors effecting filling
- compliance
- hypertrophy/infiltrative disease
- extrinsic factors (pericardial stiffness)
- LV muscle remodeling
- Normal changes w/ aging… fibrotic changes in the LV increases the LV stiffness as you age
how will diastolic dysfunction effect the spectral tracing of the MV PW?
- prolonged IVRT and DT
- reduced E wave (due to smaller press gradient b/w LA and LV) and increase A wave
what specifically factors effect early diastolic filling
- preload
- hyper/hypovolemia
- excessive MV regurg (will increase volume of blood moving past the MV)
what specifically factors effect late diastolic filling
- cardiac rhythm (a fib/a flutter)/HR
- atrial contractile function
- increased LVEDP
- ventricular diastolic function
is SOB and symptom of diastolic dysfunction?
yes
are short TDI waves concerning
yes… means the ventricle is stiff
the lateral and medial TDI valves can be as high as _____?
30 cm/s
is a larger E/e prime ratio good or bad?
higher ratio is abnormal and means theres higher filling press
if the LV diastolic dysfunction of abnormal for a period of time the increased filling press will lead to and increase pressure in which other area?
why?
lungs
-due to backwards transmission of pressure
how can an increase in press in the lungs be measured?
via the RVSP method
higher levels of diastolic dysfunction are associate w/ which 2 abnormal values?
TR jet velocity of > 2.7
Or
RVSP > 40mmHg
what 2 changes in the LV and the LA are commonly seen w/ diastolic dysfunction
- LV wall thickening
- LA enlargement
what is one of the biggest causes of diastolic dysfunction and why?
- hypertension…. b/c its a high after load condition that leads to increase LV muscle mass and thickness which makes it less compliant… which leads to increased filling press
- will also increase the size of the LA
if the E/e prime value is 12, what can we assume?
there is some level of diastolic dysfunction but the LV is still filling under normal pressures.
what value E/e prime value is considered elevated
> /= 15
what is a normal E/e prime value?
= 8
What might lead to a small E wave and a large A wave
A stiff ventricle… the LV cant relax as quickly which decreases the pressure gradient b/w the LV and LA…. less pressure means slower velocity and less volume entering the ventricle
What does it mean if you have a small e prime and a large E wave?
How will this effect E/e prime ratio?
It means that the ventricle is stiff BUT the LV is still filling to adequate volumes due to a increase in L heart pressure
E/e prime ratio will be larger (< 8)
