Exam II: Valvular Disease Flashcards
Cardiac output definition
Amount of blood that is ejected from the LV during 1 minute
Average CO
5 L/min
Average CI
2.5 L/min/m2
CO determined by ____ (__-__ bpm), and ___ ___ - the amount of blood ejected from the ____ with each beat (__mL)
HR (70-80 bpm)
Stroke volume
LV
70 mL
Preload - effective tension of the blood on the ____ or the wall tension at the end of ____
Ventricle
Diastole
Preload (passive) - flow from ___ to ____ during ____
Atria to ventricle
Diastole
Preload (active) - volume contributed by the ___ ____
Atrial kick
Frank-Starling Law:
The greater the wall tension, the greater the myocardial contractility until over distention of the myocardium occurs
Preload measurement: ____ or ____
PCWP or PADP
afterload - the ____ ____ that the myocardium needs to overcome to eject the ___ (open the ___ or ____ valves)
wall tension
CO
aortic or pulmonic
afterload is the pressure within the ____ during peak ____
LV
systole
afterload is affected by _____ and _____ compliance - ____ and ____, if only ____ is taken into account, ventricular wall tension is not considered
chamber and vasculature
SVR and MAP
SVR
_____ _____ - the inotropic state that is independent of preload and/or afterload
myocardial contractility
myocardial contractility - rate of ____ changes over time (__/__)
pressure
(dP/dt)
myocardial contractility - velocity of contraction developed by ____ ____
cardiac muscle
myocardial contractility - ____-____ loops
pressure-volume
myocardial contractility - clinically wide range so comparisons between pts is ____ _____, look at changes in _____ over time for a single patient
not reasonable
contractility
Pressure-volume loops: denotes ______ pressure and volumes changes during the ____ ____
intraventricular
cardiac cycle
Pressure-volume loops: simultaneously measure _____ _____ and the resultant _____
chamber pressures
volumes
Cycle
Phase I –
Phase II –
Phase III –
Phase IV –
Cycle
Phase I – diastolic filling
Phase II – isovolumetric contraction
Phase III – systolic ejection
Phase IV – isovolumetric relaxation
Pressure-volume loops - distance between vertical lines represents ____
SV
Pressure-Volume Loop - used to diagram key features of ____ during the ____ ____
LV
cardiac cycle
SV = ____-____
EDV - ESV
ejection fraction = % of ____ ejected with each _____
EDV
contraction
EF = ___/___ x 100
EF = SV/EDV x 100
ex: 80/120 x 100 = 60-70%
minimal increase pressure with ventricular filling reflects ____ character of ____ ventricle
elastic
compliant
cardiac work (pressure x volume) = total area of ____ ____ ____
pressure volume loop
pressure volume loop - greater O2 demand with ____ ____ vs ____ ____
pressure work (afterload) vs volume work (preload)
stroke work of the RV 1/7 that of the LV bc ____ much less than ____
PVR
SVR
A: end of _____
EDV = 110-150 mL
B: beginning of ____ ____
C: end of ____
ESV = 40-80 mL
D: begins ___ ____ – diastolic pressure close to 0
diastole
systolic ejection
systole
LV filling
A to B – all valves ____, no change in volume, but ____ pressure
closed
increased
B to C – stroke volume = ___-___ mL
60-90
C to D – all valves ____, no change in volume, but _____ pressure
closed
decreased
D to A – volume _____ with diastolic filling, pressure ____ only slightly - reflects elastic character of _____ ventricle
increases
increases
compliant
Changes in Preload - theory: If ___ is increased (preload), ejection of blood to same ____; increased SV, EF
EDV
ESV
Changes in Preload - theory: If EDV is decreased (preload), SV _____ as ESV is _____.
decreases
unchanged
To examine the independent effects of preload, assume that ____ ____ and ______ pressure (afterload), and _____ are held constant
aortic systolic
diastolic
inotropy
Increased preload (stretch) means increased ___, increased ___, aortic pressure, increased ____, increased ESV due to decreased velocity
[Changes in Preload – Interdependent with Afterload]
SV
CO
afterload
Decreased preload means decreased ____, decreased ____ ____, decreased ____
[Changes in Preload – Interdependent with Afterload]
SV
aortic pressure
ESV
An increase in preload (end-diastolic volume represented by red loop in figure) leads to an ____ ___ _____ ____ (width of loop) because of the Frank-Starling mechanism.
[Changes in Preload – Interdependent with Afterload]
increase in stroke volume
If aortic pressure is increased, SV, EF are ____ and ESV is _____.
[Changes in Afterload - theory]
smaller
increased
If aortic pressure is decreased, SV, EF are ____ and ESV is _____.
[Changes in Afterload - theory]
increased
decreased
Increased SVR leads to decreased ___, increased ____ – this leads to increased ____ (preload), which increases contraction to offset change in SV (healthy)
[Changes in Afterload – Interdependent with preload]
SV
ESV
EDV
Decreased aortic pressure, SV _____, ESV ______, EDV ______ only slightly
[Changes in Afterload – Interdependent with preload]
increases
decreases
decreases
Two pressure-volume loops representing contractions with ____ ____ fractions and ____ _____, but markedly different mechanical work
identical ejection
stroke volumes
Greater myocardial work due to higher afterload required to maintain ___ and ___
EF
SV
Increased _____ of _____ _____ leads to increased SV, EF and decreased ESV.
[Changes in Inotropy]
velocity of fiber shortening
Decreased pressure at a given LV volume (velocity) leads to decreased ___, ____ and increased ____.
[Changes in Inotropy]
SV
EF
ESV
In PV loop diagrams, increased ______ increases the slope of the end-systolic pressure-volume relationship (ESPVR; red dash line in top panel), which permits the ventricle to generate ____ _____ at a given LV volume. Decreasing _____ has the opposite effects; namely, increased end-systolic volume and decreased stroke volume and ejection fraction (bottom panel of figure).
[Changes in Inotropy]
inotropy
more pressure
inotropy
Increased inotropy leads to increased _____ at a given ___ _____; thus increased SV, EF, and decreased ESV. Then, decreased EDV. Increased CO and MAP.
[Changes in Inotropy - Interdependent with preload]
pressure
LV volume
Decreased ______ leads to increased ESV, decreased SV, EF. Then, increased ____.
[Changes in Inotropy - Interdependent with preload]
inotropy
EDV
Increased inotropy (red loop in figure) increases the ____ and shifts the end-systolic pressure-volume relationship (ESPVR) to the ____, which permits the ventricle to generate more pressure at a given LV volume.
[Changes in Inotropy - Interdependent with preload]
slope
left
Exercise leads to increased _____ _____ (increase in EDV); sympathetic stimulation increases ______ – decreased ESV.
[Changes in Preload, Afterload, Inotropy during Exercise]
venous return
inotropy
with exercise, Combined, small _____ in EDV, large _____ in ESV, _____ SV, EF.
______ BP
[Changes in Preload, Afterload, Inotropy during Exercise]
increase
decrease
increased
increased
Exercise is a good example of how simultaneous changes in preload, afterload and inotropy affect ______ ______ _____ ______ (red loop in figure). During whole body exercise (e.g., running, bicycling) increased venous return to the heart generally causes a small increase in end-diastolic volume.
[Changes in Preload, Afterload, Inotropy during Exercise]
ventricular pressures and volumes
Valvular Disease - Most commonly affected (2)
mitral and aortic
primary valvular dysfunction - valve leaflets or ____ damage to ____ ____ to cause dysfunction
structural
fibrous annulus
Secondary valvular dysfunction – no damage to valve or supporting structure, but dysfunction due to other pathology: ventricular dilation (___), retrograde aortic dissection (___), papillary muscle damage/infarction (___)
MR
AR
MR
left side of heart is ____ pressure side
higher
Stenosis – _____ of orifice (____ outflow)
narrowing
fixed
Stenosis: pressure overload - _____ hypertrophy
concentric
Stenosis: compensation - adding _____ in parallel
sacromeres
Stenosis: _____ wall, decreased ____ of chamber
thicker
radius
Insufficiency or regurgitation – flow _____, instead of ____/____ direction
retrograde
forward/one
Insufficiency or regurgitation: Volume overload – _____ hypertrophy
During ____, __ sources of blood entering
eccentric
diastole
2
Insufficiency or regurgitation: Compensation – adding _____ in series
sacromeres
Insufficiency or regurgitation: _____ chamber, ____ radius
dilated
increased
____ – both stenosis with insufficiency or insufficiency with stenosis (symptoms will be _____ for one over the other)
Mixed
dominant
Sympathetic stimulation – may see _____, ______, ____ _____
anxiety, diaphoresis, resting tachycardia
pre-op eval: severity of disease (3)
- murmur
- acute v. chronic
- compensatory mechanisms (sympathetic stimulation, ventricular hypertrophy - angina due to increased demand even in the absence of CAD)
pre-op eval: myocardial contractility - _______ and symptoms ____, _____, _____
CHF
basilar chest rales, jugular venous distention, S3 sound
pre-op eval: major _____ disease
organ
Murmurs (4) and acronyms to remember them
Mitral Stenosis
M.S.D.A. – Diastolic, Apex/Axilla
Mitral Regurgitation
M.R.S.A. – Systolic, Apex/Axilla
Aortic Stenosis
A.S.S.S. – Systolic, Sternal Rt
Aortic Regurgitation
A.R.D.S. – Diastolic, Sternal Rt
Diagnostic tests: EKG
Notched p wave –
Axis deviation –
Dysrhythmias –
Notched p wave – LA enlargement
Axis deviation – RV or LV hypertrophy
Dysrhythmias – atrial fib
Diagnostic tests: X-ray
looking for cardiomegaly - ____ of internal width of thoracic cage
valvular _____ and _____ in lungs
> 50%
calcifications and markings
Diagnostic tests: ECHO
looking for _____ measurements, valve ____, _____ _____ across a valve, degree of ______ flow
cavity
area
pressure gradients
regurgitant
Mitral Stenosis (MS) - most common cause _____ _____
rheumatic fever
Mitral Stenosis (MS): ____ progression, may become symptomatic after more than __-__ ___ from incidence of rheumatic fever
slow
20-30 years
Mitral Stenosis (MS) occurs more in _____
females
Mitral Stenosis (MS) symptoms (3)
- dyspnea on exertion
- orthopnea
- paroxysmal nocturnal dyspnea r/t increased LA pressures
Mitral Stenosis (MS): ______ of valvular leaflets and subvalvular apparatus, commissural fusion, and ______ of annulus and leaflets
thickening
calcification
