Valvular heart disease Flashcards
What are the four heart sounds?
S1
S2
S3
S4
What is the S1 heart sound?
closure of the mitral and tricuspid valve “lub”
What is the S2 heart sound?
closure of the aortic and pulmonic valve “dub”
What is the S3 heart sound?
suggests congestive heart failure
What is the S4 heart sound?
suggests poor ventricular compliance
Where should you listen for the aortic valve sounds?
right of sternal border at 2nd ICS
Where should you listen for the pulmonic valve sounds?
left of sternal border at 2nd ICS
Where should you listen for the mitral valve sounds?
left midclavicular line at 5th ICS
Where should you listen for the tricuspid valve sounds?
left of sternal border at 4th ICS
Which valvular diseases are associated with eccentric hypertrophy? (select 2)
a. mitral stenosis
b. mitral regurgitation
c. aortic stenosis
d. aortic regurgitation
b. mitral regurgitation
d. aortic regurgitation
The ____________________________ open to let blood flow from the atria to the ventricles
atrioventricular valves (mitral and tricuspid)
The ___________ open to let blood flow from the ventricles to the aorta and pulmonary artery respectively
semilunar valves (aortic and pulmonary)
Valvular stenosis is a ____________ to forward flow during systole
fixed obstruction
Stenosis results in
pressure overload–> concentric hypertrophy
Concentric hypertrophy means that the
sarcomeres are added in parallel
Valvular regurgitation occurs when the
valve is incompetent
Flow re-enters the chamber through the incompetent valve during
diastole
Regurgitation results in
volume overload–> eccentric hypertrophy
Eccentric hypertrophy means that the
sarcomeres are added in series
Which valves have chordae tendineae?
atrioventricular valves (mitral & tricuspid)
Following aortic valve replacement for aortic stenosis, the left ventricular end-systolic volume will be:
a. increased due to afterload reduction
b. increased due to decreased transvalvular gradient
c. decreased due to a reduction in impedance to ventricular ejection
d. unchanged
c. decreased due to a reduction in impedance to ventricular ejection
The smaller the aortic valve orifice, the more
pressure the ventricle must produce to eject its stroke volume
Normal aortic valve orifice size is
2.5-2.5 cm2
Severe aortic stenosis is
<0.8 cm2
Etiologies of aortic stenosis include
a bicuspid aortic valve (most common)
rheumatic fever
infective endocarditis
Compensatory mechanisms for aortic stenosis include
increased thickness of the LV wall
decreased compliance
smaller chamber radius
The classic presentation of aortic stenosis includes
syncope
angina
dyspnea
___________ should be avoided in the patient with severe aortic stenosis due to risk of CV collapse
spinal anesthesia
In the patient with severe aortic stenosis, chest compressions during CPR are often
ineffective due to the high transvalvular pressure gradient required
The arterial waveform of aortic stenosis may show
pulsus tardus and pulsus parvus
Anesthetic goals for aortic stenosis for HR, heart rhythm, preload, afterload, contractility, and PVR.
Full, slow, constricted
heart rate–> avoid tachycardia
heart rhythm–> NSR (maintain atrial kick)
preload–> increase
afterload–> maintain or increase
contractility–> maintain
pulmonary vascular resistance–> normal
A mean transvalvular pressure gradient (LV to aorta) of ________________- is also diagnostic for severe AS
> 40 mmHg
______________ occurs in up to 90% of patients with severe aortic stenosis.
Acquired von Willebrand disease–> b/c the von Willebrand molecule is damaged when it passes through the stenotic valve
What should be given if LV dysfunction occurs in the aortic stenosis patient?
inotropes to maintain contractility
Aortic insufficiency leads to
volume overload & eccentric hypertrophy
Aortic insufficiency can be an ______________ or ___________ problem
acute or chronic
The arterial waveform of aortic insufficiency shows
an increased pulse pressure with bisferiens pulse (biphasic peaks)
Before initiating cardiopulmonary bypass in the patient with aortic regurgitation,
cardioplegia must be injected retrograde (through the coronary sinus) or directly into each coronary ostia
Anesthetic goals for aortic insufficiency for heart rate, heart rhythm, preload, afterload, contractility, and pulmonary vascular resistance are:
full, fast, and forward
heart rate–> elevate
heart rhythm–> NSR
preload–> maintain or increased
afterload–> decrease
contractility–> maintain
pulmonary vascular resistance–> maintain
Acute aortic insufficiency leads to
rapid CV instability
left ventricular failure can result from acute dilation leading to increased wall tension and impaired contractility
Acute AI is usually caused by
endocarditis
can also result from aortic root dissection from aneurysm or trauma
Conditions associated with chronic AI include
valvular calcification
Marfan syndrome
Ehler-Danlos syndrome
ankylosing spondylitis
Etiologies of aortic regurgitation include
incompetent valve or dilation of the aortic root or its supporting structures
Conditions that increase the regurgitant volume include:
- bradycardia (longer diastolic filling time)
- increased SVR (increased aorta-LV pressure gradient)
- large valve orifice (larger area for the blood to return through)
