Sara: Anesthesia for Left Side Valve Disease Flashcards
What 2 conditions can lead to pulmonary issues?
regurge
stenosis
With stenosis, what is important?
contractility
With regurge, what is important?
Decreased afterload is really important.
What is important in all valve lesions?
preload
What are important during the preoperative evaluation? (3)
Detailed history of disease, listen to heart
AHA protocol and guidelines
Echo w/in 6 months for all valvular lesions
What is the most common MAJOR valve lesion?
aortic stenosis
What are the common causes of aortic valve lesions? (3)
congenital bicuspid valve
degeneration
atherosclerotic/rheumatic
You note LVH on preop ECG and you hear a systolic murmur.
Systolic mumur = _____________.
related to flow
All diastolic murmurs are pathological. True or false?
True
In normal valves, no real pressure gradient across the valve. True or false?
true
What happens as a result of stenosis relating to pressure gradient?
Increase stenosis = increase pressure gradient
Otherwise, there is no real pressure gradient in normal valves.
What are consequences of aortic stenosis? (5)
Avoid hypotension!
Atrial kick contributes to 25% of filling instead of 15-20%
Increase in LV systolic and diastolic presssures
Longer ejection time
Decrease in aortic pressure
Note: All lead to decreased O2 supply → ischemia
What is the triad of stenosis?
Angina (even with patent coronaries)
Syncope
Heart failure
What is normal EF?
55%
How do you anesthetically manage AS pts in relation to preload? (4)
Keep intravascular volume normal to high
Avoid venous dilation (NO EPIDURAL/SPINAL)
HR slow to normal ( to allow greater diastole time to increase filling)
Aggressive treatment of atrial rhythm
How do you anesthetically manage AS pts in relation to afterload? (2)
Keep diastolic pressure up to perfuse coronaries
Aggressively treat hypotension with alpha agonist
Causes of valvular disease due to: (3)
congenital
rheumatic
degenerative (calcification is most common)
Critical aortic stenosis is when the aortic valve orifice is reduced to ____-_____ cm2.
0.5 - 0.7
Normal is 2.5-3.5 cm2
What is hypertrophic cardiomyopathy characterized by? (2)
dynamic obstruction of left ventricular outflow tract
associated with mitral valve abnormality
- systolic anterior motion (SAM)
- mitral regurgitation
What factors tend to worsen hypertrophic cardiomyopathy ventricular outflow? (3)
increased contractility
decreased ventricular volume
decreased left ventricular afterload
Anesthetic management of HOCM? (5)
Volume loading
Decrease contractility
Beta blockade
Keep systemic pressure high
TEE vs PA catheter
Note: Phenylephrine and other pure alpha agonists are ideal vasopressors.
What is known as “disease of diastole”?
aortic regurge
Aortic regurgitation can be chronic or acute. True or false?
True
What changes to the ventricle for pt with aortic regurge?
hugely dilated heart
produces volume overload of the left ventricle
What are the consequences of aortic regurge? (3)
“Eccentric” hypertrophy dilatation
Very high LV CO, but low SV
Tachycardia and peripheral vasodilation to maintain forward flow is good
How is acute vs. chronic regurge characterized by? (
Chronic allows LV to dilate and acute does not → LVED
Chronic sees higher volumes vs acute sees higher pressures
What is aortic regurge also known as?
aortic insufficiency
Anesthetic management of AI/AR relating to preload: (4)
Keep volume high
Keep SVR high
High normal heart rate is best
Avoid bradycardia, want more time in diastole
Anesthetic management of AI/AR relating to contractility: (2)
Maintain contractility
Use epi, dobutamine
Anesthetic management of AI/AR relating to afterload: (1)
Reduced afterload is essential
Use arterial not venous dilators
Note: Arterial dilator (nicardipine). Avoid nitros.
Mitral stenosis is most commonly ____________.
Affects more males/females?
rheumatic
pregnant females (2:1)
In mitral stenosis, what anatomic changes occur?
dilated atrium resulting in SVT, particularly afib
blood stasis promotes thrombi to form
loss of normal atrial systole
What in short do you need to remember relating to mitral stenosis?
pressure gradient b/n LA and LV needed to get through the thickened valve
What do you think happens to ventricular filling when there is mitral stenosis?
What happens as a result? (3)
decreased
- Left atrial dilatation
- A-fib
- Pulmonary edema
Anesthetic management relating preload for MS: (4)
Keep volume high, but not too high (fine line)
Avoid venodilation
Low heart rate is best (tachy leads to PEdema)
Aggressive treatment for tachycardia
Anesthetic management of MS relating to afterload: (1)
maintain in normal range
**Unloading is pathology of LV
What are the consequences of MR? (4)
Left atrial dilatation → a fib
Left ventricular dilatation (eccentric)
Low forward CO syndrome
Biventricular failure
Anesthetic management of MR relating to preload: (1)
high normal HR is best
Anesthetic management of MR relating to contractility: (1)
Keep ventricular size down to maintain forward CO.
Anesthetic management of MR relating to afterload: (1)
Reducing afterload is important!
To summarize, for stenotic lesions: (2)
for regurgitant lesions: (2)
preload dominates (CPP in AS), HR low
reduce afterload, HR high
