Quiz 6 Valvular Heart Disease Flashcards
At what levels can Aortic Stenosis occur?
Valvular
SubValvular
Supravalvular
What kinds of valvular stenosis can occur?
- Calcification & fibrosis of normal aortic valve (very common)
- Calcification & Fibrosis of congenital bicuspid AV (Higher incidence of stenosis ~ 40yrs old)
- Rheumatic - Uncommon since antibiotics
What is the normal aortic valve area?
2-4 cm2
In Severe aortic stenosis, what might the valve area be?
< 1 cm2
What is the normal LV mean peak gradient?
> 50 mmHg
** In severe AS, PG can be very low
What two factors can be used to judge the degree of stenosis?
Pressure
Valve area
Increased Pressure will lead to concentric or eccentric LVH?
Concentric
Increased Volume will lead to concentric or eccentric LVH?
Eccentric
Why is keeping a pt in SR so important for a pt with severe Aortic Stenosis?
SR is crucial to keep atrial kick. Atrial kick contributes up to 20% of ventricular filling in a normal heart and up to 40% in an ailing heart. Avoid A-fib and cardiovert early for acute changes
Should you try and keep a pt with AS slightly tachycardic?
No. Optimal HR is 60-80.
Why is tachycardia/Bradycardia bad for pts with stenotic lesions?
Tachy - decreased diastolic filling time leads to ischemia
Brady - leads to low CO due to fixed stroke volume
How should you treat hypotension for a pt with AS, Phenylephrine or Ephedrine?
Phenylephrine - alpha agonist effect will cause vasoconstriction, increase SVR and BP. Ephedrine would not be best due to beta 1 effects (increased HR).
**Can also use Norepi
Can placing a pt with AS in Trendelenburg be beneficial if pt is hypotensive?
yes. Can raise BP by 20 mmHg
A pt with AS has low preload and tachycardic. Should they get a spinal or epidural for the their case?
Neither - can cause vasodilation of Lower extremities and decrease SVR and BP.
Should you avoid benzos in management of AS?
No. for frail or elderly, can give smaller dose or none at all
When you are taking a pt with AS back to the OR, is it best to have an Arterial line pre-induction or can you wait until post-induction?
Pre-induction is best
Besides an Arterial line for a pt with AS, what other monitoring equip should this pt have?
CVP, PAC, TEE
Why is Systolic Anterior Motion with LVH a concern?
If LV is underfilled, MV can come down and touch septal wall of hypertrophied LV - obstructing outflow
How do you treat a pt with LVH and SAM?
Fluid Volume and Beta Blockers
A pt with acute Aortic regurgitation, will they have dilated LV?
No. will lead to increased LVEDP + LVEDV –> acute pulmonary edema
A pt with acute aortic regurg, could this be emergent?
yes and surgery is often required.
** Treat with inotrope and vasodilator (Epi + nipride or milrinone)
What is the 4 “F’s” for a regurgitant lesion?
Fast, Forward and Full
Just kidding, there’s only 3 F’s.
What heart rate is optimal for aortic regurg?
slightly tachy - 90 bpm
What medication is preferred for treating high afterload in a pt with AR?
Sodium nitroprusside
Should an intra aortic balloon pump be used in a pt with Aortic Regurg?
No, contraindicated
What medications would be beneficial for RSI in a pt with acute aortic regurg?
Ketamine and Succ
What are the Triad of Symptoms related to Aortic Stenosis and life expectancy?
Angina - 5yrs from onset
Syncope - 3-4 yrs
CHF - 1-2 yrs
What is the most common congenital reason for Aortic Stenosis?
Bicuspid aortic valve
What is the most common acquired reason for aortic stenosis?
senile followed by rheumatic
What is the most common cause of Mitral Stenosis?
Rheumatic heart disease
What are some of the signs of MS?
Fatigue, CP, palp, SOB, paroxysmal nocturnal dyspnea, pulm edema, hemoptysis, hoarseness due to compression of RLN by distended left atrium and enlarged pulm artery
When would you consider doing surgery on a pt with MS?
When their mitral valve area is < 1 cm2 with NYHA class III or IV dyspnea
With all stenosis, what are 2 things you would want to maintain?
Sinus rhythm and normal HR (60-80)
What are some things you would want to avoid in a pt with MS?
Hypercarbia Acidosis Hypothermia SNS activation Hypoxia
If a pt has pulm HTN, what could you do to do?
Start supplemental oxygen
How could you control the HR for a pt with MS?
B-blockers, Dig, Ca-Channel blockers, amiodarone
What is the single most useful drug to use on pts with severe MS?
Esmolol 10-20mg bolus, 50-100 mcg/kg/min
**even with CHF and Pulm Edema
What anesthetic gas should be avoided on a pt with Pulm HTN?
N2O
What NDMR should be avoided on the pt with MS?
Pancuronium - can cause tachycardia
Why would a pt with Mitral regurg be more likely to have atrial arrhythmias?
Due to dilated LA. LA can be massively dilated
Volume overload in a pt with mitral regurg can lead to __________ and ___________ enlargement
LV and LA
What 3 factors can determine the severity of Mitral Regurg?
Pressure gradient against LA and LV
Size of regurgitant orifice
Duration of ventricular systole
Why would you want to use vasodilators like NTG or nitroprusside for regurgitant lesions?
Helps decrease SVR and keeps forward flow of blood
What can be unmasked after repair of MR?
LV dysfunction may have been masked by its decreased ability to offload into the LA
What is a primary reason for Tricuspid regurg?
rheumatic, inf endocarditis, carcinoid, Epstein Bar, trauma
In a pt with Tricuspid regurg and R heart failure, what other problems may be manifested?
hepatomegaly
Ascites
Be sure to look through slides at the anesthetic management and weaning from CPB
yeah
What is the most common cause of Mitral Regurg?
Myxomatous degeneration: breakdown of the valve
What things determine the severity of mitral Regurg?
- pressure gradient between LA + LV
- size of regurgitant orifice
- duration of ventricular systole
What should you avoid with tricuspid Regurg?
Pulm htn and high PVR
For tricuspid Regurg, how do you want the preload, high or low?
Normal to high preload
** treat hypotension with inotropes and volume (vasoconstrictors may worsen pulm htn)
