Mitral Stenosis Flashcards
Causes of mitral stenosis?
Aging calcification
Endocarditis
Rheumatic fever
Symptoms of mitral stenosis?
Diastolic murmur
Dyspnea
Orthopnea
Fatigue
What conditions are associated with mitral stenosis?
Anemia
Pregnancy
Stress
What is the primary pathophysiological problem with mitral stenosis?
Obstruction to LV filling
What problems can occur due to this under loaded LV from obstruction to filling with MS?
decrease in preload > under perfusion of organs
fatigue
venous stasis, thrombus, emboli
What pressure gradient is considered severe mitral stenosis?
Mean gradient higher than 10 mmHg
What are the secondary compensatory mechanisms with MS?
Increased blood volume
Left atrial overload
Increased LA pressure maintains LV filling and SV at rest and normal HR
What are the consequences of the compensatory mechanisms of MS?
Left atrial enlargement
What can occur due to left atrial enlargement with MS?
Biphasic P waves
Atrial dysrhythmias
Blood stasis, thrombus, emboli
With volume increasing in the LA with MS, what clinical implications does this have?
Pulmonary hypertension from increased PVR
-leads to RV failure, pulmonary congestion, peripheral edema and ascites
The impaired LV filling that occurs with MS requires what?
Atrial kick
Adequate diastolic fill time
How is LV function with MS?
LV function is preserved
What are the anesthetic HR goals with MS?
Avoid tachycardia
-decreased diastolic time impairs LV filling
What are the anesthetic SVR goals with MS?
Maintain SVR
-decreases in SVR associated with increased HR
What else can be avoided to help with anesthetic goals with MS?
Avoid increases in PVR
-they are already prone to pulmonary HTN
What is the number 1 anesthetic goal with MS?
Avoid tachycardia
What medications are important for MS patients?
Digoxin -continue to maintain SR and control HR Anticoagulant (Coumadin is common) - +/- based on risk/benefit Consider endocarditis prophylaxis
What type of dysrhythmia is common with MS?
Atrial dysrhythmias
What can be used to decrease HR with MS patients?
Digoxin
BB
CCB
What INR is therapeutic?
2.5-3.0
Why could anxiety be problematic with MS?
It increases HR
-preop anxiolytics
What are MS patients sensitive to when it comes to drug effects?
Respiratory depressants
What about induction meds with MS?
No ketamine
Muscle relaxants with MS?
Ensure minimal effects on HR and SVR
What about anesthetic gases with MS?
ISO, SEVO, DES are fine
Avoid Nitrous because it increases PVR
What about regional with MS?
Anticoagulation issues
SVR effects
What monitor could help if MS is severe?
CVP
-monitor pulmonary HTN, RV failure
Describe the use of a PAC with MS
Relationship of PCWP and LVEDP altered by mitral dysfunction
-PCWP reflects LA pressure
She calls it not useful with MS
