Cardiology Lecture 4 -- Mitral Valve Lesions Flashcards
(32 cards)
What is the ultimate diastolic dysfunction?
Fixed obstruction to filling of LV (mitral stenosis)
Most common cause of mitral stenosis
Rheumatic heart disease leading to hockey stick pattern of mitral valve leaflets
When do symptoms of mitral stenosis typically manifest?
In 30’s or 40’s
Heart changes due to mitral stenosis
LA dilates = increase in left atrial P to overcome obstruction to LV filling (slow filling)
Mitral stenosis: Effect on P graph
Shallow y descent (atrial P) since atrial emptying is prolonged P gradient throughout diastole with increased gradient at atrial kick
2 symptoms associated with mitral stenosis
Acute pulmonary edema
Sudden dyspnea (often associated with pulmonary edema)
Explain why acute pulmonary edema occurs in mitral stenosis
Sudden tachycardia = no time to fill LV = increased LAP
+
Sudden tachycardia –> atrial fib –> no atrial kick due to fib –> increase LAP
= sudden P backup –> acute pulmonary edema
Describe the behavior of the murmur in mitral stenosis
Pandiastolic rumble
Mild stenosis = initial gradient to filling with an increase gradient at kick
Severe stenosis = duration of rumble increases with accentuation at kick
Describe the behavior of S1 in mitral stenosis
Opening snap = increase intensity of S1 since dp/dt is increased
Where do you listen for mitral stenosis
Bring apex forward, best if patient lies in left lateral decubitus position (best heard with bell)
Management of mitral stenosis
- Diuretics to decrease LAP
- Beta blockers to keep HR low to decrease LAP
- Surgery is not required (valvuloplasty an option)
Define valvuloplasty
Catheter inserted to balloon open the valve (split commissures)
What is the benefit of valvuloplasty for mitral stenosis
Long term (11 - 12 years)
2 types of mitral regurgitation
Acute
Chronic
Common cause of chronic mitral regurgitation
Mitral valve prolapse (into the left atrium)
What kind of overload is chronic mitral regurgitation associated with?
VOlume overload condition
Heart sound associated with chronic mitral regurgitation
S3
Why isn’t mitral regurgitation a pressure overload condition?
When LV contracts, the blood can go either forward through the aortic valve or backwards through the mitral valve (which is easier since LAP is already so low), so afterload is not increased since preload is either normal or decreased
Decscribe the isovolumetric phases in chronic mitral regurgitation
Non-existent
Describe the murmur associated with chronic mitral regurgitation
Pansystolic murmur due to gradient between LV and LA
Where do you listen for mitral regurgitation?
Heard best at apex (displaced)
Describe the behavior of the murmur of chronic mitral regurgitation post PVC (early contraction). Why is this significant?
Compensatory increase in intensity DOES NOT occur in the next beat, so you can differentiate from aortic stenosis in this way
Most common symptom associated with chronic mitral stenosis
dyspnea
What is a sign that the chronic mitral regurgitation is severe?
Diastolic rumble due to increased flow through the mitral valve (flow murmur)
