mitral stenosis

Question 1

etiology? and mimicer?

Answer 1

rheumatic fever is the most common cause. also calcifications, SLE/RA

mimic MS: endocarditis of the mitral valve with large vegitations

Question 2

pathophysiology?

Answer 2

1. forward heart failure: obstruction of blood flow into the LV -> decreased end diastolic LV volume -> decreased stroke volume and cardiac output
2. backward heart failure: high LA pressure -> backup of blood into the lungs and pulmonary edema -> pulmonary hypertension and RV hypertrophy

Question 3

clinical features?

Answer 3

symptoms progress overtime from asymptomatic to heart failure

1. SOB
2. fatigue
3. Atrial fibrillation due to stagnation of blood in LA (stroke)
4. hoarseness due to compression of laryngeal nerve
5. dysphagia due to compression of esophagus
6. symptoms of HF (PND, orthopnea, LL edema)

Question 4

clinical findings?

Answer 4

mitral facies (malar rash due to low CO and vasoconstriction)

auscultation:
diastolic murmur in 5th intercostal space mic-clavicular line heard best when they lie on their side, loud S1, opening snap after S2

Question 5

diagnosis?

Answer 5

transthoracic echo is the most imp initial step:
-reduced mitral valve area (>1.5 cm2 is severe)
-thick calcified leaflets

ECG may show a fib, LA enlargement (bifid pwave, RV hypertrophy)

xray may show straightening of the left heart border, widening carina, double density sign (silhouette of LA appears close to RA), and pulmonary edema due to HF if chronic

Question 6

treatment?

Answer 6

serial TTE examinations to monitor progression

if afib is present, give warfarin until INR reaches 2.5

BB for heart rate control (?)
treat HF accordingly

mitral valve balloon commissurotomy if severe MS
open commissurotomy and mitral valve replacement