EXAM #2: MITRAL VALVE DISEASE Flashcards
What causes mitral regurgitation?
1) Rheumatic Heart Disease
2) Infective Endocarditis
3) Collagen-vascular disease
4) Cardiomyopathy
5) IHD
6) MVP
What valve structures are involved in mitral regurgitation?
- Leaflets
- Mitral annulus
- Chordae tendinae
- Papillary muscles
*Note that the annulus is what the leaflets are attached to
What disease processes will effect the mitral leaflets leading to MR?
1) Chronic Rheumatic Heart Disease
2) Infective Endocarditis
What disease processes will effect the mitral annulus leading to MR?
1) Dilation
2) Calcification
- More common in women
What disease processes will effect the mitral chordae leading to MR?
1) Infective endocarditis
2) Trauma
*Note that this can lead to ACUTE MR–which is really bad
What disease processes will effect the mitral papillary muscles leading to MR?
Ischemia
*Note that the posterior papillary muscle is more frequently involved
Why is acute MR an emergency?
- Pulmonary circulation is exposed to LV pressures
- Causes acute pulmonary edema
Why don’t patients with chronic MR develop pulmonary edema?
Over time the pulmonary circulation is able to adapt
What happens to the “impedance to LV ejection” i.e. afterload in MR?
Afterload is LOWERED
*BUT this causes dilation of the LV when the blood comes back from the pulmonary circulation and increases LV wall-tension
What happens to the EF with time in MR?
Early= high Late= low to normal
What happens to the left atrial pressure in MR?
Increased
What is the principal symptom of MR?
Dyspnea
- Exertional at first
- PND or orthopnea later
What are the 3x PE findings that are seen in MR?
1) Sharp/severe carotid pulses (higher SV)
2) Apical impulse is:
- hyperdynamic
- displaced left and downward
3) LA thrust at left parasternal area*
Filling of the LA during systole pushes the heart foward into the chest wall
How does S1 change in MR?
Soft
How does S2 change in MR?
Wider splitting and lound P2
*Aortic sound is earlier than normal
What is a common extra heart-sound associated with MR?
S3 b/c the LV is over-filled during diastole
How is the classic MR mumur described?
1) Holosystolic (S1-S2)
2) Level contour i.e. no cescendo/decrescendo
3) Radiates to axilla/ back
What correlates with the severity of a heart mumur?
Duration, NOT intensity
How is MR diagnosed?
Echocardiography
How can severity of MR be quantified?
Echo + doppler
What ECG changes may be seen with MR?
1) LAE*
2) RVH
3) A-fib
How is MR treated medically?
1) Treat LV failure
- Afterload reudction
2) Anticoagulate A-fib
3) Digitalis
4) Prophylaxis against infective endocarditis
What are the drugs of choice to reduce LV afterload?
ACEI
What is the treatment for acute MR?
Nitroprusside + Dobutamine
How is MR repaired surgically?
1) Valve repair
2) Valve replacement
What is the primary etiology of mitral stenosis (MS)?
Rheumatic Fever
What is the normal size of the mitral orifice?
4-6 cm
What is the size of the mitral orifice in mild MS and critical MS?
Mild= 2cm
Critical= 1cm or less
Describe the hemodynamic sequelae of having a stenoic mitral valve.
1) Increased pressure gradient to maintain CO
- LA pressure is ALWAYS higher than LV
2) Increased LA pressure= increased pulmonary pressure
What may be the first symptom of MS?
Systemic embolization
I.e. CVA (50% of the time)
What are the signs of MS on PE?
1) Mitral facies
2) Arterial pulses low/normal
3) Apical impulse inconspicuous to absent
How does S1 change in MS?
S1 is LOUD
How does S2 change in MS?
P2 is later and louder
When does the opening snap occur in MS?
Between P2 and S3
Describe the classic mumur heard in MS?
- Low-pitched, rumbling
- Apex
- Opening snap
What is a Graham-Steel mumur?
Sign of severe pulmonary HTN
What is the cornerstone of diagnosis in MS?
Echocardiography
What ECG changes are seen with MS?
1) LAE
2) RVH
3) A-fib
Where does MS have a shorter natural history?
Tropics
In India it can be critical in childhood
How is MS treated?
1) Prophylaxis against endocarditis
2) Avoid strenuous exercise
3) Anticoagulant
4) NSR
5) Reduce salt and water intake
What is the definitive treatment for MS?
Valve replacement
