Mitral Regurgitation Flashcards
1
Q
MR Etiology
A
- Rheumatic
- Degenerative
- Ischemic
2
Q
MR Mechanisms
A
- Leaflet retraction (fibrosis or calcification)
- MV annular dilation
- Chordal changes (rupture, elongation, shortening or tethering)
- LV dysfunction +/- papillary muscle involvement
3
Q
MR Presentation of Sx
A
- Asymptomatic
- DOE
- CHF
4
Q
Classic PE finding of MR
A
Holosystoic murmur heard at apex, radiating to axilla
5
Q
Characteristics of Myxomatous MR
A
- Acquired: fibroelastic deficiency in older patients
- Congenital: excessive, weak fibroelastic connective tissue
- Leaflets: thickened and spongy
- Annulus: thickented and dilated
- Changes more pronounced in younger patients (Barlow syndrome)
- Less obvious is older patients
- Chordal rupture likely due to:
- Defective collagen
- Underlying papillary muscle fibrosis and dysfunction
- Posterior chorde most likely to rupture
6
Q
MR and Echocardiography
A
- Best overall diagnostic modality, can visulaize mechanism
- Quantitate regurgitation
- MV prolapse
- Directon of jet:
- Anterior (septal): posterior leaflet prolapse
7
Q
MR and Cardiac Catheterization
A
- Quantitate regurgitation
- Assess function of pulmonary hypertension
- Assess coronaries for CAD
8
Q
MCC of MR
A
MV prolapse
(2-6% of poplulation)
9
Q
Natural History of MR
A
- Prolonged asymptomatic phase
- Accelerated phase
- Ruptured chordae tendinae
- Men age > 45 subject to complications
- Sudden death rate: <1%/year
10
Q
Annual sudden death rate for MR
A
<1% per year
11
Q
MR indications for operation
A
- Acute symptomatic MR
- Symptomatic or Asymptomatic MR with LV dysfunction
- Mild (EF 50-60%, Systoic Dimension 45-50 mm)
- Moderate (EF 30-50%, Systolic Dimension 50-55 mm)
- Severe (EF < 30%, Systolic Dimension > 55 mm)
- Asymptomatic with AFib or Pulmonary Hypertension
- PA > 50 (rest) or >60 (with exercise)
12
Q
Surgical Approaches to MV
A
- Left thoracotomy (rare, mostly historical)
- Right thoracotomy
- Redo MVR or TV repair
- Median sternotomy
- Interatrial groove
- Interatrial groove + SVC detachment
- Superior via dome of LA
- Trans-septal
- Associated TV repair, Afib
- Partial sternotomy
13
Q
Techniques of MV Repair
A
- Reduction annuloplasty
- Triangular resection
- Quadrangular resection
- Sliding posterior leaflet repair
- Artificial chordae
- Posterior leaflet transfer
- Combined anterior leaflet augmentation and posterior reduction
- Anterior leaflet augmentation
14
Q
Operations for MR
A
- MV Repair
- Likely with posterior leaflet prolapase or ruptured chordae
- Less likely with anteiror leaflet prolapse
- Choradal Sparing MVR
- Bioprosthesis
- Mechanical
- Mitral homograft
15
Q
MV Repair Outcomes
A
- Hospital mortality (non-ischemic MR): 0-1%
- Mortality for IMR:
- Low-risk patients have improved hospital mortality with Repair over replacement
- No surival benefit for repair over replacement
- Survival after MVR/Repair + CABG worse for IMR compared to rheumatic or degenerative MR
