Mitral Regurgitation

Question 0

Two mechanisms of MR

Answer 0

Functional

Organic

Question 1

Two broad causes of MR

Answer 1

Ischemic or nonischemic

Question 2

Carpentier functional type I MR

Answer 2

annular dilatation, normal valve leaflets

Question 3

Carpentier functional type II MR

Answer 3

Leaflet prolapse or excess motion

Question 4

Carpentier functional type IIIa MR

Answer 4

Leaflet restriction in systole and diastole from leaflet or chordal retraction or thickening

Question 5

Carpentier functional type IIIb MR

Answer 5

Leaflet restriction or tethering on diastole from papillary muscle displacement

Question 6

What is the major cause of MR in the US? What percentage?

Answer 6

Degenerative (60-70%)

• primary myxomatous disease
• primary flail leaflets
• annular calcification

Question 7

After degenerative, second most common cause of MR?

Answer 7

Ischemic MR 20%

Question 8

Third most common causes (2) of MR?

Answer 8

Endocarditis 2-5%

Rheumatic 2-5%

Question 9

MCC of MR in developing countries?

Answer 9

Rheumatic

Question 10

What is the adaptive response of the LV to chronic MR?

Answer 10

LV dilatation with new sarcomeres added in series which leads to eccentric LV hypertrophy.

Question 11

What EF portends higher risk for mitral surgery?

Answer 11

EF <60%

Question 12

Severe MR vena contracta (most narrow diameter of jet flow)

Answer 12

> 0.7cm

Question 13

Severe MR effective regurgitant orifice (ERO)

Answer 13

> 0.4sqcm

Question 14

Severe MR regurgitant volume

Answer 14

> 60 mL

Question 15

Severe MR regurgitant fraction

Answer 15

> 50%

Question 16

Severe MR jet area

Answer 16

> 40% of LA area

Question 17

Indications for repair of MR

Answer 17

Symptoms or
LV dysfunction, new onset atrial fibrillation, or pulmonary hypertension.
Symptomatic acute severe MR

Question 18

End systolic volume as indicator for MR repair

Answer 18

> 55 mm.

Question 19

MR repair vs replacement 10 year survival?

Answer 19

Repair 68% vs 52% for replacement.

Question 20

What is the scoring system to determine whether mitral repair is reasonable? What score has best prognosis?

Answer 20

Wilkins score. Components include leaflet mobility, leaflet thickening, and leaflet calcifications.
Score <8 has the best prognosis.

Question 21

Primary treatment for posterior leaflet prolapse

Answer 21

Quadrangular resection with annuloplasty ring.

Question 22

Primary treatment for posterior leaflet prolapse due to Barlow’s disease (excessive tissue)

Answer 22

Quadrangular resection of posterior leaflet and sliding plasty of P1 and P3 to avoid SAM

Question 23

Primary treatment for commisural prolapse

Answer 23

Commisuroplasty or a resection of the prolapsed area with sliding plasty.

Question 24

Primary treatment for anterior leaflet prolapse

Answer 24

Triangular resection, placement of artificial chords, chordal transfer from the posterior to the anterior leaflet. Less frequently, chordal or papillary muscle shortening.

Question 25

Primary method for exposure of the mitral valve.

Answer 25

Left atriotomy

Question 26

When should a transseptal exposure of the mitral valve be used?

Answer 26

Reoperation, aortic prosthesis, small LA, or if access is difficult.

Question 27

Risk factors for AV groove disruption

Answer 27

Mitral annular calcification, women, elderly. Usually occurs when you lift the heart.

Question 28

Risk factors for SAM

Answer 28

Redundant leaflet tissue, small annuloplasty ring, long posterior leaflet that can push the anterior leaflet into the LVOT. Also occurs in patients with HOCM or post MI.

Question 29

Medical treatment of SAM

Answer 29

Volume loading and treatment of tachyarrhythmias with beta blockers. Avoid IABP or inotropes as these can exacerbate SAM.