Mitral Valve

Question 1

What are factors that suggest mitral valve repair for moderate MR during CABG is beneficial compared to CABG alone?

Answer 1

LVESVI >60
LVEDD >50
Presence and extent of LV scar tissue or basal aneurysm of inferior-posterior LV dyskinesia
Small LCX and RCA circulations

Question 2

What are Carpentier’s principles of reconstructive valve surgery?

Answer 2

1. Preserve or restore full range of leaflet motion
2. Create a large surface area of coaptation
3. Remodel and stabilize the entire annulus

Question 3

What position do you place a mechanical mitral valve in?

Answer 3

Anti-anatomic, because placing it in the anatomic position could result in preferential flow through the anterior leaflet and thrombus formation on the posterior leaflet.

Question 4

What percentage of mechanical mitral valve patients complain about the “ticking” sound at 1 month and 1 year?

Answer 4

20% and 10% respectively

Question 5

What percentage of patients can hear the “ticking” sound of a mechanical valve?

Answer 5

Approximately 70-80% can hear it, 50% can hear it clearly

Question 6

What are the indications for MV repair/replacement?

Answer 6

Severe symptomatic and LVEF >30% I B
Severe symptomatic and LVEF <30% IIb C
Severe and severely symptomatic (NYHA 3-4), suitable for clip and prohibitive risk of surgery IIb C for MitraClip
Severe asymptomatic if:
LVESD >40mm I B
LVEF <60% I B
new onset A-fib or PASP >50mmHg IIa B
Likelihood of successful repair over 95% and mortality <1% IIa B
progressive increase in LV size or decrease in LVF on serial imaging studies IIa C
Moderate if:
concomitant cardiac surgery IIa B

Question 7

What are the incisions for mitral valve access?

Answer 7

1. Sondergaard’s (Waterston’s) groove
2. Transseptal
3. Superior septal
4. Left atrial dome (superior approach)
5. Transection of the SVC and LA atriotomy
6. Dubost approach (transverse right atriotomy extending into the RSPV and then incise through the septum into the left atrium and mitral valve)
7. Transaortic approach (standard aortotomy, for AVR+MVR)
8. LV approach
9. Right Thoracotomy approach
10. Left Thoracotomy approach
11. Cardiac autotransplantation

Question 8

What are the echo criteria for mitral stenosis?

Answer 8

Mitral valve area <1.5cm2
Mitral valve pressure half time <150ms
(Mitral valve mean gradient >10mmHg (high heart rate will overestimate stenosis))

Question 9

What are the hemodynamic criteria for mitral stenosis?

Answer 9

PASP >50mmHg

severe LA dilation

Question 10

What are the medical therapies in rheumatic MS?

Answer 10

beta-blockers and ivabradine

Question 11

What are the four major causes of MS?

Answer 11

Rheumatic, calcific and radiation induced and iatrogenic (mitral valve repair with small ring)

Question 12

What are the guideline recommendations for intervention in mitral stenosis?

Answer 12

Class 1 A - Symptomatic (NYHA 2-4) severe rheumatic MS with favourable valve morphology and less than 2+ MR in the absence of LA thrombus should get PMBC if done at a comprehensive valve center

Class 1 B - Symptomatic (NYHA 3-4) severe rheumatic MS not a candidate for PMBC, previous failed PMBC, require other cardiac operations or no access to PMBC should get mitral valve repair/comissurotomy/replacement

Class IIa B - Asymptomatic severe rheumatic MS with favourable valve morphology and less than 2+ MR in the absence of LA thrombus but have elevated PASP >50mmHg, should get PMBC if done at a comprehensive valve center

Class IIb C Asymptomatic severe rheumatic MS with favourable valve morphology and less than 2+ MR in the absence of LA thrombus with new onset AFib, should get PMBC if done at a comprehensive valve center

Class IIb C In symptomatic patients (NYHA class II, III,
or IV) with rheumatic MS and an mitral valve area >1.5 cm2, if there is evidence of hemodynamically significant rheumatic MS on the basis of a pulmonary artery wedge
pressure >25 mmHg or a mean mitral valve gradient >15 mmHg during exercise, PMBC may be considered if it can be performed at a Comprehensive Valve Center

Class IIb C In severely symptomatic patients (NYHA class III or IV) with severe rheumatic MS (mitral valve
area ≤1.5 cm2 , Stage D) who have a suboptimal
valve anatomy and who are not candidates for
surgery or are at high risk for surgery, PMBC
may be considered if it can be performed at a
Comprehensive Valve Center

Question 13

What are the long term outcomes of successful PMBC?

Answer 13

Long-term follow-up has shown 70% to 80% of patients
with an initial good result after PMBC to be free of
recurrent symptoms at 10 years, and 30% to 40%
are free of recurrent symptoms at 20 years

Question 14

What do the guidelines say regarding calcific MS?

Answer 14

Intervention should only be considered if patients are severely symptomatic and refractory to medical therapy. PMBC and surgical commissurotomy are not options in these patients.

Question 15

What are the three major causes of acute MR?

Answer 15

Infective endocarditis - leaflet perforation or chordal rupture
Spontaneous chordal rupture - myxomatous MV disease
Acute papillary muscle rupture - MI (usually inferior)

Question 16

What are the medical/non-surgical therapies in acute MR?

Answer 16

vasodilator therapies (sodium nitroprusside, nicardipine), IABP - both reduce afterload

Question 17

What is the difference between primary MR and secondary MR?

Answer 17

Primary MR is a disease of the mitral valve apparatus

Secondary MR is a disease of the ventricles or atria

Question 18

What are the echo criteria for severe MR?

Answer 18

Central jet MR >40% LA or
holosystolic eccentric jet MR
Vena contracta ≥0.7 cm
Regurgitant volume ≥60 mL
Regurgitant fraction ≥50%
ERO ≥0.40 cm2
Angiographic grade 3+ to 4+

Question 19

What is the effect of anesthesia on MR?

Answer 19

Anesthesia lessens afterload, preload and mitral valve closing force, reducing MR, so decisions about severity of MR should be evaluated prior to the OR

Question 20

What is global longitudinal strain and how is it used in timing of intervention in MR?

Answer 20

Global longitudinal strain is an echo measurement that assess change in longitudinal length as a percentage of baseline. It has been shown to be more predictive of LV dysfunction than LVEF.

Question 21

What are the indications for surgery in primary MR?

Answer 21

Class 1 B - Symptomatic severe MR
Class 1 B - Asymptomatic severe MR with LVEF <60% or LVESD >40mm
Class 1 B - Mitral valve repair > replacement if anatomically possible in primary degenerative MR
Class 2a B - Asymptomatic severe MR with LVEF >60% and LVESD >40mm, mitral valve repair should be performed if likelihood of repair is >95% and <1% risk of mortality
Class 2b B - Asymptomatic severe MR with LVEF >60% and LVESD >40mm and increasing LV size or reduced LVEF on 3 or more serial imaging studies, mitral valve surgery may be performed

Question 22

What are the indications for transcatheter MV repair?

Answer 22

Class 2a B - . In severely symptomatic patients (NYHA class III or IV) with primary severe MR and high or
prohibitive surgical risk, transcatheter edge-toedge repair (TEER) is reasonable if mitral valve
anatomy is favorable for the repair procedure
and patient life expectancy is at least 1 year.

Class 2a B - In patients with chronic severe secondary MR related to LV systolic dysfunction (LVEF <50%)
who have persistent symptoms (NYHA class
II, III, or IV) while on optimal GDMT for HF
(Stage D), TEER is reasonable in patients with
appropriate anatomy as defined on TEE and
with LVEF between 20% and 50%, LVESD ≤70
mm, and pulmonary artery systolic pressure
≤70 mmHg

Question 23

What are the indications for rheumatic mitral valve repair for MR?

Answer 23

Class 2a B - In symptomatic patients with severe primary MR attributable to rheumatic valve disease,
mitral valve repair may be considered at a
Comprehensive Valve Center by an experienced
team when surgical treatment is indicated, if a
durable and successful repair is likely.

Question 24

What is the class III indication in mitral valve surgery?

Answer 24

Class III - In patients with less than half of posterior leaflet prolapse, MVR should not be performed before a MV repair has been attempted at a comprehensive valve center

Question 25

What is the indication for surgery in secondary MR?

Answer 25

Class IIa B - In secondary severe MR, patients undergoing CABG for myocardial ischemia should receive mitral valve surgery

Class IIb B - In patients with chronic severe secondary MR
from atrial annular dilation with preserved
LV systolic function (LVEF ≥50%) who have
severe persistent symptoms (NYHA class III
or IV) despite therapy for HF and therapy for
associated AF or other comorbidities (Stage D),
mitral valve surgery may be considered

Class IIb B - In patients with chronic severe secondary
MR related to LV systolic dysfunction (LVEF
<50%) who have persistent severe symptoms
(NYHA class III or IV) while on optimal GDMT
for HF (Stage D), mitral valve surgery may be
considered

Class IIb B - In patients with CAD and chronic severe
secondary MR related to LV systolic
dysfunction (LVEF <50%) (Stage D) who are
undergoing mitral valve surgery because of
severe symptoms (NYHA class III or IV) that
persist despite GDMT for HF, chordal-sparing
mitral valve replacement may be reasonable
to choose over downsized annuloplasty
repair