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What is normal surface area of mitral valve?

what mitral valve area does a pressure gradient occur?

what mitral valve area do symptoms of severe MS occur

a. 4-6 cm2

b. 2cm2

c. 1 cm2


What is natural history of mitral stenosis

Symptomatic on exertion when MVA becomes <2.5cm

Symptomatic at rest when <1.5

Natural progression of MS causes valve area reduction at 0.1 to 0.3 per year

Progression from onset of RF to onset of signs of MS takes 10 to 20 years

Pulmonary hypertension >50mmHg the mean survival is 3 years


What is natural history of Mitral stenosis

exertional symptoms at MVA < 2.5cm2
rest symptoms at MVA < 1.5 cm2
natural progression of MS is about 0.1 to 0.3 cm2
The progression from onset of RF to signs of MS takes about 10 to 20 years
the progression from signs of MS to mild symptoms of MS takes 10 to years
the 10 year survival is 80% in pts with NHYA I or II
10 year survival in NHYA III or NHYA IV is 10 to 15%
Pulmonary hypertension the mean survival is 3 years


List poor prognostic features of MR include

1) symptoms for > 1 year
2) atrial fibrillation
3) age > 60 years
4) EF < 50%


What are symptoms of MR

Fatigue, weakness--related to low cardiac output
Dyspnea, orthoponea and PND
Pulmonary hypertension and right heart failure


What are the signs of MR

Displaced volume-loaded apex beat
Apical thrill
3rd heart sound
Apical pansystolic murmur--radiating to the axilla
Apical diastolic flow murmur
Right ventricular heave and an increased pulmonary compliance of the 2nd heart sound


What are the causes of mitral stenosis

1) Rheumatic fever (Lancefield group A beta-haemolytic streptococcus
2) Congential parachute mitral valve
3) Endocardial fibroelasosis
4) Carcinoid syndrome
5) Cor triatriatum
6) left atrial myxoma
7) pulmonary vein stenosis


Symptoms of Mitral stenosis

Long latent period
Dyspnea, orthopnea, PND
Left atrial distention resulting in
a) atrial fibrillation and subsequent thrombo-embolic events
b) left recurrent laryngeal nerve compression presenting with hoarseness (Ortner's syndrome)
c) esophageal compression producing dysphagia
d) rarely, left main bronchus compression causing left lung collapse
Pulmonary hypertension
a) peripheral edema and ascities
b) hemoptysis due to distention and rupture of bronchial veins


What are the signs of mitral stenosis

Low volume pulse
irregular pulse
opening snap
loud S1
Mid-diastolic rumbling murmur loudest at the apex
Pulmonary hypertension
a) mitral facies
b) central cyanosis
c) loud P2
d) tricuspid regurgitation-pan-systolic murmur at the right sternal edge
f) pulmonary regurgitation--Graham steel early diastolic murmur on inspiration


What is etiology of ischemic MR

infarcted, ruptured or non-ruptured papillary muscles (type II)

Chronic ---restricted movement of P2 and P3 scallops of the posterior MV due to left ventricular dilation displacing the papillary muscles (Type IIIb)---functional dilation of the annulus (Type I).


Carpentiers' classification of MR

Type I: Normal leaflet motion

Type II: excess leaflet motion

Type III: restricted leaflet motion
a) during diastole
b) during systole


Classification of different degrees of MR

Factor Mile Moderate Severe
Jet area (% of LA area) <20 20-40% > 40%
Vena contracta < 0.3 0.3 to 0.7 > 0.7
Regurgitant volume (ml) <30 30 to 60 > 60
Regurgitant fraction(%) < 30 30 to 50 >50
Effective regurgitant <0.2 0.2 to 0.4 > 0.4
orifice aea


Describe Barlows diseasae

Prolapse is defined as >2mm billowing of the anterior or posterior leaflet beyond the annular plane into the left atrium with or without MR

familial, non-familial, associated with Marfan Syndrome

Histological analysis--myxomatous proliferation of acid mucopolysaccharides withing the zona spongiosa of the mitral valve leafletsthinning and elongation of the chordae tendinae.


What are methods to measure Mitral valve Area

1) Planimetry: short axis view on 2D echocardiography

2) pressure half-time: MVA = 220/PHT

3) continuity equation:

4) Gorlin equation MVA = CO/ 38 x HR x DFO x square root of mean gradient


What are determinants of the Wilkins mitral stenosis score

Leaflet mobility
Leaflet thiickening
Leaflet calcification
subvalvular thickening

Each scores between 0 and 4 with max score at 16

A Wilkins score of > 9 suggests the lesion unlikley to be amenable to PMBV


List different surgical repair techniques for mitral valve disease

Posterior MVL prolapse
1) quadrangular or triangular resection
2) sliding annuloplasty
3) artificial chord implantation
Anteior MVL prolapse
1) triangular resection 2) artificial chord implantation/ chordal transfer
Bileaflet MV prolapse
1) leaflet resection
2) artificial chord implantation
3) Alfieri stitch
4) MV replacement
Partial papillary muscle rupture
1) reimplantation of the papillary muscle
Complete papillary muscle rupture
1) MVR


What are the surgical approaches to the mitral valve

1) Standard left atriotomy
Mobilise the pericardial reflections around the inferior and superior pulmonary veins
Sondergards groove is developed by reflecting the right atrium back over the left atrium
incision is made in the left atrium anterior and medial the right superior pulmonary vein and
and continued inferiorly
2) Bi-atrial trans-septal incision
3) Superior roof incision
4) Bi-atrial Dubost incision
vertical incision is made between the RSPV and Inferior pulmonary vein, which extends across the left atrium, right atrium, and interatrial septum


What is systolic anterior motion

SAM occurs when the tips of the mitral leaflets are displaced anteriorly into the left ventricular outflow tract

results in a venturi effect pulling on the mitral leaflets causing MR and left ventricular outflow tract obstruction.

During diastole the left ventricular outflow diameter is normal


What is physiology of SAM

Due to forward displacement of elongated mitral valve relative to the septum during systole

Venturi effect of the high-velocity blood stream carries the protruding edge of the anterior mitral leaflet toward the aortic annulus in early systole


What are consequences of SAM

Variable degree of mitral regurgitation

intraventricular gradient due to obstruction of the LVOT


What are risk factors for SAM

Excess height of posterior mitral valve leaflet (>1.5cm)
undersized annuloplasty ring
Narrow -aortic angle (130degree)
Excessively high PL/AL
Small LV cavity
inappropriate filling
rhytm disturbances
prominent septal bulge (HOCM)


What is intra-operative management of SAM

Increase preload
Increase afterload (partial aortic cross clamp) (increase MA 80-90 mmHg)
Stop inotropes
treat rhythm disturbances (avoid tachcardiac)
Check the LVOT peak gradient (it's critical...if < 40 its ok to go back to ICU if > 50 then go back on
also check for degree of MR (no more then mild)
CPB and do one of the following
add neochordae to displace posterior leaflet into ventricle
confirm appropriate annuloplasty ring size
check coptation depth < 12


What are advantages of repairing the mitral valve over replacing it

Greater freedom from mortality (operative and long term)
less Structural valve deterioration compared to bio
Less rates of re-operation
lower rates of infective endocarditis
decreased post op thrombo-embolism
lower rates of post operative hemorrhage complications related to anticoagulation
improved LV ejection fraction


What is Freedom from re-intervention for patients older then 70 for different mitral valve surgery

Repair of anterior mitral valve leaflet 78% at 10 years
Repair of posterior mitral valve leaflet 98% at 10 years
open mitral valve commissurtomty 80% at 10 years
close mitral valve comussurotomy 70% at 10 years
Porcine bioprosthesis 75% at 10 years
Bovine pericardial bioprosthesis 80% at 10 years
Mechanical prosthesis 98% at 10 years


List 5 echocardiographic findings of ischemic MR

Annular dilation
leaflet tenting
Leaflet coaptation below the plane of the annulus
papillary muscle displacement
regional wall motion abnormality (LV dilation
Failure of leaflet coptation during systole (loitering)
Papillary muscle rupture (acute)


list ecocardiographc findings of chronic MR

LV posterolateral wall motion abnormality
LV dilation
Normal leaflet morphology
restricted leaflet motion
plan of coaptation below the annulus
annular dilation
central jet of MR


What echo features should be assessed with ischemic MR

Valve tenting--valve being pulling towards in the ventricle
Tenting area
position/displacement of papillary muscle
left ventricular function/wall motion abnormalities
direction of jet (eccentric)
assess closure near medial commissure
MR severity


What would you accept as minimally acceptable indexed EOA for mitral valve?

> 1.2 cm2/m2

page 869 of Cohn states

EOAI of 1.3 to 1.5 as measured by continuuity equation may increase the risk of PPM


List 5 methods for repairing anterior mitral valve leaflet prolapse

transfer of secondary chord to the unsupported free edge
limited resection of a triangular wedge of anterior leaflet
alfieri stitch
chordal shortening: the papillary muscle is split and the chord is shortened by embedding it in the muscle
chordal replacement withe PTFE (size 5-0)
quandrangular resection of the posterior leaflet and transferring that portion of the posterior leaflet with its supporting chord--to the anterior leaflet.


What are techniques to repair anterior mitral leaflet

triangular resection
chordal shortening
chordal transfer
new chordae
alfieri stich


What is classification of AV groove disruption

Type 1: Dissociation at annulus
Type 2: Dissociation at the base of the papillary musclee
Type 3 dissociation between annulus and PM


What are risk factors for AV groove disruption

1% decreased by preservation of PML

age, female, annular calcification, annular abscess, complete resection of mitral valve leaflets, deep sutures, manipualtion after insertion, small LV, large valve size


How is atrioventricular disruption following mitral valve replacement treated

Patient back on CPB
remove the prosthetic valve
Implant a bovine pericardial patch across the atrioventricular groove
implant a smaller prosthetic valve with a low profile
avoid lifting the heart with the prosthesis in situ


What are intra-operative risk factors for AV groove separation in Mitral valve replacement

Oversizing of valve
Aggressive debridement of posterior annulus/posterior leaflet
Vigourous retraction
De-airing maneuvers
Bioprosthetic valve
Papillary muscle resection


List 3 essential anatomic components of myxomatous mitral valve prolapse

Diffuse leaflet thickening

annular dilation

interchordal ballooning of the mitral leaflets--- with or without elongated thinned or ruptured chords.


What are pathologic features of Fibroelastic deficiency

Occurs in Elderly
Short history of symptoms
Leaflets are thin and there is no excess tissue except in the prolapsing areas
annulus maybe dilated and/or calcified


What is pathologic features of Barlows disease

Younger patients
Long history of MR
entire valve is thickened and prolapsing
excess leaflet tissue
Chordae are elongated
Papillary muscles maybe elongated
Annulus is dilated and occasionally calcified
Generalized myxomatous degeneration


What are indications for tricuspid valve annuloplasty when performing left sided sirgery

Severe TR (functional)
Tricuspid annulus dilation > 40mm


When do asymptomatic pts with MR usually develop symptoms

5-10 years after diagnosis
High event rates were seen when quantitatively graded severe degenerative MR (EROA >40mm2) occurs.


What are difference between European and North American Guidelines for mitral valve surgery

Europeans recommend surgery with LVESD > 45mm
North American recommend surgery with LVESD > 40mm


Why even bother with asymptomatic mitral valve surgery

Rosenhek--132 pts with severe asymptomatic in 8 year period 45% had cardiac event
Kang et al. 161 pts showed that 99% of pts who underwent surgery and 85% of pts who were watched were cardiac event free at 9 years
Montant in 67 pts 10 year survival was significantly lower in conservative vs those operated


What are predictors of severe MR in pts who are asymptomatic

High levels of brain natriuretic peptide (>105)) were assoicated with unfavourable outcomes

LVESD >40mm is independently associated with increased mortality under medical management and after surgery

Suri and collegues at mayo showed that ejection fraction of >65% is associated with superior recovery of left ventricular function


Atrial fibrillation and Systolic pulmonary pressure at rest of > 50mmhg are what class of indication for mitral valve repair

Class IIa


What is current indication for minimally invasive mitral valve repair

Class IIb


What are potential benefits of minimally invasive

Reduced sternal complication
reduced blood transfusion
reduced atrial fibrillation
reduced ventilation times
reduced ICU length of stay
reduced hospital length of stay
improved cosmesis


What are potential negatives of minimally invasive mitral valve repair

increased risk of stroke
increase risk of aortic dissection
prolonged cross clamp, cardiopulmonary bypass and procedure time


What are the comparable outcomes for minimally invasive and traditional approach to mitral valve repair

comparable short and long term mortality


What are contraindications to minimally invasive access

Severe calcification of annulus
Severe lung pathology (adhesions)
small peripheral vessels


List additional surgical options for Functional MR

2 size downsizing restricted annuloplaty (sized for a 30 so you place a 26)
string and a ring concept
secondary chordal cutting
posterior leaflet extension
septal-lateral banding
posterior LV wall plication
PPM relocation-(Dr. Kron)


What is data for cutting secondary chords in Ischemic MR

In 2007 they found a reduced frequency of early recurrence (15% vs 37%) of ischemic MR by adding this technique


List contraindications to balloon vavotomy

Heavily calcified valve
MS with more then mild MR
Nodular calcifications of both commissures
MV obstruction without commissural fusion


List contraindications to percutaneous balloon mitral valvotomy based on echo

Moderate to severe MR
Mild MS
Presence of LA thrombus
Calcified and non-pliable valve (low risk surgical candidates)


List rare cases of double valve disease

Ergotamine toxicity
Radiation injury
Blunt trauma
Relapsing polychondritis
Ectodermal anhydrotic dysplasia
Werner syndrome
Maroteaux-Lamy syndrome


What papillary muscle is more likely prone to ischemia

posterior medial papillary muscle is more likely because it is supplied by just the PDA
in 63% of cases

The Anterior lateral papillary muscle is supplied by LAD and circumflex


When does papillary muscle rupture occur

usually occurs 2 to 7 days after MI.

without urgent surgery, approximately 50 to 75% die in 24 hours


List genes associated with mitral valve prolapse

3 different Loci-Chromosomes 16, 11, and 13 (automomial dominant) are linked to mitral valve prolapse.


What is X-linked myxomatous mitral dystrophy

Locus on chromosome X cosegrates a rare form of mitral valve prolapse

Some degree of mitral prolapse is seen in 5 to 6% of the female population


What are the outcome of mitral valve PPM

Independently associated with persisting pulmonary hypertension
increased incidence of CHF
reduced survival


What are Guidelines on reporting morbidity on prosthetic valves

Structural valve deteriorgation
Non Structural valve degenerations
Valve thrombosis
Bleeding event
Operated Valve endocarditis


List 5 predictors of recurrent MR post ischemic MR repair

Posterior leaflet angle >45
Anterior leaflet angle >25
Tenting area >2,5 cm2
Coaptation distance >10mm
End systolic interpapillary muscle distance >20mm
Systolic shericity index >7


What are ways to distinguish post MI VSD with papillary muscle rupture

1. murmur of septal rupture is more prominent @ the left sternal border and is louder and associated with a thrill.
2. murmur of pap muscle rupture is best heard at apex and is softer with no thrill.
3. VSD rupture is most likely associated with anterior infarction and conduction abnormality while a pap muscle is likely posterior with no conduction

***bonus criteria**
septal rupture show > 9% step up in oxygen saturation between RA and PA
papillary muscle shows classic V waves in the pulmonary artery wedge tracing


What are rates of recurrent MR after ring annuloplasty post IMR repair

Conventional ring annuloplasty is prone to failure in these patients, with recurrent severe MR in 25% of patients as early as 1 year after surgery


List available mitral valve prosthesis

St. Jude Medical Epic
Medtronic Mosaic
Carpentier Edwards
Carptentier Edwards Magna
Sorin Mitroflow
Medtronic Hancock II


What is operative mortality for Mitral Valve Surgery in degenerative disease

A. Replacement
B. Repair

b. <1% for mitral repair


What is Operative mortality for Mitral valve surgery in IMR for repair or replacement

range 4 to 30%


List type of chordae

a. First Order: Originate near the papillary muscle tips and insert on the leading edge of the leaflets
b. Secondary/Strut: originate in same location, thicker, few in the number, insert on the ventricular side of the leaflets. most important in ventricular function
c. Third order: originate directly from ventricular wall, fan shaped.


What is pathophysiology of Rheumatic fever

Group A beta-hemolytic strep
antigens cross-react with human tissues "molecular mimicry" and stimulate immune response.
This mimicry on heart tissue proteins, combined with inflammatory cytokines, and low IL-4 production leads to autoimmun reactions and damage.

mitral most common (40%)


What is pathoanatomical features of mitral RF

commisural fusion
leaflet fibrosis with stiffening and retraction
chordal fusion and shortening


List all components of valvular-ventricular complex

Mitral annulus
Chordae tendineae
Papillary muscles
left atrium
left ventricle


How often does IMR occur

40% of pts in heart failure
15% of pts with acute MI in anterior territory
40% of pts with acute MI in posterior territory


What is physiology of mitral annular calcification

pts older 60, women > men
Stress-induced feature
associated with systemic HTN, hypertrophic cardiomyopathy, aortic stenosis, and occasionally Barlows.
Chronic renal failure, DM, and advanced AS are associated features


What occurs with mitral valve replacement when the chords ARE divided

a. no post operative change in LVEDV
b. increase in LVESV
c. increases in LV end-systolic stress
d. Decrease in LV ejection fraction


What occurs in mitral valve sparing chordal replacement (chords are SAVED)

Smaller LVEDV and smaller LVESV
Decreased LV ESS (systolic stress)
unchanged ejection fraction

A smaller chamber size, reduced systolic after load, and preservation of contractile function act in concert to maintain ejection fraction.

increased chamber size, increased systolic afterload and reduction in contraction around papillary muscles may be the reasons why chordal division outcomes are worse


List two ways to measure the annuluplasty ring

Height of the anterior leaflet
Inter-trigonal distance


What is the durability of the prosthetic mitral valves?

Much less then aortic position
Maybe b/c of higher ventricular systolic pressures against the mitral cusps compared to the diastolic pressured resisted by the aortic cuspus.
directly related to age, hyperca+, chronic renal.


What are rates of Freedom from SVD after mitral replacement with Bioprosthesis

5 years = 98%
1- years= 70-85%
15 years = 50%
20 years = minimal data


What is survival at 10 years for mitral valve replacement for bioprosthetic valve?

about 50-60%


List some predictors of mortality after mitral valve surgery

Overall age
New York Heart association III or IV
presence of CAD
ventricular dysfunction
Pre-existing pulmonary hypertension
prosthesis type


List predisposing factors for Infective endocarditis in mitral position

rheumatic valvular disease
intravenous drug abuse
degenerative valve disease
intravascular prosthesis and devices
hemodialysis catheters
nosocomial infections


What is patholophysiology of IE and locations in mitral position

NVE---endocardial trauma resulting in alteration of valvular endocardial surface---deposition of fibrin and platelets with attachment of bacteria

Usual site on mitral valve is at the base of the atrial aspect of the leafets/ Annular or subannular invasion can cause separation at the AV junction.

Occasionally "drop lesion" from Aortic valve land on anteior mitral leaflet or the tensor apparatus of the mitral valve.


What are differences in prevalence of IE for mitral and aortic

For NVE mitral valve more likely to get infected then aortic.
for PVE it is more common for aortic then the mitral
risk is greatest 5 weeks post surgery then declines
< 1 year is early and > 1 year is late
incidence of early is 1% and 0.5 to 1%/year is late


What are most common pathogens

Endocarditis of native valves is most likely Streptococcus viridans


List the HACEK organisms

Cardiobacterium hominis
Eikennal corrrodens

account for 3% of culture negative PVE

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