Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

10. Congenital Heart dz > MVD > Flashcards

MVD Flashcards

1
Q

Embryology

A
  • Fusion of inferior and superior endocardial cushion → from R and L AV junctions
  • Endocardial cushion on L side forms anterior MV leaflet + L and non-coronary cusps → fibrous continuity
  • Protusion/growth of AV mural endocardium: mural leaflet
    o Formation of valvar mesenchyme
    o Apoptosis of myocardial layer
  • Papillary muscle: columns in trabecular layers of ventricular muscle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Gross exam MVD

A
  • Abnormal MV leaflets
    o Rolling, notching
    o Short and thick leaflets
    o Cleft leaflets
    o Leaflet adhered to septum
  • Fusion/thickening or elongation of chordae tendinae
    o Short and stout chordae
    o Long and thin
  • Upward malposition of pap muscles → horizontal chordal alignment
    o Atrophied (flat and small) or hypertrophied
    o Direct insertion of leaflet into pap muscle
    o Fusion and displacement
  • Diffuse endocardial fibrosis of LA is common finding
  • Concurrent malformation: SAS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Pathophys MVD

A
  • Inadequate leaflet coaptation → MR
    o L sided volume overload → LAE/LVE
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

MVD signalment

A

o Mostly large breed dogs: genetic basis suspected
 Bull terrier
 Great Dane
 German Shepherd
o Most common CHD in cats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

MVD PE

A

o Holosystolic plateau murmur over L apex
o Systolic click if prolapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

ECG MVD

A
  • L sided cardiomegaly:
    o LV = tall R waves
    o LA = prolonged P waves
  • Atrial arrhythmias 2nd to LAE → Afib
  • Ventricular pre excitation from anomalous atrioventricular pathway reported in dogs/cats
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

CTX MVD

A
  • L sided cardiomegaly
  • +/- pulmonary edema
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

2D echo MVD

A
  • ↑ LV end diastolic diameter, normal wall thickness
  • LAE
  • MV: abnormal location, shape, motion, attachment of valve apparatus
    o Large MV annulus
  • LV function is variable, may deteriorate w time
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Doppler echo MVD

A

o Large MR
o LVOTO reported in cats 2nd to SAM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Differentiation MR MVD from MR DCM

A
  • Large MR jet
  • Loud HM
  • FS >20%
  • Normal to ↑ IVS motion vs LVFW
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Cardiac KT angio MVD

A

o LV injection of contrast → confirm MR in LA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Cardiac KT pressure study MVD

A

o ↑ LV end diastolic P if CHF
o ↑ mean LAP and
o LA: ↑a wave, large v wave, low of x descent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Natural hx MVD

A
  • Generally tolerated for many years
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Treatment MVD

A

o CHF
o B blockers if LVOTO
o MV repair

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

MVS gross exam

A
  • Diffuse abnormalities of valve components
    o Thickened/rolled leaflet margins
    o Shortened/thickened chordae tendinea
    o Fibrous obliteration of interchondral spaces
     Excessive valvular tissue
    o Abnormal chordal insertion
    o Pap muscle hypoplasia, ↓ inter pap distance/fusion
  • Annular hypoplasia
  • Commissural fusion
    o Restriction of MV motion
    o Narrowed central orifice
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Common associated defect MVS

A
  • SAS: can be present from
    o Redundant MV leaflet tissue in LVOT
    o Anomalous MV leaflet/chordal attachment to IVS → DLVOTO
17
Q

Other types of MVD

A
  • Double orifice MV
  • Mitral arcade = hammock valve
  • Parachute MV (asymmetric)
  • Cleft MV
  • Straddling MV
18
Q

Double orifice MV

A

o Accessory bridge or tissue → partially/completely dived mitral inlet into 2 orifices
 Unequal, smaller orifice toward anterolateral or posteromedial commissure
o Usually associated w other congenital dz

19
Q

Mitral arcade

A

hammock valve

o Thickened MV leaflets, inserting directly into LV wall or pap muscle
o Absent/short chordae: muscularization of chordal apparatus
o Band of fibrous tissue: free margin of valve leaflets → pap muscle

20
Q

Parachute MV

A

o Unbalanced chordal attachment to single pap muscle (single or dominant pap muscle)
 Short and thick chordae
 Variable pap muscle anatomy: absent, fused, single
o Absent of fused commissures
o Centrally located orifice above single pap muscle

21
Q

Cleft MV

A

complete or tip only

22
Q

Straddling MV types

A

o Type A: crest of IVS
o Type B: septal pap muscle of RV
o Type C: mural pap muscle of RV → ↑ override

23
Q

Other defects w/ inlet obstruction

A
  • Cor triatriatum sinister: abn insertion of PV into LA → obstruction of PV return
    o LAA in DISTAL chamber
  • Coronary sinus obstruction
    o w/ persistent LCrVC
  • Supravalvular mitral stenosis: ring of fibrous tissue above MV
    o LAA in PROXIMAL chamber
    o Male cats/Siamese overrepresented
  • MV atresia/hypoplasia: hypoplasia of all components of apparatus
24
Q

MVS histo

A
  • Fibrous tissue
  • Myxoid dysplasia
25
Q

Pathophys MVS

A
  • Narrowed MV orifice → ↑ resistance to blood flow from LA → LV in diastole
    o PG across MV
    o ↑ LAP → ↑ PV and pulmonary capillary pressures → pulmonary edema
26
Q

MVS c/s

A

L-CHF
o Syncope: ↓ LV SV

27
Q

MVS PE

A

o Mid diastolic L apical heart murmur
o Accentuated S1

28
Q

ECG MVS

A
  • P wave prolongation
  • APC
  • SVT, Afib
29
Q

CTX MVS

A
  • LAE: double density sign, dorsal tracheal deviation
30
Q

Echo 2D MVS

A

o Abnormal MV motion
 ↓ diastolic MV excursion
 Leaflet doming toward LV in diastole
 Thickened MV leaflets
o LAE
o LV: normal, ↓ or ↑ in size depending on amount of MR

31
Q

M-mode echo MVS

A

o ↓MV motion, ↑MV opening time
o ↓EF slope

32
Q

Doppler echo MVS

A

o Turbulent, aliased flow across MV
o Restrictive LV filling pattern
 ↓ peak E wave
 Prolonged deceleration time of E wave
 ↑ A wave
o ↑ transvalvular PG
 Mild 8-10mmHg
 Moderate 11-15mmHg
 Severe >15mmHg
* ↑ pressure ½ time

33
Q

Cardiac KT MVS pressure study

A

o ↑ PAP and PCWP
o LAP: ↑ a wave
o Diastolic PG btw LA and LV

34
Q

Cardiac KT angio MVS

A

hourglass shaped diastolic filling defect

35
Q

Pathophys MVS

A
  • Resistance to blood flow from LA → LV through narrowed MV orifice during diastole
    o ↑LAP and pulmonary capillary pressures
    o Severe disease → CHF
36
Q

Clinical functional classification MVS

A

o Symmetric:
 Normal chord distribution from each leaflet to pap muscle
 Variable annular + leaflet hypoplasia
* Thick leaflets w restrictive motion/commissural fusion
* ↓ interpapillary muscle distance
* Obliterated interchordal spaces
* Centrally oriented valve orifice, smaller than annular
o Asymmetric: unbalanced chordal attachment

37
Q

Tx MVS

A

o CHF: avoid excessive diuresis → ↓ preload since can ↓ LV filling from ↓ PG
o Surgery:
 Commissurotomy, MV replacement
 Balloon: risk of MR

10. Congenital Heart dz (28 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions