Mitral Valve Anatomy
Mechanical and metabolic balance of the valve is maintained by
A. Endothelial cells
B. Interstitial cells
C. Endocardial cells
D. Nerve cells
Mitral annulus is thinnest at
A. Anteriorly
B. Posteriorly
C. Medially
D. Laterally
Which part of mitral valve is more vulnerable to dilatation?
A. Anteriorly
B. Posteriorly
C. Medially
D. Laterally
Which of the following are TRUE about anterior mitral leaflet?
A. Located at the anterior part of the aortic root and fixed to it
B. Located at the posterior part of the aortic root and not fixed to it
C. Located at the posterior part of the aortic root and fixed to it
D. Located at the posterior part of the aortic root and not fixed to it
In comparison to posterior leaflet, Anterior leaflet represents –
A. More annular length and Less surface area
B. More annular length and More surface area
C. Less annular length and More surface area
D. Less annular length and Less surface area
All of the following are CORRECT about anterior leaflet EXCEPT –
A. Semicircular shape
B. Free edge has indentations
C. Larger than posterior leaflet
D. Thicker than posterior leaflet
All of the following are TRUE about anterior leaflet EXCEPT –
A. One-third of the annular ring
B. Two-thirds of the valvular orifice
C. Also called Mural leaflet
D. It has two zones – rough zone and clear zone
Posterior leaflet comprises of ——– of the annular circumference
A. One-Thirds
B. Two-Thirds
C. One-Fourth
D. Three-Fourth
Which of the following only exists in the posterior leaflet and not in anterior leaflet of mitral valve –
A. Basal Zone
B. Clear Zone
C. Rough Zone
D. Basal Zone and Clear Zone
All of the following are TRUE about Primary Chordae tendinae EXCEPT –
A. Primary chordae are thicker
B. Attached to the leaflets at the free edge
C. Prevent leaflet edge to prolapse
D. Also called marginal chordae
Embryological development of Papillary muscles are formed by
A. 6th week
B. 8th week
C. 10th week
D. 12th week
Mitral valve apparatus complete development by week –
A. 12
B. 15
C. 18
D. 21
Posterior papillary muscle is supplied by-
A. RCA
B. LAD
C. Circumflex Artery
D. Major Diagonal
In shorts
Anterior leaflet
- Semicircular shape
- It has free edge without indentations
- It is larger and thicker compared with the posterior leaflet.
- It has two zones, the rough zone and clear zone that are separated by a ridge on the atrial surface.
- This prominent ridge is located 1 cm from the edge of the anterior leaflet.
- During systole – rough zone of the anterior leaflet will be adjacent to the posterior leaflet
Posterior leaflet divides into – three areas zones or segments
- Basal zones
- Clear zones
- Rough zones
Defined as P1, P2, and P3.
The rough zone is distal to the ridge and broadest at the scallops.
Mitral leaflets. The three portions of the posterior mitral leaflet, named from lateral to medial are P1, P2 and P3.
Peri-procedural imaging for transcatheter mitral valve replacement – Scientific Figure on ResearchGate. Available from: https://www.researchgate.net/figure/Mitral-leaflets-The-three-portions-of-the-posterior-mitral-leaflet-named-from-lateral_fig2_298209486 [accessed 23 Dec, 2022]
Mitral leaflets. The three portions of the posterior mitral leaflet, named from lateral to medial are P1, P2 and P3.
Multimodality imaging assessment of mitral valve anatomy in planning for mitral valve repair in secondary mitral regurgitation – Scientific Figure on ResearchGate. Available from: https://www.researchgate.net/figure/Mitral-valve-anatomy-Schematic-representation-of-the-mitral-valve-in-the-surgeon-view_fig6_318056916 [accessed 23 Dec, 2022]
What are the layers in the leaflets of the mitral valve?
Layers from the histological point of view:
| 1 | Fibrosa layer | Thick collagen fibers |
| 2 | Atrial layer | Thinner and towards the atrial surface- elastic fibers |
| 3 | Spongiosa layer | Glycosaminoglycans (GAG) and Proteoglycans. |
| 4 | Present on the ventricular side | Very thin layer of elastic fibers – Present in continuity with the elastic fabric of the chordae tendinae. |
- Fibrosa-rigid and superficial – thick collagen fibers
- Atrial- thinner and towards the atrial surface- elastic fibers
- Spongiosa- glycosaminoglycans (GAG) and proteoglycans.
- Another layer – very thin layer of elastic fibers – on the ventricular side- present in continuity with the elastic fabric of the chordae tendinae.
What are the types of Chordae tendinae?
- Primary or marginal chordae
- Secondary or intermediary chordae
Primary or marginal chordae –
- Thinner
- Attached to the leaflets at the free edge
- Preventing leaflet edge to prolapse
- Characteristic – being high collagen fibers with reduced tension.
Secondary or intermediary chordae
- Thicker than primary chordae
- More extensible due to the more tight collagen
- Secondary chordae are attached to the ventricle aspect of the leaflets
- Help to reduce tension at the leaflet
How do you classify Chordae tendinae?
Chordae tendinae can have six classifications:
| Basis of Classifications | Classifications of Chordae tendinae | |
| 1 | Depending on the origin | Apical and Basal |
| 2 | Depending on the area concerned | True or False |
| 3 | Depending on the anatomical basis | Cusp, Cleft or Commissural |
| 4 | Depending on the interest of the valve area | First-order chordae or Second-order chordae |
| 5 | Depending on the shape | Straight, Branched, Dichotomous or Irregular |
| 6 | Depending on the constitution | Tendinous, Muscular, or Membranous |
Depending on the origin – apical and basal
Depending on the area concerned – true or false
Depending on the anatomical basis – cusp, cleft and commissural
Depending on the interest of the valve area they are first-order chordae or second-order chordae
Depending on the shape – straight, branched, dichotomous or irregular
Depending on the constitution – tendinous, muscular, or membranous
Classifications of Chordae tendinae