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8662952020
Mitral Valve Surgery

Understanding the Valve and Dynamics and Pathology

Cordae

The chordae tendineae connect the mitral valve to the papillary muscles within the ventricles[2]. Multiple chordae tendineae attach to each leaflet or cusp of the mitral valve[2]. According to a study of 50 normal mitral valves, there are different types of chordae tendineae[1][3][6]:

  • Simple un-branched chordae (Type 1): present in 19.82% of the mitral valves studied[3].
  • Spiral or dichotomous branching chordae (Type 3): seen in 80% of the mitral valves studied[3].
  • Fan-shaped chords (Primary, Secondary, and Tertiary): running from the papillary muscles and inserting into the leaflets[6]. Primary chords attach to the free edge of both leaflets, secondary chords attach to the ventricular surface in the region of the rough zone, and tertiary chords are found in the mural (posterior) leaflet only which has a basal zone[6].

However, none of the sources provide a specific number of chordae tendineae in a normal mitral valve.

Citations:
[1] https://www.ahajournals.org/doi/pdf/10.1161/01.CIR.41.3.449?download=true
[2] https://en.wikipedia.org/wiki/Chordae_tendineae
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4379635/
[4] https://emedicine.medscape.com/article/1878301-overview
[5] https://www.sciencedirect.com/topics/neuroscience/chordae-tendineae
[6] https://academic.oup.com/ehjcimaging/article/11/10/i3/2397001

Papillary muscles

There are five papillary muscles in the heart, three in the right ventricle and two in the left ventricle[1][5]. The anterior, posterior, and septal papillary muscles of the right ventricle each attach via chordae tendineae to the tricuspid valve, while the anterolateral and posteromedial papillary muscles of the left ventricle attach via chordae tendineae to the mitral valve[1][2][5].

Citations:
[1] https://www.ncbi.nlm.nih.gov/books/NBK499976/
[2] https://www.mitralvalverepair.org/papillary-muscles-and-left-ventricle
[3] https://www.jtcvs.org/article/S0022-5223(17)33036-2/pdf
[4] https://www.ncbi.nlm.nih.gov/books/NBK557802/
[5] https://en.wikipedia.org/wiki/Papillary_muscle
[6] https://www.sciencedirect.com/topics/medicine-and-dentistry/papillary-muscle