Morphogenesis of chordae tendineae. I: Scanning electron microscopy
The Anatomical Record
|December 1, 1984
Summary
The development of chick embryo heart valves involves the formation of chordae tendineae from primitive papillary muscles and web-like folds. These structures support valve cusps through a process of perforation and consolidation.
Area of Science:
- Developmental Biology
- Cardiovascular Science
- Embryology
Background:
- The chordae tendineae are crucial supportive structures for atrioventricular valves.
- Understanding their formation is key to comprehending heart development.
Purpose of the Study:
- To describe the formation of chordae tendineae in the chick embryo heart.
- To elucidate the cellular and morphological processes involved in their development.
Main Methods:
- Scanning electron microscopy was utilized to visualize the developing structures.
- Observations spanned from day 6 to day 13 of incubation.
Main Results:
- Chordae tendineae originate from ventricular wall elevations (primitive papillary muscles) that bifurcate into folds.
- Perforation of linear ridges on these folds creates individual chordae, with consolidation of multiple perforations.
- Prominent rounded endocardial cells are observed during perforation, similar to those in atrial septum formation.
- Second-order chordae are most abundant, inserting into the cusp surface, while first-order chordae are absent.
Conclusions:
- Chordal development in chick embryos is a complex process involving programmed cellular activity and hemodynamic forces.
- The described mechanism provides insight into valvular heart structure formation.
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