The outflow tract of the heart — embryologic and morphologic correlations

doi:10.1016/0167-5273(89)90270-2

International Journal of Cardiology

Volume 22, Issue 3, March 1989, Pages 289-300

https://doi.org/10.1016/0167-5273(89)90270-2 Get rights and content

Abstract

The separation process of the heart by which two great arteries and two outflow tracts are formed, was studied microscopically in 20 human embryos, ranging from 6 to 28 mm crown-rump length and macroscopically in eight hearts, ranging from 28 weeks of gestation to 80 years of age.

The proximal (primary fold) and distal (ventriculo-arterial junction) borderlines of the outlet segment of the embryonic heart are important landmarks in this process. The remarkable, curved and twisted configuration of the ventriculo-arterial junction implies that the position of the arterial orifices, as well as the relative dimensions of the corresponding outflow tracts, are, already in a very aerly stage, similar to those in the fully developed heart. It furthermore implies that the separation by the aorto-pulmonary septum starts at this level and immediately involves the outlet segment where the two columns of the aorto-pulmonary septum mobilize the myocardium to form the posterior wall of the right vertricular outflow tract, rather than a septum between both outflow tracts.

These findings make the morphology of the outflow tract of the normal heart comprehensible from a developmental point of view and throw a new light upon the morphogenesis of outflow tract malformations.

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^☆: This study was supported by the Dutch Heart Foundation

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ReviewThe outflow tract of the heart — embryologic and morphologic correlations☆

Abstract

Am J Cardiol

Am J Cardiol

Am J Cardiol

Int J Cardiol

Int J Cardiol

Int J Cardiol

Am J Cardiol

J Thorac Cardiovasc Surg

Anatomy of double outlet right ventricle

The spectrum of transposition of the great arteries. With special reference to developmental anatomy of the conus

Circulation

Contribution of the aortopulmonary septum to the muscular outlet septum in the human heart

Acta Morphol Neerl-Scand

The arterial orifice level in the early human embryo

Anat Embryol

Development of the outflow tract and closure of the interventricular septum

Am J Anat

Graphic reconstructions and stereoscopy

J Audiov Media

Die Plattenmodelliermethode

Arch Mikros Anat

Embryology of the heart

Left and right trabecular patterns. Consequence of ventricular septation and valve development

Br Heart J

Anatomic considerations

Review
The outflow tract of the heart — embryologic and morphologic correlations☆