The development of septation in the four-chambered heart.
Level 5 - mechanism / opinion, no new human data
Narrative review and descriptive animal developmental imaging without clinical data
PubMed 24863187 · doi:10.1002/ar.22949
What was done
The authors reviewed structural changes during cardiac chamber septation using episcopic microscopy and scanning electron microscopy images in mouse embryos, describing anatomical sequences from embryonic day 10.5 onward to correlate with human congenital septal defects.
What was found
The abstract reports purely descriptive morphological pathways with no numerical data. Cardiac septation in mice begins at embryonic day 10.5 with primary atrial septum growth toward atrioventricular cushions. Cranial attachment breakdown generates the secondary foramen as the mesenchymal cap fuses with endocardial cushions. Muscularization of the cap and mediastinal protrusion forms the definitive atrial septum base. The ventricular septum develops via apical muscular ballooning, with the membranous septum arising from atrioventricular cushions and muscularizing outflow cushions forming the subpulmonary infundibulum.
Why it matters
Establishing precise anatomical steps in chamber septation clarifies the developmental origins and phenotypic variations of atrial and ventricular septal defects.
Limits
No quantitative data, sample sizes, or statistical metrics are reported. Findings are based on descriptive mouse imaging rather than direct human developmental or clinical cohorts.
Cited by
- supports The human heart consists of four chambers, with two atria on the top and two ventricles on the bottom.