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Updated: Aug 9, 2026

Murine Fetal Echocardiography
Published on: February 15, 2013
Development of the pars membranacea septi interventricularis of the human heart. II. Thickness change
R R Figueira1, J C Prates, H Hayashi
1Department of Morphology, Escola Paulista de Medicina, São Paulo, Brazil.
Abstract:
The measurement of the thickness of the pars membranacea septi interventricularis of the human heart increases with the intra-uterine age of the fetus along a steep, ascending, straight line. The thickening of the PMSI occurs in phase I of the development from 0.246 mm (CR = 16.8 mm) to 0.524 mm (CR = 119 mm) and in phase II from 0.601 mm (CR = 149 mm) to 1.024 mm (CR = 362 mm). The thickness increases, then, from the ending of the closure of the secondary interventricular foramen to the end of the fetal period.
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