Subset of cells in the primordial tube-like heart that is essential to the development of the ventricular septum and the atrioventricular valves of the heart.
Note: Endocardial cushion defects may cause various types of heart
malformation.
Source:
PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 748 (https://doi.org/10.1515/pac-2015-1202)