trabecula carnea hypoplasia MP:0000295 MPheno.ontology decrease in the number of normal cells in normal arrangement in the supporting bundles of muscular fibers lining the walls of the ventricles of the heart, typically resulting in decreased size hypoplastic trabecula carnea poorly developed trabecula carnea poorly developed ventricular trabeculae abnormal trabecula carnea morphology ventricle myocardium hypoplasia myocardial trabeculae hypoplasia trabecula carnea hypoplasia