abnormal interventricular septum membranous part morphology interventricular septum membranous part aneurysm MP:0010416 2010-09-27T03:54:46Z csmith MPheno.ontology Fyler:2346 a a saclike thinning, stretching and widening of the ventricular membranous septum resulting from weakening of the membraneous septum wall aneurysm of membranous septum ventricular membranous septum aneurysm ventricular aneurysm