heart ventricle septal wall thickness heart interventricular end-systolic septal wall thickness heart interventricular end-systolic wall thickness 2018-05-15T17:13:43Z jrsmith heart interventricular septum end-systolic thickness IVSs The thickness, width or depth of the septal wall of the heart ventricles (that is, the portion of the wall between the left and right ventricles that is shared between the two) at the end of systole when the heart muscle is maximally contracted. clinical_measurement_ontology CMO:0002792