heart left atrium morphological measurement heart left atrium end-diastolic diameter 2013-01-25T15:50:33Z CMO:0001486 JSmith The distance between two specified opposite points on the periphery of the left atrium of the heart at the end of diastole, that is, when the left ventricle is maximally dilated, and usually corresponds to the left atrium's smallest diameter. VT:0010493 clinical_measurement_ontology