Reproducibility of Doppler echocardiographic measurements of left ventricular diastolic function

The present investigation was undertaken in 12 normal subjectsto determine the magnitude of technical and biologic variabilityof six previously validated Doppler indexes of diastolic function.Variability due to the reader was small for each of the sixDoppler indexes. Variability due to the technician was largerthan for the reader, and day-to-day variability was larger thanvariability due to either the reader or techinician for thegreat majority of the comparisions (i.e., 21 of 24). Four Dopplerindexes assessing early diastolic events (isovolumic relaxation,duration of the early diastolic peak of flow-velocity, rateof decrease of flow-velocity in early diastole, and maximalearly diastolic flow-velocity) did not show statistically significantchanges due to day-to-day variability. The two Doppler indexesassessing late diastolic events [maximal late diastolic (atrial)flow-velocity, and the ratio between maximal early and lateflow-velocity] showed greater change on a day-to-day basis (P<0.05). In conclusion, Doppler indexes that represent a measure of isovolumicrelaxation and the early filling phases of diastole showed smallvariability. Indexes that measure the late filling phase ofdiastole, such as maximal late (atrial) diastolic flow-velocityand the ratio between early and late diastolic flow-velocities,showed relatively large day-to-day variability; therefore, serialchanges in the atrial contribution to ventircular filling identifiedby these indexes should probably be interpreted with some caution.