June Cheng-Baron1, Jessica M. Scott2, Ben T. Esch2, Mark J. Haykowsky2, John V. Tyberg3, Richard B. Thompson1
1Biomedical Engineering, University of Alberta, Edmonton, AB, Canada; 2Physical Therapy, University of Alberta, Edmonton, AB, Canada; 3Cardiac Sciences, University of Calgary, Calgary, AB, Canada
It has been shown that blood velocity waveforms measured at the conventional mitral leaflet tips location do not match mitral flow waveforms. In this study we quantify the relationship between velocity profiles at several points along the inflow path and volumetric flow, illustrating the dependence of commonly derived diastolic parameters (E/A ratio, deceleration time) on the measurement approach. Velocity profiles and derived parameters vary significantly over small (1 cm) intervals and are distinct from flow profiles. Velocity-time curves above the conventional leaflet tip location (in the atrium) are less susceptible to measurement error and are most similar to flow curves.