Christian Binter1, Verena Knobloch1, Robert Manka1, 2, Andreas Sigfridsson1, Sebastian Kozerke1
1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland; 2Cardiac Imaging, University Hospital Zurich, Zurich, Switzerland
Aortic valve performance is typically assessed by means of pressure gradients or orifice sizes, which correlate only weakly with the energy loss across the valve. Here a method to directly determine the energy budget of the flow is presented. Using generalized phase-contrast flow measurements with multiple velocity encodings the energy loss due to turbulence and regurgitation can be quantified. By relating these losses to the available kinetic energy of the flow, a parameter for the efficiency of heart valves can be obtained. It is shown that significant differences in energy efficiency between different valve designs and between heart valve patients and healthy controls exist.