VDM Verlag Magnetic Resonance Imaging of Cardiac Dyssynchrony: Can phase contrast velocity imaging be used to identify abnormal myocardial wall motion?

Cardiac resynchronization therapy (CRT) is a highly effective treatment for heart failure patients with dyssynchrony, but selection of patients for CRT remains problematic. The goal of this project was to develop a patient selection tool for CRT based on myocardial wall velocities acquired with Magnetic Resonance Phase Velocity Mapping (MR PVM). First the image acquisition and post-processing protocols for MR PVM imaging of myocardial tissue were developed. A myocardial motion phantom was used to verify the accuracy of, and optimize the acquisition parameters for, the developed MR PVM sequence. Excellent correlation was demonstrated between longitudinal myocardial velocity curves acquired with the optimized MR PVM sequence and Tissue Doppler velocities. A database describing the normal myocardial contraction pattern was constructed. A small group of dyssynchrony patients was compared to the normal database, and several areas of delayed contraction were identified in the patients. Finally, a method for computing transmural, endocardial, and epicardial, radial strains and strain rates from MR PVM velocity data was developed. About the Author After earning her BS in Biological and Agricultural Engineering from the University of California at Davis, Jana Delfino enrolled in the Biomedical Engineering program offered jointly by the Georgia Institute of Technology and Emory University. The work published here is her doctoral dissertation for that program.