Validation of high temporal resolution spiral phase velocity mapping of coronary artery blood flow against Doppler flow wire

Background The temporal pattern of coronary artery flow velocity through the cardiac cycle provides important information about coronary haemodynamics. The ‘gold standard’ for coronary artery velocity assessment is the Doppler flow wire which is inserted directly into the coronary artery under X-ray fluoroscopic guidance, which is invasive, uses ionising radiation and has a small but significant risk of serious complication. In this study, we perform an in vivo comparison of coronary blood flow velocities measured with breath-hold high temporal resolution spiral phase velocity mapping and Doppler flow wire measurements.