3D respiratory resolved phase contrast imaging of the aorta

Background Respiratory motion compensation is essential for reproducible and robust cardiovascular MRI. Traditionally, breathholds or prospective gating by bellows or navigator signals limit data acquisition to the quiescent phase of respiration [1]. These approaches do not capture any variations of blood flow over the respiratory cycle, yet respiration has been shown to significantly affect flow in the great vessels [2]. The purpose of this pilot study was to adapt a 3D radially undersampled PC MR sequence (PC VIPR [3,4]) for use with our retrospective dual-gated (cardiac and respiratory) reconstruction to evaluate respiratory effects on net flow and cardiac flow waveforms.