Quantification of thoracic aorta blood flow by magnetic resonance imaging during supine cycling exercise of increasing intensity

Background Cardiac magnetic resonance imaging (MRI) may be used for the diagnosis and follow-up of diseases affecting the thoracic aorta (TA). Typically, patients are imaged at rest. Quantifying TA blood flow distribution during activity may improve understanding of disease impact by assessing possible factors contributing to exercise intolerance. Blood flow quantification during exercise MRI, though, has heretofore been complicated by prolonged MRI scan times, motion artifact, and gradient field inhomogeneities. We developed a protocol for phase-contrast (PC) MRI flow quantification in the TA and head and neck arteries during three-tiered supine cycling submaximal exercise.