Determining exercise-induced blood flow reserve in lower extremities using phase contrast MRI

Academic Article

Abstract

  • Purpose: To study the changes in limb blood flow during lower extremity exercise using phase contrast (PC) MRI in normal volunteers. Materials and Methods: Healthy volunteers performed plantar flexion exercise (<1 W) for four minutes. Flow velocity was measured using cardiac-gated, cine PC-MRI sequences (fast gradient recalled echo [GRE]; multishot echo planar imaging [EPI]) on a 3T scanner at the level of the superficial femoral artery (SFA): 1) preexercise: 2) immediately postexercise; 3) during three minutes recovery; and 4) postrecovery. Results: At rest there was a triphasic flow waveform in the SFA. During exercise it changed to a monophasic pattern with an increase in total flow; there were variable changes in vessel size and flow velocity. The waveform regained the triphasic pattern during recovery. The exercise-induced flow reserve (FR) was 167 ± 90%. Conclusion: PC-MRI demonstrates that the resting triphasic flow waveform transforms into a monophasic pattern with submaximal exercise and returns to baseline with recovery. This increase in the regional blood flow allows for measurement of exercise-induced FR in the SFA. © 2008 Wiley-Liss, Inc.
  • Authors

    Published In

    Digital Object Identifier (doi)

    Author List

  • Nagaraj HM; Pednekar A; Corros C; Gupta H; Lloyd SG
  • Start Page

  • 1096
  • End Page

  • 1102
  • Volume

  • 27
  • Issue

  • 5