Feasibility of cardiac MR examination during quantitative isometric muscular exercise

MR examination during quantitative muscular exercise is currently unavailable because the MR instrument has a long gantry and exercise machines are made from ferromagnetic materials such as iron. The purpose of this study was to develop a quantitative, continuously monitored, voluntary isometric exercise device (QIED) for MR examination and to analyse the feasibility of performing MR examination using the new device.

The QIED, which consists of (1) a handgrip (rubber cuff), (2) an extension plastic tube, (3) a pressure transducer, and (4) a pressure digital display that includes the power supply. Components 1 and 2 are non-magnetic. Although components 3 and 4 are ferromagnetic, they can be set up outside the MR examination room using component 2 to prevent them from influencing the MR instrument and examination.We did not observe MR image noise or artifacts in the phantom study using the QIED. MR examination and low sensitivity 31P-MRS could be feasible during quantitative isometric exercise using the QIED.

Exercise MR examination using the QIED will provide useful information for the detailed evaluation of cardiac patients.