Are pacemakers affected by magnetic field cancelling?

In normal use, a magnetic field cancelling system does not affect a pacemaker.

The level of field that affects a pacemaker is several orders of magnitude higher than the level of field that affects an electron microscope. Our systems actually reduce the levels of field at the microscope and make changes to the levels of field of the same order of magnitude as the pre-existing ambient field in other parts of the room. The only place our systems make stronger fields is right next to the cancelling cables. Therefore it would be inadvisable to press your pacemaker right up to a cancelling cable.