A magnetic field can exert a magnetic force on a wire if the wire is carrying a current. (F=BIL). This is the basis for all electric motors.
Here is a home-made toy DC motor: It works despite having no commutator. How come?
2 segments of the wire must be experiencing magnetic forces in opposite directions, in order for the heart to spin. Can you identify the segments?
This motor is rotated by one single torque (instead of a couple). Can you figure out how it works?