Figure 3. Stages in FIRM mapping. Right atrium basket is opened vertically on tricuspid valve and left atrium is opened horizontally along mitral valve. A) Rotor in left atrium visualized with isochrones. B) Clockwise rotation and precession of rotor over a small locus. C) Phase plot of same rotor showing convergence of phase at rotor core. D) Snapshot from FIRM movie depicting phase and direction of rotor in red. From.[36].
