Three-dimensional spectral map of atrial fibrillation by a 64-channel magnetocardiogram

We verified the significance of 3-dimensional (3D) spectral mapping during atrial fibrillation (AFIB) using a 64-channel magnetocardiogram (MCG). The study consisted of 16 patients with valvular heart disease who had chronic AFIB. All 16 patients had surgical pulmonary vein (PV) isolation followed by valvular repair. We performed spectral mapping by fast Fourier transform analysis in nonaveraged 64-channel MCG data. The 3D spectral map was superimposed on a 3D heart polygon. At 1 year after surgical PV isolation for AFIB, followed by valve repair, 7 patients had restoration to sinus rhythm, and 9 patients remained in persistent AFIB. The preoperative mean 3D frequency of AFIB was 6.1 ± 0.9 Hz in patients with restored sinus rhythm and 7.2 ± 0.7 Hz in patients with sustained AFIB after PV isolation (P = .02). In addition, the preoperative 3D spectrum was distributed on the right side of the heart in patients with persistent AFIB. In conclusion, 3D spectral mapping using 64-channel MCG may represent a meaningful noninvasive strategy for patients with AFIB who receive an interventional procedure.