Phase mapping with a Moving Average dynamic cycle length algorithm highlights rotors but can generate false rotors, making combined time-domain activation and phase mapping the most reliable method.
Observational (n=7)
Does phase mapping with MVG-DCL improve the detection of rotors in human cardiac arrhythmias compared to traditional methods?
A combined approach of time-domain activation and phase mapping with variable cycle length is recommended to prevent misinterpretation and false rotor detection in complex arrhythmias.
BACKGROUND: Phase analysis of cardiac arrhythmias, particularly atrial fibrillation, has gained interest because of the ability to detect organized stable drivers (rotors) and target them for therapy. However, the lack of methodology details in publications on the topic has resulted in ongoing debate over the phase mapping technique. By comparing phase maps and activation maps, we examined advantages and limitations of phase mapping. METHODS AND RESULTS: Seven subjects were enrolled. We generated phase maps and activation maps from electrocardiographic imaging-reconstructed epicardial unipolar electrograms. For ventricular signals, phase was computed with (1) pseudoempirical mode decomposition detrending and (2) a novel Moving Average (MVG) detrending approach. For atrial fibrillation signals, MVG was modified to incorporate dynamic cycle length (DCL) changes (MVG-DCL). Phase maps were visually analyzed to study phase singularity points and rotors. Results show that phase is sensitive to cycle length choice, a limitation that was addressed by the MVG-DCL algorithm. MVG-DCL was optimal for atrial fibrillation analysis. Phase maps helped to highlight high-curvature wavefronts and rotors. However, for some activation patterns, phase generated nonrotational singularity points and false rotors. CONCLUSIONS: Phase mapping computes singularity points and visually highlights rotors. As such, it can help to provide a clearer picture of the spatiotemporal activation characteristics during atrial fibrillation. However, it is advisable to incorporate electrogram characteristics and the time-domain activation sequence in the analysis, to prevent misinterpretation and false rotor detection. Therefore, for mapping complex arrhythmias, a combined time-domain activation and phase mapping with variable cycle length seems to be the most reliable method.
Vijayakumar et al. (Tue,) conducted a observational in Cardiac arrhythmias (atrial fibrillation) (n=7). Phase mapping with Moving Average dynamic cycle length (MVG-DCL) vs. Activation maps and pseudoempirical mode decomposition was evaluated on Phase singularity points and rotors. Phase mapping with a Moving Average dynamic cycle length algorithm highlights rotors but can generate false rotors, making combined time-domain activation and phase mapping the most reliable method.