Multifractal analysis for grading complex fractionated electrograms in atrial fibrillation

Area of Science:

• Cardiology
• Biomedical Engineering
• Signal Processing

Background:

• Complex fractionated atrial electrograms are crucial for identifying arrhythmogenic substrates in atrial fibrillation (AF).
• The phenomenon of electrogram fractionation in AF remains poorly understood.
• Current methods for analyzing fractionation may lack discriminatory power.

Purpose of the Study:

• To evaluate the multifractal properties of electrograms in AF.
• To propose a novel method, the h-fluctuation index (hFI), based on multifractal analysis to discriminate between different levels of fractionation.
• To assess the utility of hFI in guiding catheter ablation for AF.

Main Methods:

• Utilized two multifractal frameworks: multifractal detrended fluctuation analysis and wavelet transform modulus maxima.
• Introduced the h-fluctuation index (hFI), derived from the generalized Hurst exponent, to analyze the multifractal spectrum shape.
• Validated hFI on synthetic signals and a database of AF electrograms categorized by four degrees of fractionation.

Main Results:

• The h-fluctuation index (hFI) demonstrated superior performance in grading fractionation compared to other existing indexes.
• Multifractal analysis proved effective in characterizing fractionation phenomena in AF electrograms.
• hFI successfully discriminated between different levels of electrogram fractionation.

Conclusions:

• Multifractal analysis is a valuable tool for studying fractionation in AF electrograms.
• The h-fluctuation index (hFI) shows promise as a quantitative method for grading fractionation.
• hFI can aid in identifying target sites for catheter ablation in AF patients.