Processing of intracardiac electrograms in atrial fibrillation

This paper presents a method for the automated processing of atrial fibrillation (AF) electrograms for the diagnosis of the electropathological substrate of AF and to monitor the effects of ablation procedures and anti-arrhythmic drug treatment on the characteristics of AF. Template matching is a well-known signal processing technique that has been proven useful in various other applications like processing of medical images and fingerprint verification. One of the advantages of this technique is that, because the involved calculations are not very complex, it can easily be applied in real time by using digital hardware. All it requires is the acquisition of fibrillation electrograms, analog-to-digital conversion, and a template matching algorithm downloaded in state-of-the-art digital signal processors. This will provide an objective characterization of fibrillation electrograms that in case of recording of multiple electrograms will produce real-time movies of the propagation of fibrillation waves through the atria. This will allow real-time identification of areas with preferential intra-atrial conduction block, rotor activity, or a focal spread of activation. The further development of algorithms for automatic analysis of fibrillation electrograms, therefore, is not only of scientific interest but may also allow individual evaluation of the atrial substrate, thus providing a basis for selecting the most appropriate treatment of AF