gms | German Medical Science

Question: Evaluation and quantification of atrial electrical remodelling is a central issue in atrial fibrillation (AF) research. Algorithms for assessment of AF cycle length (AFCL) from surface ECG have been developed. We evaluated a new commercially available ECG system with that technology for fibrillatory rate analysis in AF patients.

Method used: From September 2004 to June 2005, 48 patients (21 male; age 68±10.0 years) with permanent AF underwent 12-lead high-gain, high-resolution ECG recording (CardioLink (R), getemed AG, Teltow, Germany). After QRST cancellation fast-Fourier transformation was performed in order to identify the frequency content of the fibrillating atria. Signal quality, peak frequency component, and inter-lead as well as temporal variability of mean fibrillatory rate were investigated.

Results: Signal analysis revealed excellent quality frequency spectra in leads V1 (87% of recordings), II (78%), and V2 (70%). Spectra in V1 were characterized by unimodal peak distribution with a spectral width of 6±4.8 fibrillations per minute (fpm) and 16±10.0 fpm at 90% and 75% of the maximum amplitude, respectively. Mean fibrillatory rate in V1 (393±40.4 fpm) correlated significantly with V2 (391±43.3 fpm; r=0.976) and II (379±41.1 fpm; r=0.878). With an interval of 13.6±3.84 minutes mean fibrillatory rate in V1 was stable in 27 patients (400±51.2 fpm vs. 398±49.4 fpm; n.s.).

Conclusion: Processing of surface electrocardiograms recorded by the CardioLink (R) system can be used for AFCL analysis. Temporal and inter-lead stability of mean fibrillatory rate could be demonstrated. We conclude that the system is capable of assessing atrial fibrillatory activity from standard surface leads facilitating detailed investigation in AF patients.