부산대학교 도서관

The purpose of this study is to analyze the electrical propagation patterns from patients with persistent atrial fibrillation (AF). Unipolar electrograms $(\sim 1$ minute) were recorded sequentially in atrial chambers from 5 patients with persistent AF prior to ablation using a 64-electrode basket catheter. Raw unipolar signals were processed using a suite of signal processing approaches including: 1) A Savitzky-Golay filter, 2) a standard QRS subtraction and 3) a local variability approach which uses a local integral to enhance the signals. Recurring patterns of electrode activation and AF drivers were then identified by using activation time maps and dominant frequency analysis, and by screening through the entire isopotential movies of each basket recording. Localized sources in the form of either localized reentries $(N=1)$ or focal impulses $(N=4)$ were observed in all of the patients studied. Interestingly, all localized sources were found in the left atrium (LA) near the pulmonary veins with the exception of 1 patient where an additional focal impulse was also detected in the right atrium (RA). Disorganized activity was observed in the RA of 3 patients, though their respective LAs were driven by localized sources. These results suggest that either localized sources in the LA or disorganized activity in the RA or both of these mechanisms may be the predominant triggers of persistent AF