心房颤动的研究现状_江洪.ppt

AF发生机制的再认识：对消融治疗的指导 请注意，这个AF的维持需要Ach，也就是说需要自主神经因素。 Background—Recent studies demonstrated spatiotemporal organization in atrial fibrillation (AF). We hypothesized that waves emanating from sources in the left atrium (LA) undergo fragmentation, resulting in left-to-right frequency gradient. Our objective was to characterize impulse propagation across Bachmann’s bundle (BB) and the inferoposterior pathway (IPP) during AF. Methods and Results—In 13 Langendorff-perfused sheep hearts, AF was induced in the presence of acetylcholine (ACh). Fast Fourier transform of optical and bipolar electrode recordings was performed. Frequency-dependent changes in the left-to-right dominant frequency (DF) gradient were studied by perfusing D600 (2 μmol/L) and by increasing ACh concentration from 0.2 to 0.5 μmol/L. BB and IPP were subsequently ablated. At baseline, a left-to-right decrease in DFs occurred along BB and IPP, resulting in an LA–right atrium (RA) frequency gradient of 5.7±1.4 Hz. Left-to-right impulse propagation was present in 81±5% and 80±10% of cases along BB and IPP, respectively. D600 decreased the highest LA frequency from 19.7±4.4 to 16.2±3.9 Hz (P0.01) and raised RA DF from 8.6±2.0 to 10.7±1.8 Hz (P0.05). An increase in ACh concentration increased the LA-RA frequency gradient from 4.9±1.8 to 8.9±1.8 Hz (P0.05). Ablation of BB and IPP decreased RA DF from 10.9±1.2 to 9.0±1.5 Hz (P0.01) without affecting LA DF (16.8±1.5 versus 16.9±1.8 Hz, P=NS). Conclusions—Left-to-right impulse propagation and frequency-dependent changes in the LA-RA frequency gradient during AF strongly support the hypothesis that this arrhythmia is the result of high-frequency periodic sources in the LA, with fibrillatory conduction away from such sources.  我们一般认为chronic atrial rapid pacing引起的AF model都是折返机制，但是这个研究显示了chronic atrial rapid pacing引起的sustained AF可能是Focal机制，甚至是AF的主导因素。 Focal activation in the LSPV of dog 2?during sustained AF (unipolar recording). A-C: isochronal maps of 3?beats at