HETEROGENIC PROCESS OF THE APPEARANCE OF THEATRIAL ELECTRICAL REMODELING IN CANINE RAPIDSTIMULATION MODEL

摘要

Background; Although it is well known that rapid atrial activation causes electrical remodeling, processes of electrical remodeling at different atrial sites are still unclear. In present study, atrial electrophysiologic parameters were monitored at several atrial sites during rapid atrial stimulation for 2weeks to clarify heterogeneity of process of atrial electrical remodeling.Methods: RAA or LAA was paced with 400bpm for 2weeks. At 4atrial sites of RAA, Bachmann's bundle (BB), IVC and LAA, AERP, AERP dispersion(AERPd) and inducibility of atrial fibrillation were evaluated at several points in pacing and recovery phase.Results: AERP shortening ( A AERP)was heterogeneous in 4atrial sites in process of atrial electrical remodeling. In RAA stimulation group, A AERP was larger in RAA and LA sites than other sites. In contrast, LAA stimulation group showed larger A AERP at BB site than others. Maximal AERPd was larger in LAA than RAA stimulation group. AF inducibility was highest at LA site in both groups, but inducibility was higher in LAA than RAA stimulation group.Conclusions: In this model, process of the atrial electrical remodeling was heterogeneous in different parts of atria. A AERP was largest at LA site regardless of rapid pacing site, but AERPd was larger and AF inducibility was higher in LAA stimulation group than RAA stimulation group. LA seemed to play an important role in causing AF in canine rapid stimulation model of atrial electrical remodeling.