Monophasic action potentials of the right atrium in @entity1 with XXXX .

@entity1 @entity13678 @entity955
To investigate the mechanism of @entity955 ( @entity955 ), monophasic action potentials (MAPs) from the @entity955 were studied in 7 @entity1 with paroxysmal @entity955 (PAF) and in 7 control individuals. The MAPs were recorded using a contact catheter during sinus rhythm and continuous pacing at the @entity13678 ( @entity13678 ) with pacing cycle lengths of 600, 500 and 400 ms. MAPs were obtained from 6 sites in each @entity1 . The MAPD90 was measured from onset to 90% of MAP repolarization. Average, maximal and minimal MAPD90 (avMAPD90, maxMAPD90 and minMAPD90) were obtained from all @entity1 . The dispersion of MAPD90 (dispMAPD90) was defined as the difference between maxMAPD90 and minMAPD90. The width of each atrial potential (WAP) and the wavelength index (WLI=MAPD90/WAP) were determined. Average, maximal and minimal WLI (avWLI, maxWLI and minWLI) were obtained from all @entity1 . The avMAPD90 and maxMAPD90 did not significantly differ between the 2 groups. The minMAPD90 in the PAF group was significantly smaller than that in the control group at @entity13678 pacing with cycle lengths of 500 and 400 ms (210+/-18ms vs 245+/-14 ms, p<0.05; 207+/-23 ms vs 238+/-20 ms, p<0.05; respectively). The dispMAPD90 was significantly longer in the PAF group than in the control group during sinus and @entity13678 pacing. The WAP value did not differ between the 2 groups. The minWLI in the PAF group was significantly smaller than that in the control group at @entity13678 pacing with cycle lengths of 500 and 400 ms (3.3+/-0.5 vs 3.8+/-0.3, p<0.05; 3.2+/-0.4 vs 3.7+/-0.3, p<0.02). A shortened and widened dispersion of atrial refractoriness may play an important role in the genesis of @entity955 . Furthermore, smaller wavelengths may form in the atrium of @entity1 with PAF.
