Please click here to obtain permission to reproduce this image.
Click on image to view larger version.
Figure 2 (A) Isopotential maps showing the activation sequence (frames 1 to 6) of counterclockwise upper loop re-entry in the right posterior oblique view. Color scale for each isopotential map has been set so that white indicates most negative potential and blue indicates least negative potential. The activation wavefront propagates down the anterolateral right atrium (RA) near the superior vena cava (SVC) (frame 1) to the middle and inferior anterolateral RA (frame 2), then splits into two wavefronts (frame 3); one passes around the area of functional block, and the other passes through the cavotricuspid isthmus. The wavefront in the lateral RA continues through the gap (g) in the crista terminalis (CT) (frame 4) to the superior posterior RA (frame 5) and activates the atrial wall surrounding the SVC before reactivation of the anterolateral RA once again. (B) The virtual electrograms from the area of functional block (virtual 11 to 15) and the CT (virtual 16 to 20) including the conduction gap (virtual 16 to 18) demonstrate double potentials. The numbers 1 to 6 represent the time points at which the isopotential maps have been displayed in A. IVC = inferior vena cava.
|
