Please click here to obtain permission to reproduce this image.
Click on image to view larger version.
Figure 1 Display of virtual electrograms. Multiple virtual electrograms were simultaneously viewed in a linear or grid format after being selected at the area of interest with the computer mouse. An isopotential map during ventricular tachycardia (VT) (cycle length 380 ms) is shown in these three panels. In each panel, the left ventricular reconstruction is shown with the septum, base and apex indicated. The chamber is shown in an open view of the entire endocardial reconstruction. The anterior septum on the far left of each endocardial reconstruction is anatomically continuous with the anterior septum on the far right of each model. In each panel, the isopotential map identifies the site of endocardial activation associated with the onset of the QRS complex during VT. The maximum negative potential, representing the leading edge of the wave of depolarization, is shown in white. A wireframe depiction of the inflated noncontact balloon catheter is shown in the top panel but not in the lower panels. In the top panel, eight closely-spaced virtual electrograms have been selected for viewing in a linear format. In the middle panel, a linear format of eight virtual electrograms with a larger interelectrode distance is displayed. An example of 16 virtual electrograms in a grid format is provided in the bottom panel. The letters on the isopotential map correspond to the virtual electrograms. Surface ECG lead I also is shown.
|
