Figure 1 Nonconducting Tissue Identification
A patient with sustained AT after Fanton Modification. (Movie I and Movie II in the Data Supplement). A: Bipolar voltage threshold is set arbitrarily 0.5 to 0.5 mV, with red representing voltage <0.5 mV and purple representing >0.5 mV. Ripple bars are seen to propagate in the red area on the map (yellow circle). B: After adjustment of voltage threshold, the area with propagating ripple bars appears as purple (yellow circle), representing conductive tissue. C, D: At this voltage setting, the ripple map of the RA during posterior scar-related flutter in this case that clearly delineated the critical isthmus located between the posterior scar and IVC. RA: right atrium; SVC: superior vena cava; CS: coronary sinus; IVC: inferior vena cava.