Location and ratio of high and low contact force during left atrial mapping

Abstract

Purpose: The aim of this study was to evaluate the location and the ratio of high/low contact force (CF) during left atrial (LA) mapping. Methods: CF during point-by-point LA mapping were assessed in 50 patients. In 30 patients, the operators were blinded to the CF during the procedure (Group A). In 20 patients, the CF was displayed to the operators (Group B). As a parameter of the catheter stability, relative standard deviation (RSD=standard deviation of CF*100 /mean CF) was calculated at each mapping point. Data were analyzed according to 11 predefined areas (Figure). In Group B, the optimal CF was defined to be 10-40g and the operators attempted to acquire points (pts) in this optimal range. We compared the CF and the catheter stability between 2 groups. Results: A total of 5866 mapping pts were analyzed (3467 pts in Group A and 2399 pts in Group B). Mean CF was 20±19g in Group A and 19±11g in Group B. Low CF 40g was noted at 414 pts (12%) in Group A and 67 pts (3%) in Group B (P 100g was noted at 22 pts (0.6%) in Group A, no CF>100g point was noted in Group B (P<.001). RSD was significantly lower in Group B than in Group A (30% vs 33%, P<.001), suggesting better catheter stability in Group B. Particularly in mitral isthmus and ridge areas, in Group B, CF was significantly higher (15±11g vs 10±10g, P<.001; 13±11g vs 8±9g, P<.001) and RSD was lower (32% vs 41%, P<.001; 27% vs 39%, P<.001) as compared to Group A. ![Figure][1] Figure 1. CF distribution and LA sites Conclusions: There are considerable number of mapping pts with high/low CF during CF-blinded procedure. CF sensing catheter appears to be helpful to avoid both unnecessary high and low CF, which may have clinical impact on the catheter ablation. [1]: pending:yes