Clinical assessment and comparison of annotation algorithms in high‐density mapping of regular atrial tachycardias
High‐density automated mapping of regular atrial tachycardia (AT) requires accurate assessment of the local activation time (LAT). LAT is conventionally annotated at the peak of the bipolar electrogram (EGM) or the maximal negative slope of the bipolar or unipolar EGM.1 However, these conventional methods of LAT assessment have some disadvantages: unipolar EGMs are prone to noise and far‐field potentials, whereas bipolar EGMs are influenced by wave front direction, electrode size, bipole orientation, and interelectrode spacing.3 To overcome the limitations encountered with the conventional annotation algorithms, a new hybrid annotation algorithm was developed.5 This new algorithm is a so‐called hybrid annotation algorithm as it uses both the bipolar and unipolar EGM to determine the LAT. This algorithm detects the maximal negative slope in the unipolar EGM within a predefined window demarcated by the beginning and the end of the bipolar activation complex. As such, more accurate annotation of the maximal negative slope can be achieved by blanking noise and far‐field in the unipolar EGMs.
This study evaluates a new automated high‐density mapping tool (ConfiDENSE) and compares the hybrid LAT annotation (LATHybrid) to the conventional bipolar peak (LATPeak) and maximal negative unipolar slope (LATSlope) annotation, with regard to correct interpretation of tachycardia mechanisms and ease of interpretation of the tachycardia.