Optimal cut‐off value for endocardial bipolar voltage mapping using a multipoint mapping catheter to characterize the scar regions described in cardio—CT with myocardial thinning

摘要

Abstract Introduction To investigate whether the current standard voltage cut‐off of <0.5 for dense scar definition on endocardial bipolar voltage mapping (EBVM), using a high‐resolution multipoint mapping catheter with microelectrodes (HRMMC), correctly identifies the actual scar area described on CT with myocardial thinning (CT MT). Methods Forty patients (39 men; 67.0?±?9.0?y/o) with a history of transmural myocardial infarction (mean time interval since MI 15.0?±?7.9 years) and sustained ventricular tachycardia (VT) were consecutively enrolled. A CT MT was performed in each patient before VT ablation. The CT MT 3D anatomical model, including MT?layers, was merged with the 3D electroanatomical and EBVM. Different predefined cut‐off settings for scar definition on EBVM were used to identify the optimal ones, which showed the best overlap in terms of scar area with the different MT?layers. Results A cut‐off value of <0.2?mV demonstrated the best correlation in terms of scar area with the 2?mm thinning on CT MT (p?=?.04) and a cut‐off of <1?mV best overlapped with the 5?mm thinning (p?=?.003). The currently used <0.5?mV cut‐off for scar definition on EBVM proved to be the best area correlation with 3?mm thinning (p?=?.0002). Conclusion In order to better identify the real extent of scar areas after transmural MI as described on preprocedural CT MT, higher cut‐off values for scar definition should be applied if the EBVM is performed using a HRMMC.