Use of the EnSite technology allowed real-time 3D mapping and precise localization of the areas of earliest activation, and safe radiofrequency ablation of three distinct areas without damage to the overall pacemaker function of the sinus node. In this case, the three distinct areas of early activation provided clarity in the diagnosis that was previously felt to be atrial tachycardia. Though current published case series lack long-term outcomes, it appears that use of the EnSite contact map and EnSite Array catheter to guide radiofrequency ablation of sites of earliest activation may simplify sinus node modification and possibly lead to more durable long-term outcomes in the treatment of IST.

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