Abstract 5682: Color-Coded 3D Entrainment Mapping: A New Approach for Analysis and Treatment of Atrial Macroreentrant Tachycardia
Atrial macroreentrant tachycardia (MRT) is a typical arrhythmia following AF ablation. Understanding the reentrant pathway is crucial for curative ablation. This prospective study evaluated a new concept for analysis and treatment of MRT based on color-coded 3D entrainment mapping. 24 patients presented with symptomatic MRT (CL 324+/−62 ms). Initial entrainment in HRA, RA isthmus and CS differentiated between right atrial (RA) and left atrial (LA) origin of the MRT. For LAMRT a single transseptal puncture provided access to the LA. Using nonfluoroscopic systems (Carto=8, NavX=12) sequential mapping of the target atrium was performed. On each mapping point entrainment was performed. The 3D position was paired with the color-coded information on the length of the return cycle. That way the reentrant pathway could be directly visualized. Procedure, radiation and RF time measured 212+/−27, 44+/−13 and 42+/−8 min. The initial re-entrant mechanism was as follows: typical RA isthmus dependent (n=1), atypical RA isthmus dependent (n=2), around SVC (n=1), around Fossa ovalis (n=3), perimitral (n=3), around a PV (n=5), through LA roof (n=4), around LAA (n=3), reentry within CS (n=2). Ablation terminated MRT in all patients. Following termination 9/24 (38%) patients showed other MRT, which were studied and ablated accordingly. In total 32 reentrant circuits were identified and ablated. All patients eventually terminated into SR. In case of LAMRT subsequent PV isolation was performed. At the end of the procedure 20/24 (83%) patients were non-inducible for AF and/or MRT on aggressive Burst stimulation at the atrial refractory period. On follow-up with serial 7-day-Holter none of the patients had recurrences of the ablated MRT. Color-coded 3D entrainment mapping is a useful tool for accurate understanding of the location of the reentrant circuit and subsequent planning of a strategic lesion line concept. That concept has evolved as the primary approach for patients with stable MRT in our institution.