Po-03-094 image integration in ventricular tachycardia (vt) ablation using sense2 protocol mapping

We have previously developed the sense protocol functional substrate mapping technique for VT ablation. This involves targeting areas of decremental signal delay during single extra pacing at short coupling interval. However, functional substrate characterization can involve protracted mapping time. We incorporated the MRI and CT data using ADAS-3D software into the mapping workflow to integrate structural mapping information into the functional mapping substrate characterization to improve procedural efficiency. Cardiac MRI/CTs were performed on 33 patients with ischemia-related VT (group A). These were processed with the ADAS-3D software to characterize the extent of ventricular scars. Focused substrate maps were then performed in patients, guided by the extent of ADAS scar and corridors, looking at the scar substrate in intrinsic rhythm and then functional channels using single extra pacing from the RV apex. Following the delineation of functional channels pace mapping and entrainment mapping were used to confirm targets for ablation. Group A was then compared to a matched cohort who underwent sense protocol mapping without MRI (group B) and an institutional cohort who underwent conventional mapping and ablation using entrainment or pace mapping (group C). 33 patients (mean age 68 years; 31 male subjects, mean EF 32%) underwent ablation. Median procedure time was 175 minutes compared with 305 and 246 minutes in groups B and C(p=<0.001) Mean substrate mapping time was 17 mins vs 80 and 63 mins in groups B and C (p=<0.001). 85% of patients were free from symptomatic VT/ anti-tachycardia pacing or implantable cardioverter defibrillator shocks at a median follow-up of 171 days. The mean VT burden was reduced from 22 events per patient in the six months pre-ablation to 1 event per patient in the median follow-up period of 171 days post-ablation (p=0.02). Sense2 protocol showed a reduced probability of device therapy compared with institutional and sense protocol (Log-rank p=0024 in the figure). The Sense2 protocol integrated structural MRI findings into functional signal ablation of VT. It shortened procedure times by enabling focused substrate maps to be performed without requiring complete geometry. Outcomes compare favourably with our previous data from sense protocol but with significantly shorter procedure times. There were improved outcomes compared to our institutional standard ablation cohort.