PO-02-216 SEGMENTAL INCREASE IN HETEROGENEITY OF REPOLARIZATION CORRESPONDS TO REGIONS OF DECREASED INNERVATION AFTER MYOCARDIAL INFARCTION

Myocardial infarction (MI) results in a dense scar region surrounded by heterogeneous remodeled border zone. In this denervation and nerve regeneration during healing could be dependent contribute to segmental differences the functional substrate for arrhythmias. To examine regional electrophysiological remodeling relation perfusion innervation changes after myocardial infarction. Anterio-septal MI was induced 6 domestic pigs 120-minute occlusion of left anterior descending artery (LAD) followed reperfusion. After one month, PET-MR imaging performed evaluate (13N-ammonia) (11C-epinephrine), together with late gadolinium enhanced MR quantification. The next day electro-anatomical mapping performed. BZ defined using contact as bipolar voltage between 0.5 1.5 mV. A non-contact recording 64-electrode array translated 2048 electrograms distributed over LV (EnSite PrecisionTM, St. Jude/Abbott Medical). each points 25 consecutive beats were processed determine beat-to-beat variability repolarization (BVR). Spatial heterogeneity quantified point time within 1cm radius neighborhood. size 14.2±3.2% ventricle on imaging. defects significantly larger (22.3±3.2%, P<0.01 28.1±4.3%, respectively). defect also than (P=0.03). Regional analysis revealed less versus septal zone (14.2±2.9 %/min vs 18.6+3.1 %/min, P<0.01). animal electrophysiology study unsuccessful due high baseline heart rate (>120 BPM). remaining animals, average spatial higher (5.8±3.0 ms 3.8±2.6 ms, Additionally, maximum BVR tended (2.6±1.3 2.02±0.77 P=0.08). resulting from LAD occlusion/reperfusion leads increased side infarct, correlating region.