*These two authors contributed equally. Short Title: Impaired Innervation After MI Address for Correspondence:

Impaired catecholamine handling in the viable infarct border zone may play an important role in ventricular remodeling and lethal arrhythmia. We sought to get further biologic insights into cardiac sympathetic neuronal pathology after myocardial infarction, using multiple tomographic imaging techniques. Methods – In a porcine model of myocardial infarction (n=13), positron emission tomography (PET) and magnetic resonance imaging (MRI) were performed after 4-6 weeks and integrated with electrophysiologic testing and post-mortem histology. Results- PET with the physiologic neurotransmitter carbon-11 epinephrine, which is sensitive to metabolic degradation unless it is stored and protected in neuronal vesicles, identified a defect exceeding the perfusion defect (defined by nitrogen-13 ammonia; defect size in all animals: 42±12 vs 35±12 % of left ventricle, p<0.001). In a subgroup of 7 animals, defect of the metabolically resistant catecholamine C-11 hydroxyephedrine was smaller when compared to epinephrine(41±8 vs 47±6 % of left ventricle, p=0.004), while defect of a third catecholamine, C-11 phenylephrine, which is sensitive t