Visualization of radionuclide imaging and activation recovery intervals on the epicardial surface

Greater knowledge of the factors influencing ventricular arrhythmias will aid in the identification people who are at risk for cardiac sudden death. The authors investigated whether regional heterogeneity of sympathetic innervation results in heterogeneous distributions of repolarization responses and whether this heterogeneity is a substrate for arrhythmias. The authors found the distribution of myocardial sympathetic nerve endings in autoradiographic images, and they measured repolarization changes by determining activation recovery intervals (ARI) from unipolar electrograms on the surface of the heart. An epicardial surface was extracted from autoradiographic images to display the distribution of innervation, and the activation recovery intervals were mapped onto the epicardial surface.