The present disclosure describes a method for targeted delivery of permanently-acting or temporarily-acting neurotoxins, neurosuppressants, or other compounds having a neurologic effect to specific locations of the heart, including for example, but not limited to, nodes of the cardiac autonomic nervous system such as the atrial ganglionated plexi (GP). Chemical ablation of the atrial GP as described herein via magnetically-targeted magnetically-susceptible nanoparticles can effectively suppress GP activity and atrial fibrillation related, thereto without permanent damage to either myocardium or intrinsic CANS.