title: Noninvasive technique for detection of electrical activity during the P-R segment.
mesh_terms: D000818:Animals; D004285:Dogs; D004558:Electric Stimulation; D004562:Electrocardiography; D004594:Electrophysiology; D005071:Evoked Potentials; D006325:Heart Atria; D006329:Heart Conduction System / Q000502:physiology / Q000503:physiopathology*; D006352:Heart Ventricles; D011342:Procainamide / Q000494:pharmacology
chemical_list: D011342:Procainamide