Differentiation of the "accessory" conduction system of the human heart.
D001283:Atrioventricular Node / Q000196:embryology; D006325:Heart Atria / Q000294:innervation; D006329:Heart Conduction System / Q000196:embryology*; D006346:Heart Septum / Q000294:innervation; D006801:Humans; D014684:Venae Cavae / Q000294:innervation