略語大辞典 [Med] 23 SA sinoatrial (node) 洞房(結節). 心臓のペースメーカー組織. 上大静脈と右心房の接合部の上にある. sinoatrial (node); or SAN; or nodus sinuatrialis; a tissue in the heart; the primary site of automaticity, from which the initial stimulus for muscle contraction spreads through the atrial musculature; [Med 丸善「略語大辞典」JLogosID : 11858439