著者
伊東 盛夫 有田 真 佐伯 和之 田上 三雄 福島 勇 矢永 尚士 真柴 裕人
出版者
THE PHYSIOLOGICAL SOCIETY OF JAPAN
雑誌
The Japanese Journal of Physiology (ISSN:0021521X)
巻号頁・発行日
vol.17, no.2, pp.174-189, 1967-04-15 (Released:2011-06-07)
参考文献数
35
被引用文献数
39 46

The sequence of spread of sinus node impulse to the venae cavae and the mechanisms of delay at the sinocaval junctional areas were studied with the microelectrode methods.The impulse from the pacemaker located in the sinus node spreads slowly in the nodal tissues (1-10cm/sec) and excites the crista terminalis. Spread is rapid in the crista (50-120cm/sec). Then the impulse spreads from theupper and lower ends of the crista through the sinocaval junctional areas (SC areas) to the right and left superior venae cavae. Conduction velocity is decreased in the SC areas (10-25cm/sec) and again increased in the superior venae cavae (40-80cm/sec). In the inferior vena cava, the conduction of impulse is always completely blocked in the vicinty of the ostium.The features of superior vena caval action potentials are closely similar to those of cardiac action potentials, showing the constant diastolic level, the rapid upstroke, the high amplitude, the clear plateau and the rapid conduction.The fibers in the SC areas apparently show a transitional stage from the nodal fibers to the superior vena caval fibers. The action potentials of the SC areas are intermediate in the amplitude and rate of rise between those of sinus nodal and superior vena caval action potentials, and often reveal a step on the upstroke. The activation of right atrium at high rate produced a delay and block localized to the SC areas. The action potentials of the SC areas show three different types of changes associated with the increased atrial rate: I) the decrease in the amplitude and rate of rise, II) the separation into two discrete spikes and III) the widening of the step-like prepotential.Several evidences were presented which suggest that the SC areas are the latent pacemakers.
著者
中川 幹子 藤野 孝雄 高橋 尚彦 石田 修二 渡邊 真理 丹羽 裕子 伊東 康子 桶田 俊光 犀川 哲典 伊東 盛夫
出版者
Japanese Heart Rhythm Society
雑誌
心電図 (ISSN:02851660)
巻号頁・発行日
vol.14, no.3, pp.177-188, 1994-06-30 (Released:2010-09-09)
参考文献数
32
被引用文献数
1

糖尿病患者の心拍変動およびQT間隔と, 自律神経障害および心臓死との関連を検討した.対象は健常人13例 (C群) , 糖尿病群は自律神経障害を合併しない生存群9例 (AN (-) 群) , 自律神経障害を合併する生存群21例 (AN (+) 群) および心臓死群10例 (CD群) である.ホルター心電図より低周波数成分 (LF) , 高周波数成分 (HF) , LF/HFおよびRR間隔標準偏差の平均 (SD) を, 標準12誘導心電図よりQTc間隔およびQTc dispersion (最大QTcと最小QTcの差) を求めた.AN (+) 群とCD群は, C群に比しLF, HF, LF/HFおよびSDの24時間平均値と, その日内変動は著明に低下していた.最大QTc間隔はC群に比し糖尿病群では有意に延長していたが, 糖尿病の3群間には有意差を認めなかった.QTc dispersionはC群に比しCD群のみ有意に大であった.CD群は時間経過とともにHFの低下とQTc dispersionの増加が認められた.以上の成績から, 糖尿病患者の心臓死と自律神経障害およびQTc dispersionによって示される心室筋再分極の不均一性との関連が示唆された.