著者 Wada, Tadashi| Nakahama, Makoto| Toda, Hironobu| Watanabe, Atsuyuki| Hashimoto, Katsushi| Terasaka, Ritsuko| Nakamura, Kazufumi| Yamada, Nobuyuki| Ito, Hiroshi|
発行日 2013
出版物タイトル ISRN Cardiology
2013巻
資料タイプ 学術雑誌論文
JaLCDOI 10.18926/AMO/31492
フルテキストURL fulltext.pdf
著者 Yamada, Nobuyuki|
抄録 <p>Vectorcardiograms were recorded with the Frank lead system using electrodes positioned at the level of the 5 th intercostal space with the subject in the supine position. Deep inspiration produced the following significant changes compared with deep expiration: (1) the maximum leftward forces of the P, QRS, and T vectors decreased, whereas the maximum anterior and posterior forces of the QRS and T vectors increased; (2) the maximum spatial QRS vector decreased in magnitude; (3) the maximum spatial P, QRS, and T vectors shifted vertically, posteriorly and vertically, and anteriorly, respectively; and (4) the spatial QRS-T angle increased remarkably. The spatial instantaneous QRS vectors were analyzed at 5 msec intervals in 35 of the 61 subjects. With inspiration, the 35- through 50-msec vectors shifted posteriorly with markedly reduced leftward forces and increased posterior forces. It was suggested that the respiration-related vectorcardiographic changes reflected cardiac anatomic positional change, distortion of lead-field potential by lung gases, and other mechanisms. Since the respiratory effect is potentially important for vectorcardiographic interpretation, vectorcardiograms should be recorded under identical respiratory status.</p>
キーワード respiration vectorcardiogram Frank lead system maximum spatial vector instantaneous QRS vector
Amo Type Article
発行日 1985-08
出版物タイトル Acta Medica Okayama
39巻
4号
出版者 Okayama University Medical School
開始ページ 297
終了ページ 313
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 4050536
Web of Sience KeyUT A1985APN0700006
JaLCDOI 10.18926/AMO/31008
フルテキストURL fulltext.pdf
著者 Saito, Daiji| Ueeda, Masayuki| Hina, Kazuyoshi| Watanabe, Hirofumi| Mima, Tsutomu| Hasui, Masahiro| Yamada, Nobuyuki| Haraoka, Shoichi| Tsuji, Takao|
抄録 <p>The effect of the heart rate and myocardial contractile force on the extravascular resistance to blood flow of the left anterior descending coronary artery (LAD) was evaluated in 15 mongrel dogs anesthetized with sodium pentobarbital. The LAD was maximally dilated by intracoronary infusion of adenosine, which precluded the influence of vasomotor tone. Increases in the heart rate and myocardial contractile force decreased coronary blood flow in the absence of a change in coronary perfusion pressure. The changes in mean coronary resistance showed a significant linear relationship to changes in developed tension. The changes in coronary resistance caused by varying the heart rate and contractile force were so small that a normal coronary vascular tree could easily compensate for the increase in resistance. However, it is supposed that with critical stenosis of the vascular tree even a small increase in resistance might cause deleterious effects on coronary blood flow.</p>
キーワード contractile force tachycardia extravascular resistance coronary flow adenosine
Amo Type Article
発行日 1988-12
出版物タイトル Acta Medica Okayama
42巻
6号
出版者 Okayama University Medical School
開始ページ 335
終了ページ 342
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 3239438
Web of Sience KeyUT A1988R743300005
JaLCDOI 10.18926/AMO/30698
フルテキストURL fulltext.pdf
著者 Saito, Daiji| Yasuhara, Koichiro| Takeda, Hikaru| Hyodo, Tatuo| Yamada, Nobuyuki| Uchida, Toshiaki| Haraoka, Shoichi| Nagashima, Hideo|
抄録 <p>Changes in the stenotic resistance of a coronary artery following brief coronary occlusion were studied in the anesthetized open-chest dog. A critical coronary stenosis was constructed by tying a thick string around the circumflex coronary artery (LCx) near its origin. The LCx was occluded for 5, 10, 15, 20 and 30 seconds with and without coronary stenosis then the reactive hyperemia was observed. In the absence of the stenosis, resistance of the segment of the large coronary artery remained unchanged during the reactive hyperemia independent of the duration of occlusion. In the presence of the stenosis, however, stenotic resistance increased for a certain time after the release of occlusion. This increased resistance lasted longer with more severe stenosis and with longer duration of coronary occlusion. These results suggest that stenotic resistance can increase dynamically, and that the duration of increased resistance may reflect the severity of the stenosis.</p>
キーワード stenotic resistance reactive hyperemia distal coronary pressure
Amo Type Article
発行日 1982-06
出版物タイトル Acta Medica Okayama
36巻
3号
出版者 Okayama University Medical School
開始ページ 199
終了ページ 205
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 7113744
Web of Sience KeyUT A1982NV62100004