Postextrasystolic Contractility Normally Decays in Alternans in Canine In Situ Heart

• Shimizu Juichiro

  Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine and Dentistry

• Mohri Satoshi

• Iribe Gentaro

• Kitagawa Yutaka

• Ito Haruo

• Araki Junichi

• Takaki Miyako

• Suga Hiroyuki

抄録

We have reported that the postextrasystolic (PES) potentiation of left ventricular (LV) contractility usually decays in alternans at heart rates above 80–100 beats/min in the canine excised, cross-circulated heart. We examined whether the PES contractility would also decay in alternans even in the canine in situ heart presumably more physiological than the excised heart. In anesthetized, ventilated, and open-chest mongrel dogs, we measured LV pressure and volume with a micromanometer and a conductance catheter cannulated into the LV and obtained LV end-systolic maximum elastance (E_max) as the reasonably load-independent contractility index. We inserted an extrasystole followed by a compensatory pause into steady-state regular beats at heart rates above 90 beats/min and analyzed the PES decay pattern of E_max. We found that E_max potentiated in the first PES beat decayed in alternans within 5–6 PES beats. This indicates that PES contractility also decays in alternans in the normal canine in situ heart.<br>

収録刊行物

• The Japanese Journal of Physiology

  The Japanese Journal of Physiology 53 (4), 313-318, 2003

  一般社団法人　日本生理学会

キーワード

• arrhythmia
• compensatory pause
• pressure–volume loop
• <i>E</i>_max
• Ca recirculation

詳細情報

• CRID: 1390282680018894080
• NII論文ID: 30015530088
• NII論文ID: 130004435874
• NII論文ID: 80016299365
• NII書誌ID: AA00691224
• DOI: 10.2170/jjphysiol.53.313
• COI: 1:STN:280:DC%2BD3srjtVGitA%3D%3D
• ISSN: 18811396
• ISSN: 0021521X
• NDL書誌ID: 6736903
• PubMed: 14606971
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I6736903
• Web Site: https://search.jamas.or.jp/link/ui/2004229768
• 本文言語コード: en
• データソース種別:
  • JaLC
  • NDL
  • Crossref
  • PubMed
  • CiNii Articles
  • KAKEN
• 抄録ライセンスフラグ: 使用不可