低ゼロフロー圧力と最小の容量効果は,豚の最大血管拡張の間に,ダイアストリック冠動脈の圧力-フロー関係に作用する
Circulation
|September 1, 1984
まとめ
豚では,血流が停止する冠動脈圧 (Pzf) は右心房圧に近い. この低いPzfは,介入の影響を受けず,低血圧でも冠動脈の血流を維持するのに役立ちます.
科学分野:
- 心血管生理学 心血管の生理学
- ヘモダイナミクス (血動力学)
- 冠動脈循環 冠動脈循環について
背景:
- 冠動脈の圧力-流れ関係は,心筋 perfusion を理解する上で極めて重要です.
- 犬を対象とした以前の研究では,最大血管拡張時に血流が停止する高気圧 (Pzf) が報告されていた.
- 豚におけるPzfの行動と,付随の流れと冠動脈容量に影響を与える介入に対するその反応は,十分に特徴づけられていませんでした.
研究 の 目的:
- 豚の左前垂下冠動脈 (LAD) のPzfを測定するために.
- Pzf.に対する付随の流れと冠動脈容量に対する介入の影響を決定する.
- 豚のPzfを犬の以前に報告された値と比較するために.
主な方法:
- 圧力とフローの測定のためのLADのインストゥルメンテーションで44頭の豚が研究されました.
- 最大血管拡張 (アデノシン) 中の部分LAD閉塞は,圧力-流れ関係を構築するために使用されました.
- 介入には,一時的な右冠動脈 (RCA) 閉塞,左心室内静脈圧 (LVSP) 増加,心拍数増加が含まれていました.
主要な成果:
- 豚のLADにおける遅期ダイアストリックPzfは,犬において以前に報告されたものより有意に低く,平均7.0 +/- 2.2mm Hgであり,右心房圧のほんのわずかに上でした.
- 平均Pzfは12.1 +/- 3.1mm Hgで,右心房圧に近い値でした.
- Pzfは安定し,RCA閉塞,LVSP増加,または心拍数増加の間に重要な変化を示さなかったため,Pzfは付随の流れと冠動脈容量変化から独立していることを示した.
結論:
- 豚のPzfは一貫して低く,右心房圧に近い.
- この低いPzfは,付随の循環や冠動脈容量を変える介入に関係なく維持されます.
- 低いPzfは,減少した perfusion 圧力で十分な冠動脈の血流を確保するために有利です.
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