冠動脈内ニトログリセリンの投与が冠動脈狭窄時に流動の相パターンとトランムラル分布に与える影響
M Goto1, A E Flynn, J W Doucette
1Department of Medical Engineering and Systems Cardiology, Kawasaki Medical School, Kurashiki, Japan.
Circulation
|June 1, 1992
まとめ
動脈内ニトログリセリンは,心筋梗塞の逆流の増加により,動脈内ニトログリセリンは,心筋梗塞の心臓の血流の増加にもかかわらず,下腸内心臓の血流を損なうため,アンギナの緩和に失敗することがあります.
科学分野:
- 心血管生理学 心血管の生理学
- 薬理学 薬理学とは
背景:
- ニトログリセリンは,心筋小動脈不全症を効果的に緩和します.
- 冠内ナイトログリセリンはアンギナを緩和できず,心臓下髄血流に悪影響を及ぼす可能性があります.
- これらの効果の背後にあるメカニズムは,調査を必要とする.
研究 の 目的:
- ニトログリセリンが,心不全の心臓における冠動脈循環に及ぼす直接的な影響を調査する.
- ニトログリセリンの投与と冠動脈の血流パターンの関係を解明する.
主な方法:
- 80チャンネル,20MHzのパルスドップラー超音波フローメーターを使用して,心内冠動脈の流れを測定しました.
- 放射性微小球を用いて,心経血流の分布を評価した.
- 冠動脈狭窄を誘発した麻酔されたオープンチェスト犬における効果を研究した.
主要な成果:
- ニトログリセリンの投与は,静脈狭窄の冠動脈における遠端シストリックおよびダイアストリック圧力を低下させた.
- ニトログリセリンは,ダイアストリック前向きの流れを増加させましたが,シストリック逆流を大幅に増加させました.
- ニトログリセリンで心下流は増加したが,心下流は増加せず,心下流と心下流の比率が低下した.
結論:
- 冠動脈内ニトログリセリンの後,シストリック逆流の増加が重要な要因である.
- この増加した静脈逆流は,心下髄下血流の改善の失敗と密接に関連しています.
- この発見は,ニトログリセリンの限られた有効性の潜在的なメカニズムを,特定の不血症状態で示唆しています.
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