冠動脈の"ステール"と静止状態の収縮機能の関連性は,心筋不全性心疾患を有するヒトの副産物依存性心筋内にある
G Holmvang1, S Fry, H A Skopicki
1Departments of Medicine (Cardiac Unit), Radiology, and Nuclear Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, USA.
Circulation
|May 20, 1999
まとめ
アデノシンストレステスト中の血流の低下である冠動脈ステール (冠動脈ステール) は,付随的依存性心臓セグメントの休息収縮機能不全と強く関連しています. この発見は,冠動脈ステールが,一部の心臓病患者の慢性障害に大きく寄与することを示唆しています.
科学分野:
- 心臓病学 心臓病学
- 核心臓病の心臓病学について
- 発血不全性心臓病 発血不全性心臓病とは
背景:
- 副産物依存性心筋の休息アシンर्जीは,冠動脈ステールと相関すると仮定されています.
- 冠動脈ステール (Coronary steal) とは,冠動脈に依存する領域における高血症の間,血流が減少する現象である.
研究 の 目的:
- 慢性発血性心疾患の患者の静止状態の心筋収縮機能と冠動脈ステールとの関係を調査する.
- 慢性収縮性障害における冠動脈ステール対減少フローリザーブの役割を決定する.
主な方法:
- [13N]アンモニアによるポジトロン放出トモグラフィー (PET) を用いて,心筋血流と血流準備量を測定した.
- 冠動脈血管図は,狭窄症の重度と付随供給を評価した.
- エコーカルディオグラフィーまたはコントラスト心室図は,地域壁の動きを評価した.
主要な成果:
- "ステール" (アデノシンによる流れの減少) の付帯依存のセグメントは,ステールのないセグメントまたは正常な収縮のセグメントと比較して,静止血流がより高いことを示しました.
- 通常収縮するセグメントではフロー・リザーブが高かったものの,重複が著しくあった.
- 鉄鋼を証明したセグメントは,ほぼ常に休憩アシナジーを示した (22/23),一方,鉄鋼以外のセグメントは,アシナジーを示した頻度が低い (24/39).
結論:
- アデノシンストレス中の心筋血流の減少によって識別される冠動脈ステールは,付随的依存性セグメントの休息収縮機能不全と強く関連しています.
- 冠動脈ステールは,選択された患者の慢性収縮性障害の病原性における重要な要因であるようです.
- 単純に心筋のフロー・リザーブを減少させると,これらの患者の慢性的な収縮機能不全を引き起こすことにおいて,冠動脈ステールよりも批判的ではないかもしれません.
関連する概念動画
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