発血性心筋縮後の収縮: 積極的な収縮または被動的な後退?
Helge Skulstad1, Thor Edvardsen, Stig Urheim
1Institute for Surgical Research and Department of Cardiology, Rikshospitalet University Hospital, Oslo, Norway.
Circulation
|August 7, 2002
まとめ
発血性心筋縮後の収縮は,特に低運動セグメントでは,活発な収縮と活性を示す可能性があります. ストレングドップラーエコーカルディオグラフィーはこれを効果的に定量化し,活性の高い心臓組織を特定するのに役立ちます.
科学分野:
- 心臓病学 心臓病学
- エコーカルディオグラフィー エコーカルディオグラフィー
- 心筋活力 筋動脈活力について
背景:
- 静脈後縮小 (PSS) は,不全性心筋活性のマーカーとして提案されている.
- PSS (アクティブ・コントラクション対パッシブ・リコイル) の正確なメカニズムと,ストレンス・ドップラー回声心臓検査 (SDE) による定量化については,明確化が必要です.
研究 の 目的:
- PSSがアクティブ・ファイバー・ショートニングか,パッシブ・リコイルかを判断する.
- SDEがPSSを正確に定量化できるかどうかを評価する.
主な方法:
- 麻酔を受けた犬では,左心室 (LV) 圧力,心筋長軸ストレイン (SDE) およびセグメント長 (ソノミクロメトリー) を測定した.
- LV圧力セグメント長とLVストレスセグメント長ループ分析は,LAD狭窄と閉塞の間にアクティブ収縮を定義しました.
主要な成果:
- LAD狭窄はPSSを増加させ,分析は低運動性/低運動性セグメントで活性であることを示した.
- LADの閉塞は不運動を引き起こし,PSSは一部のセグメントで受動的な後退になりました.
- SDEは,PSSの定量化のためのソノミクロメトリーと良好な相関性を示した (r=0.83).
結論:
- PSSは非特異的であり,不運動のセグメントでは被動的であり,低運動/低運動のセグメントでは活発である.
- ヒポキネティック/アキネティックセグメントのアクティブPSSは,活発に収縮している,生存可能な心筋を意味します.
- SDEは,PSSを定量化し,心筋活性を特定するための有効な臨床ツールです.
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