静脈収縮の改善と機械的再同期は,左束の枝状ブロックと拡張性欠陥心臓の電気的同期を必要としません
Christophe Leclercq1, Owen Faris, Richard Tunin
1Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Md, USA.
Circulation
|October 3, 2002
まとめ
電気的同期ではなく,機械的再同期が,LBBB患者の心臓機能を改善します. ペースアップの利点は,調整された筋肉の動きから生じ,衰弱した心臓のシストリック機能を高めます.
科学分野:
- 心臓病学 心臓病学
- バイオメディカルエンジニアリング
- 心臓電気生理学 心臓電気生理学
背景:
- 左バンドル・ブランチ・ブロック (LBBB) は,心不全の患者の心収縮機能を損なう.
- 双心室 (BiV) と左心室 (LV) のペースは機能を改善しますが,電気シンクロニーの役割は不明です.
研究 の 目的:
- 電気的同期が機械的同期と,LBBB障害の心臓のペースから機能的な改善に必要かどうかを調査する.
主な方法:
- LBBBを誘発した犬の表心臓マッピング,タグされたMRI,および血液動力学的測定を用いた.
- 電気的活性化,機械的再同期,心臓機能に対する右心房,LV,BiVのペース効果を比較した.
主要な成果:
- BiVとLVの両方のペースは,LBBBにおける心房ペースと比較して,心臓の血液動力学を大幅に改善しました.
- ペースによって引き起こされた機能的改善は,機械的再同期と相関しています.
- BiVのペースは電気分散を減少させ,LVのペースは増加させました.
結論:
- 電気的同期は,機械的同期とペースの機能的な利点を達成するために必要とされません.
- LBBB心臓におけるBiVまたはLVペースのシストリック改善の主な要因は,メカニカルコーディネーションである.
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