左心室のペースは,下痢性心室の相互作用を最小限に抑え,前負荷依存性シストリックパフォーマンスの改善を可能にします
R A Bleasdale1, M S Turner, C E Mumford
1Department of Cardiology, Wales Heart Research Institute, Heath Park, Cardiff CF14 4XN, United Kingdom. bleasdalera@aol.com
Circulation
|October 13, 2004
まとめ
左心室 (LV) のペースは,LVの充填に対する外部の制約を軽減し,心不全患者の効果的な充填圧と脳卒中量を改善します. このメカニズムは,スターリングメカニズムを通じて心臓の出力を強化します.
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
- 心不全に関する研究
背景:
- 左心室 (LV) のペースは,心不全患者の血動力学を改善することが知られている.
- この利点の潜在的なメカニズムは,心室の相互作用によるLV埋着に対する外部の制約を最小限にすることです.
研究 の 目的:
- LVパッシングがLV充填に対する外部制約を軽減するという仮説を検証する.
- LVのパッシングが,LVの充填圧と体積に与える影響を定量化するために.
主な方法:
- 13人の心不全患者 (NYHAクラスIII/IV) のLV圧力と体積を同時に測定するために導電性カテーテル法を使用しました.
- 下 vena cava occlusion 中の,LV pacing による,またはそのなしでの,終端腹圧量比を用いて,LV 充填に対する外部の制約を測定した.
主要な成果:
- LVパッシングは,LV充填に対する外部制約を大幅に軽減した (P<0.01).
- 効果的な充填圧は4.0mmHg (P<0.01) 増加し,LVの終末ダイアストリック体積が10mL増加した (P=0.01).
- ストロークボリュームは11mL (P<0.01) 増加し,LVストロークワークと最大dP/dtの増加が伴いました.
結論:
- LVパッシングは,血液動力学的改善の重要なメカニズムであるLV充填に対する外部制約を効果的に最小限に抑えます.
- 外部制約の減少により,効果的な充填圧が増加し,スターリングメカニズムを通じて,LVの末期透析体積とストローク体積が増加します.
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