人間の心不全における心筋筋力の周波数関係の変化
L A Mulieri1, G Hasenfuss, B Leavitt
1Department of Physiology and Biophysics, University of Vermont College of Medicine, Medical Center Hospital of Vermont, Burlington 05405.
Circulation
|May 1, 1992
まとめ
閉塞性心不全 (CHF) は,心筋収縮性を低下させ,衰弱した心筋における緊張生成の減少と周波数応答の変化を示します. これらの内在的な心筋疾患は,拡張性心筋疾患における左心房機能の異常に寄与する.
科学分野:
- 心臓病学 心臓病学
- 生理学 生理学とは
- バイオケミストリー バイオケミストリー
背景:
- 閉塞性心不全 (CHF),特にイディオパシー拡張心筋病症は,運動中に異常な左心室 (LV) 機能が特徴です.
- 観察された異常は,低血圧体積減少,低血圧上昇/低下率,および心拍数依存的収縮性増強 (ボウディッチ・トレッペ) の障害を含む.
研究 の 目的:
- 心筋収縮機能の異常を研究し,定量化するために,失敗する対不失敗する人間の心臓.
- 拡張性心筋疾患における異常な心室機能に寄与する内在心筋機能障害を特定する.
主な方法:
- NYHAのクラスIVの故障と非故障のヒト心臓から分離された左心室筋帯のストライプが研究されました.
- 実験は生理学的温度 (37°C) と様々な収縮周波数 (12-240分−1) で行われた.
- 2,3-ブタネジオンモノキシム (BDM) を使用した新しい方法により,切断中の切断傷害から心筋筋帯が保護されています.
主要な成果:
- 機能不全の心筋は,機能不全の心筋と比較して,異対比的な震動の緊張が著しく減少した (それぞれ72分と174分−1で48%,80%減少).
- ピークテンション-周波数関係は,心不全患者ではより低い周波数で発生した (心不全患者では平均81±22分−1対174±4分−1).
- 機能不全の心筋は,頻度とともに緊張が著しく増加する一方で,機能不全の心筋は,60~150分−1.1の間には有意な変化を示さなかった.
- 緊張の上昇と低下の速度は,衰えていない筋肉では,しかし衰えていない筋肉では,並行して緊張の緊張を引く.
結論:
- 組織的要因とは無関係な心筋収縮性の内在的変化は,拡張性心筋疾患における左心房機能の異常に寄与する.
- 単離された心筋膜の発見は,in-vivo測定と定量的に一致し,心筋膜機能不全の主要な役割を支持しています.
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