心臓移植後の運動中に左心室のリラックスが不十分加速する
W J Paulus1, J G Bronzwaer, H Felice
1Cardiovascular Center, O.L.V. Ziekenhuis, Aalst, Belgium.
Circulation
|October 1, 1992
まとめ
心臓移植を受けた人は,健康な人と比較して,運動中に左心室のリラックスが低下しています. 左心室圧縮の減衰の時間常数で測定されるこの減少したリラックス反応は,移植後のダイアストリック機能に影響します.
科学分野:
- 心臓病学 心臓病学
- 移植医療 移植医療について
- 生理学 生理学とは
背景:
- 運動は心臓移植後の左心室の充填圧を増加させ,心拍数応答の鈍化とアロ移植特性の変化に起因する.
- 左心室のリラックスがこれらの圧力変化に与える具体的な影響は,まだ十分に研究されていない.
研究 の 目的:
- 心臓移植を受けた患者の運動に対する左心室のリラックス反応を調査する.
- この反応を健康な個人の反応と比較する.
- ベータアドレノレセプター刺激,アフターロードの軽減,およびアロインプラントのリラクゼーションに対するカルシウム増加の影響を調査する.
主な方法:
- チップ・マイクロマノメーターで左心室圧力の記録と,27人の移植受容者と9人の対照群の血液動力学的評価を行った.
- 運動ストレステスト,ドブタミン注入,ニトロプロシド注入,およびポストエクストラシストリック増強が採用されました.
- 左心室のリラクゼーション率は,左心室の圧力低下 (T) の時間常数を使用して定量化されました.
主要な成果:
- 運動は,対照群 (42±7〜34±6 ms) と比較して,移植受容者 (43±6〜40±8 ms) のTの縮小を小さくした.
- 移植を受けた患者は,対照群とは異なり,運動中に左心室の最小気圧上昇を示した.
- アロ移植のリラクゼーションは,ドブタミン,ニトロプロシド,およびポストエクストラシストリック増強に対する変化する反応を示し,一部ではリラクゼーションの障害を示した.
結論:
- 心臓移植を受けた患者は,健康な対照群と比較して,運動中に左心室のリラックスが弱まったことを示しています.
- リラックス反応の低下は,移植後の充填圧の上昇に寄与する可能性があります.
- 薬理学的介入と増強により,アロ移植のダイアストリック機能の複雑な変化が明らかになった.
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