Na ((+) / H ((+) 交換器の阻害は,急速なペースが誘発した心房収縮機能障害の発達を遅らせます

G T Altemose¹, D P Zipes, J Weksler

¹Krannert Institute of Cardiology, Indiana University School of Medicine, Indianapolis 46202, USA.

Circulation

|February 7, 2001

まとめ

HOE642でNa(+) / H(+) 交換器 (NHE) を遮断すると,心拍が急速なときに左心房の機械的機能を有意に保ち,心房動後の心房麻痺を軽減します.

科学分野:

心臓病学心臓病学
電気生理学電気生理学
心臓生理学心臓生理学

背景:

心房の機械的麻痺は,心房細動の後も持続することがあります.
快速率に関連する心房収縮機能障害のメカニズムは完全に理解されていません.
潜在的なメカニズムには,イシュケミア,pHの変化,カルシウム過負荷が含まれます.

研究の目的:

急速な心拍数によって誘発される心房収縮機能不全に対するNa(+) / H(+) 交換器 (NHE) 阻害の効果を調査する.
NHEの封鎖が急速なペースで前庭のメカニカル機能を変化させるという仮説を検証する.

主な方法:

23匹の犬に5時間の急速右心房ペースを施した.
動物は,NHE阻害剤 (HOE642),塩分液 (対照群) またはニフェディピンを投与された.
左心房機能は,ソノミクロメーター,食道横断心房エコー,および血液動力学的モニタリングを使用して評価されました.

主要な成果:

NHEの阻害は,対照群とニフェディピン群と比較して,左心房断片縮小の減少を著しく減少させた.
左心房付属体の収縮速度 (LAACV) は,対照群と比較して,NHE阻害剤群で有意に保存されました.
LAACVは,ニフェディピン群と比較して,NHE阻害剤群でも有意に保存されました.

結論:

HOE642の治療は,急激な心房拍数によって引き起こされる左心房の機械機能の低下を効果的に鈍化させます.
NHE封鎖は,急速なペースの時に心房収縮機能に対する保護効果を示しています.

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