モビッツ型II心房閉塞のメカニズムとしての細胞活性化の機能的解離は,モビッツ型II心房閉塞のメカニズムである
M D Gonzalez1, B J Scherlag, P Mabo
1Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City.
Circulation
|April 1, 1993
まとめ
損傷したヒス・プルキンジェ系では,心拍数の増加がモビッツ型IIブロックの前に細胞解離を引き起こします. このブロックは,細胞解離を減らし,電気的活動を安定させます.
科学分野:
- 心臓病学 心臓病学
- 電気生理学 電気生理学
- 心臓伝導システムです.
背景:
- 発血性His-Purkinjeシステムにおけるモビッツ型II心房閉塞メカニズムは,完全に理解されていません.
- 新しい動物モデルにより,この伝導欠陥のインビボおよびインビトロ研究が可能です.
研究 の 目的:
- 発血性ヒス・プルキンジェ系損傷の動物モデルにおける電気生理学的変化を調査する.
- 異なる心拍数でモビッツ型II心房閉塞を引き起こすメカニズムを解明する.
主な方法:
- 犬では,前断面動脈の結合によって,血栓性損傷が誘発された.
- アトリアルペースは 2:1 の心房閉塞を誘発するために使用されました.
- 実験室内研究では,Heの束と束の枝のアクションポテンシャルと電図を同時に記録しました.
主要な成果:
- ペースの上昇は,アクションポテンシャルの振幅の低下と,ヒス・パーキンジェ系における細胞解離の増大につながった.
- 細胞解離の頻度は,アクションポテンシャルの振幅の減少と強く相関していた.
- ブロックの部位は,ペースやエクストラスティミュルの変化に合わせて動的にシフトする.
結論:
- 缺血性ヒス・パーキンジーの損傷では,速度の上昇が2:1ブロック前に細胞解離を引き起こします.
- モビッツ型IIブロックは,細胞解離を減少させることで,より安定した活性化パターンを提供します.
関連する概念動画
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01:28Mechanism of Cardiac Arrhythmias
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01:19Conduction System of the Heart
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The pacemaker cells are located in two primary nodes: the sinoatrial (SA) node and the atrioventricular (AV) node. The SA node pacemaker cells can autonomously depolarize, triggering an action potential that leads to the...
The pacemaker cells are located in two primary nodes: the sinoatrial (SA) node and the atrioventricular (AV) node. The SA node pacemaker cells can autonomously depolarize, triggering an action potential that leads to the...
01:29Disturbances in Heart Rhythm
Arrhythmia or dysrhythmia refers to an abnormal heart rhythm caused by a defect in the heart's conduction system. It can cause the heart to beat irregularly, too quickly, or too slowly, leading to symptoms like chest pain, shortness of breath, and fainting. Factors such as stress, caffeine, alcohol, nicotine, cocaine, certain drugs, congenital defects, diseases, and electrolyte abnormalities can trigger arrhythmias.
Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
01:30Cardiac Action Potential
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Ionic Basis of Cardiac Action Potentials
The cardiac action potential process involves a series of phases characterized by the movement of ions across the cardiac cell membranes, leading to the depolarization and repolarization of the cardiac myocytes.
Ionic Basis of Cardiac Action Potentials
01:18Dysrhythmias IV: Characteristics of Bradyarrhythmias
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