左心室の幾何学と機能は,神経媒介性シンコープの前である
1Department of Medicine, Division of Cardiology, The New York Hospital-Cornell Medical Center, New York, NY 10021, USA.
Circulation
|February 23, 2000
まとめ
神経媒介性失眠は,左心室 (LV) の収縮性の増加によって引き起こされません. 垂直傾斜時のLV機能と体積の低下は,シンコープ患者における傾斜テーブルテストの陽性反応と関連しています.
科学分野:
- 心臓病学 心臓病学
- 生理学 生理学とは
背景:
- 神経媒介性昏睡は,傾斜テスト中に左心室 (LV) の小分縮小 (FS) の増加と関連しています.
- これは,LV機構受容体刺激が反射性低血圧を引き起こすことを示唆しますが,FSは,収縮性だけでなく,後負荷と前負荷の影響を受けます.
研究 の 目的:
- 神経媒介性昏睡におけるLV収縮性の役割を調査する.
- エンドシストリックストレス (ESS) に調整されたLVパフォーマンスの測定値を,ポジティブとネガティブな傾斜テーブルテストの応答を持つ患者で比較する.
主な方法:
- エコーカルディオグラフィは,横たわり,直立した傾斜の姿勢で原因不明のシンコープを患った21人の患者のLVパフォーマンスを評価するために使用されました.
- ストローク容量,FS,およびストレスの調整による中壁の縮小を含むLV測定は,傾斜陽性および傾斜陰性グループ間で比較されました.
主要な成果:
- 横になった状態では,両グループは同様のLVパフォーマンスを示しました.
- 垂直傾斜の間,傾斜陽性グループは,より低いストローク容量,ストレス調整による中壁短縮の減少,および心臓内部のFSの減少を示した.
- ティルト・ポジティブグループも,ティルトの初期にESSとFSの減少が顕著であった.
結論:
- 初期直立傾斜時の末期シストリックストレス (ESS),LV容量,および室内機能の減少は,シンコープ患者におけるポジティブな傾斜応答と相関しています.
- これらの発見は,LVの超収縮性またはシストリック壁のストレスの増加が,LVのメカニカル受容体の活性化による神経媒介性シンコープを誘発しないことを示唆しています.
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