胎児における肺静脈流動の動態とその血管直径との関連性
Paulo Zielinsky1, Antônio Piccoli, Eduardo Gus
1Fetal Cardiology Unit, Institute of Cardiology of Rio Grande do Sul, Porto Alegre, Brazil. pesquisa@cardnet.tche.br
Circulation
|October 15, 2003
まとめ
胎児肺静脈脈動性指数 (PVPI) は静脈直径が増加するにつれて減少します. 精度の高いドップラー検体容量の配置は,胎児の肺静脈流動の動態を評価する上で極めて重要です.
科学分野:
- 胎児心臓病の心臓病学について
- 医学画像検査 医学画像検査
- ヘモダイナミクス (血動力学)
背景:
- 胎児肺静脈の流れを評価するには,通常,静脈のディスタル,より広い部分のドップラーサンプルボリュームを使用します.
- 肺静脈脈動性指数 (PVPI) と血管直径の関係が十分に確立されていない.
研究 の 目的:
- 胎児の肺静脈脈動性指数 (PVPI) と肺静脈直径の関連性を調査する.
- 胎児肺静脈評価におけるドップラーサンプル容量の最適な位置づけを決定する.
主な方法:
- 23人の正常な胎児 (平均妊娠年齢28.6週間) を研究するために,ドップラーエコーカルディオグラフィを使用した.
- 肺静脈の流れは近辺と遠辺の位置で評価されました.
- 肺静脈直径は,パワードップラーによる2Dエコーカルディオグラフィを用いて測定した.
- PVPIは (ピークシストリックまたはダイアストリック速度 - プレシストリック速度) /平均速度.
主要な成果:
- 平均遠肺静脈直径 (0.33cm) は近隣直径 (0.16cm) よりも大幅に大きかった.
- 平均遠隔PVPI (0.84) は近接PVPI (2.09) よりも有意に低かった.
- 肺静脈直径とPVPI (P<0.0001) の間には非常に有意な逆指数関数が認められた.
結論:
- 正常な胎児では,肺静脈流の脈動性が肺から心臓に低下します.
- PVPIは肺静脈直径と逆相関しており,直径は遠距離で増加する.
- 正確なドップラーサンプル容量の位置付けは,肺静脈流の正確な評価に不可欠です.
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