心臓Pacing時の末梢血行動態

Peripheral hemodynamics and changes of the heart rate caused by cardiac pacing

　ペースメーカー植込み患者にとって，その心拍数が至適であるかいなかということは，血行動態上まことに重要なことである。至適心拍数を決定するパラメーターとしては心拍出量，一回拍出量，心房拍動数，心内圧，動脈圧，心仕事等が用いられ，今までに多くの報告がなされているが，今回著者らは当教室で開発された指血圧測定装置^1），Pneumoplethysmograph FM−10^2〜4）を用い，心疾患患者を対象として心房ペーシング，心室ペーシング時の指血圧，指血流量，指血管抵抗，指動脈コンプライアンス，体血圧，心拍出量，右房圧を測定し，心拍数の変化が末梢血行に与える影響，心房ペーシングと心室ペーシングの相違点および末梢血行からみた至適心拍数について検討し，若干の知見を得たので報告する。

The purpose of this investigation was to evaluate the peripheral hemodynamics during cardiac pacing in adult man. This study was performed in 2 nor-mal subjects and 11 patients with SSS and com-plete AV block. The peripheral parameters, such as digital blood pressure, digital blood flow, digital vascular resistance and compliance of the peripher-al resistance vessels were measured during cardiac pacing which increased the heart rate.

The results were obtained as follows: al Digitalblood pressures (systolic, diastolic and mean) were not changed by the increase of heart rate. b) When the heart rate increased from 50/min to 100(min, digital blood flow increased from 34 to 63 ml, 100ml of tissue min. At the time when the heart rate was more than 100 min, digital blood flow decreased gradually. c) In agreement with in-creasing of the heart rate, peripheral vascular resist-ance decreased remarkably. d) Compliance of the the resistance vessels was decreasing until the heart rate was over 100/min. Compliance of the resistance vessels became constant, just after the heart rate was more than 100/min.