利用動脈阻抗分析以量化心室之後負荷

Quantitation and Characterization of Ventricular Afterload by Arterial Impedance Analysis

張國柱(K. C. Chang)；謝凱生(K. C. Hsieh)；郭德盛(T. S. Kuo)；陳幸一(H. I. Chen)

心室後負荷 ； 動脈阻抗 ； 心肌收縮力 ； 頻譜分析 ； 脈波反射 ； Ventricular afterload ； Aortic impedance ； Myoeardical contractility ； Frequency analysis ； Wave reflection

Journal of Medical Sciences

10卷2期（1989 / 04 / 01）

61 - 66

繁體中文

在心臟心管系統領域裡，「後負荷」（afterload）一詞之廣泛定義為：阻礙完整心臟（intact heart）肌纖維收縮之外在因素（external factors）。許多學者曾努力地尋找一種能夠表徵心室收縮狀態（contractile state）的指標，作為評估心室能力（ventricular performance）的依據。而此指標必須不受所有的外在力量（external force）影響，在這外在力量中非常重要的一環，便是心室後負荷（ventricular afterload）。因此，對於完整心室後負荷在運作上的定義（operational definition）是值得加以探討的。本文將討論動脈阻抗（arterial impedance）之頻率相關特性（frequency dependent）及其所涵蘊之反射性質（reflection property），並闡述以動脈阻抗分析量化心室後負荷之緣由及其優點。期望對動脈系統（arterial system）的物理性質有更深一切的認識，為臨床上心臟血管病變之診斷與治療提供良好的依據與參考。

”Afterload” has been broadly defined as the external factors in cardiovascular system that oppose the shorrening of myocardial fibers. Many investigators have been searching for an index of ventricular contractile state in order to evaluate the ventricular performance. The index of contractile state of the ventricle must be independent of all external forces. The ventricular afterload is an important component of the external forces. Thus, it is important to define the afterload of an intact ventricle from the standpoint of real operation. In this article, we discuses the property of frequency dependence of arterial impedance and the implication of wave reflection due to impedance spectrum. We also address the advantage of characterization and quantification of afterload by arterial impedance analysis. The understanding of physical properties of arterial system by frequency analysis may provide valuable information to the physiological and clinical investigation and treatment of cardiovascular diseases.