PROBLEM TO BE SOLVED: To provide a pulse wave analyzer by which the converging times of reflected waves can be extracted and thereby the indices useful for diagnosing cardiac disease can be calculated out.SOLUTION: In the pulse wave analyzer, the maximum point of the quartic differentiation wave of one pulse wave is obtained (S301) and the maximum point (P2 point) of the reflected wave in which the maximum point of the maximum points of the quartic differentiation present in the interval of the original waveform is one of the characteristic points is determined as the start point of the reflected wave interval which is the first characteristic point (S303). The time point when an amplitude reaches a threshold value after the point is determined as the finish point of the reflected wave interval which is the second characteristic point (S305), wherein 10% of the amplitude of the first characteristic point is a threshold value. The continuous time of the reflected wave which is the time between the first characteristic point and the second characteristic point is calculated out as the index useful for diagnosing the cardiac disease.COPYRIGHT: (C)2010,JPO&INPIT【課題】反射波の収束時間を抽出し、心疾患の診断に有用な指標を算出できる脈波解析装置を提供する。【解決手段】 脈波解析装置では、1拍の脈波の4次微分波の極大点が取得され(S301)、元波形の区間に存在する4次微分の極大点のうち、最大点が特徴点の1つである反射波の最大点(P2点)が、第1の特徴点である反射波区間の開始点に決定される(S303)。第1の特徴点の振幅の10%をしきい値として、当該点以降で振幅が当該しきい値に達した時点が、第2の特徴点である反射波区間の終了点に決定される(S305)。第1の特徴点と第2の特徴点との間の時間である反射波の継続時間が、心疾患の診断に有用な指標として算出される。【選択図】図11
