Development of Low-Invasive Estimation System of Maximum Ventricular Elastance Emax Under Assisted Circulation

辅助循环下最大心室弹性Emax低创估算系统的研制

• 批准号: 09680841
• 负责人: YOSHIZAWA Makoto
• 金额: $ 2.5万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09680841/
• 关键词: Emax; maximum ventricular elastance; estimation; low-invasive; assisted circulation; cardiac function; Ees; inverse problem; E_<max>

The maximum ventricular elastance (Emax) will be a good quantitative index for weaning the patient from the ventricular assist device if the Emax can be obtained low-invasively. The purpose of this research was to develop a method for estimating the Emax beat-to-beat and less-invasively.First, it was formulated that the process for estimating the Emax is a kind of inverse problem. This leaded to an algorithm for estimating the Emax beat-to-beat on the basis of only two measurements : ventricular pressure and ventricular volume or aortic flow.Second, the algorithm was implemented on a personal computer system to calculate Emax in a real-time fashion.Third, the animal experiments using goats were carried out in many situations with change in preload and afterload or with injections for changing cardiac function. The data obtained from the experiments)showed that the correlation coefficient of the Emax between the proposed method and the traditional method was about 0.9. This indicates that the proposed method is sufficiently useful for monitoring cardiac function. Furthermore, it could be shown that the proposed method is superior to the traditional methods because the estimation error can be evaluated quantitatively as an error with respect to the intercept of the end-systolic pressure volume regression line.To apply the proposed method to actual clinical settings, the proposed method must be further improved so that another less-invasive information like aortic pressure instead of ventricular pressure can be used for estimating the Emax.

如果可以低侵入性地获得最大心室弹性（Emax），那么最大心室弹性（Emax）将是患者脱离心室辅助装置的良好定量指标。本研究的目的是开发一种逐搏估计Emax的方法，且侵入性较小。首先，提出估计Emax的过程是一种逆问题。这就产生了一种仅基于两个测量值来估计 Emax 逐搏的算法：心室压力和心室容积或主动脉流量。其次，该算法在个人计算机系统上实现，以实时计算 Emax第三，使用山羊进行的动物实验在多种情况下进行，改变前负荷和后负荷或通过注射改变心脏功能。实验数据表明，本文方法与传统方法的Emax相关系数约为0.9。这表明所提出的方法对于监测心脏功能足够有用。此外，可以表明，该方法优于传统方法，因为估计误差可以定量评估为相对于收缩末压体积回归线的截距的误差。将所提出的方法应用于实际临床设置中，所提出的方法必须进一步改进，以便可以使用另一种侵入性较小的信息（如主动脉压而不是心室压）来估计 Emax。

项目成果

吉澤誠: "総論:生体循環系の推定と制御" 計測と制御. 38・5印刷中. (1999)

Makoto Yoshizawa：“概述：生物循环系统的估计和控制”测量与控制 38/5（1999 年）。

田中明: "人工心臓用適応制御系の同定能力と安定性の評価" 人工臓器. 26・1. 114-118 (1997)

Akira Tanaka：“人工心脏自适应控制系统的识别能力和稳定性评估”Artificial Organs 114-118（1997）。

Makoto Yoshizawa: "An approach to single-bert estimation of Emax as an inverse problem" Proc.of 20th,Annu.Int.Conf.of IEEE Eng.in Med.Biology Soc.379-382 (1998)

Makoto Yoshizawa：“一种将 Emax 的单 bert 估计作为反问题的方法”Proc.of 20th，Annu.Int.Conf.of IEEE Eng.in Med.Biology Soc.379-382 (1998)

M.Yoshizawa: "Classical but effective techniques for estimating cardiovascular dynamics" IEEE Eng.in Med.and Biol.Magazine. 16 (5). 106-112 (1997)

M.Yoshizawa：“评估心血管动态的经典而有效的技术”IEEE Eng.in Med.and Biol.Magazine。

Makoto Yoshizawa: "Heart Replacement-Artificial Heart 6 (T.Akutsu ed.)" Springer-Verlag, 521 (1998)

Makoto Yoshizawa：“心脏置换-人工心脏 6（T.Akutsu 编辑）”Springer-Verlag，521（1998）