为了对心脏疾病的诊断和治疗提供指导,同时也为进行心脏辅助装置的设计及评价提供有利的工具,提出了基于双弹性腔模型和整心动周期脉搏波的血流动力学参数估计方法,运用非线性最小二乘Levenberg-Marqurdt算法对实测脉搏波数据进行参数...为了对心脏疾病的诊断和治疗提供指导,同时也为进行心脏辅助装置的设计及评价提供有利的工具,提出了基于双弹性腔模型和整心动周期脉搏波的血流动力学参数估计方法,运用非线性最小二乘Levenberg-Marqurdt算法对实测脉搏波数据进行参数估计得到动脉系统的模型参数,即人体的血流动力学参数(包括外周阻力、动脉顺应性和血流惯性).利用MATLAB/Simulink工具结合图形用户界面(graphical user interface,GUI)建立的左心与动脉系统耦合的动力学电路模型得到的仿真结果与人体实测脉搏波数据进行对比分析,验证了模型参数估计的有效性.用该方法估计的参数结果符合生理参数范围,且效果优于传统的舒张期估计方法,其中主动脉顺应性参数的估计结果误差降低了50%,参数带入模型得到的仿真结果与实测脉搏波之间的误差也降低了20%左右.展开更多
Objective:To study the effect of Simvastatin on the left ventricular mass and endothelial function and to investigate the relationship between their changes in the patients with essential hypertension(EH). Methods: 5...Objective:To study the effect of Simvastatin on the left ventricular mass and endothelial function and to investigate the relationship between their changes in the patients with essential hypertension(EH). Methods: 50 patients with hypertension without severe complication were divided into two groups in a randomized,controlled and single blind trial.Group I(n=25)were given Simvastatin and hydragogue for 12 weeks while Group Ⅱ were given hydragogue during the same time.We detected the left ventricular mass and the brachial artery dilatation induced by reactive hyperemia(DIRH)or nitroglycerin(DING)respectively with ultrasonography in all patients before and after treatment.25 normal subjects without any treatment were taken as the control. Results:The left ventricular mass index(LVMI)was higher in the two groups of patients[(133.61±31.02)g/m 2;(118.04±39.62)g/m 2]than that in the control(88.79±22.73)g/m 2 before treatment(P<0.01,0.000 1,respectively)while the blood pressure was higher.The DIRH was lower in the two groups of patients(5.93±2.24)%;(6.54±3.16)%than that in the control(13.09±2.99)%,P<0.000 1.There was no significantly differences in age,serum concentrations of total cholesterol,triglyceride,sugar,blood pressure or the DING between two groups of patients and the control(P>0.05).And there was no significant difference in the all variables between group Ⅰ and group Ⅱ before treatment.After treatment the LVMI decreased[(133.61±31.02)g/m 2 VS(91.07±16.01)g/m 2,P<0.01]and the DTRH increased[(5.93±2.24)% VS(13.53±2.38)%,P<0.01]in the patients of group Ⅰ while there was no significant change in LVMI and DIRH in the patients of group Ⅱ.The blood pressure in the two groups of patients was decreased to the normal.Compared with group Ⅱ,the changes of LVMI and DIRH was higher in patients of group Ⅰ though the serum concentrations of total cholesterol,triglyceride or sugar were not significantly different.No significant change in serum concentrations oftotal cholesterol,triglyceride or sugar was found during treatment in the two groups of patients.Analysis showed that the LVMI correlated with DIRH and the change of LVMI correlated better with the change of DIRH(r=-0.56;0.69,P<0.000 1,respectly). Conclusions: The increase of left ventricular mass was related with endothelial dysfunction in essential hypertension.Being independent of the changes of serum concentrations of total cholesterol,triglyceride or sugar and blood pressure,Simvastatin could inhibit the increase of left ventricular mass and improve endothelial function.展开更多
文摘为了对心脏疾病的诊断和治疗提供指导,同时也为进行心脏辅助装置的设计及评价提供有利的工具,提出了基于双弹性腔模型和整心动周期脉搏波的血流动力学参数估计方法,运用非线性最小二乘Levenberg-Marqurdt算法对实测脉搏波数据进行参数估计得到动脉系统的模型参数,即人体的血流动力学参数(包括外周阻力、动脉顺应性和血流惯性).利用MATLAB/Simulink工具结合图形用户界面(graphical user interface,GUI)建立的左心与动脉系统耦合的动力学电路模型得到的仿真结果与人体实测脉搏波数据进行对比分析,验证了模型参数估计的有效性.用该方法估计的参数结果符合生理参数范围,且效果优于传统的舒张期估计方法,其中主动脉顺应性参数的估计结果误差降低了50%,参数带入模型得到的仿真结果与实测脉搏波之间的误差也降低了20%左右.
文摘Objective:To study the effect of Simvastatin on the left ventricular mass and endothelial function and to investigate the relationship between their changes in the patients with essential hypertension(EH). Methods: 50 patients with hypertension without severe complication were divided into two groups in a randomized,controlled and single blind trial.Group I(n=25)were given Simvastatin and hydragogue for 12 weeks while Group Ⅱ were given hydragogue during the same time.We detected the left ventricular mass and the brachial artery dilatation induced by reactive hyperemia(DIRH)or nitroglycerin(DING)respectively with ultrasonography in all patients before and after treatment.25 normal subjects without any treatment were taken as the control. Results:The left ventricular mass index(LVMI)was higher in the two groups of patients[(133.61±31.02)g/m 2;(118.04±39.62)g/m 2]than that in the control(88.79±22.73)g/m 2 before treatment(P<0.01,0.000 1,respectively)while the blood pressure was higher.The DIRH was lower in the two groups of patients(5.93±2.24)%;(6.54±3.16)%than that in the control(13.09±2.99)%,P<0.000 1.There was no significantly differences in age,serum concentrations of total cholesterol,triglyceride,sugar,blood pressure or the DING between two groups of patients and the control(P>0.05).And there was no significant difference in the all variables between group Ⅰ and group Ⅱ before treatment.After treatment the LVMI decreased[(133.61±31.02)g/m 2 VS(91.07±16.01)g/m 2,P<0.01]and the DTRH increased[(5.93±2.24)% VS(13.53±2.38)%,P<0.01]in the patients of group Ⅰ while there was no significant change in LVMI and DIRH in the patients of group Ⅱ.The blood pressure in the two groups of patients was decreased to the normal.Compared with group Ⅱ,the changes of LVMI and DIRH was higher in patients of group Ⅰ though the serum concentrations of total cholesterol,triglyceride or sugar were not significantly different.No significant change in serum concentrations oftotal cholesterol,triglyceride or sugar was found during treatment in the two groups of patients.Analysis showed that the LVMI correlated with DIRH and the change of LVMI correlated better with the change of DIRH(r=-0.56;0.69,P<0.000 1,respectly). Conclusions: The increase of left ventricular mass was related with endothelial dysfunction in essential hypertension.Being independent of the changes of serum concentrations of total cholesterol,triglyceride or sugar and blood pressure,Simvastatin could inhibit the increase of left ventricular mass and improve endothelial function.