Clinical Study On Evaluating The Function Of Cardiac Reserve In Hypertensive Patients With Noninvasive Techniques

Hypertension is one major cardiovascular disease,which usually causes the impairment of target organs,especially heart.The decrease of function of cardiac reserve emerges earlier than disturbance of myocardial systolic and diastolic function.Tt is helpful for the treatment of hypertension to detect the changes of cardiac reserve with noninvasive methods.Objective: to explore whether phonocardiogram exercise test(PCGET), or doppler echocardiography can sensitively and specifically detect the changes of cardiac reserve in patients with hypertesion and whether there is a colse relationship between the two methods.Methods: The trail was performed with eighty volunteers,including twenty healthy persons as control group,and sixty hypertensive patients,which were divided into three subgroups:hypertension A,HA(patients without LVH and enlarged left ventricle);hypertension B,HB(patients with only LVH) and hypertension C,HC(patients with both LVH and enlarged left ventricle).The cardiac contractility reserve index(CCRI) was measured by PCGET,while the value of LV end-systolic and end -diastolic long and short axis dimensions,wall thickness and synchrornous blood pressure were measured by the technique of simultaneous screen display of electrocardiography and synchronously monitoring blood pressure.According to the parameters measured by the latter technique,the values of maximum elasticity(Emax),the average maximum myocardial elasticity stiffness (maxEav) and ejection blood fraction (EF) were calculated by computer programmed process. Results: 1. Compared with control group,there was a statistically significant difference between the hypertension groups except HA group,and also an obvious difference between HB and HC about the indexes of Emax,maxEav and EF(P<0.05). 2.There was a significant difference both between the all hypertension groups in comparison with control group and between three hypertension groups about CCRI(P<0.01). 3.There was a positive correlation between CCRI and Emax,maxEav and EF(P<0.01).Conclusions: 1. CCRI ,Emax,maxEav and EF can all reflect the decrease of cardiac reserve in hypertensive patients. 2.PCGET maybe more sensitively reveal the impairment of cariac reserve in the beginning phase of hypertension than doppler echocardiography.