Effects And Mechanism Of Enhanced External Couterpulsation In Hypertensive Patients With Increased Arterial Stiffness

Background Increased arterial stiffness is closely related to the occurrence and development of cardiovascular and cerebrovascular diseases,and is a strong predictor of cardiovascular and cerebrovascular related events.Hypertension is one of the main risk factors causing increased arterial stiffness.The incidence of cardiovascular and cerebrovascular events in hypertensive patients with increased arterial stiffness in China is increasing year by year,and it is younger,seriously threatening people’s health and causing serious burden to families and society.Nowadays,studies have shown that enhanced external counterpulsation(EECP)can reduce arterial stiffness to a certain extent in patients with coronary heart disease,ischemic stroke,etc.However,there is still a lack of research reports on the effects and mechanism of EECP in hypertensive patients with increased arterial stiffness.Objective To investigate the effects of EECP on hypertensive patients with increased arterial stiffness and its possible mechanism.Methods 52 hypertensive patients with increased arterial stiffness were randomly divided into routine treatment group(n=26)and enhanced external counterpulsation treatment group(n=26),also called "EECP group".The routine treatment group maintained the previous therapeutic schedule,and EECP group maintained the previous treatment schedule combined with enhanced external counterpulsation therapy.The standard protocol for external counterpulsation therapy is 1 hour/session,5 sessions/week for 7 consecutive weeks,for a total of 35 sessions.The general clinical data and biochemical examination of the two groups were recorded.The carotid-femoral pulse wave velocity(CfPWV),augmentation index(AIx),nitric oxide,endothelin-1,non-invasive peripheral artery blood pressure and central artery blood pressure were collected before and after treatment.SPSS 23.0 statistical software was used for data analysis and processing,and it was considered statistically significant when P<0.05.Results(1)There were no statistically significant differences in general clinical data and biochemical tests between the two groups,including gender,age,smoking,body mass index,duration of hypertension,heart rate,triglycerides,total cholesterol,low-density lipoprotein cholesterol,high-density lipoprotein cholesterol,serum uric acid,glycosylated hemoglobin,fasting blood glucose,creatinine,glutamic pyruvic transaminase glutamic oxaloacetic transaminase,carotid-femoral pulse wave velocity(CfPWV),augmentation index(AIx),NO,ET-1,peripheral artery blood pressure,central artery blood pressure,and previous medication(P>0.05).(2)Comparison of CfPWV and AIx before and after treatment between the two groups:CfPWV and AIx in the routine treatment group had no significant change after treatment compared with those before treatment,and the difference had no statistical significance(P>0.05).In the EECP treatment group,CfPWV and AIx decreased after treatment compared with those before treatment(CfPWV 10.7±0.4 m/s before treatment vs 10.2±0.3 m/s after treatment;P<0.001)(AIx 34.3±3.0%before treatment vs 28.9±2.7%after treatment;P<0.001).The difference had statistical significance(P<0.05).(3)Comparison of NO and ET-1 before and after treatment between the two groups:NO and ET-1 in the routine treatment group were not significantly changed after treatment compared with those before treatment,and the difference had no statistical significance(P>0.05).In the EECP treatment group,NO increased after treatment compared with that before treatment(32.65±8.67 umol/L before treatment vs 54.73± 13.57 umol/L after treatment;P<0.001),and the difference was statistically significant(P<0.05).ET-1 in the EECP treatment group decreased after treatment compared with that before treatment(51.57±7.83 ng/L before treatment vs 29.31 ±7.45 ng/L after treatment;P<0.001),and the difference was statistically significant(P<0.05).(4)Comparison of peripheral artery blood pressure before and after treatment between the two groups:After treatment,peripheral artery systolic pressure,peripheral artery diastolic pressure,peripheral artery mean pressure and peripheral artery pulse pressure in the routine treatment group had no significant change compared with those before treatment,and the differences had no statistical significance(P>0.05).After treatment,peripheral artery systolic pressure and peripheral artery pulse pressure in EECP treatment group decreased compared with those before treatment(PSBP 137.4±8.3 mmHg before treatment vs 128.7±9.0 mmHg after treatment;P<0.001),(PPP 63.6±11.3 mmHg before treatment vs 53.5±11.2 mmHg after treatment;P<0.001),and the differences had statistical significance(P<0.05).After treatment,peripheral artery diastolic pressure and peripheral artery mean pressure in EECP treatment group had no significant change compared with those before treatment(PDBP before treatment 72.8 ±6.1 mmHg vs 74.2±4.9 mmHg after treatment;P=0.309),(PMAP before treatment 94.8±4.9 mmHg vs 92.9±4.7 mmHg after treatment;P=0.684),and the differences had no statistical significance(P>0.05).(5)Comparison of central arterial blood pressure before and after treatment between the two groups:After treatment,central arterial systolic pressure,central arterial diastolic pressure and central arterial pulse pressure in the routine treatment group had no significant change compared with those before treatment,and the differences had no statistical significance(P>0.05).In the EECP treatment group,the central arterial systolic pressure and central arterial pulse pressure decreased after treatment compared with those before treatment(CSBP 127.5±9.2 mmHg before treatment vs 121.3±8.4 mmHg after treatment;P<0.01),(CPP 54.4±11.9 mmHg before treatment vs 47.7±11.4 mmHg after treatment;P=0.046),and the differences were statistically significant(P<0.05).In the EECP treatment group,central arterial diastolic pressure did not change significantly after treatment compared with that before treatment(CDBP 73.0±6.5 mmHg before treatment vs 73.5±6.6 mmHg after treatment;P=0.785),and the difference was not statistically significant(P>0.05).Conclusion Enhanced external counterpulsation can reduce CfPWV and AIx and improve arterial stiffness in hypertensive patients with increased arterial stiffness;A reduction in systolic blood pressure and pulse pressure and the improvement of vascular endothelial dysfunction may be a potential mechanism of its clinical benefits.