Enhanced external counterpulsation(EECP)is able to treat myocardial ischemia,which is usually caused by coronary artery stenosis.However,the underlying mechanisms regarding why this technique is effective in treating ...Enhanced external counterpulsation(EECP)is able to treat myocardial ischemia,which is usually caused by coronary artery stenosis.However,the underlying mechanisms regarding why this technique is effective in treating myocardial ischemia remains unclear and there is no patient-specific counterpulsation mode for different rates of coronary artery stenosis in clinic.This study sought to investigate the hemodynamic effect of varied coronary artery stenosis rates when using EECP and the necessity of adopting targeted counterpulsation mode to consider different rates of coronary artery stenosis.Three 3-dimensional(3D)coronary models with different stenosis rates,including 55%(Model 1),65%(Model 2),and 75%(Model 3),were generated,then coupled with a 0-dimensional(0D)lumped parametric model of the blood circulatory system.EECP was applied to the 0D/3D coupled models to study the hemodynamic response of the coronary artery.Under the same counterpulsation mode,the ratio of diastolic blood pressure to systolic blood pressure of 3 models during counterpulsation was 1.4,and the cardiac output and coronary artery flow rate increased significantly.The low wall shear stress(WSS)and high oscillatory shear index(OSI)areas were mainly located at the posterior end of the stenosis and coronary artery bifurcation.Moreover,with an increase in the rate of coronary artery stenosis,the increased percentage of flow rate through the coronary artery stenosis and area-averaged WSS decreased.The geometric multiscale model in this study can be used to effectively simulate the hemodynamic characteristics of cardiovascular system following the application of EECP.Local precise hemodynamic effect of the coronary artery stenosis can be observed.It was found from the hemodynamic factors that the coronary artery with lower stenosis rate more likely led to better vascular endothelial remodeling.Thus,it is necessary to adopt patient-specific counterpulsation mode accounting for different condition of coronary artery stenosis.展开更多
Introduction In the United States, there are about 17.6 million patients suffer from symptomatic coronary artery disease （CAD）, affecting 7.9% of adults ≥ 20 years of age.1 An estimated 10.2 million patients have ...Introduction In the United States, there are about 17.6 million patients suffer from symptomatic coronary artery disease （CAD）, affecting 7.9% of adults ≥ 20 years of age.1 An estimated 10.2 million patients have angina, and 500,000 patients will develop new angina pectoris each year. 1 A subset of angina patients are categorized as refractory when symptoms continue despite optimal medical therapy and revascularization.Routine daily activities become impossible without experiencing chest pain in this patient population.2展开更多
Objective To examine if the skin microvascular bed is altered and can be modified by enhanced external counterpulsation(EECP)in patients with chronic refractory angina.Methods Twenty patients diagnosed with refractory...Objective To examine if the skin microvascular bed is altered and can be modified by enhanced external counterpulsation(EECP)in patients with chronic refractory angina.Methods Twenty patients diagnosed with refractory angina were divided into EECP(n=10)or no EECP(n=10)groups.The data were compared to matched healthy subjects(n=20).The cutaneous forearm microvascular blood flow was measured by Laser-Doppler flowmetry.The vascular responsiveness to iontophoretic administration of acetylcholine(ACh),sodium nitroprusside(SNP)and local skin warming were studied.Measurements of Canadian Cardiovascular Society(CCS)-class,blood pressure and plasma samples were registered.Results EECP patients showed reduced CCS-class compared to no EECP(P<0.05).Both EECP and no EECP(P<0.05)groups had decreased systolic blood pressure(SBP)as compared to SBP at baseline(P<0.05).There was no difference in resting blood flow between the two refractory groups at baseline as well as after EECP and seven weeks of follow-up.Responses to heating,the responses to ACh and SNP in the cutaneous microcirculation were lower in both groups of refractory angina patients as compared to healthy subjects(P<0.05).EECP patients corresponded positively to the treatment shown by reduced plasma level of soluble interleukin-2 receptor and CCS-class.Conclusions Refractory angina patients have reduced responsiveness in their cutaneous microcirculation to ACh,SNP and heat compared to healthy subjects.Although EECP reduced the CCS-class,this effect was not associated with improvements in responsiveness of the cutaneous microcirculation.展开更多
Background Enhanced external counterpulsation （EECP） improves ischemia in patients with refractory angina pectoris but the mechanism remains unclear. To explore the mechanisms of EECP action, we detected progenitor ...Background Enhanced external counterpulsation （EECP） improves ischemia in patients with refractory angina pectoris but the mechanism remains unclear. To explore the mechanisms of EECP action, we detected progenitor cells presenting any of the following markers CD34^＋, CD29^＋, and CD106^＋. Methods Growth cytokines-mediated progenitor cell mobilization and associated angiogenesis potential were assessed in a porcine model of hypercholesterolemia. Twenty-four male domestic swines were randomly assigned to 4 groups： normal diet （control, n=6）, hypercholesterolemic diet （CHOL, n=-6）, hypercholesterolemic diet with administration of recombinant human granulocyte colony-stimulating factor （rhG-CSF） （rhG-CSF, n=6）, and hypercholesterolemic diet with EECP treatment （EECP, n=6）. EECP was applied 2 hours every other day for a total of 36 hours. Serum levels of vascular endothelial growth factor （VEGF） and granulocyte colony-stimulating factor （G-CSF）, peripheral blood progenitor cell counts, level of regional angiogenesis, and expression of VEGF and stromal cell derived factor l a （SDF-1α） in porcine myocardium were assessed, respectively. Results A porcine model of hypercholesterolemia-induced arteriosclerosis was successfully established. There was no significant difference in serum levels of VEGF among the four groups. The serum levels of G-CSF in the EECP group increased significantly at week 15 and week 18 （（38.3±5.6） pg/ml at week 15 vs （26.2±3.7） pg/ml at week 12, P 〈0.05, and （46.9±6.1） pg/ml at week 18 vs （26.2±3.7） pg/ml at week 12, P 〈0.01）. The serum levels of G-CSF in group 3 increased also significantly after receiving rhG-CSF injection for five days （（150±13.9） pg/ml at week 18 vs （24.8±5.4） pg/ml at week 12, P 〈0.01）. Compared to other groups and other time points, progenitor celt counts increased significantly after 2-hour EECP treatment （108±13 vs 26±6 per 10^5 leukocytes, P 〈0.01）, but not at week 18. The progenitor cell counts also increased significantly after subcutaneous injection of rhG-CSF for five days compared to the week 12 （baseline） （180±21 vs 25±7 per 10s leukocytes, P 〈0.01）. There was no significant difference among the four groups at other time points. Moreover, the expression of VEGF and SDF-1α and the level of regional angiogenesis in myocardium increased significantly in both EECP and rhG-CSF groups. Conclusions The results demonstrated that EECP could facilitate angiogenesis in the myocardium of atherosclerotic swines by increasing endogenous G-CSF, inducing an enhanced mobilization of progenitor cells and augmenting myocardial expression of VEGF and SDF-1α.展开更多
Enhance extemal counterpulsation （ECP） procedure has exhbited itself to be an effective therapy for the m anagem entof ischem ic card iovascu lar diseases, However, considering that EECP significantly increases the...Enhance extemal counterpulsation （ECP） procedure has exhbited itself to be an effective therapy for the m anagem entof ischem ic card iovascu lar diseases, However, considering that EECP significantly increases the acute diastolic pressure, whether it will intervene in the chronic progression of advanced plaque causing great concern in clilical applkation, but yet rein ains elusive presently. In the current paper, a flu id-structure interface （FSI） num erical model of artery with p iaque corn ponent w as developed based on in vivo hem odynam ic m easurem entperfotm ed h a porcine model, to caku late the m echanical stresses of the plaque before and during EECP, and h lum to assess the potential effects of long-term EECP treatm ent on plaque progression. The resu Its show that E E C P augm ented the wall shear stress （WSS） and plaque w all stress （PWS） over the card lac cycles, aswell as the spacial oscillatory of W SS （WSSG ）. Durhg EECP treatm ent, the PW S level respectively raised 6.82% and 6.07% in two simulation cases. The currentpilot study suggests that E E C P treatm entre ay p lay a positive effect on inh biting the conthued plaque progression by hcreashg the PW S level over the card iac cycles. Meanwhile, the plaque morphology should be taken into consideration while m aking patient- specific plan for Ion g- term E E C P treatment in clinic.展开更多
Background Coronary slow flow（CSF） during primary percutaneous coronary intervention（PCI） is closely related to the prognosis of patients with acute myocardial infarction（AMI）. Whether Enhanced External CounterP...Background Coronary slow flow（CSF） during primary percutaneous coronary intervention（PCI） is closely related to the prognosis of patients with acute myocardial infarction（AMI）. Whether Enhanced External CounterPulsation（EECP） could improve the phenomenon and enhance cardiac function in these patients has not been studied. Methods Seventy-eight AMI patients undergoing primary PCI were enrolled and divided into 2 groups, EECP group and sham group. In EECP group, the patients were treated with EECP for 30 min after coronary artery stent implantation; and in sham group, the patients after coronary artery stent implantation were treated with cuffs wrapped for 30 min. Hemodynamics and corrected TIMI Frame Count（c TFC） were recorded at different time points in both groups. CRP, HCY, NT-pro BNP and Killip class were also detected before operation and after treatment. Results In EECP group, compared to pre-and post-EECP treatment, the systolic blood pressure（SBP） was much lower（P〈0.05）, diastolic blood pressure（DBP） and mean arterial blood pressure（MBP）were much higher（P〈0.05）. The heart rate（HR） was not changed during EECP treatment（P〉0.05）. In sham group, SBP, DBP, MBP and HR were not significantly changed during these period（P〉0.05）. In EECP group,the c TFC of patients with CSF decreased significantly after treatment（P〈0.05）; and there was no difference in sham group（P〉0.05）. Compared with pre-EECP treatment, CRP and HCY were increased in post-EECP treatment of both groups（P〈0.05）, while, they were much lower in EECP group（P〈0.05）. The expression of NTpro BNP was decreased after treatment in both groups（P〈0.05）, and it was much lower in EECP group than in sham group（P〈0.05）. The Killip class was much lower after treatment than before operation in EECP group（P〈0.05）, and there was no change in sham group（P〉0.05）. Conclusions The results suggest that EECP is helpful in a short time to the improvement of CSF and recovery of cardiac function in AMI patients during primary PCI,and that CRP and HCY may be involved in this process.展开更多
To make clear the precise hemodynamic mechanism underlying the anti-atherogenesis benefit of enhanced external couterpulsation(EECP) treatment, and to investigate the proper role of some important hemodynamic factors ...To make clear the precise hemodynamic mechanism underlying the anti-atherogenesis benefit of enhanced external couterpulsation(EECP) treatment, and to investigate the proper role of some important hemodynamic factors during the atherosclerotic progress, a comprehensive study combining long-term animal experiment and numerical solving was conducted in this paper. An experimentally induced hypercholesterolemic porcine model was developed and the chronic EECP intervention was subjected. Basic hemodynamic measurement was performed in vivo, as well as the arterial endothelial samples were extracted for physiological examination. Meanwhile, a numerical model was introduced to solve the complex hemodynamic factors such as WSS and OSI. The results show that EECP treatment resulted in significant increase of the instant levels of arterial WSS, blood pressure, and OSI. During EECP treatment, the instant OSI level of the common carotid arteries over cardiac cycles raised to a mean value of 8.58 ×10-2±2.13 ×10-2. Meanwhile, the chronic intervention of EECP treatment significantly reduced the atherosclerotic lesions in abdominal aortas and the endothelial cellular adherence. The present study suggests that the unique blood flow pattern induced by EECP treatment and the augmentation of WSS level in cardiac cycles may be the most important hemodynamic mechanism that contribute to its anti-atherogenesis effect. And as one of the indices that cause great concern in current hemodynamic study, OSI may not play a key role during the initiation of atherosclerosis.展开更多
Objective To explore the effects of enhanced external counterpulsation(EECP)on the serum level of C-reactive protein and endothelin-1 in patients with cerebral ischemic stroke,to provide clinical evidence for the trea...Objective To explore the effects of enhanced external counterpulsation(EECP)on the serum level of C-reactive protein and endothelin-1 in patients with cerebral ischemic stroke,to provide clinical evidence for the treatment and secondary prevention of patients with serebral ischemic stroke.Methods Total 187 patients with ischemic stroke and enrolled measure the serum level展开更多
基金This research was supported by National Natural Science Foundation of China(11772016,11472022,11702008)Key Project of Science and Technology of Beijing Municipal Education Commission and Support Plan for High-level Faculties in Beijing Municipal Universities(CIT&TCD201804011).
文摘Enhanced external counterpulsation(EECP)is able to treat myocardial ischemia,which is usually caused by coronary artery stenosis.However,the underlying mechanisms regarding why this technique is effective in treating myocardial ischemia remains unclear and there is no patient-specific counterpulsation mode for different rates of coronary artery stenosis in clinic.This study sought to investigate the hemodynamic effect of varied coronary artery stenosis rates when using EECP and the necessity of adopting targeted counterpulsation mode to consider different rates of coronary artery stenosis.Three 3-dimensional(3D)coronary models with different stenosis rates,including 55%(Model 1),65%(Model 2),and 75%(Model 3),were generated,then coupled with a 0-dimensional(0D)lumped parametric model of the blood circulatory system.EECP was applied to the 0D/3D coupled models to study the hemodynamic response of the coronary artery.Under the same counterpulsation mode,the ratio of diastolic blood pressure to systolic blood pressure of 3 models during counterpulsation was 1.4,and the cardiac output and coronary artery flow rate increased significantly.The low wall shear stress(WSS)and high oscillatory shear index(OSI)areas were mainly located at the posterior end of the stenosis and coronary artery bifurcation.Moreover,with an increase in the rate of coronary artery stenosis,the increased percentage of flow rate through the coronary artery stenosis and area-averaged WSS decreased.The geometric multiscale model in this study can be used to effectively simulate the hemodynamic characteristics of cardiovascular system following the application of EECP.Local precise hemodynamic effect of the coronary artery stenosis can be observed.It was found from the hemodynamic factors that the coronary artery with lower stenosis rate more likely led to better vascular endothelial remodeling.Thus,it is necessary to adopt patient-specific counterpulsation mode accounting for different condition of coronary artery stenosis.
文摘Introduction In the United States, there are about 17.6 million patients suffer from symptomatic coronary artery disease （CAD）, affecting 7.9% of adults ≥ 20 years of age.1 An estimated 10.2 million patients have angina, and 500,000 patients will develop new angina pectoris each year. 1 A subset of angina patients are categorized as refractory when symptoms continue despite optimal medical therapy and revascularization.Routine daily activities become impossible without experiencing chest pain in this patient population.2
文摘Objective To examine if the skin microvascular bed is altered and can be modified by enhanced external counterpulsation(EECP)in patients with chronic refractory angina.Methods Twenty patients diagnosed with refractory angina were divided into EECP(n=10)or no EECP(n=10)groups.The data were compared to matched healthy subjects(n=20).The cutaneous forearm microvascular blood flow was measured by Laser-Doppler flowmetry.The vascular responsiveness to iontophoretic administration of acetylcholine(ACh),sodium nitroprusside(SNP)and local skin warming were studied.Measurements of Canadian Cardiovascular Society(CCS)-class,blood pressure and plasma samples were registered.Results EECP patients showed reduced CCS-class compared to no EECP(P<0.05).Both EECP and no EECP(P<0.05)groups had decreased systolic blood pressure(SBP)as compared to SBP at baseline(P<0.05).There was no difference in resting blood flow between the two refractory groups at baseline as well as after EECP and seven weeks of follow-up.Responses to heating,the responses to ACh and SNP in the cutaneous microcirculation were lower in both groups of refractory angina patients as compared to healthy subjects(P<0.05).EECP patients corresponded positively to the treatment shown by reduced plasma level of soluble interleukin-2 receptor and CCS-class.Conclusions Refractory angina patients have reduced responsiveness in their cutaneous microcirculation to ACh,SNP and heat compared to healthy subjects.Although EECP reduced the CCS-class,this effect was not associated with improvements in responsiveness of the cutaneous microcirculation.
基金This study was supported by grants from tile China National 10th Five-year Key Research Project of Science （No. 2001BA706B-07） and National Natural Science Foundation of China （No. 30127001）.Acknowledgement： The authors would like to thank FAN Dian-qiu, FENG Min-zhe, LIN Gui-fan, QIAN Yue-tao, DAI Gang and LIAN Lu-guang for their technical supports.
文摘Background Enhanced external counterpulsation （EECP） improves ischemia in patients with refractory angina pectoris but the mechanism remains unclear. To explore the mechanisms of EECP action, we detected progenitor cells presenting any of the following markers CD34^＋, CD29^＋, and CD106^＋. Methods Growth cytokines-mediated progenitor cell mobilization and associated angiogenesis potential were assessed in a porcine model of hypercholesterolemia. Twenty-four male domestic swines were randomly assigned to 4 groups： normal diet （control, n=6）, hypercholesterolemic diet （CHOL, n=-6）, hypercholesterolemic diet with administration of recombinant human granulocyte colony-stimulating factor （rhG-CSF） （rhG-CSF, n=6）, and hypercholesterolemic diet with EECP treatment （EECP, n=6）. EECP was applied 2 hours every other day for a total of 36 hours. Serum levels of vascular endothelial growth factor （VEGF） and granulocyte colony-stimulating factor （G-CSF）, peripheral blood progenitor cell counts, level of regional angiogenesis, and expression of VEGF and stromal cell derived factor l a （SDF-1α） in porcine myocardium were assessed, respectively. Results A porcine model of hypercholesterolemia-induced arteriosclerosis was successfully established. There was no significant difference in serum levels of VEGF among the four groups. The serum levels of G-CSF in the EECP group increased significantly at week 15 and week 18 （（38.3±5.6） pg/ml at week 15 vs （26.2±3.7） pg/ml at week 12, P 〈0.05, and （46.9±6.1） pg/ml at week 18 vs （26.2±3.7） pg/ml at week 12, P 〈0.01）. The serum levels of G-CSF in group 3 increased also significantly after receiving rhG-CSF injection for five days （（150±13.9） pg/ml at week 18 vs （24.8±5.4） pg/ml at week 12, P 〈0.01）. Compared to other groups and other time points, progenitor celt counts increased significantly after 2-hour EECP treatment （108±13 vs 26±6 per 10^5 leukocytes, P 〈0.01）, but not at week 18. The progenitor cell counts also increased significantly after subcutaneous injection of rhG-CSF for five days compared to the week 12 （baseline） （180±21 vs 25±7 per 10s leukocytes, P 〈0.01）. There was no significant difference among the four groups at other time points. Moreover, the expression of VEGF and SDF-1α and the level of regional angiogenesis in myocardium increased significantly in both EECP and rhG-CSF groups. Conclusions The results demonstrated that EECP could facilitate angiogenesis in the myocardium of atherosclerotic swines by increasing endogenous G-CSF, inducing an enhanced mobilization of progenitor cells and augmenting myocardial expression of VEGF and SDF-1α.
基金Key Clinical Project from the Ministry of Heatthgrant number:25400+1 种基金National Natural Science Foundation of Chinagrant number:81170272
文摘Enhance extemal counterpulsation （ECP） procedure has exhbited itself to be an effective therapy for the m anagem entof ischem ic card iovascu lar diseases, However, considering that EECP significantly increases the acute diastolic pressure, whether it will intervene in the chronic progression of advanced plaque causing great concern in clilical applkation, but yet rein ains elusive presently. In the current paper, a flu id-structure interface （FSI） num erical model of artery with p iaque corn ponent w as developed based on in vivo hem odynam ic m easurem entperfotm ed h a porcine model, to caku late the m echanical stresses of the plaque before and during EECP, and h lum to assess the potential effects of long-term EECP treatm ent on plaque progression. The resu Its show that E E C P augm ented the wall shear stress （WSS） and plaque w all stress （PWS） over the card lac cycles, aswell as the spacial oscillatory of W SS （WSSG ）. Durhg EECP treatm ent, the PW S level respectively raised 6.82% and 6.07% in two simulation cases. The currentpilot study suggests that E E C P treatm entre ay p lay a positive effect on inh biting the conthued plaque progression by hcreashg the PW S level over the card iac cycles. Meanwhile, the plaque morphology should be taken into consideration while m aking patient- specific plan for Ion g- term E E C P treatment in clinic.
基金supported by Science and Technology Planning project of Guangdong Province(No.2012A03220005)
文摘Background Coronary slow flow（CSF） during primary percutaneous coronary intervention（PCI） is closely related to the prognosis of patients with acute myocardial infarction（AMI）. Whether Enhanced External CounterPulsation（EECP） could improve the phenomenon and enhance cardiac function in these patients has not been studied. Methods Seventy-eight AMI patients undergoing primary PCI were enrolled and divided into 2 groups, EECP group and sham group. In EECP group, the patients were treated with EECP for 30 min after coronary artery stent implantation; and in sham group, the patients after coronary artery stent implantation were treated with cuffs wrapped for 30 min. Hemodynamics and corrected TIMI Frame Count（c TFC） were recorded at different time points in both groups. CRP, HCY, NT-pro BNP and Killip class were also detected before operation and after treatment. Results In EECP group, compared to pre-and post-EECP treatment, the systolic blood pressure（SBP） was much lower（P〈0.05）, diastolic blood pressure（DBP） and mean arterial blood pressure（MBP）were much higher（P〈0.05）. The heart rate（HR） was not changed during EECP treatment（P〉0.05）. In sham group, SBP, DBP, MBP and HR were not significantly changed during these period（P〉0.05）. In EECP group,the c TFC of patients with CSF decreased significantly after treatment（P〈0.05）; and there was no difference in sham group（P〉0.05）. Compared with pre-EECP treatment, CRP and HCY were increased in post-EECP treatment of both groups（P〈0.05）, while, they were much lower in EECP group（P〈0.05）. The expression of NTpro BNP was decreased after treatment in both groups（P〈0.05）, and it was much lower in EECP group than in sham group（P〈0.05）. The Killip class was much lower after treatment than before operation in EECP group（P〈0.05）, and there was no change in sham group（P〉0.05）. Conclusions The results suggest that EECP is helpful in a short time to the improvement of CSF and recovery of cardiac function in AMI patients during primary PCI,and that CRP and HCY may be involved in this process.
基金Key Clinical Project from the Ministry of Healthgrant number:25400+1 种基金National Natural Science Foundation of Chinagrant number:81170272
文摘To make clear the precise hemodynamic mechanism underlying the anti-atherogenesis benefit of enhanced external couterpulsation(EECP) treatment, and to investigate the proper role of some important hemodynamic factors during the atherosclerotic progress, a comprehensive study combining long-term animal experiment and numerical solving was conducted in this paper. An experimentally induced hypercholesterolemic porcine model was developed and the chronic EECP intervention was subjected. Basic hemodynamic measurement was performed in vivo, as well as the arterial endothelial samples were extracted for physiological examination. Meanwhile, a numerical model was introduced to solve the complex hemodynamic factors such as WSS and OSI. The results show that EECP treatment resulted in significant increase of the instant levels of arterial WSS, blood pressure, and OSI. During EECP treatment, the instant OSI level of the common carotid arteries over cardiac cycles raised to a mean value of 8.58 ×10-2±2.13 ×10-2. Meanwhile, the chronic intervention of EECP treatment significantly reduced the atherosclerotic lesions in abdominal aortas and the endothelial cellular adherence. The present study suggests that the unique blood flow pattern induced by EECP treatment and the augmentation of WSS level in cardiac cycles may be the most important hemodynamic mechanism that contribute to its anti-atherogenesis effect. And as one of the indices that cause great concern in current hemodynamic study, OSI may not play a key role during the initiation of atherosclerosis.
文摘Objective To explore the effects of enhanced external counterpulsation(EECP)on the serum level of C-reactive protein and endothelin-1 in patients with cerebral ischemic stroke,to provide clinical evidence for the treatment and secondary prevention of patients with serebral ischemic stroke.Methods Total 187 patients with ischemic stroke and enrolled measure the serum level
