Impact of Enhanced External Counterpulsation on Vascular Hemodynamics and Status

Patients with coronary heart disease will be randomized into two groups: standard medical treatment and standard medical treatment plus EECP intervention. Hemodynamic parameters, vascular status and function will be measured.

• EECP (Device), also known as Enhanced External Counterpulsation: Enhanced external counterpulsation (EECP) is a technique for assisting the circulation by decreasing the afterload of the left ventricle and augmenting the diastolic pressure externally by applying a negative pressure to the lower extremities during cardiac systole. EECP therapy is done by sequential inflation of 3 sets of cuffs wrapped around the lower extremities during diastole and deflation of the cuffs during systole. EECP enhances the aortic diastolic blood flow and coronary perfusion, leading to increased arterial wall shear stress in a pulsatile manner.
• Medical therapy (Drug), also known as Guideline- driven medical therapy: Guideline- driven standard medical treatment including statins,antiplatelet drugs（aspirin or Clopidogrel ）, anti-ischemic drugs （Nitroglycerin）

Primary outcomes

• Change in blood flow velocity [At baseline, during EECP and week 7 (post intervention)]: Change from baseline in blood flow velocity measured by color Doppler ultrasound system

Secondary outcomes

• Change in vascular endothelial function [At baseline and week 7 (post intervention)]: Change from baseline in flow- mediated dilation (FMD) accessed by color Doppler ultrasound system
• Change in atherosclerosis [At baseline and week 7 (post intervention)]: Change from baseline in atherosclerosis : plaque of common carotid artery, carotid intima- media thickness, pulse wave velocity

Sex: All, ages: 20 Years to 80 Years

Inclusion Criteria:

* More than 50% stenosis of left main trunk and 3 epicardial coronary arteries and their large branches showed by coronary angiography
* Or history of myocardial infarction
* Or history of prior revascularization
* Signed informed consent to participate in the study

Exclusion Criteria:

* Clinically significant valvular heart disease
* Aortic aneurysm
* Congenital heart disease
* Acute myocarditis
* Arrythmias significantly interfere with the triggering of the EECP device
* History of cerebral hemorrhage
* Hemorrhagic disease
* Lower limb infection, phlebitis
* Deep venous thrombosis
* Malignant disease
* INR > 2.5
* Uncontrolled hypertension, defined as SBP > 180mmHg or DBP > 110mmHg
* Pregnancy

• Manchanda A, Soran O. Enhanced external counterpulsation and future directions: step beyond medical management for patients with angina and heart failure. J Am Coll Cardiol. 2007 Oct 16;50(16):1523-31. doi: 10.1016/j.jacc.2007.07.024. Epub 2007 Oct 1. PMID 17936150
• Nichols WW, Estrada JC, Braith RW, Owens K, Conti CR. Enhanced external counterpulsation treatment improves arterial wall properties and wave reflection characteristics in patients with refractory angina. J Am Coll Cardiol. 2006 Sep 19;48(6):1208-14. doi: 10.1016/j.jacc.2006.04.094. Epub 2006 Aug 28. PMID 16979007
• Braith RW, Conti CR, Nichols WW, Choi CY, Khuddus MA, Beck DT, Casey DP. Enhanced external counterpulsation improves peripheral artery flow-mediated dilation in patients with chronic angina: a randomized sham-controlled study. Circulation. 2010 Oct 19;122(16):1612-20. doi: 10.1161/CIRCULATIONAHA.109.923482. Epub 2010 Oct 4. PMID 20921442
• Zhang Y, He X, Chen X, Ma H, Liu D, Luo J, Du Z, Jin Y, Xiong Y, He J, Fang D, Wang K, Lawson WE, Hui JC, Zheng Z, Wu G. Enhanced external counterpulsation inhibits intimal hyperplasia by modifying shear stress responsive gene expression in hypercholesterolemic pigs. Circulation. 2007 Jul 31;116(5):526-34. doi: 10.1161/CIRCULATIONAHA.106.647248. Epub 2007 Jul 9. PMID 17620513

• Yan Zhang, M. D., Principal investigator, First Affiliated Hospital, Sun Yat-Sen University
• Zhensheng Zheng, M. D., Study director, First Affiliated Hospital, Sun Yat-Sen University