The purpose of this study in humans with stable coronary artery disease (CAD) treatable by percutaneous coronary intervention (PCI) is to evaluate the efficacy of External Counterpulsation (ECP) with regard to the promotion of coronary collateral growth.

Alternative strategies for the promotion of coronary collaterals (arteriogenesis) are a promising therapeutic alternative for at least 20% of all Patients with Coronary Artery Disease (CAD). Beside growth factors, physical exercise has been shown to improve coronary collateral function. Extracorporal Counterpulsation (ECP) mimics physical exercise in a standardized way. Before and after ECP treatment, a quantitative invasive assessment of absolute collateral flow (by calculating the CFI, i.e. Collateral Flow Index) and myocardial perfusion is performed (with calculation of the CPI, i.e. Collateral Perfusion Index and MPR, i.e. Myocardial Perfusion Reserve).

The study setting is single-blinded, sham-controlled and proceptive .

Inclusion Criteria:

• Age > 18 years old
• 1- to 3-vessel coronary artery disease (CAD)
• Stable angina pectoris
• At least 1 stenotic lesion suitable for PCI within the next 4 weeks
• No Q-wave myocardial infarction in the area undergoing CFI measurement
• Written informed consent to participate in the study

Exclusion Criteria:

• Patients admitted as emergencies
• Acute myocardial infarction within the last 3 months
• Unstable CAD
• CAD treated best by CABG
• Coronary stenotic lesion to be treated ad-hoc or within < 4 weeks
• Severe valve disease
• Pulmonary artery hypertension
• Congestive heart failure
• Atrial fibrillation
• Thrombophlebitis and/or deep vein thrombosis
• Occlusive peripheral artery disease
• Abdominal aortic aneurysm