Click on image to view larger version.

Figure 2 Possible Mechanisms Responsible for the Clinical Benefit Associated With EECP Therapy

Acute afterload reduction decreases myocardial demand. By increasing coronary blood flow, enhanced external counterpulsation (EECP) therapy is thought to promote myocardial collateralization via opening of preformed collateral vessels, arteriogenesis, and angiogenesis. Increased blood flow and shear stress also may improve coronary endothelial function, favoring vasodilation and myocardial perfusion. In addition, improvement in endothelial function may further promote collateral formation by arteriogenesis and angiogenesis. In addition to a peripheral training effect, a minor placebo effect is considered to contribute to the symptomatic benefit of EECP therapy. ET = endothelin; NO = nitric oxide.