Intense Exercise and Native Collateral Function in Stable Moderate Coronary Artery Disease

Physical Activity in the Prevention and Treatment of Coronary Artery Disease

“…Therefore, it seems unlikely that the small change in collateral flow with exercise training is responsible for clinical improvement. 8 Taken together, these minor changes in CFI with exercise training do not support the idea of exercise-induced growth of epicardial collateral conductance vessels, which redirect blood flow to ischemic myocardium. Moreover, improved endothelial function and, hence, reduced resistance of collateral supply arteries might cause exercise-related perfusion of preexisting collateral channels and changes in CFI (Figure 3).…”

“…This result was much higher than the previously documented upper threshold of 30 to 35 mm Hg coronary perfusion pressure that was associated with myocardial ischemia and sufficient stimulation of collateral growth. Therefore, it seems unlikely that the small change in collateral flow with exercise training is responsible for clinical improvement 8. Taken together, these minor changes in CFI with exercise training do not support the idea of exercise‐induced growth of epicardial collateral conductance vessels, which redirect blood flow to ischemic myocardium.…”

“…Mechanistically, numerous studies suggest that regular physical activity partially reverses endothelial alterations: it enhances the vascular production of NO, decreases the generation of reactive oxygen species (ROS; which would otherwise rapidly inactivate NO), rejuvenates the endothelium by activating endogenous progenitor cells, induces the CPC‐mediated formation of new vessels by vasculogenesis, and promotes myocardial expression of vascular growth factors (which induce the remodeling of preexisting capillaries and arterioles) 1. An exercise training‐induced regression of coronary stenosis and collateral growth has been discussed as a potential mechanism that also contributes to enhanced myocardial perfusion; however, a critical review of the literature raises reasonable doubts that the magnitude of these changes is large enough to explain their survival benefit in CAD 3, 8. Nevertheless, a limited number of recent studies indicate that regular physical activity has an inhibitory effect on platelet and leukocyte activation 9…”

“…1 An exercise training-induced regression of coronary stenosis and collateral growth has been discussed as a potential mechanism that also contributes to enhanced myocardial perfusion; however, a critical review of the literature raises reasonable doubts that the magnitude of these changes is large enough to explain their survival benefit in CAD. 3,8 Nevertheless, a limited number of recent studies indicate that regular physical activity has an inhibitory effect on platelet and leukocyte activation. 9 This review will discuss the effects of regular physical activity on vasculature in the primary and secondary prevention of CAD in humans, with a special focus on the endothelium.…”

Value of Relative Myocardial Perfusion at MRI for Fractional Flow Reserve–Defined Ischemia: A Pilot Study

“…The proportion of subjects with longstanding symptoms in different study samples theoretically influences the correlations between FFR and stress-perfusion MRI. Coronary microcollateral vessels may develop after long-duration flow reduction, especially when regular physical exercise is performed [22], although this was shown recently to affect the FFR value marginally [23]. A possibly higher proportion of microvascular disease in our study sample as compared with the previous studies should be contemplated as well.…”