Exercise-mediated adaptations in vascular function and structure: Beneficial effects in coronary artery disease

Exercise exerts direct effects on the vasculature via the impact of hemodynamic forces on the endothelium, thereby leading to functional and structural adaptations that lower cardiovascular risk. The patterns of blood flow and endothelial shear stress during exercise lead to atheroprotective hemodynamic stimuli on the endothelium and contribute to adaptations in vascular function and structure. The structural adaptations observed in arterial lumen dimensions after prolonged exercise supplant the need for acute functional vasodilatation in case of an increase in endothelial shear stress due to repeated exercise bouts. In contrast, wall thickness is affected by rather systemic factors, such as transmural pressure modulated during exercise by generalized changes in blood pressure. Several mechanisms have been proposed to explain the exercise-induced benefits in patients with coronary artery disease (CAD). They include decreased progression of coronary plaques in CAD, recruitment of collaterals, enhanced blood rheological properties, improvement of vascular smooth muscle cell and endothelial function, and coronary blood flow. This review describes how exercise via alterations in hemodynamic factors influences vascular function and structure which contributes to cardiovascular risk reduction, and highlights which mechanisms are involved in the positive effects of exercise on CAD.