Central Hemodynamics and Coronary Blood Flow During Exercise

Abstract

Knowledge of the normal hemodynamic changes associated with exercise is essential to the understanding of exercise physiology. Systolic blood pressure rises progressively as exercise intensity increases. With dynamic exercise, systolic pressures between 30% and 60% above resting values are typically encountered at peak exercise. The percentage increase in pulmonary artery systolic pressure may be even larger. Left atrial pressure also increases, as the systemic ventricle moves up its Starling curve. The transpulmonary gradient (mean pulmonary arter pressure minus mean left atrial pressure) therefore increases only modestly. These changes occur in the setting of a dramatic increase in cardiac output and coronary blood flow. Interactions between the cardiovascular system, skeletal muscle and cardiac muscle contribute to the increase in blood flow.