“…12B) relative to exercise-induced increases in MVO 2 in swine (94). As depicted in Figure 12B, coronary venous PO 2 typically falls modestly as MVO 2 increases with exercise (94, 111, 213, 214, 274, 278, 280, 281, 283, 285, 293–295, 388,389,454,483,484,497,559,642,664,669,920,921,923); however, this response can vary with little/no change in swine (94, 111, 281, 663, 664, 667, 669), moderate reductions in humans (454,483,484,563), with the largest decreases typically observed in dogs (32, 274, 276, 282, 283, 285, 424, 920, 921,923–925). These reductions in PO 2 reflect slight increases in oxygen extraction that occur along with elevations in coronary blood flow in response to elevations in MVO 2 .…”