Figure 4. Effects of heat stress on left ventricular end-diastolic and end-systolic volumes, as well as ejection fraction.

A, percentage change in left ventricular end-diastolic and end-systolic blood volumes as a result of whole-body heat stress and time control conditions derived from multi-gated acquisition (MUGA). Heat stress did not significantly alter left ventricular end-diastolic volume whereas left ventricular end-systolic volume was significantly reduced. B, effects of heat stress and time control conditions on left ventricular ejection fraction. There was no difference in ejection fraction between the groups prior to the heat stress or time control periods. Whole-body heating significantly increased left ventricular ejection, while this value was unchanged at the end of the time control period for this group.