More people die each year from sepsis, a severe, overwhelming infection and inflammation, than from breast or colon cancer. The infection is also 20 times more deadly than a heart attack. Septic shock (severe sepsis) causes multiple organ failure and is the leading cause of death in North American intensive care units. Sepsis impairs the heart’s ability to use oxygen, which is necessary for the heart to pump normally. Dr. Ryon Bateman is investigating whether damage to capillaries (the smallest blood vessels) prevents oxygen from being delivered within the heart or whether dysfunction of the mitochondria (the parts of the cell that consume oxygen) prevents oxygen from being used by the heart. Dr. Bateman is using advanced microscopic imaging techniques to generate three-dimensional images of heart capillaries to look for changes in their number and spacing. He is also assessing whether regions of the heart with low oxygen have tissue damage, and if mitochondria are damaged in these regions. The research could explain why the heart is damaged during sepsis, leading to new treatments for critically ill septic patients.