The diabetic heart is more sensitive to ischemic injury.

Clinical studies have suggested that the diabetic heart is more sensitive to ischemic injury than the non-diabetic heart. However, results from a number of experimental studies using animal models of diabetes reported no change, increased or decreased sensitivity to ischemia. The purpose of this review is to discuss the possible explanations for this apparent discrepancy. Analysis of the conflicting literature on this subject reveals a pattern which suggests that the disparity of experimental findings stems from differences in the duration and severity of the diabetic state, the ischemic flow rate and whether fatty acids are provided as an exogenous substrate. It appears that short-term or mild diabetes is associated with decreased sensitivity to zero-flow ischemic injury. However, as the duration or severity of diabetes increases, this beneficial effect disappears. The diabetic heart also appears to be more vulnerable to injury during low-flow ischemia and when elevated fatty acids are present.