Infarct Size With Incremental Global Myocardial Ischemia Times: Cyclosporine A in Donation After Circulatory Death Rat Hearts.

BACKGROUND:We quantified the myocardial infarct size with varying global ischemia durations and studied the benefits of Cyclosporine A (CyA) in reducing cardiac injury in ex vivo and transplanted rat hearts. METHODS:Infarct size was measured after 15, 20, 25, 30, and 35 minutes of in vivo global ischemia (n = 34) and compared with control beating-heart donor (CBD) hearts (n = 10). For heart function assessment, donation after circulatory death (DCD) rat hearts (n = 20) were procured after 25 minutes of in vivo ischemia and reanimated ex vivo for 90 minutes. Half of the DCD hearts received CyA (0.5 mM) at reanimation. The CBD hearts (n = 10) served as controls. A separate group of CBD and DCD (with or without CyA treatment) hearts underwent heterotopic heart transplantation; heart function was measured at 48 hours. RESULTS:Infarct size was 25% with 25 minutes of ischemia and increased significantly with 30 and 35 minutes to 32% and 41%, respectively. CyA treatment decreased infarct size in DCD hearts (15% vs 25%). Heart function in the transplanted DCD hearts was significantly better with CyA treatment and was comparable to CBD hearts. CONCLUSIONS:CyA administered at reperfusion limited infarct size in DCD hearts and improved their function in transplanted hearts.