Polymerized Placenta Hemoglobin Improves Cardiac Functional Recovery and Reduces Infarction Size of Isolated Rat Heart

Objective: To investigate the cardioprotective effect of polymerized human placenta hemoglobin (PolyPHb) to rat heart subjected to 8-hour hypothermic storage and 2-hour normothermic reperfusion. Methods and Results: Isolated rat hearts were perfused with Langendorff model; after 30 minutes of baseline, the hearts were arrested and stored by St. Thomas' solution (STS) without (STS group) or with 0.5 gHb/dL PolyPHb (PolyPHb group) at 4C for 8 hours, then reperfused for 2 hours. Compared with STS group, PolyPHb in STS greatly improved the recovery of left ventricular developed pressure (LVDP), maximum LVDP increase and decrease rate (dp/dt), coronary flow rate (CF). Also, both the cardiac enzyme release, including creatine kinase (CK) and lactate dehydrogenase (LDH), and myocardial infarction size were significantly reduced in PolyPHb group. Conclusion: Our study demonstrated that the PolyPHb was beneficial to improving cardiac functional recovery and reducing myocardial infarction of 8-hour hypothermic stored rat heart.