Effects Of Doxycycline On MMP-2 In Patients Undergoing CPB

Objective:To explore the law of MMP-2 secretion during CPB,and to observe the effects on MMP-2 levels of TIMP during CPB and peri-operation.Methods:32 cases with rheumatic heart disease,mitral disease were randomly divided into groupâ… (n=16) and groupâ…¡(n=16).Pre-operative treatment of groupâ… is in conventional processing,the patients of groupâ…¡take orally 100mg doxycycline ahead of one day before operation, until third day after operation,two times each day.There were no difference in other treatment of two groups,mitral valves were replaced under CPB in the same way.All patients in two groups were drawn vein blood samples respectively at the times:1 day pre-operation(T1),1 min before CPB(T2),1 min before aortic cross-clamping(T3),1 min after aortic declamping(T4),15 min after aortic declmping(T5),and 3 day post-operation(T6).The concentration MMP-2 in plasma were tested.Results:The concentration of the MMP-2 in plasma of patients in groupâ… reached to its top at T4,and gradually reduced after that,but it in 3 day post-operation was higher than pre-operation.However,there was no obvious difference between groupâ… and groupâ…¡at T1, and was lower at other times,no obvious peak value appeared.Conclusion:For CPB patients myocardium having ischemic-reperfusion injury can make MMP-2 level elevate obviously ,TIMP can restrain the increasing MMP-2.