Effects of adenosine supplementing cold blood cardioplegia on myocardial injury in patients undergoing mitral valve replacement

Abstract

Objective To investigate the effects of adenosine supplementing cold blood cardioplegia on myocardial injury in patients undergoing milral valve replacement(MVR).Methods Thirty ASA Ⅱ or Ⅲ patients aged 18-64 yr with a BMI of 18-24 kg/m2 undergoing elective MVR were randomly divided into 2 groups(n =15each):control group(C)and adenosine group(A).In group A myocardial arrest was produced by infusing adenosine 6 mg diluted in normal saline 20 ml through aortic root after aorta was cross-clamped followed by cold blood cardiaplegic solution 20 mg/kg.In group C asystole was produced with cold blood cardioplegic solution 20 ml/kg alone every 30 min.Blood samples were taken from central vein at 5 min before(T1)and 4 h after aortic crossclamping(T2)and 24 h after operation(T3)for determination of plasma cardiac troponin Ⅰ(cTnI)concentration and creatine kinase-MB(CK-MB)activity.The amount of cardioplegic solution infused,cardiac arrest induction time(from infusion of adenosine or cardioplegic solution to asystole shown by ECG),restoration of spontaneous heartbeat,the amount of dopamine administered during the 2 h after CPB and aortic cross-clamping time were recorded.Results Supplementation of cold blood cardioplegia with adenosine significantly reduced cardiac arrest induction time,the total amount of dopamine administered during the 2 h after CPB and plasma cTnl concentration and CK-MB activity in group A compared with group C.Conclusion Cold blood cardioplegia supplemented with adenosine can attenuate myocardial injury in patients undergoing MVR. Key words: Adenosine; Myocardial reperfusion injury; Cardiopulmonary bypass; Intraopcrative complications; Heart valve prosthesis implantation