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Esmolol protects the myocardium and facilitates direct version intracardiac operation with a beating heart.

In recent years there has been renewed interest in beating heart surgery using the ultra-active and selective beta1-blocker, esmolol. However, there has not been a report of its use in direct version intracardiac surgery with beating heart. Twenty-four patients undergoing elective direct version intracardiac surgery (mitral valve replacement) were divided randomly into 2 groups: control group (normothermia cardiopulmonary bypass (CPB) direct version intracardiac beating heart surgery) and esmolol group (normothermia CPB direct version intracardiac beating heart surgery and intravenous esmolol drip during CPB to maintain heart rate at 30-50 beats/min). Steady hemodynamic parameters were maintained in both groups; however, the doses of dopamine used in control group were larger than those for the esmolol group (p<0.01). The myocardial ultrastructure was well maintained in both group, but the scores for myocardial mitochondria, glycogen grading and counting and the amount of adenosine triphosphate were higher in the esmolol group (p<0.05). There was no significant change in the malondialdehyde level in either group (p>0.05). Using esmolol in direct version intracardiac beating heart surgery protects the myocardium and facilitates the operation.