This study involves research using human subjects (cardiac surgical patients) to evaluate the effect of remote ischemic preconditioning (RIPC) on cardioprotective outcomes. RIPC applied to upper or lower extremities has been shown cardioprotective role by lowering release of cardiac troponin in patients with cardiac diseases. However, it is not clear whether anesthetics, such as propofol or sevoflurane, may impair the cardioprotective effect of RIPC in cardiac surgical patients. Therefore, the purpose of the study is to compare the effects of anesthetics on cardioprotection of RIPC in patients undergoing cardiac surgery.