 This was a prospective, randomized, double blinded study in which patients undergoing a cardiopulmonary bypass CPB with aortic cross clamping were randomly assigned to receive amiodarone, lidocaine, or saline placebo prior to removal of the aortic cross clamp. CPB is a technique that temporarily takes over the function of the heart and lungs during surgery, maintaining the circulation of blood and the oxygen content of the body. Specifically, we will test the hypothesis that amiodarone is superior to both lidocaine and placebo in the prevention of a severely abnormal heart rhythm when the blood flow is restored to the heart after the aortic cross clamp is removed. 