The intraoperative central aortic pressure measurement will be accomplished with the help of the cardiothoracic surgeon. The surgeon will place a catheter in the aorta as part of the coronary artery bypass grafting surgery. This catheter will be connected to the artificial heart-lung machine. Prior to turning on the heart-lung machine, the pressure in the aorta will be measured with this catheter. This is the standard of care for this type of surgery and will not delay the surgery. After the artificial heart-lung machine is turned off but before the catheter is removed from the aorta, the pressure will once again be measured.