In-human Validation of a Technique for Measuring Central Aortic Hemodynamics With Peripheral Arterial Waveforms

The following additional research related procedures will be performed in patients recruited into the study: 1) a small cuff will be placed on one the finger of each subject to measure the pulse in the finger (Finapres); 2) a cannula will be placed in the femoral artery by the surgeon to measure femoral artery pressure; 3) for a period of two minutes immediately before and after the cardiopulmonary bypass a small cannula (the size of a pencil tip) will be inserted by the surgeon under direct vision into the aorta and 4) the information from each of these cannula will be recorded on a computer for later study.