Inclusion Criteria:  Patient willing and capable of providing informed consent and physically capable of performing study related activities Patient undergoing any of the following types of cardiac surgeries:  Aortic valve repair Aortic valve replacement Mitral valve repair Mitral valve replacement Tricuspid valve repair Tricuspid valve replacement Pulmonic valve repair Pulmonic valve replacement Ascending aorta replacement Coronary Artery Bypass Graft (CABG) surgery  Exclusion Criteria:  Pregnant women Patients known to be under the jurisdiction of the Department of Corrections Patients with persistent arrhythmias as confirmed by the principal investigator (MacKay) on a caseby-case basis (e.g. atrial fibrillation, atrial flutter, frequent premature ventricular contractions, frequent premature atrial contractions, etc.) Patients with a contraindication to Pulmonary Arterial Catheter (PAC) monitoring as confirmed by the principal investigator (MacKay) on a case-by-case basis (e.g. tricuspid or pulmonic valve endocarditis, venous thrombosis present in the superior vena cava, right atrium, or main pulmonary artery) Patients with a contraindication to TEE monitoring as confirmed by the principal investigator (MacKay) on a case-by-case basis (e.g. previous esophageal surgery, prior gastric bypass surgery, esophageal varices).