Glutamate and Diastolic Function in Patients Undergoing Aortic Valve Repair

Purpose: The effect of intravenous glutamate infusion on myocardial diastolic function and overall hemodynamics were studied in patients undergoing elective aortic valve replacement with severe aortic stenosis and associated left ventricular hypertrophy . Methods: 25 patients will be included in this double-blind randomized placebo-controlled study. Glutamate was administered intravenously immediately after aortic cross-clamp release. The patients receive either a low dose of 30mg kg-1 h-1 (LG-group) or high dose of 60 mg kg-1 h-1 (HG-group) or placebo (P-group) at a rate of 3.3ml kg-1h-1 for 2h. Transesophageal echocardiography (TEE) is used to measure diastolic and systolic ventricular function before sternotomy (T0), and 2h (T2), 3h (T3) and 6h (T4) after release of cross clamp. Additionally routine hemodynamic parameters are measured intraoperatively.