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.

Inclusion Criteria:

• severe aortic stenosis
• left ventricular hypertrophy of more than 10mm IVS thickness
• normal ejection fraction
• SR

Exclusion Criteria:

• moderately or severely reduced systolic left ventricular function (ejection fraction <30%)
• atrial fibrillation or flutter
• intolerance to glutamate.