Usefulness of Parameters of Left Ventricular Wall Stress and Systolic Function in the Evaluation of Patients with Aortic Stenosis

Left ventricular function and myocardial contractility in aortic stenosis have been intensely studied over the past 40 years. The underlying impetus for a good deal of this work has been to define the interaction between the ventricle and the valve, to predict in an individual patient the clinical course and outcome after aortic valve replacement. Furthermore, the relationship between afterload (wall stress) and contractility has been closely examined. Although wall stress has been shown to be inversely correlated to ejection fraction or fiber shortening, there is wide individual variability for a similar degree of valvular stenosis, which renders interpretation of data regarding left ventricular function and myocardial contractility difficult. A number of other factors affect the response of the left ventricle to chronic pressure overload. The use of stress-shortening relationships in patients with aortic stenosis requires further study before these measures can be advocated for clinical use. This review examines the usefulness of left ventricular wall stress and parameters of left ventricular function in aortic stenosis, dealing with basic concepts, echocardiographic approach, and clinical usefulness.