In 38 patients with ‘pure’ aortic stenosis, P terminal force in V<sub>1</sub> (V<sub>1</sub>Ptf) correlated well with left ventricular end-diastolic pressure (LVEDP) (n = 38, r = -0.59, p < 0.001). Poorer, but nevertheless significant correlations were observed with aortic systolic pressure gradient (r = -0.32, p < 0.05) and cardiac volume measured by X-ray (r = -0.34, p < 0.05). No significant correlation was found between V<sub>1</sub>Ptf and peak systolic left ventricular pressure. If V<sub>1</sub>Ptf more negative than -0.03 mm sec is used to detect elevated LVEDP (above 12 mm Hg), the sensitivity is 81 %, and the specificity 86%. Increased left atrial volume is probably the most important mechanism of this relationship. V<sub>1</sub>Ptf is a useful tool for the assessment of the functional and hemodynamic state of the left ventricle in aortic stenosis.