An easy noninvasive volume challenge method which takes advantage of the diastolic filling differences existing between patients with recent onset and long-standing hypertension is presented. By passively elevating the patients' legs at 45 degrees for 5 minutes, a sudden increase in venous return was induced in 14 healthy and in 42 hypertensive subjects. The global ejection fraction measured by radionuclide ventriculography increased markedly in both 14 normal subjects and in 18 patients with recent onset hypertension (67 ± 9% to 75 ± 6%, p < 0.001 and 64 ± 10% to 71 ± 11%, p < 0.001, respectively). In contrast, a decrease in global ejection fraction was found in all patients with long-standing hypertension (66 ± 4% to 58 ± 10%, p < 0.001). Similar results were obtained when echocardiographic measurements were made after the legs-up procedure in 24 patients. The correlation with the radionuclide measurements done in the same patients was excellent, r = 0.89. In 20 patients with long-standing hypertension in whom exercise radionuclide ventriculography was done, a marked elevation in global left (LVEF) and right ventricular ejection fraction (RVEF) was found (65 ± 5% to 71.5 ± 11% LVEF, and 42 ± 5% to 45 ± 7% RVEF, p < 0.01), whereas the legs-up procedure induced a significant reduction in both global LVEF and RVEF (65 ± 5% to 57 ± 6% LVEF, and 44 ± 7% to 37 ± 5% RVEF, p < 0.001). Thus it appears that the legs-up procedure is a simple, noninvasive procedure able to detect occult myocardial systolic dysfunction at an early stage of the hypertensive disease.