By testing with echocardiographic techniques on healthy hearted human subjects, it is shown that the myocardium elastic modulus, defined as the ratio between the equatorial stress in the left ventricular wall and the strain of the left ventricular cavity, results to be independent from the age of subjects at rest. In healthy subjects the treatment with vasoxine, a vessel-constrictor drug, causes an increase in the elastic modulus, the treatment with isoproterenol, an inotropic agent, makes the elastic modulus decrease, whereas the treatment with peritrate, a nitroderivative, does not modify this modulus. In conclusion this parameter, though it cannot be considered a cardiac contractility index, yet it may be utilized to characterize the left ventricular functional state. The alterations caused by the use of vasoxine and isoproterenol in cardiac frequency, left ventricular geometry and arterial pressure, in the examined subjects, are comparable with the alterations reported in the recent literature.