Patients with valvular heart disease usually require serial, long-term evaluation to determine changes in the severity of their disorder, its effect on ventricular function, and the advisability of corrective surgery. Echocardiography is excellent technique for visualization of the motion of atrioventricular valves, but it is not reliable method for quantifying valvular insufficiency. Equilibrium radionuclide ventriculography is readily available, noninvasive means for quantifying the degree of valvular insufficiency, using left to right ventricular stroke volume ratio. Besides, other parameters important for cardiac function, such as ventricular volumes and ejecton fraction can also be calculated. In this paper the methodology of equilibrium radionuclide ventriculography and its application to the functional and prognostic characterisation of patients with valvular diseases will be discussed.