Iterative estimation for valvular regurgitant fraction measurements by radionuclide angiocardiography

Several models have been developed and iterative estimation techniques have been applied to radionuclide angiocardiographic data to measure valvular regurgitation fractions in animal experiments with controlled amounts of regurgitation. The animal model contains a known amount of regurgitation and comparison of the regurgitant fraction estimated from the mathematical models and that measured from the animal models are compared to validate the non-invasive tracer technique. Several new modifications in the two phase mathematical model of cardiac pump function are introduced and data is presented to validate the use of this technique in future patient studies. The techniqueis applicable to mitral and aortic regurgitation as well as combined valvular incompetence.