The objective of this project is to develop a clinically useful noninvasive radiologic procedure for the diagnosis and evaluation of cardiac failure. The proposed procedure utilizes video fluorodensitometry to evaluate changes in pulmonary blood perfusion distribution and regional pulmonary pulsations that are associated with left ventricular failure. Experimetal studies, using monkeys, will be performed to evaluate the validity of this approach. The experimental procedure has been designed so that if successful, it can be applied in clinical practice with minimal modification.