Fully automated sectorial equilibrium radionuclide ventriculography. Proposal of a method for routine use: exercise and follow-up.

A fully automated computer program is described for processing equilibrium radionuclide ventriculography data with regard to global and sectorial left ventricular ejection fraction. The precise identification of the left ventricular outline, a prerequisite for reproducible determination of sectorial ejection fraction, was achieved by using morphological and functional criteria in a sequential edge detection technique. The high reproducibility of this method (correlation coefficient r: global ejection fraction r = 0.96, sectorial ejection fraction r = 0.82-0.97) allows the evaluation of a mean normal sectorial ejection fraction profile and its adaptation to the individual left ventricle. Computerized comparison between individual and adjusted normal sectorial ejection fraction permits quantitation of the degree and localization of functional impairment at rest, sectorial comparison between ejection fraction at rest and during peak exercise is used for the detection of ischemic functional impairment. The success rate of end diastolic left ventricular edge detection of 96% and the processing time of 150 s makes this method suitable for routine use.