Abstract
This study was performed to establish the normal values and range of variability for three- and five-segment regional ejection fraction analysis. In addition, file conversion was utilized to compare global values produced by different vendors’ systems. Global values show considerable differences between systems (15%-20% in most cases) which indicate the need for standardization and correction when comparing data. For regional analysis, with a mean global value of 60.6%, the mean regional ejection fractions varied from 47% to 81%. Interobserver variation of the regional parameters was between 2% and 6% (standard error of estimate) for a group of 50 “normals” (global ejection fraction >50%) with least variability in the apex and maximum in the septal segment. Intraobserver variability was between 1% and 4% with the same pattern. In a mixed population (global ejection fraction 10%–85%) all parameters exhibited more variability, and paying strict attention to patient positioning for repeat studies appears to have little effect on reducing this variation.
