RT Journal Article SR Electronic T1 Radionuclide First Transit and R-Wave Synchronized Imaging: Correlation of Three Methods of Determining Left Ventricular Ejection Fraction with Contrast Angiography JF Journal of Nuclear Medicine Technology JO J. Nucl. Med. Technol. FD Society of Nuclear Medicine SP 155 OP 157 VO 8 IS 3 A1 Wynant, Gordon E. YR 1980 UL http://tech.snmjournals.org/content/8/3/155.abstract AB Left ventricular ejection fractions in 25 patients, as determined by first transit and R-wave synchronized imaging, were compared with contrast angiography. The ejection fraction obtained by first transit and R-wave synchronized images using a varying region of interest correlated well with the contrast angiography (r=0.96; r=0.99 respectively). Use of a fixed end-diastolic region of interest consistently underestimated the ejection fraction (r=0.92).