The comparative study of left ventricular ejection fraction (LVEF) between gated blood pool tomography and multiple gated acquisition (MUGA) scan

Abstract

Background: MUGA scan is the nuclear medicine technique used to evaluate left ventricular ejection fraction of the heart. It had high reproducibility in each examination. In cases which MUGA is failed or incorrect result due to tumor obscured the heart, GBPS (gated blood-pool SPECT) is an alternative method. GBPS is not routine practiced at King Chulalongkorn Memorial Hospital (KCMH) service. It is according to capability of scanner and software package for processing. Now, KCMH has the scanner that has this capability but no experience to perform processing and the reliability of results. This study will help technologist to make confidence in processing and nuclear medicine physician to interpret result. Methods: Patients with request for pre- chemotherapy %LVEF base line and volunteer, who did not on drug which affect red blood cell labeling with technetium pertechnetate, were included in this study.  The method of RBC (red blood cell) labeling was modified in vivo technique. Perform MUGA acquisition in LAO (left anterior oblique) view with best septal seen. Preset 1000 heart beats with 64 x 64 matrix, zoom 1.45 with LEUR (low energy ultra-high resolution) collimator on Siemens Symbia T camera and followed by GBPS acquisition with 64 x 64 matrix, zoom 1.45, 64 views over 180 degree rotation arc, duration 50 sec/view, perpendicular configuration detector and start from RAO (right anterior oblique)45 degree. Perform reconstruction and processing for nuclear medicine physician interpretation. Results: Total study was 55 cases (17 males and 38 females) with the age (mean±SD) was 44.38±10.54 years. The relationship between MUGA and GBPS was good correlation with R =0.84. Nuclear medicine physician interpreted 54 cases were within normal limits and one case was abnormal %LVEF. The mean normal value of %LVEF by MUGA was 65.67±4.43 and GBPS was 77.33±7.0. Conclusion: The Patient whom fail to perform MUGA processing can used GBPS for %LVEF evaluation.  %LVEF by GBPS was reproducible for automated processing and correlated well with MUGA with R =0.84. %LVEF by GBPS was higher than MUGA due to left atrium counts was included in MUGA calculation.