TY - JOUR
T1 - Sources of variability in the radionuclide angiographic assessment of ejection fraction
T2 - A comparison of first-pass and gated equilibrium techniques
AU - Kaul, Sanjiv
AU - Boucher, Charles A.
AU - Okada, Robert D.
AU - Newell, John B.
AU - Strauss, H. William
AU - Pohost, Gerald M.
N1 - Funding Information:
From the Cardiac Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts. This study was supported in part by U.S. Public Health Service Grants HL 26215, HL 21751 and HL 07535 from the National Heart, Lung, and Blood Institute, the National Institutes of Health, Bethesda, Maryland. Manuscript received June 6, 1983; revised manuscript received November 14, 1983, accepted November 23, 1983.
PY - 1984/3/1
Y1 - 1984/3/1
N2 - Measurements of ejection fractions (EF) determined by first-pass and gated equilibrium radionuclide angiography are widely believed to be equivalent. To compare these measurements in a large group of patients over a wide range of EF values, left ventricular (LV) and right ventricular (RV) EFs at rest were measured in 135 consecutive patients who underwent the 2 methods of radionuclide angiography within 1 hour: first-pass upright with a multi-crystal camera in the anterior projection and gated equilibrium supine with a single-crystal camera in the left anterior oblique projection. The population included 18 normal patients and 117 patients with various cardiac and pulmonary disorders. First-pass and gated equilibrium LVEF correlated well (r = 0.83, p <0.001), but the slope of the regression line was different from unity, with the first-pass values lower than the gated equilibrium values (0.51 ± 0.16 vs 0.56 ± 0.15, p <0.05 [mean ± standard deviation]). Among the 45 patients with a gated equilibrium LVEF of <0.50, the correlation (r = 0.84) was better than that for the 90 patients with a LVEF > 0.50 (r = 0.44, p <0.05). However, in the latter group, the correlation remained good in the 15 patients with cardiomegaly due to aortic or mitral regurgitation (r = 0.80). Inter- and intraobserver error was similar for both methods. In contrast, there was a poor correlation between first-pass and gated equilibrium RVEF, with the first-pass values higher than the gated equilibrium values (0.51 ± 0.11 vs 0.43 ± 0.11, p <0.01). Interobserver error was similar for both the methods, but intraobserver error was better for the first-pass method (p <0.05). Thus, there may be considerable variability in the radionuclide EF at rest in the same patient because of differences in the method of measurement. Caution is suggested when EF values that have been derived using different radionuclide methods are compared.
AB - Measurements of ejection fractions (EF) determined by first-pass and gated equilibrium radionuclide angiography are widely believed to be equivalent. To compare these measurements in a large group of patients over a wide range of EF values, left ventricular (LV) and right ventricular (RV) EFs at rest were measured in 135 consecutive patients who underwent the 2 methods of radionuclide angiography within 1 hour: first-pass upright with a multi-crystal camera in the anterior projection and gated equilibrium supine with a single-crystal camera in the left anterior oblique projection. The population included 18 normal patients and 117 patients with various cardiac and pulmonary disorders. First-pass and gated equilibrium LVEF correlated well (r = 0.83, p <0.001), but the slope of the regression line was different from unity, with the first-pass values lower than the gated equilibrium values (0.51 ± 0.16 vs 0.56 ± 0.15, p <0.05 [mean ± standard deviation]). Among the 45 patients with a gated equilibrium LVEF of <0.50, the correlation (r = 0.84) was better than that for the 90 patients with a LVEF > 0.50 (r = 0.44, p <0.05). However, in the latter group, the correlation remained good in the 15 patients with cardiomegaly due to aortic or mitral regurgitation (r = 0.80). Inter- and intraobserver error was similar for both methods. In contrast, there was a poor correlation between first-pass and gated equilibrium RVEF, with the first-pass values higher than the gated equilibrium values (0.51 ± 0.11 vs 0.43 ± 0.11, p <0.01). Interobserver error was similar for both the methods, but intraobserver error was better for the first-pass method (p <0.05). Thus, there may be considerable variability in the radionuclide EF at rest in the same patient because of differences in the method of measurement. Caution is suggested when EF values that have been derived using different radionuclide methods are compared.
UR - http://www.scopus.com/inward/record.url?scp=0021331110&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0021331110&partnerID=8YFLogxK
U2 - 10.1016/0002-9149(84)90412-0
DO - 10.1016/0002-9149(84)90412-0
M3 - Article
C2 - 6702632
AN - SCOPUS:0021331110
SN - 0002-9149
VL - 53
SP - 823
EP - 828
JO - The American journal of cardiology
JF - The American journal of cardiology
IS - 6
ER -