To perform a head-to-head comparison between magnetic resonance imaging (MRI) and
gated single-photon emission computed tomography (SPECT) for the evaluation of left
ventricular (LV) function (LV ejection fraction [LVEF], LV volumes, and regional wall
motion) in patients with ischemic cardiomyopathy, we studied 22 patients with chronic
coronary artery disease and LV dysfunction. Multislice, multiphase echoplanar MRI
was performed with Philips Gyroscan ACS-NT15. Image analysis was performed using the
MASS software package to determine LV end-systolic volume, LV end-diastolic volume,
and LVEF. The same parameters were calculated using quantitative gated SPECT software
(QGS, Cedars-Sinai Medical Center). The different parameters were compared using linear
regression, and correlation coefficients were calculated. Regional wall motion was
also determined from both techniques, according to a 13-segment model and a 3-point
scoring system (from 1 = normokinesia to 3 = akinesia or dyskinesia). A summed wall
motion score was also calculated for MRI and gated SPECT. Good correlations were found
between MRI and gated SPECT for all parameters: (1) summed wall motion scoreMRI versus
summed wall motion scoreSPECT: y = 0.74x + 8.0, r = 0.88, p <0.01; (2) LV end-systolic
volumeMRI versus LV end-systolic volumeSPECT: y = 0.94x - 12.3, r = 0.87, p <0.01;
(3) LV end-diastolic volumeMRI versus LV end-diastolic volumeSPECT: y = 0.93x - 18.4,
r = 0.84, p <0.01; and (4) LVEFMRI versus LVEFSPECT: y = 0.97x + 0.68, r = 0.90, p
<0.01. For regional wall motion, an exact agreement of 83% was found, with a kappa
statistic of 0.77 (95% confidence intervals 0.71 to 0.83, SE 0.03), indicating essentially
excellent agreement. Thus, close and significant correlations were observed for assessment
of LVEF, LV volumes, and regional wall motion by MRI and gated SPECT in patients with
ischemic cardiomyopathy.